Sample records for average interplanetary magnetic

  1. An interplanetary magnetic field ensemble at 1 AU

    NASA Technical Reports Server (NTRS)

    Matthaeus, W. H.; Goldstein, M. L.; King, J. H.

    1985-01-01

    A method for calculation ensemble averages from magnetic field data is described. A data set comprising approximately 16 months of nearly continuous ISEE-3 magnetic field data is used in this study. Individual subintervals of this data, ranging from 15 hours to 15.6 days comprise the ensemble. The sole condition for including each subinterval in the averages is the degree to which it represents a weakly time-stationary process. Averages obtained by this method are appropriate for a turbulence description of the interplanetary medium. The ensemble average correlation length obtained from all subintervals is found to be 4.9 x 10 to the 11th cm. The average value of the variances of the magnetic field components are in the approximate ratio 8:9:10, where the third component is the local mean field direction. The correlation lengths and variances are found to have a systematic variation with subinterval duration, reflecting the important role of low-frequency fluctuations in the interplanetary medium.

  2. Interplanetary magnetic field data book

    NASA Technical Reports Server (NTRS)

    King, J. H.

    1975-01-01

    An interplanetary magnetic field (IMF) data set is presented that is uniform with respect to inclusion of cislunar IMF data only, and which has as complete time coverage as presently possible over a full solar cycle. Macroscale phenomena in the interplanetary medium (sector structure, heliolatitude variations, solar cycle variations, etc.) and other phenomena (e.g., ground level cosmic-ray events) for which knowledge of the IMF with hourly resolution is necessary, are discussed. Listings and plots of cislunar hourly averaged IMP parameters over the period November 27, 1963, to May 17, 1974, are presented along with discussion of the mutual consistency of the IMF data used herein. The magnetic tape from which the plots and listings were generated, which is available from the National Space Science Data Center (NSSDC), is also discussed.

  3. Large-scale properties of the interplanetary magnetic field

    NASA Technical Reports Server (NTRS)

    Schatten, K. H.

    1972-01-01

    Early theoretical work of Parker is presented along with the observational evidence supporting his Archimedes spiral model. Variations present in the interplanetary magnetic field from the spiral angle are related to structures in the solar wind. The causes of these structures are found to be either nonuniform radial solar wind flow or the time evolution of the photospheric field. Coronal magnetic models are related to the connection between the solar magnetic field and the interplanetary magnetic field. Direct extension of the solar field-magnetic nozzle controversy is discussed along with the coronal magnetic models. Effects of active regions on the interplanetary magnetic field is discussed with particular reference to the evolution of interplanetary sectors. Interplanetary magnetic field magnitude variations are shown throughout the solar cycle. The percentage of time the field magnitude is greater than 10 gamma is shown to closely parallel sunspot number. The sun's polar field influence on the interplanetary field and alternative views of the magnetic field structure out of the ecliptic plane are presented. In addition, a variety of significantly different interplanetary field structures are discussed.

  4. Interplanetary Magnetic Field Guiding Relativistic Particles

    NASA Technical Reports Server (NTRS)

    Masson, S.; Demoulin, P.; Dasso, S.; Klein, K. L.

    2011-01-01

    The origin and the propagation of relativistic solar particles (0.5 to few Ge V) in the interplanetary medium remains a debated topic. These relativistic particles, detected at the Earth by neutron monitors have been previously accelerated close to the Sun and are guided by the interplanetary magnetic field (IMF) lines, connecting the acceleration site and the Earth. Usually, the nominal Parker spiral is considered for ensuring the magnetic connection to the Earth. However, in most GLEs the IMF is highly disturbed, and the active regions associated to the GLEs are not always located close to the solar footprint of the nominal Parker spiral. A possible explanation is that relativistic particles are propagating in transient magnetic structures, such as Interplanetary Coronal Mass Ejections (ICMEs). In order to check this interpretation, we studied in detail the interplanetary medium where the particles propagate for 10 GLEs of the last solar cycle. Using the magnetic field and the plasma parameter measurements (ACE/MAG and ACE/SWEPAM), we found widely different IMF configurations. In an independent approach we develop and apply an improved method of the velocity dispersion analysis to energetic protons measured by SoHO/ERNE. We determined the effective path length and the solar release time of protons from these data and also combined them with the neutron monitor data. We found that in most of the GLEs, protons propagate in transient magnetic structures. Moreover, the comparison between the interplanetary magnetic structure and the interplanetary length suggest that the timing of particle arrival at Earth is dominantly determined by the type of IMF in which high energetic particles are propagating. Finally we find that these energetic protons are not significantly scattered during their transport to Earth.

  5. Interplanetary boundary layers at 1 AU. [magnetic field measurements from Explorer 34

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Lemaire, J. F.; Turner, J. M.

    1976-01-01

    The structure and nature of discontinuities in the interplanetary magnetic field at 1 AU in the period March 18, 1971 to April 9, 1971, is determined by using high-resolution magnetic field measurements from Explorer 34. The discontinuities that were selected for this analysis occurred under a variety of interplanetary conditions at an average rate of 0.5/hr. This set does not include all discontinuities that were present, but the sample is large and it is probably representative. Both tangential and rotational discontinuities were identified, the ratio of TD's to RD's being approximately 3 to 1. Tangential discontinuities were observed every day, even among Alfvenic fluctuations. The structure of most of the boundary layers was simple and ordered, i.e., the magnetic field usually changed smoothly and monotonically from one side of the boundary layer to the other.

  6. CHARGED DUST GRAIN DYNAMICS SUBJECT TO SOLAR WIND, POYNTING–ROBERTSON DRAG, AND THE INTERPLANETARY MAGNETIC FIELD

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lhotka, Christoph; Bourdin, Philippe; Narita, Yasuhito, E-mail: christoph.lhotka@oeaw.ac.at, E-mail: philippe.bourdin@oeaw.ac.at, E-mail: yasuhito.narita@oeaw.ac.at

    We investigate the combined effect of solar wind, Poynting–Robertson drag, and the frozen-in interplanetary magnetic field on the motion of charged dust grains in our solar system. For this reason, we derive a secular theory of motion by the means of an averaging method and validate it with numerical simulations of the unaveraged equations of motions. The theory predicts that the secular motion of charged particles is mainly affected by the z -component of the solar magnetic axis, or the normal component of the interplanetary magnetic field. The normal component of the interplanetary magnetic field leads to an increase ormore » decrease of semimajor axis depending on its functional form and sign of charge of the dust grain. It is generally accepted that the combined effects of solar wind and photon absorption and re-emmision (Poynting–Robertson drag) lead to a decrease in semimajor axis on secular timescales. On the contrary, we demonstrate that the interplanetary magnetic field may counteract these drag forces under certain circumstances. We derive a simple relation between the parameters of the magnetic field, the physical properties of the dust grain, as well as the shape and orientation of the orbital ellipse of the particle, which is a necessary conditions for the stabilization in semimajor axis.« less

  7. Genesis of Interplanetary Intermittent Turbulence: a Case Study of Rope-Rope Magnetic Reconnection

    NASA Technical Reports Server (NTRS)

    Chian, Abraham C.- L.; Feng, Heng Q.; Hu, Qiang; Loew, Murray H.; Miranda, Rodrigo A.; Munoz, Pablo R.; Sibeck, David G.; Wu, De J.

    2016-01-01

    In a recent paper, the relation between current sheet, magnetic reconnection, and turbulence at the leading edge of an interplanetary coronal mass ejection was studied. We report here the observation of magnetic reconnection at the interface region of two interplanetary magnetic flux ropes. The front and rear boundary layers of three interplanetary magnetic flux ropes are identified, and the structures of magnetic flux ropes are reconstructed by the Grad Shafranov method. A quantitative analysis of the reconnection condition and the degree of intermittency reveals that rope-rope magnetic reconnection is the most likely site for genesis of interplanetary intermittency turbulence in this event. The dynamic pressure pulse resulting from this reconnection triggers the onset of a geomagnetic storm.

  8. Interplanetary medium data book, appendix

    NASA Technical Reports Server (NTRS)

    King, J. H.

    1977-01-01

    Computer generated listings of hourly average interplanetary plasma and magnetic field parameters are given. Parameters include proton temperature, proton density, bulk speed, an identifier of the source of the plasma data for the hour, average magnetic field magnitude and cartesian components of the magnetic field. Also included are longitude and latitude angles of the vector made up of the average field components, a vector standard deviation, and an identifier of the source of magnetic field data.

  9. GENESIS OF INTERPLANETARY INTERMITTENT TURBULENCE: A CASE STUDY OF ROPE–ROPE MAGNETIC RECONNECTION

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chian, Abraham C.-L.; Loew, Murray H.; Feng, Heng Q.

    In a recent paper, the relation between current sheet, magnetic reconnection, and turbulence at the leading edge of an interplanetary coronal mass ejection was studied. We report here the observation of magnetic reconnection at the interface region of two interplanetary magnetic flux ropes. The front and rear boundary layers of three interplanetary magnetic flux ropes are identified, and the structures of magnetic flux ropes are reconstructed by the Grad–Shafranov method. A quantitative analysis of the reconnection condition and the degree of intermittency reveals that rope–rope magnetic reconnection is the most likely site for genesis of interplanetary intermittency turbulence in this event.more » The dynamic pressure pulse resulting from this reconnection triggers the onset of a geomagnetic storm.« less

  10. Interplanetary magnetic field effects on high latitude ionospheric convection

    NASA Technical Reports Server (NTRS)

    Heelis, R. A.

    1985-01-01

    Relations between the electric field and the electric current in the ionosphere can be established on the basis of a system of mathematical and physical equations provided by the equations of current continuity and Ohm's law. For this reason, much of the synthesis of electric field and plasma velocity data in the F-region is made with the aid of similar data sets derived from field-aligned current and horizontal current measurements. During the past decade, the development of a self-consistent picture of the distribution and behavior of these measurements has proceeded almost in parallel. The present paper is concerned with the picture as it applies to the electric field and plasma drift velocity and its dependence on the interplanetary magnetic field. Attention is given to the southward interplanetary magnetic field and the northward interplanetary magnetic field.

  11. The interplanetary and solar magnetic field sector structures, 1962 - 1968

    NASA Technical Reports Server (NTRS)

    Jones, D. E.

    1972-01-01

    The interplanetary magnetic field sector structure was observed from late 1962 through 1968. During this time it has been possible to study the manner in which the sector pattern and its relation to the photospheric magnetic field configuration changes from solar minimum to solar maximum. Observations were also made relating sector boundaries to specific regions on the solar disk. These and other observations related to the solar origin of the interplanetary field are briefly reviewed.

  12. Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun

    NASA Astrophysics Data System (ADS)

    Amenomori, M.; Bi, X. J.; Chen, D.; Chen, T. L.; Chen, W. Y.; Cui, S. W.; Danzengluobu, Ding, L. K.; Feng, C. F.; Feng, Zhaoyang; Feng, Z. Y.; Gou, Q. B.; Guo, Y. Q.; He, H. H.; He, Z. T.; Hibino, K.; Hotta, N.; Hu, Haibing; Hu, H. B.; Huang, J.; Jia, H. Y.; Jiang, L.; Kajino, F.; Kasahara, K.; Katayose, Y.; Kato, C.; Kawata, K.; Kozai, M.; Labaciren, Le, G. M.; Li, A. F.; Li, H. J.; Li, W. J.; Liu, C.; Liu, J. S.; Liu, M. Y.; Lu, H.; Meng, X. R.; Miyazaki, T.; Mizutani, K.; Munakata, K.; Nakajima, T.; Nakamura, Y.; Nanjo, H.; Nishizawa, M.; Niwa, T.; Ohnishi, M.; Ohta, I.; Ozawa, S.; Qian, X. L.; Qu, X. B.; Saito, T.; Saito, T. Y.; Sakata, M.; Sako, T. K.; Shao, J.; Shibata, M.; Shiomi, A.; Shirai, T.; Sugimoto, H.; Takita, M.; Tan, Y. H.; Tateyama, N.; Torii, S.; Tsuchiya, H.; Udo, S.; Wang, H.; Wu, H. R.; Xue, L.; Yamamoto, Y.; Yamauchi, K.; Yang, Z.; Yuan, A. F.; Yuda, T.; Zhai, L. M.; Zhang, H. M.; Zhang, J. L.; Zhang, X. Y.; Zhang, Y.; Zhang, Yi; Zhang, Ying; Zhaxisangzhu, Zhou, X. X.; Tibet AS γ Collaboration

    2018-01-01

    We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54 ±0.21stat±0.20syst (1.62 ±0.15stat±0.22syst ) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

  13. Evaluation of the Interplanetary Magnetic Field Strength Using the Cosmic-Ray Shadow of the Sun.

    PubMed

    Amenomori, M; Bi, X J; Chen, D; Chen, T L; Chen, W Y; Cui, S W; Danzengluobu; Ding, L K; Feng, C F; Feng, Zhaoyang; Feng, Z Y; Gou, Q B; Guo, Y Q; He, H H; He, Z T; Hibino, K; Hotta, N; Hu, Haibing; Hu, H B; Huang, J; Jia, H Y; Jiang, L; Kajino, F; Kasahara, K; Katayose, Y; Kato, C; Kawata, K; Kozai, M; Labaciren; Le, G M; Li, A F; Li, H J; Li, W J; Liu, C; Liu, J S; Liu, M Y; Lu, H; Meng, X R; Miyazaki, T; Mizutani, K; Munakata, K; Nakajima, T; Nakamura, Y; Nanjo, H; Nishizawa, M; Niwa, T; Ohnishi, M; Ohta, I; Ozawa, S; Qian, X L; Qu, X B; Saito, T; Saito, T Y; Sakata, M; Sako, T K; Shao, J; Shibata, M; Shiomi, A; Shirai, T; Sugimoto, H; Takita, M; Tan, Y H; Tateyama, N; Torii, S; Tsuchiya, H; Udo, S; Wang, H; Wu, H R; Xue, L; Yamamoto, Y; Yamauchi, K; Yang, Z; Yuan, A F; Yuda, T; Zhai, L M; Zhang, H M; Zhang, J L; Zhang, X Y; Zhang, Y; Zhang, Yi; Zhang, Ying; Zhaxisangzhu; Zhou, X X

    2018-01-19

    We analyze the Sun's shadow observed with the Tibet-III air shower array and find that the shadow's center deviates northward (southward) from the optical solar disk center in the "away" ("toward") interplanetary magnetic field (IMF) sector. By comparing with numerical simulations based on the solar magnetic field model, we find that the average IMF strength in the away (toward) sector is 1.54±0.21_{stat}±0.20_{syst} (1.62±0.15_{stat}±0.22_{syst}) times larger than the model prediction. These demonstrate that the observed Sun's shadow is a useful tool for the quantitative evaluation of the average solar magnetic field.

  14. Observations of a Small Interplanetary Magnetic Flux Rope Opening by Interchange Reconnection

    NASA Astrophysics Data System (ADS)

    Wang, J. M.; Feng, H. Q.; Zhao, G. Q.

    2018-01-01

    Interchange reconnection, specifically magnetic reconnection between open magnetic fields and closed magnetic flux ropes, plays a major role in the heliospheric magnetic flux budget. It is generally accepted that closed magnetic field lines of interplanetary magnetic flux ropes (IMFRs) can gradually open through reconnection between one of its legs and other open field lines until no closed field lines are left to contribute flux to the heliosphere. In this paper, we report an IMFR associated with a magnetic reconnection exhaust, whereby its closed field lines were opening by a magnetic reconnection event near 1 au. The reconnection exhaust and the following IMFR were observed on 2002 February 2 by both the Wind and ACE spacecraft. Observations on counterstreaming suprathermal electrons revealed that most magnetic field lines of the IMFR were closed, especially those after the front boundary of the IMFR, with both ends connected to the Sun. The unidirectional suprathermal electron strahls before the exhaust manifested the magnetic field lines observed before the exhaust was open. These observations provide direct evidence that closed field lines of IMFRs can be opened by interchange reconnection in interplanetary space. This is the first report of the closed field lines of IMFRs being opened by interchange reconnection in interplanetary space. This type of interplanetary interchange reconnection may pose important implications for balancing the heliospheric flux budget.

  15. Variation with interplanetary sector of the total magnetic field measured at the OGO 2, 4, and 6 satellites

    NASA Technical Reports Server (NTRS)

    Langel, R. A.

    1973-01-01

    Variations in the scalar magnetic field (delta B) from the polar orbiting OGO 2, 4, and 6 spacecraft are examined as a function of altitude for times when the interplanetary magnetic field is toward the sun and for times when the interplanetary magnetic field away from the sun. This morphology is basically the same as that found when all data, irrespective of interplanetary magnetic sector, are averaged together. Differences in delta B occur, both between sectors and between seasons, which are similar in nature to variations in the surface delta Z found by Langel (1973c). The altitude variation of delta B at sunlit local times, together with delta Z at the earth's surface, demonstrates that the delta Z and delta B which varies with sector has an ionospheric source. Langel (1973b) showed that the positive delta B region in the dark portion of the hemisphere is due to at least two sources, the westward electrojet and an unidentified non-ionospheric source(s). Comparison of magnetic variations between season/sector at the surface and at the satellite, in the dark portion of the hemisphere, indicates that these variations are caused by variations in the latitudinally narrow electrojet currents and not by variations in the non-ionospheric source of delta B.

  16. Magnetic holes in the solar wind. [(interplanetary magnetic fields)

    NASA Technical Reports Server (NTRS)

    Turner, J. M.; Burlaga, L. F.; Ness, N. F.; Lemaire, J. F.

    1976-01-01

    An analysis is presented of high resolution interplanetary magnetic field measurements from the magnetometer on Explorer 43 which showed that low magnetic field intensities in the solar wind at 1 AU occur as distinct depressions or 'holes'. These magnetic holes are new kinetic-scale phenomena, having a characteristic dimension on the order of 20,000 km. They occurred at a rate of 1.5/day in the 18-day time span (March 18 to April 6, 1971) that was analyzed. Most of the magnetic holes are characterized by both a depression in the absolute value of the magnetic field, and a change in the magnetic field direction; some of these are possibly the result of magnetic merging. However, in other cases the magnetic field direction does not change; such holes are not due to magnetic merging, but might be a diamagnetic effect due to localized plasma inhomogeneities.

  17. Interplanetary magnetic field orientation for transient events in the outer magnetosphere

    NASA Technical Reports Server (NTRS)

    Sibeck, D. G.; Newell, P. T.

    1995-01-01

    It is generally believed that flux transfer events (FTEs) in the outer dayside magneosphere, usually identified by transient (approximately 1 min) bipolar magneitc field perturbations in the direction normal to the nominal magnetopause, occur when the magnetosheath magetic field has a southward component. We compare the results of three methods for determining the magnetosheath magnetic field orientationat the times of previously identified UKS/IRM events: (1) the average magnetosheath magnetic field orientation in the 30-min period adjacent to the nearest magnetopause crossing, (2) the magnetosheath magnetic field orientation observed just outside the magnetopause, and (3) the lagged interplanetary magnetic field (IMF) orientation at the time of the transient events. Whereas the results of method 2 indicate that the events tend to occur for a southward magnetosheath magnetic field, the results of methods 1 and 3 show no such tnedency. The fact that the three methods yield significantly diffeent results emphasizes the need for caution in future studies.

  18. RELATIONSHIPs among Geomagnetic storms, interplanetary shocks, magnetic clouds, and SUNSPOT NUMBER during 1995-2012

    NASA Astrophysics Data System (ADS)

    Berdichevsky, D. B.; Lepping, R. P.; Wu, C. C.

    2015-12-01

    During 1995-2012 Wind recorded 168 magnetic clouds (MCs), 197 magnetic cloud-like structures (MCLs), and 358 interplanetary (IP) shocks. Ninety four MCs and 56 MCLs had upstream shock waves. The following features are found: (i) Averages of solar wind speed, interplanetary magnetic field (IMF), duration (<Δt>), strength of Bzmin, and intensity of the associated geomagnetic storm/activity (Dstmin) for MCs with upstream shock waves (MCSHOCK) are higher (or stronger) than those averages for the MCs without upstream shock waves (MCNO-SHOCK). (ii) The <Δt> of MCSHOCK events (≈19.6 hr) is 9% longer than that for MCNO-SHOCK events (≈17.9 hr). (iii) For the MCSHOCK events, the average duration of the sheath (<ΔtSHEATH>) is 12.1 hrs. These findings could be very useful for space weather predictions, i.e. IP shocks driven by MCs are expected to arrive at Wind (or at 1 AU) about ~12 hours ahead of the front of the MCs on average. (iv) The occurrence frequency of IP shocks is well associated with sunspot number (SSN). The average intensity of geomagnetic storms measured by for MCSHOCK and MCNOSHOCK events is -102 and -31 nT, respectively. The is -78, -70, and -35 nT for the 358 IP shocks, 168 MCs, and 197 MCLs, respectively. These results imply that IP shocks, when they occur with MCs/MCLs, must play an important role in the strength of geomagnetic storms. We speculate as to why this is so. Yearly occurrence frequencies of MCSHOCK and IP shocks are well correlated with solar activity (e.g., SSN). Choosing the right Dstmin estimating formula for predicting the intensity of MC-associated geomagnetic storms is crucial for space weather predictions.

  19. The large-scale magnetic field in the solar wind. [astronomical models of interplanetary magnetics and the solar magnetic field

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Ness, N. F.

    1976-01-01

    A literature review is presented of theoretical models of the interaction of the solar wind and interplanetary magnetic fields. Observations of interplanetary magnetic fields by the IMP and OSO spacecraft are discussed. The causes for cosmic ray variations (Forbush decreases) by the solar wind are examined. The model of Parker is emphasized. This model shows the three dimensional magnetic field lines of the solar wind to have the form of spirals wrapped on cones. It is concluded that an out-of-the-ecliptic solar probe mission would allow the testing and verification of the various theoretical models examined. Diagrams of the various models are shown.

  20. Evolution of magnetic flux ropes associated with flux transfer events and interplanetary magnetic clouds

    NASA Technical Reports Server (NTRS)

    Wei, C. Q.; Lee, L. C.; Wang, S.; Akasofu, S.-I.

    1991-01-01

    Spacecraft observations suggest that flux transfer events and interplanetary magnetic clouds may be associated with magnetic flux ropes which are magnetic flux tubes containing helical magnetic field lines. In the magnetic flux ropes, the azimuthal magnetic field is superposed on the axial field. The time evolution of a localized magnetic flux rope is studied. A two-dimensional compressible MHD simulation code with a cylindrical symmetry is developed to study the wave modes associated with the evolution of flux ropes. It is found that in the initial phase both the fast magnetosonic wave and the Alfven wave are developed in the flux rope. After this initial phase, the Alfven wave becomes the dominant wave mode for the evolution of the magnetic flux rope and the radial expansion velocity of the flux rope is found to be negligible. Numerical results further show that even for a large initial azimuthal component of the magnetic field, the propagation velocity along the axial direction of the flux rope remains the Alfven velocity. It is also found that the localized magnetic flux rope tends to evolve into two separate magnetic ropes propagating in opposite directions. The simulation results are used to study the evolution of magnetic flux ropes associated with flux transfer events observed at the earth's dayside magnetopause and magnetic clouds in the interplanetary space.

  1. The Bastille Day Magnetic Clouds and Upstream Shocks: Near Earth Interplanetary Observations

    NASA Technical Reports Server (NTRS)

    Lepping, R. P.; Berdichevsky, D. B.; Burlaga, L. F.; Lazarus, A. J.; Kasper, J.; Desch, M. D.; Wu, C.-C.; Reames, D. V.; Singer, H. J.; Singer, H. J.; hide

    2001-01-01

    The energetic charged particle, interplanetary magnetic field, and plasma characteristics of the 'Bastille Day' shock and ejecta/magnetic cloud events at 1 AU occurring over the days 14-16 July 2000 are described. Profiles of MeV (WIND/LEMT) energetic ions help to organize the overall sequence of events from the solar source to 1 AU. Stressed are analyses of an outstanding magnetic cloud (MC2) starting late on 15 July and its upstream shock about 4 hours earlier in WIND magnetic field and plasma data. Also analyzed is a less certain, but likely, magnetic cloud (MC1) occurring early on 15 July; this was separated from MC2 by its upstream shock and many heliospheric current sheet (HCS) crossings. Other HCS crossings occurred throughout the 3-day period. Overall this dramatic series of interplanetary events caused a large multi-phase magnetic storm with min Dst lower than -300 nT. The very fast solar wind speed (greater than or equal to 1100 km/s) in and around the front of MC2 (for near average densities) was responsible for a very high solar wind ram pressure driving in the front of the magnetosphere to geocentric distances estimated to be as low as approx. 5 R(sub E), much lower than the geosynchronous orbit radius. This was consistent with magnetic field observations from two GOES satellites which indicated they were in the magnetosheath for extended times. A static force free field model is used to fit the two magnetic cloud profiles providing estimates of the clouds' physical and geometrical properties. MC2 was much larger than MCI, but their axes were nearly antiparallel, and their magnetic fields had the same left-handed helicity. MC2's axis and its upstream shock normal were very close to being perpendicular to each other, as might be expected if the cloud were driving the shock at the time of observation. The estimated axial magnetic flux carried by MC2 was 52 x 10(exp 20) Mx, which is about 5 times the typical magnetic flux estimated for other magnetic

  2. Interplanetary medium data book

    NASA Technical Reports Server (NTRS)

    King, J. H.

    1977-01-01

    Unresolved questions on the physics of solar wind and its effects on magnetospheric processes and cosmic ray propagation were addressed with hourly averaged interplanetary plasma and magnetic field data. This composite data set is described with its content and extent, sources, limits of validity, and the mutual consistency studies and normalizations to which the input data were subjected. Hourly averaged parameters were presented in the form of digital listings and 27-day plots. The listings are contained in a separately bound appendix.

  3. Interplanetary magnetic field control of the Mars bow shock: Evidence for Venuslike interaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, T.L.; Schwingenschuh, K.; Lichtenegger, H.

    1991-07-01

    The Mars bow shock location and shape have been determined by examining the PHOBOS spacecraft magnetometer data. Observations show that the position of the terminator bow shock varies with interplanetary magnetic field orientation in the same way as at Venus. The shock is farthest from Mars in the direction of the interplanetary electric field, consistent with the idea that mass loading plays an important role in the solar wind interaction with Mars. The authors also find that the shock cross section at the terminator plane is asymmetric and is controlled by the interplanetary magnetic field as expected from the asymmetricmore » propagation velocity of the fast magnetosonic wave. Comparing with earlier mission data, they show that the Mars shock location varies with solar activity. The shock is farther from Mars during solar maximum. Thus the solar wind interaction with Mars appears to be Venuslike, with a magnetic moment too small to affect significantly the solar wind interaction.« less

  4. Magnetic Flux Circulation During Dawn-Dusk Oriented Interplanetary Magnetic Field

    NASA Technical Reports Server (NTRS)

    Mitchell, E. J.; Lopez, R. E.; Fok, M.-C.; Deng, Y.; Wiltberger, M.; Lyon, J.

    2010-01-01

    Magnetic flux circulation is a primary mode of energy transfer from the solar wind into the ionosphere and inner magnetosphere. For southward interplanetary magnetic field (IMF), magnetic flux circulation is described by the Dungey cycle (dayside merging, night side reconnection, and magnetospheric convection), and both the ionosphere and inner magnetosphere receive energy. For dawn-dusk oriented IMF, magnetic flux circulation is not well understood, and the inner magnetosphere does not receive energy. Several models have been suggested for possible reconnection patterns; the general pattern is: dayside merging; reconnection on the dayside or along the dawn/dusk regions; and, return flow on dayside only. These models are consistent with the lack of energy in the inner magnetosphere. We will present evidence that the Dungey cycle does not explain the energy transfer during dawn-dusk oriented IMF. We will also present evidence of how magnetic flux does circulate during dawn-dusk oriented IMF, specifically how the magnetic flux reconnects and circulates back.

  5. Interplanetary magnetic flux - Measurement and balance

    NASA Technical Reports Server (NTRS)

    Mccomas, D. J.; Gosling, J. T.; Phillips, J. L.

    1992-01-01

    A new method for determining the approximate amount of magnetic flux in various solar wind structures in the ecliptic (and solar rotation) plane is developed using single-spacecraft measurements in interplanetary space and making certain simplifying assumptions. The method removes the effect of solar wind velocity variations and can be applied to specific, limited-extent solar wind structures as well as to long-term variations. Over the 18-month interval studied, the ecliptic plane flux of coronal mass ejections was determined to be about 4 times greater than that of HFDs.

  6. Are Polar Field Magnetic Flux Concentrations Responsible for Missing Interplanetary Flux?

    NASA Astrophysics Data System (ADS)

    Linker, Jon A.; Downs, C.; Mikic, Z.; Riley, P.; Henney, C. J.; Arge, C. N.

    2012-05-01

    Magnetohydrodynamic (MHD) simulations are now routinely used to produce models of the solar corona and inner heliosphere for specific time periods. These models typically use magnetic maps of the photospheric magnetic field built up over a solar rotation, available from a number of ground-based and space-based solar observatories. The line-of-sight field at the Sun's poles is poorly observed, and the polar fields in these maps are filled with a variety of interpolation/extrapolation techniques. These models have been found to frequently underestimate the interplanetary magnetic flux (Riley et al., 2012, in press, Stevens et al., 2012, in press) near the minimum part of the cycle unless mitigating correction factors are applied. Hinode SOT observations indicate that strong concentrations of magnetic flux may be present at the poles (Tsuneta et al. 2008). The ADAPT flux evolution model (Arge et al. 2010) also predicts the appearance of such concentrations. In this paper, we explore the possibility that these flux concentrations may account for a significant amount of magnetic flux and alleviate discrepancies in interplanetary magnetic flux predictions. Research supported by AFOSR, NASA, and NSF.

  7. Effects of interplanetary magnetic clouds, interaction regions, and high-speed streams on the transient modulation of galactic cosmic rays

    NASA Astrophysics Data System (ADS)

    Singh, Y. P.; Badruddin

    2007-02-01

    Interplanetary manifestations of coronal mass ejections (CMEs) with specific plasma and field properties, called ``interplanetary magnetic clouds,'' have been observed in the heliosphere since the mid-1960s. Depending on their associated features, a set of observed magnetic clouds identified at 1 AU were grouped in four different classes using data over 4 decades: (1) interplanetary magnetic clouds moving with the ambient solar wind (MC structure), (2) magnetic clouds moving faster than the ambient solar wind and forming a shock/sheath structure of compressed plasma and field ahead of it (SMC structure), (3) magnetic clouds ``pushed'' by the high-speed streams from behind, forming an interaction region between the two (MIH structure), and (4) shock-associated magnetic clouds followed by high-speed streams (SMH structure). This classification into different groups led us to study the role, effect, and the relative importance of (1) closed field magnetic cloud structure with low field variance, (2) interplanetary shock and magnetically turbulent sheath region, (3) interaction region with large field variance, and (4) the high-speed solar wind stream coming from the open field regions, in modulating the galactic cosmic rays (GCRs). MC structures are responsible for transient decrease with fast recovery. SMC structures are responsible for fast decrease and slow recovery, MIH structures produce depression with slow decrease and slow recovery, and SMH structures are responsible for fast decrease with very slow recovery. Simultaneous variations of GCR intensity, solar plasma velocity, interplanetary magnetic field strength, and its variance led us to study the relative effectiveness of different structures as well as interplanetary plasma/field parameters. Possible role of the magnetic field, its topology, field turbulence, and the high-speed streams in influencing the amplitude and time profile of resulting decreases in GCR intensity have also been discussed.

  8. Fractal structure of the interplanetary magnetic field

    NASA Technical Reports Server (NTRS)

    Burlaga, L. F.; Klein, L. W.

    1985-01-01

    Under some conditions, time series of the interplanetary magnetic field strength and components have the properties of fractal curves. Magnetic field measurements made near 8.5 AU by Voyager 2 from June 5 to August 24, 1981 were self-similar over time scales from approximately 20 sec to approximately 3 x 100,000 sec, and the fractal dimension of the time series of the strength and components of the magnetic field was D = 5/3, corresponding to a power spectrum P(f) approximately f sup -5/3. Since the Kolmogorov spectrum for homogeneous, isotropic, stationary turbulence is also f sup -5/3, the Voyager 2 measurements are consistent with the observation of an inertial range of turbulence extending over approximately four decades in frequency. Interaction regions probably contributed most of the power in this interval. As an example, one interaction region is discussed in which the magnetic field had a fractal dimension D = 5/3.

  9. On the twists of interplanetary magnetic flux ropes observed at 1 AU

    NASA Astrophysics Data System (ADS)

    Wang, Yuming; Zhuang, Bin; Hu, Qiang; Liu, Rui; Shen, Chenglong; Chi, Yutian

    2016-10-01

    Magnetic flux ropes (MFRs) are one kind of fundamental structures in the solar/space physics and involved in various eruption phenomena. Twist, characterizing how the magnetic field lines wind around a main axis, is an intrinsic property of MFRs, closely related to the magnetic free energy and stableness. Although the effect of the twist on the behavior of MFRs had been widely studied in observations, theory, modeling, and numerical simulations, it is still unclear how much amount of twist is carried by MFRs in the solar atmosphere and in heliosphere and what role the twist played in the eruptions of MFRs. Contrasting to the solar MFRs, there are lots of in situ measurements of magnetic clouds (MCs), the large-scale MFRs in interplanetary space, providing some important information of the twist of MFRs. Thus, starting from MCs, we investigate the twist of interplanetary MFRs with the aid of a velocity-modified uniform-twist force-free flux rope model. It is found that most of MCs can be roughly fitted by the model and nearly half of them can be fitted fairly well though the derived twist is probably overestimated by a factor of 2.5. By applying the model to 115 MCs observed at 1 AU, we find that (1) the twist angles of interplanetary MFRs generally follow a trend of about 0.6l/R radians, where l/R is the aspect ratio of a MFR, with a cutoff at about 12π radians AU-1, (2) most of them are significantly larger than 2.5π radians but well bounded by 2l/R radians, (3) strongly twisted magnetic field lines probably limit the expansion and size of MFRs, and (4) the magnetic field lines in the legs wind more tightly than those in the leading part of MFRs. These results not only advance our understanding of the properties and behavior of interplanetary MFRs but also shed light on the formation and eruption of MFRs in the solar atmosphere. A discussion about the twist and stableness of solar MFRs are therefore given.

  10. Numerical Simulation on a Possible Formation Mechanism of Interplanetary Magnetic Cloud Boundaries

    NASA Astrophysics Data System (ADS)

    Fan, Quan-Lin; Wei, Feng-Si; Feng, Xue-Shang

    2003-08-01

    The formation mechanism of the interplanetary magnetic cloud (MC) boundaries is numerically investigated by simulating the interactions between an MC of some initial momentum and a local interplanetary current sheet. The compressible 2.5D MHD equations are solved. Results show that the magnetic reconnection process is a possible formation mechanism when an MC interacts with a surrounding current sheet. A number of interesting features are found. For instance, the front boundary of the MCs is a magnetic reconnection boundary that could be caused by a driven reconnection ahead of the cloud, and the tail boundary might be caused by the driving of the entrained flow as a result of the Bernoulli principle. Analysis of the magnetic field and plasma data demonstrates that at these two boundaries appear large value of the plasma parameter β, clear increase of plasma temperature and density, distinct decrease of magnetic magnitude, and a transition of magnetic field direction of about 180 degrees. The outcome of the present simulation agrees qualitatively with the observational results on MC boundary inferred from IMP-8, etc. The project supported by National Natural Science Foundation of China under Grant Nos. 40104006, 49925412, and 49990450

  11. Counterstreaming electrons in small interplanetary magnetic flux ropes

    NASA Astrophysics Data System (ADS)

    Feng, H. Q.; Zhao, G. Q.; Wang, J. M.

    2015-12-01

    Small interplanetary magnetic flux ropes (SIMFRs) are commonly observed by spacecraft at 1 AU, and their origin still remains disputed. We investigated the counterstreaming suprathermal electron (CSE) signatures of 106 SIMFRs measured by Wind during 1995-2005. We found that 79 (75%) of the 106 flux ropes contain CSEs, and the percentages of counterstreaming vary from 8% to 98%, with a mean value of 51%. CSEs are often observed in magnetic clouds (MCs), and this indicates these MCs are still attached to the Sun at both ends. CSEs are also related to heliospheric current sheets (HCSs) and the Earth's bow shock. We divided the SIMFRs into two categories: The first category is far from HCSs, and the second category is in the vicinity of HCSs. The first category has 57 SIMFRs, and only 7 of 57 ropes have no CSEs. This ratio is similar to that of MCs. The second category has 49 SIMFRs; however, 20 of the 49 events have no CSEs. This ratio is larger than that of MCs. These two categories have different origins. One category originates from the solar corona, and most ropes are still connected to the Sun at both ends. The other category is formed near HCSs in the interplanetary space.

  12. Non-Gaussianity and cross-scale coupling in interplanetary magnetic field turbulence during a rope-rope magnetic reconnection event

    NASA Astrophysics Data System (ADS)

    Miranda, Rodrigo A.; Schelin, Adriane B.; Chian, Abraham C.-L.; Ferreira, José L.

    2018-03-01

    In a recent paper (Chian et al., 2016) it was shown that magnetic reconnection at the interface region between two magnetic flux ropes is responsible for the genesis of interplanetary intermittent turbulence. The normalized third-order moment (skewness) and the normalized fourth-order moment (kurtosis) display a quadratic relation with a parabolic shape that is commonly observed in observational data from turbulence in fluids and plasmas, and is linked to non-Gaussian fluctuations due to coherent structures. In this paper we perform a detailed study of the relation between the skewness and the kurtosis of the modulus of the magnetic field |B| during a triple interplanetary magnetic flux rope event. In addition, we investigate the skewness-kurtosis relation of two-point differences of |B| for the same event. The parabolic relation displays scale dependence and is found to be enhanced during magnetic reconnection, rendering support for the generation of non-Gaussian coherent structures via rope-rope magnetic reconnection. Our results also indicate that a direct coupling between the scales of magnetic flux ropes and the scales within the inertial subrange occurs in the solar wind.

  13. The topology of intrasector reversals of the interplanetary magnetic field

    NASA Astrophysics Data System (ADS)

    Kahler, S. W.; Crooker, N. U.; Gosling, J. T.

    1996-11-01

    A technique has been developed recently to determine the polarities of interplanetary magnetic fields relative to their origins at the Sun by comparing energetic electron flow directions with local magnetic field directions. Here we use heat flux electrons from the Los Alamos National Laboratory (LANL) plasma detector on the ISEE 3 spacecraft to determine the field polarities. We examine periods within well-defined magnetic sectors when the field directions appear to be reversed from the normal spiral direction of the sector. About half of these intrasector field reversals (IFRs) are cases in which the polarities match those of the surrounding sectors, indicating that those fields have been folded back toward the Sun. The more interesting cases are those with polarity reversals. We find no clear cases of isolated reverse polarity fields, which suggests that islands of reverse polarity in the solar source dipole field probably do not exist. The IFRs with polarity reversals are strongly associated with periods of bidirectional electron flows, suggesting that those fields occur only in conjunction with closed fields. We propose that both those IFRs and the bidirectional flows are signatures of coronal mass ejections (CMEs). In that case, many interplanetary CMEs are larger and more complex than previously thought, consisting of both open and closed field components.

  14. The relation of variations in total magnetic field at high latitude with the parameters of the interplanetary magnetic field and with DP2 fluctuations. [using OGO -3-C, and -4 observations

    NASA Technical Reports Server (NTRS)

    Langel, R. A.

    1974-01-01

    The maximum disturbances from the positive and negative regions of delta B (Bp and Bn, respectively) are investigated with respect to their correlation with (1) the average N-S component, Bz, (2) the average angle with respect to the solar magnetospheric equatorial plane, theta (3) the variance, sigma sub i, and (4) the magnitude, Bi, of the interplanetary magnetic field. These quantities were averaged over a period, T, ranging from 20 min. to 8 hours prior to the measurement of Bp or Bn. Variations (i.e., disturbances) in total magnetic field magnitude were studied utilizing data from the Polar Orbiting Geophysical Observatory satellites (OGO 2, 4, and 6), unofficially referred to as POGO.

  15. Magnetic flux rope versus the spheromak as models for interplanetary magnetic clouds

    NASA Technical Reports Server (NTRS)

    Farrugia, C. J.; Osherovich, V. A.; Burlaga, L. F.

    1995-01-01

    Magnetic clouds form a subset of interplanetary ejecta with well-defined magnetic and thermodynamic properties. Observationally, it is well established that magnetic clouds expand as they propagate antisunward. The aim of this paper is to compare and contrast two models which have been proposed for the global magnetic field line topology of magnetic clouds: a magnetic flux tube geometry, on the one hand, and a spheromak geometry (including possible higher multiples), on the other. Traditionally, the magnetic structure of magnetic clouds has been modeled by force-free configurations. In a first step, we therefore analyze the ability of static force-free models to account for the asymmetries observed in the magnetic field profiles of magnetic clouds. For a cylindrical flux tube the magnetic field remains symmetric about closest approach to the magnetic axis on all spacecraft orbits intersecting it, whereas in a spheromak geometry one can have asymmetries in the magnetic field signatures along some spacecraft trajectories. The duration of typical magnetic cloud encounters at 1 AU (1 to 2 days) is comparable to their travel time from the Sun to 1 AU and thus magnetic clouds should be treated as strongly nonstationary objects. In a second step, therefore, we abandon the static approach and model magnetic clouds as self-similarly evolving MHD configurations. In our theory, the interaction of the expanding magnetic cloud with the ambient plasma is taken into account by a drag force proportional to the density and the velocity of expansion. Solving rigorously the full set of MHD equations, we demonstrate that the asymmetry in the magnetic signature may arise solely as a result of expansion. Using asymptotic solutions of the MHD equations, we least squares fit both theoretical models to interplanetary data. We find that while the central part of the magnetic cloud is adequately described by both models, the 'edges' of the cloud data are modeled better by the magnetic flux

  16. Interplanetary Magnetic Field and Plasma Values Related to Hildcaas Events

    NASA Astrophysics Data System (ADS)

    Prestes, A.; Serra, S. L.; Vieira, L. A.

    2013-05-01

    In this work we investigate the interplanetary conditions during the occurrence of 150 HILDCAAs/QUASI-HILDCAAs events occurred between 1998 and 2007. These events were chosen by following strictly the selection criteria for this kind of phenomena and with some criteria flexible. Among the criteria used to characterize events HILDCAAs, the criterion that considers "the AE values never dropped below 200 nT for more than 2 h at a time" was more restrictive, thus only this was modified by changing from 2 to 4 hours the period in which the AE value can't be below 200 nT. In the interplanetary medium, HILDCAAs are associated with high speed solar wind streams, which are frequently embedded with alfvénic fluctuations. At the Sun, these high speed streams are originated in coronal holes. The distribution of events HILDCAAs/quasi-HILDCAAs along the solar cycle shows a pattern of double peak, a less intense around the maximum of the sunspot cycle and other intense in the descending phase, similar to the distribution of low-latitude coronal holes. For each one of the selected events we have found the most probable value of interplanetary magnetic field and plasma. The average values of AE, AU, AL and Dst indices, the density and temperature of the solar wind protons, the solar wind speed, the Bz component of the IMF, the IMF intensity, dynamic pressure and factor beta, among all the 150 events HILDCAAs/quasi-HILDCAAs, were: AE (344.5 ± 65.0 nT), AU (131.0 ± 33.0 nT), AL (-213.7 ± 51.2 nT), Dst (-25.8 ± 12.2 nT), Density (5,0 ± 1,8 cm-3), Temperature (151269.5 ± 48907.7 K), |V| (538.2 ± 83.3 km/s) Bz (-0.71 ± 1.02 nT), |B| (6.7 ± 1.4 nT) pressure (2.6 ± 0.7 nPa) and Beta (0.66 ± 0.27).

  17. Structure of magnetopause layers formed by a radial interplanetary magnetic field

    NASA Astrophysics Data System (ADS)

    Safrankova, Jana; Simunek, Jiri; Nemecek, Zdenek; Prech, Lubomir; Grygorov, Kostiantyn; Shue, Jih-Hong; Samsonov, Andrey; Pi, Gilbert

    2016-07-01

    The magnetopause location is generally believed to be determined by the solar wind dynamic pressure and by the sign and value of the interplanetary magnetic field (IMF) vertical (Bz) component. A contribution of other parameters is usually assumed to be minor or negligible near the equatorial plane. However, recent papers have shown a magnetopause expansion during intervals of a nearly radial IMF (large IMF Bx component). Under such conditions, the total pressure exerted on the subsolar magnetopause is significantly lower than the solar wind dynamic pressure as demonstrate both MHD simulations and statistical investigations. During a long-duration radial IMF, all parameters - the IMF magnitude, solar wind speed, density, and especially the temperature are depressed in comparison with their yearly averages. Moreover, in this case, the structures of the LLBL change; the LLBL shows different profiles at both hemispheres for negative and positive IMF Bx polarities. This asymmetry changes over time and influences the LLBL structures due to magnetic reconnection. We present an overview of important physical quantities controlling the magnetopause compression and new results that deal with the structure of the magnetopause and adjacent layers.

  18. Strong ionospheric field-aligned currents for radial interplanetary magnetic fields

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Lühr, Hermann; Shue, Jih-Hong; Frey, Harald. U.; Kervalishvili, Guram; Huang, Tao; Cao, Xue; Pi, Gilbert; Ridley, Aaron J.

    2014-05-01

    The present work has investigated the configuration of field-aligned currents (FACs) during a long period of radial interplanetary magnetic field (IMF) on 19 May 2002 by using high-resolution and precise vector magnetic field measurements of CHAMP satellite. During the interest period IMF By and Bz are weakly positive and Bx keeps pointing to the Earth for almost 10 h. The geomagnetic indices Dst is about -40 nT and AE about 100 nT on average. The cross polar cap potential calculated from Assimilative Mapping of Ionospheric Electrodynamics and derived from DMSP observations have average values of 10-20 kV. Obvious hemispheric differences are shown in the configurations of FACs on the dayside and nightside. At the south pole FACs diminish in intensity to magnitudes of about 0.1 μA/m2, the plasma convection maintains two-cell flow pattern, and the thermospheric density is quite low. However, there are obvious activities in the northern cusp region. One pair of FACs with a downward leg toward the pole and upward leg on the equatorward side emerge in the northern cusp region, exhibiting opposite polarity to FACs typical for duskward IMF orientation. An obvious sunward plasma flow channel persists during the whole period. These ionospheric features might be manifestations of an efficient magnetic reconnection process occurring in the northern magnetospheric flanks at high latitude. The enhanced ionospheric current systems might deposit large amount of Joule heating into the thermosphere. The air densities in the cusp region get enhanced and subsequently propagate equatorward on the dayside. Although geomagnetic indices during the radial IMF indicate low-level activity, the present study demonstrates that there are prevailing energy inputs from the magnetosphere to both the ionosphere and thermosphere in the northern polar cusp region.

  19. Low energy proton bidirectional anisotropies and their relation to transient interplanetary magnetic structures: ISEE-3 observations

    NASA Technical Reports Server (NTRS)

    Marsden, R. G.; Sanderson, T. R.; Wenzel, K. P.; Smith, E. J.

    1985-01-01

    It is known that the interplanetary medium in the period approaching solar maximum is characterized by an enhancement in the occurrence of transient solar wind streams and shocks and that such systems are often associated with looplike magnetic structures or clouds. There is observational evidence that bidirectional, field aligned flows of low energy particles could be a signature of such looplike structures, although detailed models for the magnetic field configuration and injection mechanisms do not exist at the current time. Preliminary results of a survey of low energy proton bidirectional anisotropies measured on ISEE-3 in the interplanetary medium between August 1978 and May 1982, together with magnetic field data from the same spacecraft are presented.

  20. Interplanetary Magnetic Flux Ropes as Agents Connecting Solar Eruptions and Geomagnetic Activities

    NASA Astrophysics Data System (ADS)

    Marubashi, K.; Cho, K.-S.; Ishibashi, H.

    2017-12-01

    We investigate the solar wind structure for 11 cases that were selected for the campaign study promoted by the International Study of Earth-affecting Solar Transients (ISEST) MiniMax24 Working Group 4. We can identify clear flux rope signatures in nine cases. The geometries of the nine interplanetary magnetic flux ropes (IFRs) are examined with a model-fitting analysis with cylindrical and toroidal force-free flux rope models. For seven cases in which magnetic fields in the solar source regions were observed, we compare the IFR geometries with magnetic structures in their solar source regions. As a result, we can confirm the coincidence between the IFR orientation and the orientation of the magnetic polarity inversion line (PIL) for six cases, as well as the so-called helicity rule as regards the handedness of the magnetic chirality of the IFR, depending on which hemisphere of the Sun the IFR originated from, the northern or southern hemisphere; namely, the IFR has right-handed (left-handed) magnetic chirality when it is formed in the southern (northern) hemisphere of the Sun. The relationship between the orientation of IFRs and PILs can be taken as evidence that the flux rope structure created in the corona is in most cases carried through interplanetary space with its orientation maintained. In order to predict magnetic field variations on Earth from observations of solar eruptions, further studies are needed about the propagation of IFRs because magnetic fields observed at Earth significantly change depending on which part of the IFR hits the Earth.

  1. The effects of interplanetary magnetic field orientation on dayside high-latitude ionospheric convection

    NASA Technical Reports Server (NTRS)

    Heelis, R. A.

    1984-01-01

    The Atmosphere Explorer C data base of Northern Hemisphere ionospheric convection signatures at high latitudes is examined during times when the interplanetary magnetic field orientation is relatively stable. It is found that when the interplanetary magnetic field (IMF) has its expected garden hose orientation, the center of a region where the ion flow rotates from sunward to antisunward is displaced from local noon toward dawn irrespective of the sign of By. Poleward of this rotation region, called the cleft, the ion convection is directed toward dawn or dusk depending on whether By is positive or negative, respectively. The observed flow geometry can be explained in terms of a magnetosphere solar wind interaction in which merging is favored in either the prenoon Northern Hemisphere or the prenoon Southern Hemisphere when the IMF has a normal sector structure that is toward or away, respectively.

  2. The Polar Ionosphere and Interplanetary Field.

    DTIC Science & Technology

    1987-08-01

    model for investigating time dependent behavior of the Polar F-region ionosphere in response to varying interplanetary magnetic field (IMF...conditions. The model has been used to illustrate ionospheric behavior during geomagnetic storms conditions. Future model applications may include...magnetosphere model for investigating time dependent behavior of the polar F-region ionosphere in response to varying interplanetary magnetic field

  3. Magnetic field directional discontinuities. 2: Characteristics between 0.46 and 1.0 AU. [interplanetary magnetic fields

    NASA Technical Reports Server (NTRS)

    Lepping, R. P.; Benhannon, K. W.

    1980-01-01

    The characteristics of directional discontinuities (DD's) in the interplanetary magnetic field are studied using data from the Mariner 10 primary mission between 1.0 and 0.46 AU. Statistical and visual survey methods for DD identification resulted in a total of 644 events. Two methods were used to estimate the ratio of the number of tangential discontinuities (TD's) to the number of rotational discontinuities (RD's). Both methods show that the ratio of TD's to RD's varied with time and decreased with decreasing radial distance. A decrease in average discontinuity thickness of approx. 40 percent was found between 1.0 and 0.72 AU and approx. 54 percent between 1.0 and 0.46 AU, independent of type (TD or RD). This decrease in thickness for decreasing r is in qualitative agreement with Pioneer 10 observations between 1 and 5 AU. When the individual DD thickness are normalized with respect to the estimated local proton gyroradius (RA sub L), the average thickness at the three locations is nearly constant, 43 + or - 6 R sub L. This also holds true for both RD's and TD's separately. Statistical distributions of other properties, such as normal components and discontinuity plane angles, are presented.

  4. ISEE 3 observations of low-energy proton bidirectional events and their relation to isolated interplanetary magnetic structures

    NASA Technical Reports Server (NTRS)

    Marsden, R. G.; Sanderson, T. R.; Tranquille, C.; Wenzel, K.-P.; Smith, E. J.

    1987-01-01

    The paper represents the results of a comprehensive survey of low-energy proton bidirectional anisotropies and associated transient magnetic structures as observed in the 35-1600 keV energy range on ISEE-3 during the last solar maximum. The majority of observed bidirectional flow (BDF) events (more than 70 percent) are associated with isolated magnetic structures which are postulated to be an interplanetary manifestation of coronal mass ejection (CME) events. The observed BDF events can be qualitatively grouped into five classes depending on the field signature of the related magnetic structure and the association (or lack of association) with an interplanetary shock. Concerning the topology of the CME-related magnetic structures, the observations are interpreted as being consistent with a detached bubble, comprising closed loops or tightly wound helices.

  5. Analysis of the interplanetary magnetic field observations at different heliocentric distances

    NASA Astrophysics Data System (ADS)

    Khabarova, Olga

    2013-04-01

    Multi-spacecraft measurements of the interplanetary magnetic field (IMF) from 0.29 AU to 5 AU along the ecliptic plane have demonstrated systematic deviations of the observed IMF strength from the values predicted on the basis of the Parker-like radial extension models (Khabarova, Obridko, 2012). In particular, it was found that the radial IMF component |Br| decreases with a heliocentric distance r with a slope of -5/3 (instead of r-2 expansion law). The current investigation of multi-point observations continues the analysis of the IMF (and, especially, Br) large-scale behaviour, including its latitudinal distribution. Additionally, examples of the mismatches between the expected IMF characteristics and observations at smaller scales are discussed. It is shown that the observed effects may be explained by not complete IMF freezing-in to the solar wind plasma. This research was supported by the Russian Fund of Basic Researches' grants Nos.11-02-00259-a, and 12-02-10008-K. Khabarova Olga, and Obridko Vladimir, Puzzles of the Interplanetary Magnetic Field in the Inner Heliosphere, 2012, Astrophysical Journal, 761, 2, 82, doi:10.1088/0004-637X/761/2/82, http://arxiv.org/pdf/1204.6672v2.pdf

  6. Interplanetary field and plasma during initial phase of geomagnetic storms

    NASA Technical Reports Server (NTRS)

    Patel, V. L.; Wiskerchen, M. J.

    1975-01-01

    A study has been conducted of a large number of geomagnetic storms occurring during the period from 1966 to 1970. Questions of data selection are discussed and the large-scale interplanetary magnetic field during the initial phase is examined. Small-scale interplanetary fields during the initial phase are also considered, taking into account important features of small-scale variations in the interplanetary field and plasma for three storms. Details concerning 23 geomagnetic storms and the interplanetary magnetic field are presented in a table. A study of the initial phase of these storms indicates that in most of these events, the solar-ecliptic Z component of the interplanetary magnetic field turns southward when the main phase decrease begins.

  7. Influence of interplanetary magnetic field and solar wind on auroral brightness in different regions

    NASA Astrophysics Data System (ADS)

    Yang, Y. F.; Lu, J. Y.; Wang, J.-S.; Peng, Z.; Zhou, L.

    2013-01-01

    Abstract<p label="1">By integrating and <span class="hlt">averaging</span> the auroral brightness from Polar Ultraviolet Imager auroral images, which have the whole auroral ovals, and combining the observation data of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) and solar wind from NASA Operating Missions as a Node on the Internet (OMNI), we investigate the influence of IMF and solar wind on auroral activities, and analyze the separate roles of the solar wind dynamic pressure, density, and velocity on aurora, respectively. We statistically analyze the relations between the <span class="hlt">interplanetary</span> conditions and the auroral brightness in dawnside, dayside, duskside, and nightside. It is found that the three components of the IMF have different effects on the auroral brightness in the different regions. Different from the nightside auroral brightness, the dawnside, dayside, and duskside auroral brightness are affected by the IMF Bx, and By components more significantly. The IMF Bx and By components have different effects on these three regional auroral brightness under the opposite polarities of the IMF Bz. As expected, the nightside aurora is mainly affected by the IMF Bz, and under southward IMF, the larger the |Bz|, the brighter the nightside aurora. The IMF Bx and By components have no visible effects. On the other hand, it is also found that the aurora is not intensified singly with the increase of the solar wind dynamic pressure: when only the dynamic pressure is high, but the solar wind velocity is not very fast, the aurora will not necessarily be intensified significantly. These results can be used to qualitatively predict the auroral activities in different regions for various <span class="hlt">interplanetary</span> conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20180000655&hterms=jupiter&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Djupiter','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20180000655&hterms=jupiter&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Djupiter"><span>The <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Observed by Juno Enroute to Jupiter</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gruesbeck, Jacob R.; Gershman, Daniel J.; Espley, Jared R.; Connerney, John E. P.</p> <p>2017-01-01</p> <p>The Juno spacecraft was launched on 5 August 2011 and spent nearly 5 years traveling through the inner heliosphere on its way to Jupiter. The <span class="hlt">Magnetic</span> Field Investigation was powered on shortly after launch and obtained vector measurements of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) at sample rates from 1 to 64 samples/second. The evolution of the <span class="hlt">magnetic</span> field with radial distance from the Sun is compared to similar observations obtained by Voyager 1 and 2 and the Ulysses spacecraft, allowing a comparison of the radial evolution between prior solar cycles and the current depressed one. During the current solar cycle, the strength of the IMF has decreased throughout the inner heliosphere. A comparison of the variance of the normal component of the <span class="hlt">magnetic</span> field shows that near Earth the variability of the IMF is similar during all three solar cycles but may be less at greater radial distances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760053286&hterms=formation+day+night&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dformation%2Bday%2Bnight','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760053286&hterms=formation+day+night&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dformation%2Bday%2Bnight"><span>Influence of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field on the occurrence and thickness of the plasma mantle</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sckopke, N.; Paschmann, G.; Rosenbauer, H.; Fairfield, D. H.</p> <p>1976-01-01</p> <p>The response of the plasma mantle to the orientation of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) has been studied by correlating Heos 2 plasma and Imp 6 <span class="hlt">magnetic</span> field data. The mantle is nearly always present when the IMF has a southward component and often also when the field has a weak northward component. In addition, the mantle appears increasingly thicker with greater southward components. On the other hand, the mantle is thin or missing (from the region where it is normally found) when the <span class="hlt">average</span> IMF has a strong northward component. This result supports the idea that polar cap convection plays a dominant role in the formation of the plasma mantle: mantle plasma originates in the magnetosheath, enters the magnetosphere through the day side polar cusps, and is transported across the cusp to the night side by means of a convection electric field whose magnitude is controlled by the orientation of the IMF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930053282&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D40%26Ntt%3Dlazarus','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930053282&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D40%26Ntt%3Dlazarus"><span>A study of an expanding interplanatary <span class="hlt">magnetic</span> cloud and its interaction with the earth's magnetosphere - The <span class="hlt">interplanetary</span> aspect</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Farrugia, C. J.; Burlaga, L. F.; Osherovich, V. A.; Richardson, I. G.; Freeman, M. P.; Lepping, R. P.; Lazarus, A. J.</p> <p>1993-01-01</p> <p>High time resolution <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and plasma measurements of an <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> cloud and its interaction with the earth's magnetosphere on January 14/15, 1988 are interpreted and discussed. It is argued that the data are consistent with the theoretical model of <span class="hlt">magnetic</span> clouds as flux ropes of local straight cylindrical geometry. The data also suggest that this cloud is aligned with its axis in the ecliptic plane and pointing in the east-west direction. Evidence consisting of the intensity and directional distribution of energetic particle in the <span class="hlt">magnetic</span> cloud argues in favor of the connectedness of the <span class="hlt">magnetic</span> field lines to the sun's surface. The intensities of about 0.5 MeV ions is rapidly enhanced and the particles stream in a collimated beam along the <span class="hlt">magnetic</span> field preferentially from the west of the sun. The particles travel form a flare site along the cloud <span class="hlt">magnetic</span> field lines, which are thus presumably still attached to the sun.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720018182','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720018182"><span>Precipitation of low energy electrons at high latitudes: Effects of substorms, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and dipole tilt angle</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burch, J. L.</p> <p>1972-01-01</p> <p>Data from the auroral particles experiment on OGO-4 were used to study effects of substorm activity, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field latitutde, and dipole tilt angle on high-latitude precipitation of 700 eV electrons. It was found that: (1) The high-latitude zone of 700 eV electron precipitation in late evening and early morning hours moves equatorward by 5 to 10 deg during substorms. (2) The low-latitude boundary of polar cusp electron precipitation at 9 to 15 hours MLT also moves equatorward by several degrees during substorms and, in the absence of significant substorm activity, after a period of southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. (3) With times containing substorm activity or a southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field eliminated, the low-latitude boundary of polar cusp electron precipitation is found to move by approximately 4 deg over the total yearly range of tilt angles. At maximum winter and summer conditions the invariant latitude of the boundary is shown to shift by approximately -3 deg and +1 deg respectively from its equinox location.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMSM31A1860S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMSM31A1860S"><span><span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Power Spectrum Variations: A VHO Enabled Study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Szabo, A.; Koval, A.; Merka, J.; Narock, T. W.</p> <p>2010-12-01</p> <p>The newly reprocessed high time resolution (11/22 vectors/sec) Wind mission <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field data and the solar wind key parameter search capability of the Virtual Heliospheric Observatory (VHO) affords an opportunity to study <span class="hlt">magnetic</span> field power spectral density variations as a function of solar wind conditions. In the reprocessed Wind <span class="hlt">Magnetic</span> Field Investigation (MFI) data, the spin tone and its harmonics are greatly reduced that allows the meaningful fitting of power spectra to the ~2 Hz limit above which digitization noise becomes apparent. The power spectral density is computed and the spectral index is fitted for the MHD and ion inertial regime separately along with the break point between the two for various solar wind conditions . The time periods of fixed solar wind conditions are obtained from VHO searches that greatly simplify the process. The functional dependence of the ion inertial spectral index and break point on solar wind plasma and <span class="hlt">magnetic</span> field conditions will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1304818-influences-solar-wind-pressure-interplanetary-magnetic-field-global-magnetic-field-outer-radiation-belt-electrons','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1304818-influences-solar-wind-pressure-interplanetary-magnetic-field-global-magnetic-field-outer-radiation-belt-electrons"><span>The influences of solar wind pressure and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field on global <span class="hlt">magnetic</span> field and outer radiation belt electrons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Yu, J.; Li, L. Y.; Cao, J. B.; ...</p> <p>2016-07-28</p> <p>Using the Van Allen Probe in situ measured <span class="hlt">magnetic</span> field and electron data, we examine the solar wind dynamic pressure and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) effects on global <span class="hlt">magnetic</span> field and outer radiation belt relativistic electrons (≥1.8 MeV). The dynamic pressure enhancements (>2 nPa) cause the dayside <span class="hlt">magnetic</span> field increase and the nightside <span class="hlt">magnetic</span> field reduction, whereas the large southward IMFs (B z-IMF < –2nT) mainly lead to the decrease of the nightside <span class="hlt">magnetic</span> field. In the dayside increased <span class="hlt">magnetic</span> field region (<span class="hlt">magnetic</span> local time (MLT) ~ 06:00–18:00, and L > 4), the pitch angles of relativistic electrons are mainlymore » pancake distributions with a flux peak around 90° (corresponding anisotropic index A > 0.1), and the higher-energy electrons have stronger pancake distributions (the larger A), suggesting that the compression-induced betatron accelerations enhance the dayside pancake distributions. However, in the nighttime decreased <span class="hlt">magnetic</span> field region (MLT ~ 18:00–06:00, and L ≥ 5), the pitch angles of relativistic electrons become butterfly distributions with two flux peaks around 45° and 135° (A < 0). The spatial range of the nighttime butterfly distributions is almost independent of the relativistic electron energy, but it depends on the <span class="hlt">magnetic</span> field day-night asymmetry and the <span class="hlt">interplanetary</span> conditions. The dynamic pressure enhancements can make the nighttime butterfly distribution extend inward. The large southward IMFs can also lead to the azimuthal expansion of the nighttime butterfly distributions. As a result, these variations are consistent with the drift shell splitting and/or magnetopause shadowing effect.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1304818','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1304818"><span>The influences of solar wind pressure and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field on global <span class="hlt">magnetic</span> field and outer radiation belt electrons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Yu, J.; Li, L. Y.; Cao, J. B.</p> <p></p> <p>Using the Van Allen Probe in situ measured <span class="hlt">magnetic</span> field and electron data, we examine the solar wind dynamic pressure and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) effects on global <span class="hlt">magnetic</span> field and outer radiation belt relativistic electrons (≥1.8 MeV). The dynamic pressure enhancements (>2 nPa) cause the dayside <span class="hlt">magnetic</span> field increase and the nightside <span class="hlt">magnetic</span> field reduction, whereas the large southward IMFs (B z-IMF < –2nT) mainly lead to the decrease of the nightside <span class="hlt">magnetic</span> field. In the dayside increased <span class="hlt">magnetic</span> field region (<span class="hlt">magnetic</span> local time (MLT) ~ 06:00–18:00, and L > 4), the pitch angles of relativistic electrons are mainlymore » pancake distributions with a flux peak around 90° (corresponding anisotropic index A > 0.1), and the higher-energy electrons have stronger pancake distributions (the larger A), suggesting that the compression-induced betatron accelerations enhance the dayside pancake distributions. However, in the nighttime decreased <span class="hlt">magnetic</span> field region (MLT ~ 18:00–06:00, and L ≥ 5), the pitch angles of relativistic electrons become butterfly distributions with two flux peaks around 45° and 135° (A < 0). The spatial range of the nighttime butterfly distributions is almost independent of the relativistic electron energy, but it depends on the <span class="hlt">magnetic</span> field day-night asymmetry and the <span class="hlt">interplanetary</span> conditions. The dynamic pressure enhancements can make the nighttime butterfly distribution extend inward. The large southward IMFs can also lead to the azimuthal expansion of the nighttime butterfly distributions. As a result, these variations are consistent with the drift shell splitting and/or magnetopause shadowing effect.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770060049&hterms=method+magnetic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmethod%2Bmagnetic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770060049&hterms=method+magnetic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmethod%2Bmagnetic"><span>The mean <span class="hlt">magnetic</span> field of the sun - Method of observation and relation to the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scherrer, P. H.; Wilcox, J. M.; Kotov, V.; Severnyi, A. B.; Howard, R.</p> <p>1977-01-01</p> <p>The mean solar <span class="hlt">magnetic</span> field as measured in integrated light has been observed since 1968. Since 1970 it has been observed both at Hale Observatories and at the Crimean Astrophysical Observatory. The observing procedures at both observatories and their implications for mean field measurements are discussed. A comparison of the two sets of daily observations shows that similar results are obtained at both observatories. A comparison of the mean field with the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> polarity shows that the IMF sector structure has the same pattern as the mean field polarity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19740008403','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19740008403"><span>Observations of interactions between <span class="hlt">interplanetary</span> and geomagnetic fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burch, J. L.</p> <p>1973-01-01</p> <p>Magnetospheric effects associated with variations of the north-south component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field are examined in light of recent recent experimental and theoretical results. Although the occurrence of magnetospheric substorms is statistically related to periods of southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, the details of the interaction are not understood. In particular, attempts to separate effects resulting directly from the interaction between the <span class="hlt">interplanetary</span> and geomagnetic fields from those associated with substorms have produced conflicting results. The transfer of <span class="hlt">magnetic</span> flux from the dayside to the nightside magnetosphere is evidenced by equatorward motion of the polar cusp and increases of the <span class="hlt">magnetic</span> energy density in the lobes of the geomagnetic tail. The formation of a macroscopic X-type neutral line at tail distances less than 35 R sub E appears to be a substorm phenomenon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030014815','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030014815"><span><span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Control of the Entry of Solar Energetic Particles into the Magnetosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richard, R. L.; El-Alaoui, M.; Ashour-Abdalla, M.; Walker, R. J.</p> <p>2002-01-01</p> <p>We have investigated the entry of energetic ions of solar origin into the magnetosphere as a function of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field orientation. We have modeled this entry by following high energy particles (protons and 3 He ions) ranging from 0.1 to 50 MeV in electric and <span class="hlt">magnetic</span> fields from a global magnetohydrodynamic (MHD) model of the magnetosphere and its interaction with the solar wind. For the most part these particles entered the magnetosphere on or near open field lines except for some above 10 MeV that could enter directly by crossing field lines due to their large gyroradii. The MHD simulation was driven by a series of idealized solar wind and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) conditions. It was found that the flux of particles in the magnetosphere and transport into the inner magnetosphere varied widely according to the IMF orientation for a constant upstream particle source, with the most efficient entry occurring under southward IMF conditions. The flux inside the magnetosphere could approach that in the solar wind implying that SEPs can contribute significantly to the magnetospheric energetic particle population during typical SEP events depending on the state of the magnetosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070023320&hterms=mass+fraction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmass%2Bfraction','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070023320&hterms=mass+fraction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmass%2Bfraction"><span><span class="hlt">Interplanetary</span> Coronal Mass Ejections During 1996 - 2007</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>2007-01-01</p> <p><span class="hlt">Interplanetary</span> coronal mass ejections, the <span class="hlt">interplanetary</span> counterparts of coronal mass ejections at the Sun, are the major drivers of <span class="hlt">interplanetary</span> shocks in the heliosphere, and are associated with modulations of the galactic cosmic ray intensity, both short term (Forbush decreases caused by the passage of the shock, post-shock sheath, and ICME), and possibly with longer term modulation. Using several in-situ signatures of ICMEs, including plasma temperature, and composition, <span class="hlt">magnetic</span> fields, and cosmic ray modulations, made by near-Earth spacecraft, we have compiled a "comprehensive" list of ICMEs passing the Earth since 1996, encompassing solar cycle 23. We summarize the properties of these ICMEs, such as their occurrence rate, speeds and other parameters, the fraction of ICMEs that are classic <span class="hlt">magnetic</span> clouds, and their association with solar energetic particle events, halo CMEs, <span class="hlt">interplanetary</span> shocks, geomagnetic storms, shocks and cosmic ray decreases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860056274&hterms=orbiting+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dorbiting%2Bwind','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860056274&hterms=orbiting+wind&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dorbiting%2Bwind"><span>On the use of a sunward libration-point-orbiting spacecraft as an <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field monitor for magnetospheric studies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kelly, T. J.; Crooker, N. U.; Siscoe, G. L.; Russell, C. T.; Smith, E. J.</p> <p>1986-01-01</p> <p>In order to test the accuracy of using magnetometer data from a spacecraft orbiting the sunward libration point to determine the orientation of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF), the angle between the IMF at ISEE 3, when it was positioned around the libration point, and at ISEE 1, orbiting the earth, has been calculated for a data set of 1-hour periods covering four months. For each period, a 10-minute <span class="hlt">average</span> of ISEE 1 data is compared with 10-minute <span class="hlt">averages</span> of ISEE 3 data at successively lagged intervals. It is concluded that the IMF orientation at a libration-point-orbiting spacecraft, lagged by the time required for the solar wind to convect to the earth, is a convenient predictor of IMF orientation near the earth, to within about 20-degree accuracy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123..272W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123..272W"><span>A Magnetohydrodynamic Modeling of the Interchange Cycle for Oblique Northward <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watanabe, Masakazu; Fujita, Shigeru; Tanaka, Takashi; Kubota, Yasubumi; Shinagawa, Hiroyuki; Murata, Ken T.</p> <p>2018-01-01</p> <p>We perform numerical modeling of the interchange cycle in the magnetosphere-ionosphere convection system for oblique northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF). The interchange cycle results from the coupling of IMF-to-lobe reconnection and lobe-to-closed reconnection. Using a global magnetohydrodynamic simulation code, for an IMF clock angle of 20° (measured from due north), we successfully reproduced the following features of the interchange cycle. (1) In the ionosphere, for each hemisphere, there appears a reverse cell circulating exclusively in the closed field line region (the reciprocal cell). (2) The topology transition of the <span class="hlt">magnetic</span> field along a streamline near the equatorial plane precisely represents the <span class="hlt">magnetic</span> flux reciprocation during the interchange cycle. (3) Field-aligned electric fields on the <span class="hlt">interplanetary</span>-open separatrix and on the open-closed separatrix are those that are consistent with IMF-to-lobe reconnection and lobe-to-closed reconnection, respectively. These three features prove the existence of the interchange cycle in the simulated magnetosphere-ionosphere system. We conclude that the interchange cycle does exist in the real solar wind-magnetosphere-ionosphere system. In addition, the simulation revealed that the reciprocal cell described above is not a direct projection of the diffusion region as predicted by the "vacuum" model in which diffusion is added a priori to the vacuum <span class="hlt">magnetic</span> topology. Instead, the reciprocal cell is a consequence of the plasma convection system coupled to the so-called NBZ ("northward <fi>B</fi><fi>z</fi>") field-aligned current system.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRA..117.6102V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRA..117.6102V"><span>Inferring <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field polarities from geomagnetic variations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vokhmyanin, M. V.; Ponyavin, D. I.</p> <p>2012-06-01</p> <p>In this paper, we propose a modified procedure to infer the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) polarities from geomagnetic observations. It allows to identify the polarity back to 1905. As previous techniques it is based on the well-known Svalgaard-Mansurov effect. We have improved the quality and accuracy of polarity inference compared with the previous results of Svalgaard (1975) and Vennerstroem et al. (2001) by adding new geomagnetic stations and extracting carefully diurnal curve. The data demonstrates an excess of one of the two IMF sectors within equinoxes (Rosenberg-Coleman rule) evidencing polar field reversals at least for the last eight solar cycles. We also found a predominance of the two-sector structure in late of descending phase of solar cycle 16.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017P%26SS..148...28G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017P%26SS..148...28G"><span>Shape of the equatorial magnetopause affected by the radial <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grygorov, K.; Šafránková, J.; Němeček, Z.; Pi, G.; Přech, L.; Urbář, J.</p> <p>2017-11-01</p> <p>The ability of a prediction of the magnetopause location under various upstream conditions can be considered as a test of our understanding of the solar wind-magnetosphere interaction. The present magnetopause models are parametrized with the solar wind dynamic pressure and usually with the north-south <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) component. However, several studies pointed out an importance of the radial IMF component, but results of these studies are controversial up to now. The present study compares magnetopause observations by five THEMIS spacecraft during long lasting intervals of the radial IMF with two empirical magnetopause models. A comparison reveals that the magnetopause location is highly variable and that the <span class="hlt">average</span> difference between the observed and predicted positions is ≈ + 0.7 RE under this condition. The difference does not depend on the local times and other parameters, like the upstream pressure, IMF north-south component, or tilt angle of the Earth dipole. We conclude that our results strongly support the suggestion on a global expansion of the equatorial magnetopause during intervals of the radial IMF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSH51C2135M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSH51C2135M"><span>Wavelet detection of coherent structures in <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> flux ropes and its role in the intermittent turbulence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muñoz, P. R.; Chian, A. C.</p> <p>2013-12-01</p> <p>We implement a method to detect coherent <span class="hlt">magnetic</span> structures using the Haar discrete wavelet transform (Salem et al., ApJ 702, 537, 2009), and apply it to an event detected by Cluster at the turbulent boundary layer of an <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> flux rope. The wavelet method is able to detect <span class="hlt">magnetic</span> coherent structures and extract main features of solar wind intermittent turbulence, such as the power spectral density and the scaling exponent of structure functions. Chian and Muñoz (ApJL 733, L34, 2011) investigated the relation between current sheets, turbulence, and <span class="hlt">magnetic</span> reconnections at the leading edge of an <span class="hlt">interplanetary</span> coronal mass ejection measured by Cluster upstream of the Earth's bow shock on 2005 January 21. We found observational evidence of two <span class="hlt">magnetically</span> reconnected current sheets in the vicinity of a front <span class="hlt">magnetic</span> cloud boundary layer, where the scaling exponent of structure functions of <span class="hlt">magnetic</span> fluctuations exhibits multifractal behavior. Using the wavelet technique, we show that the current sheets associated to <span class="hlt">magnetic</span> reconnection are part of the set of <span class="hlt">magnetic</span> coherent structures responsible for multifractality. By removing them using a filtering criteria, it is possible to recover a self-similar scaling exponent predicted for homogeneous turbulence. Finally, we discuss an extension of the wavelet technique to study coherent structures in two-dimensional solar magnetograms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AnGeo..26.3989S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AnGeo..26.3989S"><span>Forecasting intense geomagnetic activity using <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saiz, E.; Cid, C.; Cerrato, Y.</p> <p>2008-12-01</p> <p>Southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields are considered traces of geoeffectiveness since they are a main agent of <span class="hlt">magnetic</span> reconnection of solar wind and magnetosphere. The first part of this work revises the ability to forecast intense geomagnetic activity using different procedures available in the literature. The study shows that current methods do not succeed in making confident predictions. This fact led us to develop a new forecasting procedure, which provides trustworthy results in predicting large variations of Dst index over a sample of 10 years of observations and is based on the value Bz only. The proposed forecasting method appears as a worthy tool for space weather purposes because it is not affected by the lack of solar wind plasma data, which usually occurs during severe geomagnetic activity. Moreover, the results obtained guide us to provide a new interpretation of the physical mechanisms involved in the interaction between the solar wind and the magnetosphere using Faraday's law.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880053447&hterms=Magnetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DMagnetic%2Benergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880053447&hterms=Magnetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DMagnetic%2Benergy"><span>Transport equations for low-energy solar particles in evolving <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ng, C. K.</p> <p>1988-01-01</p> <p>Two new forms of a simplified Fokker-Planck equation are derived for the transport of low-energy solar energetic particles in an evolving <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, carried by a variable radial solar wind. An idealized solution suggests that the 'invariant' anisotropy direction reported by Allum et al. (1974) may be explained within the conventional theoretical framework. The equations may be used to relate studies of solar particle propagation to solar wind transients, and vice versa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22666106-average-spatial-distribution-cosmic-rays-behind-interplanetary-shockglobal-muon-detector-network-observations','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22666106-average-spatial-distribution-cosmic-rays-behind-interplanetary-shockglobal-muon-detector-network-observations"><span><span class="hlt">AVERAGE</span> SPATIAL DISTRIBUTION OF COSMIC RAYS BEHIND THE <span class="hlt">INTERPLANETARY</span> SHOCK—GLOBAL MUON DETECTOR NETWORK OBSERVATIONS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kozai, M.; Munakata, K.; Kato, C.</p> <p>2016-07-10</p> <p>We analyze the galactic cosmic ray (GCR) density and its spatial gradient in Forbush Decreases (FDs) observed with the Global Muon Detector Network (GMDN) and neutron monitors (NMs). By superposing the GCR density and density gradient observed in FDs following 45 <span class="hlt">interplanetary</span> shocks (IP-shocks), each associated with an identified eruption on the Sun, we infer the <span class="hlt">average</span> spatial distribution of GCRs behind IP-shocks. We find two distinct modulations of GCR density in FDs, one in the <span class="hlt">magnetic</span> sheath and the other in the coronal mass ejection (CME) behind the sheath. The density modulation in the sheath is dominant in themore » western flank of the shock, while the modulation in the CME ejecta stands out in the eastern flank. This east–west asymmetry is more prominent in GMDN data responding to ∼60 GV GCRs than in NM data responding to ∼10 GV GCRs, because of the softer rigidity spectrum of the modulation in the CME ejecta than in the sheath. The geocentric solar ecliptic- y component of the density gradient, G {sub y}, shows a negative (positive) enhancement in FDs caused by the eastern (western) eruptions, while G {sub z} shows a negative (positive) enhancement in FDs caused by the northern (southern) eruptions. This implies that the GCR density minimum is located behind the central flank of IP-shocks and propagating radially outward from the location of the solar eruption. We also confirmed that the <span class="hlt">average</span> G {sub z} changes its sign above and below the heliospheric current sheet, in accord with the prediction of the drift model for the large-scale GCR transport in the heliosphere.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940019861','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940019861"><span><span class="hlt">Magnetic</span> shielding of <span class="hlt">interplanetary</span> spacecraft against solar flare radiation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cocks, Franklin H.; Watkins, Seth</p> <p>1993-01-01</p> <p>The ultimate objective of this work is to design, build, and fly a dual-purpose, piggyback payload whose function is to produce a large volume, low intensity <span class="hlt">magnetic</span> field and to test the concept of using such a <span class="hlt">magnetic</span> field (1) to protect spacecraft against solar flare protons, (2) to produce a thrust of sufficient magnitude to stabilize low satellite orbits against orbital decay from atmospheric drag, and (3) to test the magsail concept. These all appear to be capable of being tested using the same deployed high temperature superconducting coil. In certain orbits, high temperature superconducting wire, which has now been developed to the point where silver-sheathed high T sub c wires one mm in diameter are commercially available, can be used to produce the <span class="hlt">magnetic</span> moments required for shielding without requiring any mechanical cooling system. The potential benefits of this concept apply directly to both earth-orbital and <span class="hlt">interplanetary</span> missions. The usefulness of a protective shield for manned missions needs scarcely to be emphasized. Similarly, the usefulness of increasing orbit perigee without expenditure of propellant is obvious. This payload would be a first step in assessing the true potential of large volume <span class="hlt">magnetic</span> fields in the US space program. The objective of this design research is to develop an innovative, prototype deployed high temperature superconducting coil (DHTSC) system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790012789','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790012789"><span>Contributions to the Fourth Solar Wind Conference. [<span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields and medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Acuna, M. H.; Behannon, K. W.; Burlaga, L. F.; Lepping, R.; Ness, N.; Ogilvie, K.; Pizzo, J.</p> <p>1979-01-01</p> <p>Recent results in <span class="hlt">interplanetary</span> physics are examined. These include observations of shock waves and post-shock <span class="hlt">magnetic</span> fields made by Voyager 1, 2; observations of the electron temperature as a function of distance between 1.36 AU and 2.25 AU; and observations of the structure of sector boundaries observed by Helios 1. A theory of electron energy transport in the collisionless solar wind is presented, and compared with observations. Alfven waves and Alvenic fluctuations in the solar wind are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22493833-transport-solar-electrons-turbulent-interplanetary-magnetic-field','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22493833-transport-solar-electrons-turbulent-interplanetary-magnetic-field"><span>Transport of solar electrons in the turbulent <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ablaßmayer, J.; Tautz, R. C., E-mail: robert.c.tautz@gmail.com; Dresing, N., E-mail: dresing@physik.uni-kiel.de</p> <p>2016-01-15</p> <p>The turbulent transport of solar energetic electrons in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field is investigated by means of a test-particle Monte-Carlo simulation. The <span class="hlt">magnetic</span> fields are modeled as a combination of the Parker field and a turbulent component. In combination with the direct calculation of diffusion coefficients via the mean-square displacements, this approach allows one to analyze the effect of the initial ballistic transport phase. In that sense, the model complements the main other approach in which a transport equation is solved. The major advancement is that, by recording the flux of particles arriving at virtual detectors, intensity and anisotropy-time profilesmore » can be obtained. Observational indications for a longitudinal asymmetry can thus be explained by tracing the diffusive spread of the particle distribution. The approach may be of future help for the systematic interpretation of observations for instance by the solar terrestrial relations observatory (STEREO) and advanced composition explorer (ACE) spacecrafts.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123.3238W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123.3238W"><span>Understanding the Twist Distribution Inside <span class="hlt">Magnetic</span> Flux Ropes by Anatomizing an <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wang, Yuming; Shen, Chenglong; Liu, Rui; Liu, Jiajia; Guo, Jingnan; Li, Xiaolei; Xu, Mengjiao; Hu, Qiang; Zhang, Tielong</p> <p>2018-05-01</p> <p><span class="hlt">Magnetic</span> flux rope (MFR) is the core structure of the greatest eruptions, that is, the coronal mass ejections (CMEs), on the Sun, and <span class="hlt">magnetic</span> clouds are posteruption MFRs in <span class="hlt">interplanetary</span> space. There is a strong debate about whether or not a MFR exists prior to a CME and how the MFR forms/grows through <span class="hlt">magnetic</span> reconnection during the eruption. Here we report a rare event, in which a <span class="hlt">magnetic</span> cloud was observed sequentially by four spacecraft near Mercury, Venus, Earth, and Mars, respectively. With the aids of a uniform-twist flux rope model and a newly developed method that can recover a shock-compressed structure, we find that the axial <span class="hlt">magnetic</span> flux and helicity of the <span class="hlt">magnetic</span> cloud decreased when it propagated outward but the twist increased. Our analysis suggests that the "pancaking" effect and "erosion" effect may jointly cause such variations. The significance of the pancaking effect is difficult to be estimated, but the signature of the erosion can be found as the imbalance of the azimuthal flux of the cloud. The latter implies that the <span class="hlt">magnetic</span> cloud was eroded significantly leaving its inner core exposed to the solar wind at far distance. The increase of the twist together with the presence of the erosion effect suggests that the posteruption MFR may have a high-twist core enveloped by a less-twisted outer shell. These results pose a great challenge to the current understanding on the solar eruptions as well as the formation and instability of MFRs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030056680','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030056680"><span>The <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field and Magnetospheric Current Systems</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>El-Alaoui, Mostafa</p> <p>2003-01-01</p> <p>We have performed systematic global magnetohydrodynamic (MHD) simulation studies driven by an idealized time series of solar wind parameters to establish basic cause and effect relationships between the solar wind variations and the ionosphere parameters. We studied six cases in which the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) rotated from southward to northward in one minute. In three cases (cases A, B, and C) we ran five hours of southward IMF with Beta(sub Zeta) = 5 nT, followed by five hours of northward IMF with Beta(sub Zeta) = 5 nT. In the other three cases (cases D, E, and F) the <span class="hlt">magnetic</span> field magnitude was increased to 10 nT. The solar wind parameters were: For cases A and D a density of 5 cm(exp -3), a thermal pressure of 3.3 nPa, and a solar wind speed 375 km/s, for cases B and E a density of 10 cm(exp -3), a thermal pressure of 9.9 nPa, and a solar wind speed 420 km/s, while for cases C and F a density of 15 cm(exp -3), a thermal pressure of 14.9 nPa, and a solar wind speed of 600 km/s.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015TESS....140503K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015TESS....140503K"><span>The <span class="hlt">magnetic</span> flux excess effect as a consequence of non-Parker radial evolution of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khabarova, Olga</p> <p>2015-04-01</p> <p>The “<span class="hlt">magnetic</span> flux excess” effect is exceeding of <span class="hlt">magnetic</span> flux Fs=4π|Br|r2 measured by distant spacecraft over the values obtained through measurements at the Earth’s orbit (Owens et al., JGR, 2008). Theoretically, its conservation should take place at any heliocentric distance r further than 10 solar radii, which means that the difference between the flux measured at 1 AU and Fs observed in another point in the heliosphere should be zero. However, the difference is negative closer to the Sun and increasingly positive at larger heliocentric distances. Possible explanations of this effect are continuously discussed, but the consensus is yet not reached.It is shown that a possible source of this effect is the solar wind expansion not accordingly with the Parker solution at least at low heliolatitudes. The difference between the experimentally found (r-5/3) and commonly used (r-2) radial dependence of the radial component of the IMF Br may lead to mistakes in the IMF point-to-point recalculations (Khabarova & Obridko, ApJ, 2012; Khabarova, Astronomy Reports, 2013). Using the observed Br (r) dependence, it is easy to find the variation of difference between the <span class="hlt">magnetic</span> flux Fs(r) at certain heliocentric distance r and Fs_1AU at 1 AU, which can be calculated as Fs(r)-Fs_1AU =4π·(B1AU /[1AU]-5/3) (r2-5/3 -[1AU]2-5/3) (Khabarova, Astronomy Reports, 2013).The possible influence of presence of the heliospheric current sheet near the ecliptic plane on the picture of <span class="hlt">magnetic</span> field lines and consequent deviation from the Parker's model is discussed.- Khabarova Olga, and Obridko Vladimir, Puzzles of the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field in the Inner Heliosphere, 2012, Astrophysical Journal, 761, 2, 82, doi:10.1088/0004-637X/761/2/82, http://arxiv.org/pdf/1204.6672v2.pdf- Olga V. Khabarova, The <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field: radial and latitudinal dependences. Astronomy Reports, 2013, Vol. 57, No. 11, pp. 844-859, http://arxiv.org/ftp/arxiv/papers/1305/1305.1204.pdf</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160014483&hterms=WEATHER&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DWEATHER','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160014483&hterms=WEATHER&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DWEATHER"><span><span class="hlt">Interplanetary</span> Space Weather Effects on Lunar Reconnaissance Orbiter Avalanche Photodiode Performance</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Clements, E. B.; Carlton, A. K.; Joyce, C. J.; Schwadron, N. A.; Spence, H. E.; Sun, X.; Cahoy, K.</p> <p>2016-01-01</p> <p>Space weather is a major concern for radiation-sensitive space systems, particularly for <span class="hlt">interplanetary</span> missions, which operate outside of the protection of Earth's <span class="hlt">magnetic</span> field. We examine and quantify the effects of space weather on silicon avalanche photodiodes (SiAPDs), which are used for <span class="hlt">interplanetary</span> laser altimeters and communications systems and can be sensitive to even low levels of radiation (less than 50 cGy). While ground-based radiation testing has been performed on avalanche photodiode (APDs) for space missions, in-space measurements of SiAPD response to <span class="hlt">interplanetary</span> space weather have not been previously reported. We compare noise data from the Lunar Reconnaissance Orbiter (LRO) Lunar Orbiter Laser Altimeter (LOLA) SiAPDs with radiation measurements from the onboard Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument. We did not find any evidence to support radiation as the cause of changes in detector threshold voltage during radiation storms, both for transient detector noise and long-term <span class="hlt">average</span> detector noise, suggesting that the approximately 1.3 cm thick shielding (a combination of titanium and beryllium) of the LOLA detectors is sufficient for SiAPDs on <span class="hlt">interplanetary</span> missions with radiation environments similar to what the LRO experienced (559 cGy of radiation over 4 years).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PPCF...56f4006M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PPCF...56f4006M"><span>Flux rope evolution in <span class="hlt">interplanetary</span> coronal mass ejections: the 13 May 2005 event</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Manchester, W. B., IV; van der Holst, B.; Lavraud, B.</p> <p>2014-06-01</p> <p>Coronal mass ejections (CMEs) are a dramatic manifestation of solar activity that release vast amounts of plasma into the heliosphere, and have many effects on the <span class="hlt">interplanetary</span> medium and on planetary atmospheres, and are the major driver of space weather. CMEs occur with the formation and expulsion of large-scale <span class="hlt">magnetic</span> flux ropes from the solar corona, which are routinely observed in <span class="hlt">interplanetary</span> space. Simulating and predicting the structure and dynamics of these <span class="hlt">interplanetary</span> CME <span class="hlt">magnetic</span> fields are essential to the progress of heliospheric science and space weather prediction. We discuss the simulation of the 13 May 2005 CME event in which we follow the propagation of a flux rope from the solar corona to beyond Earth orbit. In simulating this event, we find that the <span class="hlt">magnetic</span> flux rope reconnects with the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, to evolve to an open configuration and later reconnects to reform a twisted structure sunward of the original rope. Observations of the 13 May 2005 CME <span class="hlt">magnetic</span> field near Earth suggest that such a rearrangement of <span class="hlt">magnetic</span> flux by reconnection may have occurred.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760009906','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760009906"><span>Observations of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field between 0.46 and 1 A.U. by the Mariner 10 spacecraft. Ph.D. Thesis - Catholic Univ. of Am.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Behannon, K. W.</p> <p>1976-01-01</p> <p>Almost continuous measurement of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) at a sampling rate of 25 vectors/sec was performed by the <span class="hlt">magnetic</span> field experiment onboard the Mariner 10 spacecraft during the period November 3, 1973 to April 14, 1974, comprising approximately 5-2/3 solar rotations and extending in radial distance from the sun from 1 to 0.46 AU. A clearly discernible two-sector pattern of field polarity was observed during the last 3-1/2 months of the period, with the dominant polarity toward the sun below the solar equatorial plane. Two compound high-speed solar wind streams were also present during this period, one in each <span class="hlt">magnetic</span> field sector. Relative fluctuations of the field in magnitude and direction were found to have large time variations, but on <span class="hlt">average</span> the relative magnitude fluctuations were approximately constant over the range of heliocentric distance covered while the relative directional fluctuations showed a slight decrease on <span class="hlt">average</span> with increasing distance. The occurrence rate of directional discontinuities was also found to decrease with increasing radial distance from the sun.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...856...86M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...856...86M"><span>Evolution of <span class="hlt">Magnetic</span> Rayleigh–Taylor Instability into the Outer Solar Corona and Low <span class="hlt">Interplanetary</span> Space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mishra, Sudheer K.; Singh, Talwinder; Kayshap, P.; Srivastava, A. K.</p> <p>2018-03-01</p> <p>We analyze the observations from Solar TErrestrial RElations Observatory (STEREO)-A and B/COR-1 of an eruptive prominence in the intermediate corona on 2011 June 7 at 08:45 UT, which consists of <span class="hlt">magnetic</span> Rayleigh–Taylor (MRT) unstable plasma segments. Its upper-northward segment shows spatio-temporal evolution of MRT instability in form of finger structures up to the outer corona and low <span class="hlt">interplanetary</span> space. Using the method of Dolei et al., It is estimated that the density in each bright finger is greater than the corresponding dark region lying below it in the surrounding intermediate corona. The instability is evolved due to wave perturbations that are parallel to the <span class="hlt">magnetic</span> field at the density interface. We conjecture that the prominence plasma is supported by tension component of the <span class="hlt">magnetic</span> field against gravity. Through the use of linear stability theory, the <span class="hlt">magnetic</span> field is estimated as 21–40 mG to suppress growth of MRT instability in the observed finger structures. In the southward plasma segment, a horn-like structure is observed at 11:55 UT in the intermediate corona that also indicates MRT instability. Falling blobs are also observed in both of the plasma segments. In the outer corona, up to 6–13 solar radii, the mushroom-like plasma structures have been identified in the upper-northward MRT unstable plasma segment using STEREO-A/COR-2. These structures most likely grew due to the breaking and twisting of fingers at large spatial scales in weaker <span class="hlt">magnetic</span> fields. In the lower <span class="hlt">interplanetary</span> space up to 20 solar radii, these structures are fragmented into various small-scale localized plasma spikes, most likely due to turbulent mixing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970021679','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970021679"><span>Latitudinal Dependence of the Radial IMF Component - <span class="hlt">Interplanetary</span> Imprint</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Suess, S. T.; Smith, E. J.; Phillips, J.; Goldstein, B. E.; Nerney, S.</p> <p>1996-01-01</p> <p>Ulysses measurements have confirmed that there is no significant gradient with respect to heliomagnetic latitude in the radial component, B(sub r,), of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. There are two processes responsible for this observation. In the corona, the plasma beta is much less than 1, except directly above streamers, so both longitudinal and latitudinal (meridional) gradients in field strength will relax, due to the transverse <span class="hlt">magnetic</span> pressure gradient force, as the solar wind carries <span class="hlt">magnetic</span> flux away from the Sun. This happens so quickly that the field is essentially uniform by 5 solar radius. Beyond 10 solar radius, beta is greater than 1 and it is possible for a meridional thermal pressure gradient to redistribute <span class="hlt">magnetic</span> flux - an effect apparently absent in Ulysses and earlier ICE and <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Physics (IMP) data. We discuss this second effect here, showing that its absence is mainly due to the perpendicular part of the anisotropic thermal pressure gradient in the <span class="hlt">interplanetary</span> medium being too small to drive significant meridional transport between the Sun and approx. 4 AU. This is done using a linear analytic estimate of meridional transport. The first effect was discussed in an earlier paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSH51G..06J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSH51G..06J"><span>The Stereo Electron Spikes and the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jokipii, J. R.; Sheeley, N. R., Jr.; Wang, Y. M.; Giacalone, J.</p> <p>2016-12-01</p> <p>A recent paper (Klassen etal, 2015) discussed observations of a spike event of 55-65 keV electrons which occurred very nearly simultaneously at STEREO A and STEREO B, which at the time were separated in longitude by 38 degrees. The authors associated the spikes with a flare at the Sun near the footpoint of the nominal Archimedean spiral <span class="hlt">magnetic</span> field line passing through STEREO A. The spike at STEREO A was delayed by 2.2 minutes from that at STEREOB. We discuss the observations in terms of a model in which the electrons, accelerated at the flare, propagate without significant scattering along <span class="hlt">magnetic</span> field lines which separate or diverge as a function of radial distance from the Sun. The near simultaneity of the spikes at the two spacecraft is a natural consequence of this model. We interpret the divergence of the <span class="hlt">magnetic</span> field lines as a consequence of field-line random walk and flux-tube expansion. We show that the field-line random walk in the absence of flux-tube expansion produces an rms spread of field lines significantly less than that which is required to produce to observed divergence. We find that observations of the solar wind and its source region at the time of the event can account for the observations in terms of propagation along <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field-lines. Klassen, A., Dresing, N., Gomez-Herrero, R, and Heber, B., A&A 580, A115 (2015) Financial support for NS and YMW was provided by NASA and CNR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007JGRA..11211103X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007JGRA..11211103X"><span>Magnetohydrodynamic simulation of the interaction between two <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds and its consequent geoeffectiveness</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xiong, Ming; Zheng, Huinan; Wu, S. T.; Wang, Yuming; Wang, Shui</p> <p>2007-11-01</p> <p>Numerical studies of the <span class="hlt">interplanetary</span> "multiple <span class="hlt">magnetic</span> clouds (Multi-MC)" are performed by a 2.5-dimensional ideal magnetohydrodynamic (MHD) model in the heliospheric meridional plane. Both slow MC1 and fast MC2 are initially emerged along the heliospheric equator, one after another with different time intervals. The coupling of two MCs could be considered as the comprehensive interaction between two systems, each comprising of an MC body and its driven shock. The MC2-driven shock and MC2 body are successively involved into interaction with MC1 body. The momentum is transferred from MC2 to MC1. After the passage of MC2-driven shock front, <span class="hlt">magnetic</span> field lines in MC1 medium previously compressed by MC2-driven shock are prevented from being restored by the MC2 body pushing. MC1 body undergoes the most violent compression from the ambient solar wind ahead, continuous penetration of MC2-driven shock through MC1 body, and persistent pushing of MC2 body at MC1 tail boundary. As the evolution proceeds, the MC1 body suffers from larger and larger compression, and its original vulnerable <span class="hlt">magnetic</span> elasticity becomes stiffer and stiffer. So there exists a maximum compressibility of Multi-MC when the accumulated elasticity can balance the external compression. This cutoff limit of compressibility mainly decides the maximally available geoeffectiveness of Multi-MC because the geoeffectiveness enhancement of MCs interacting is ascribed to the compression. Particularly, the greatest geoeffectiveness is excited among all combinations of each MC helicity, if <span class="hlt">magnetic</span> field lines in the interacting region of Multi-MC are all southward. Multi-MC completes its final evolutionary stage when the MC2-driven shock is merged with MC1-driven shock into a stronger compound shock. With respect to Multi-MC geoeffectiveness, the evolution stage is a dominant factor, whereas the collision intensity is a subordinate one. The <span class="hlt">magnetic</span> elasticity, <span class="hlt">magnetic</span> helicity of each MC, and compression</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26SS....4..257A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26SS....4..257A"><span>Study of field-aligned current (FAC), <span class="hlt">interplanetary</span> electric field component (Ey), <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field component (Bz), and northward (x) and eastward (y) components of geomagnetic field during supersubstorm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Adhikari, Binod; Dahal, Subodh; Chapagain, Narayan P.</p> <p>2017-05-01</p> <p>A dominant process by which energy and momentum are transported from the magnetosphere to the ionosphere is known as field-aligned current (FAC). It is enhanced during <span class="hlt">magnetic</span> reconnection and explosive energy release at a substorm. In this paper, we studied FAC, <span class="hlt">interplanetary</span> electric field component (Ey), <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field component (Bz), and northward (x) and eastward (y) components of geomagnetic field during three events of supersubstorm occurred on 24 November 2001, 21 January 2005, and 24 August 2005. Large-scale FAC, supposed to be produced during supersubstorm (SSS), has potentiality to cause blackout on Earth. We examined temporal variations of the x and y components of high-latitude geomagnetic field during SSS, which is attributed to the FACs. We shall report the characteristics of high-latitude northward and eastward components of geomagnetic field variation during the growth phase of SSS by the implementation of discrete wavelet transform (DWT) and cross-correlation analysis. Among three examples of SSS events, the highest peak value of FAC was estimated to be 19 μAm-2. This is shore up with the prediction made by Parks (1991) and Stasiewicz et al. (1998) that the FACs may vary from a few tens to several hundred μAm-2. Although this peak value of FACs for SSS event is much higher than the <span class="hlt">average</span> FACs associated with regular substorms or <span class="hlt">magnetic</span> storms, it is expedient and can be expect for SSS events which might be due to very high density solar wind plasma parcels (PPs) triggering the SSS events. In all events, during growth phase, the FAC increases to extremely high level and the geomagnetic northward component decreases to extremely low level. This represents a strong positive correlation between FAC and geomagnetic northward component. The DWT analysis accounts that the highest amplitude of the wavelet coefficients indicates singularities present in FAC during SSS event. But the amplitude of squared wavelet coefficient is found</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870036903&hterms=quasi+particle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dquasi%2Bparticle','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870036903&hterms=quasi+particle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dquasi%2Bparticle"><span>Subcritical and supercritical <span class="hlt">interplanetary</span> shocks - <span class="hlt">Magnetic</span> field and energetic particle observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bavassano-Cattaneo, M. B.; Tsurutani, B. T.; Smith, E. J.; Lin, R. P.</p> <p>1986-01-01</p> <p>A study of 34 forward <span class="hlt">interplanetary</span> shocks observed by ISEE 3 during 1978 and 1979 has been conducted. <span class="hlt">Magnetic</span> field and high-energy particle data have been used, and for each shock the first critical Mach number has been determined. The first surprising result is that the majority of the observed shocks appear to be supercritical, and consistent with their supercritical character, many shocks have a foot and/or an overshoot in the <span class="hlt">magnetic</span> field structure. Large-amplitude low-frequency waves (period of about 20 s in the spacecraft frame) are commonly observed upstream of all supercritical shocks (except for a few quasi-perpendicular shocks) and also upstream of the few subcritical shocks. Intense particle events are frequently observed at many shocks: spikes at quasi-perpendicular shocks and energetic storm particle events associated with quasi-parallel shocks can be comparably intense. The correlation of the high-energy particle peak flux with various shock parameters is in agreement with the acceleration mechanisms proposed by previous studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770027147','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770027147"><span>Sources of <span class="hlt">magnetic</span> fields in recurrent <span class="hlt">interplanetary</span> streams</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burlaga, L. F.; Behannon, K. W.; Hansen, S. F.; Pneuman, G. W.; Feldman, W. C.</p> <p>1977-01-01</p> <p>The sources of <span class="hlt">magnetic</span> fields in recurrent streams were examined. Most fields and plasmas at 1 AU were related to coronal holes, and the <span class="hlt">magnetic</span> field lines were open in those holes. Some of the <span class="hlt">magnetic</span> fields and plasmas were related to open field line regions on the sun which were not associated with known coronal holes, indicating that open field lines are more basic than coronal holes as sources of the solar wind. <span class="hlt">Magnetic</span> field intensities in five equatorial coronal holes ranged from 2G to 18G. <span class="hlt">Average</span> measured photospheric <span class="hlt">magnetic</span> fields along the footprints of the corresponding unipolar fields on circular equatorial arcs at 2.5 solar radii had a similar range and <span class="hlt">average</span>, but in two cases the intensities were approximately three times higher than the projected intensities. The coronal footprints of the sector boundaries on the source surface at 2.5 solar radii, meandered between -45 deg and +45 deg latitude, and their inclination ranged from near zero to near ninety degrees.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110015529&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwhite%2Bcane','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110015529&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwhite%2Bcane"><span><span class="hlt">Interplanetary</span> Circumstances of Quasi-Perpendicular <span class="hlt">Interplanetary</span> Shocks in 1996-2005</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>2010-01-01</p> <p>The angle (theta(sub Bn)) between the normal to an <span class="hlt">interplanetary</span> shock front and the upstream <span class="hlt">magnetic</span> field direction, though often thought of as a property "of the shock," is also determined by the configuration of the <span class="hlt">magnetic</span> field immediately upstream of the shock. We investigate the <span class="hlt">interplanetary</span> circumstances of 105 near-Earth quasi-perpendicular shocks during 1996-2005 identified by theta(sub Bn) greater than or equal to 80 degrees and/or by evidence of shock drift particle acceleration. Around 87% of these shocks were driven by <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs); the remainder were probably the forward shocks of corotating interaction regions. For around half of the shocks, the upstream field was approximately perpendicular to the radial direction, either east-west or west-east or highly inclined to the ecliptic. Such field directions will give quasi-perpendicular configurations for radially propagating shocks. Around 30% of the shocks were propagating through, or closely followed, ICMEs at the time of observation. Another quarter were propagating through the heliospheric plasma sheet (HPS), and a further quarter occurred in slow solar wind that did not have characteristics of the HPS. Around 11% were observed in high-speed streams, and 7% in the sheaths following other shocks. The fraction of shocks found in high-speed streams is around a third of that expected based on the fraction of the time when such streams were observed at Earth. Quasi-perpendicular shocks are found traveling through ICMEs around 2-3 times more frequently than expected. In addition, shocks propagating through ICMEs are more likely to have larger values of theta(sub Bn) than shocks outside ICMEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720023138','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720023138"><span>Recurrent active regions related to metric radio continuum emissions and the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> sector structure</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sakurai, K.</p> <p>1972-01-01</p> <p>Active heliographic longitudes at the sun are investigated by using the observational data for long-lived metric continuum noise sources. It is shown that, for the period from 1963 to 1969, the number of such longitudes was four in general and these longitudes were very stable for this radio activity since 1963. A discussion is given on the relationship between those longitudes and the sector structure of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.9519L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.9519L"><span>Influence of <span class="hlt">interplanetary</span> solar wind sector polarity on the ionosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>liu, jing</p> <p>2014-05-01</p> <p>Knowledge of solar sector polarity effects on the ionosphere may provide some clues in understanding of the ionospheric day-to-day variability. A solar-terrestrial connection ranging from solar sector boundary (SB) crossings, geomagnetic disturbance and ionospheric perturbations has been demonstrated. The increases in <span class="hlt">interplanetary</span> solar wind speed within three days are seen after SB crossings, while the decreases in solar wind dynamic pressure and <span class="hlt">magnetic</span> field intensity immediately after SB crossings are confirmed by the superposed epoch analysis results. Furthermore, the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) Bz component turns from northward to southward in March equinox and June solstice as the Earth passes from a solar sector of outward to inward directed <span class="hlt">magnetic</span> fields, whereas the reverse situation occurs for the transition from toward to away sectors. The F2 region critical frequency (foF2) covering about four solar cycles and total electron content (TEC) during 1998-2011 are utilized to extract the related information, revealing that they are not modified significantly and vary within the range of 15% on <span class="hlt">average</span>. The responses of the ionospheric TEC to SB crossings exhibit complex temporal and spatial variations and have strong dependencies on season, latitude, and solar cycle. This effect is more appreciable in equinoctial months than in solstitial months, which is mainly caused by larger southward Bz components in equinox. In September equinox, latitudinal profile of relative variations of foF2 at noon is featured by depressions at high latitudes and enhancements in low-equatorial latitudes during IMF away sectors. The negative phase of foF2 is delayed at solar minimum relative to it during other parts of solar cycle, which might be associated with the difference in longevity of major <span class="hlt">interplanetary</span> solar wind drivers perturbing the Earth's environment in different phases of solar cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770005004','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770005004"><span>Radio observations of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field structures out of the ecliptic</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fitzenreiter, R. J.; Fainberg, J.; Weber, R. R.; Alvarez, H.; Haddock, F. T.; Potter, W. H.</p> <p>1976-01-01</p> <p>New observations of the out-of-the ecliptic trajectories of type 3 solar radio bursts have been obtained from simultaneous direction finding measurements on two independent satellite experiments, IMP-6 with spin plane in the ecliptic, and RAE-2 with spin plane normal to the ecliptic. Burst exciter trajectories were observed which originated at the active region and then crossed the ecliptic plane at about 0.8 AU. A considerable large scale north-south component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field is followed by the exciters. The apparent north-south and east-west angular source sizes observed by the two spacecraft are approximately equal, and range from 25 deg at 600 KHz to 110 deg at 80 KHz.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5477110-radio-scintillation-observations-interplanetary-disturbances','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5477110-radio-scintillation-observations-interplanetary-disturbances"><span>Radio-scintillation observations of <span class="hlt">interplanetary</span> disturbances</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Watanabe, T.; Kakinuma, T.</p> <p>1984-01-01</p> <p>Recent developments in the studies of <span class="hlt">interplanetary</span> disturbances by scintillation techniques are briefly reviewed. The turbulent postshock region of an <span class="hlt">interplanetary</span> disturbance produces transient enhancements in the scintillation level and the flow speed in many cases. An empirical method to determine three-dimensional angular distribution of the propagation speed of the disturbance on the basis of <span class="hlt">interplanetary</span> scintillation measurements of postshock flow speeds is applied to 17 events which took place in 1978-1981. Among them, four representative examples, including two events which were associated with disappearing solar filaments, are described in detail. Several disturbances had oblate configurations the latitudinal extent ismore » smaller than the longitudinal extent. On the <span class="hlt">average</span>, the angular distribution of the propagation speed at 1-AU heliocentric distance is quasi-isotropic over a longitudinal range of 100 deg centered at the normal of relevant solar phenomenon. The net excess mass and energy in an <span class="hlt">interplanetary</span> disturbance associated with a disappearing solar filament can be comparable to those of an <span class="hlt">interplanetary</span> disturbance associated with a large solar flare. 57 references.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018P%26SS..156....2L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018P%26SS..156....2L"><span>Nanodust released in <span class="hlt">interplanetary</span> collisions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lai, H. R.; Russell, C. T.</p> <p>2018-07-01</p> <p>The lifecycle of near-Earth objects (NEOs) involves a collisional cascade that produces ever smaller debris ending with nanoscale particles which are removed from the solar system by radiation pressure and electromagnetic effects. It has been proposed that the nanodust clouds released in collisions perturb the background <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and create the <span class="hlt">interplanetary</span> field enhancements (IFEs). Assuming that this IFE formation scenario is actually operating, we calculate the <span class="hlt">interplanetary</span> collision rate, estimate the total debris mass carried by nanodust, and compare the collision rate with the IFE rate. We find that to release the same amount of nanodust, the collision rate is comparable to the observed IFE rate. Besides quantitatively testing the association between the collisions evolving large objects and giant solar wind structures, such a study can be extended to ranges of smaller scales and to investigate the source of moderate and small solar wind perturbations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSA23B2398H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSA23B2398H"><span>Inter-Hemispheric Comparisons of the Ground <span class="hlt">Magnetic</span> Response to an <span class="hlt">Interplanetary</span> Shock</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hartinger, M.; Xu, Z.; Clauer, C. R.; Yu, Y.; Weimer, D. R.; Kim, H.; Pilipenko, V.; Welling, D. T.; Behlke, R.; Willer, A. N.</p> <p>2016-12-01</p> <p>Models predict that hemispheric differences in ionospheric conductivity affect the high-latitude ground <span class="hlt">magnetic</span> response during <span class="hlt">interplanetary</span> shock events. Using ground magnetometer observations from dense north-south chains in both the Northern (Greenland) and Southern (East Antarctic Plateau) hemispheres, we show an event study where that is not the case: nearly the same <span class="hlt">magnetic</span> response is observed in both hemispheres, despite near-solstice conditions when hemispheric conductivity differences should be large. We compare observations to virtual ground magnetometer output from global magnetohydrodynamic (MHD) simulations with the same driving conditions but different ionospheric conductivity profiles: (1) uniform conductivity, (2) variable conductivity appropriate for solar illumination during solstice, (3) the same as 2 but with additional conductivity contributions from auroral precipitation. There are major quantitative differences between simulations, with simulation 3 exhibiting the best agreement with data. Our results demonstrate the importance of constraining ionospheric conductivity - especially contributions from auroral precipitation - before interpreting hemispheric differences in ground <span class="hlt">magnetic</span> perturbation amplitude. We discuss the application of these results to techniques that relate high-latitude ground magnetometer observations to current or voltage generators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760036869&hterms=solar+geometry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bgeometry','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760036869&hterms=solar+geometry&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsolar%2Bgeometry"><span>A shock surface geometry - The February 15-16, 1967, event. [solar flare associated <span class="hlt">interplanetary</span> shock</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lepping, R. P.; Chao, J. K.</p> <p>1976-01-01</p> <p>An estimated shape is presented for the surface of the flare-associated <span class="hlt">interplanetary</span> shock of February 15-16, 1967, as seen in the ecliptic-plane cross section. The estimate is based on observations by Explorer 33 and Pioneers 6 and 7. The estimated shock normal at the Explorer 33 position is obtained by a least-squares shock parameter-fitting procedure for that satellite's data; the shock normal at the Pioneer 7 position is found by using the <span class="hlt">magnetic</span> coplanarity theorem and <span class="hlt">magnetic</span>-field data. The <span class="hlt">average</span> shock speed from the sun to each spacecraft is determined along with the local speed at Explorer 33 and the relations between these speeds and the position of the initiating solar flare. The Explorer 33 shock normal is found to be severely inclined and not typical of <span class="hlt">interplanetary</span> shocks. It is shown that the curvature of the shock surface in the ecliptic plane near the earth-Pioneer 7 region is consistent with a radius of not more than 0.4 AU.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080015820&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DOpen%2BField','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080015820&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DOpen%2BField"><span>An Alternative Interpretation of the Relationship between the Inferred Open Solar Flux and the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Riley, Pete</p> <p>2007-01-01</p> <p>Photospheric observations at the Wilcox Solar Observatory (WSO) represent an uninterrupted data set of 32 years and are therefore unique for modeling variations in the <span class="hlt">magnetic</span> structure of the corona and inner heliosphere over three solar cycles. For many years, modelers have applied a latitudinal correction factor to these data, believing that it provided a better estimate of the line-of-sight <span class="hlt">magnetic</span> field. Its application was defended by arguing that the computed open flux matched observations of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) significantly better than the original WSO correction factor. However, no physically based argument could be made for its use. In this Letter we explore the implications of using the constant correction factor on the value and variation of the computed open solar flux and its relationship to the measured IMF. We find that it does not match the measured IMF at 1 AU except at and surrounding solar minimum. However, we argue that <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) may provide sufficient additional <span class="hlt">magnetic</span> flux to the extent that a remarkably good match is found between the sum of the computed open flux and inferred ICME flux and the measured flux at 1 AU. If further substantiated, the implications of this interpretation may be significant, including a better understanding of the structure and strength of the coronal field and I N providing constraints for theories of field line transport in the corona, the modulation of galactic cosmic rays, and even possibly terrestrial climate effects.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021432&hterms=geofisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dgeofisica','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021432&hterms=geofisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dgeofisica"><span>The effects of 8 Helios observed solar proton events of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field fluctuations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>ValdezGalicia, J. F.; Alexander, P.; Otaola, J. A.</p> <p>1995-01-01</p> <p>There have been recent suggestions that large fluxes during solar energetic particle events may produce their own turbulence. To verify this argument it becomes essential to find out whether these flows cause an enhancement of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field fluctuations. In the present work, power and helicity spectra of the IMF before, during and after 8 Helios-observed solar proton events in the range 0.3 - 1 AU are analyzed. In order to detect proton self generated waves, the time evolution of spectra are followed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1987SoPh..114..407D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1987SoPh..114..407D"><span>Study of Travelling <span class="hlt">Interplanetary</span> Phenomena Report</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dryer, Murray</p> <p>1987-09-01</p> <p>Scientific progress on the topic of energy, mass, and momentum transport from the Sun into the heliosphere is contingent upon interdisciplinary and international cooperative efforts on the part of many workers. Summarized here is a report of some highlights of research carried out during the SMY/SMA by the STIP (Study of Travelling <span class="hlt">Interplanetary</span> Phenomena) Project that included solar and <span class="hlt">interplanetary</span> scientists around the world. These highlights are concerned with coronal mass ejections from solar flares or erupting prominences (sometimes together); their large-scale consequences in <span class="hlt">interplanetary</span> space (such as shocks and <span class="hlt">magnetic</span> 'bubbles'); and energetic particles and their relationship to these large-scale structures. It is concluded that future progress is contingent upon similar international programs assisted by real-time (or near-real-time) warnings of solar activity by cooperating agencies along the lines experienced during the SMY/SMA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860022023','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860022023"><span>Coronal and <span class="hlt">interplanetary</span> propagation, <span class="hlt">interplanetary</span> acceleration, cosmic-ray observations by deep space network and anomalous component</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ng, C. K.</p> <p>1986-01-01</p> <p>The purpose is to provide an overview of the contributions presented in sessions SH3, SH1.5, SH4.6 and SH4.7 of the 19th International Cosmic Ray Conference. These contributed papers indicate that steady progress continues to be made in both the observational and the theoretical aspects of the transport and acceleration of energetic charged particles in the heliosphere. Studies of solar and <span class="hlt">interplanetary</span> particles have placed emphasis on particle directional distributions in relation to pitch-angle scattering and <span class="hlt">magnetic</span> focusing, on the rigidity and spatial dependence of the mean free path, and on new propagation regimes in the inner and outer heliosphere. Coronal propagation appears in need of correlative multi-spacecraft studies in association with detailed observation of the flare process and coronal <span class="hlt">magnetic</span> structures. <span class="hlt">Interplanetary</span> acceleration has now gone into a consolidation phase, with theories being worked out in detail and checked against observation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018P%26SS..154....1B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018P%26SS..154....1B"><span>Geomagnetic response of <span class="hlt">interplanetary</span> coronal mass ejections in the Earth's magnetosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Badruddin; Mustajab, F.; Derouich, M.</p> <p>2018-05-01</p> <p>A coronal mass ejections (CME) is the huge mass of plasma with embedded <span class="hlt">magnetic</span> field ejected abruptly from the Sun. These CMEs propagate into <span class="hlt">interplanetary</span> space with different speed. Some of them hit the Earth's magnetosphere and create many types of disturbances; one of them is the disturbance in the geomagnetic field. Individual geomagnetic disturbances differ not only in their magnitudes, but the nature of disturbance is also different. It is, therefore, desirable to understand these differences not only to understand the physics of geomagnetic disturbances but also to understand the properties of solar/<span class="hlt">interplanetary</span> structures producing these disturbances of different magnitude and nature. In this work, we use the spacecraft measurements of CMEs with distinct <span class="hlt">magnetic</span> properties propagating in the <span class="hlt">interplanetary</span> space and generating disturbances of different levels and nature. We utilize their distinct plasma and field properties to search for the <span class="hlt">interplanetary</span> parameter(s) playing important role in influencing the geomagnetic response of different coronal mass ejections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...826...15F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...826...15F"><span>Observations of an <span class="hlt">Interplanetary</span> Intermediate Shock Associated with a <span class="hlt">Magnetic</span> Reconnection Exhaust</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, H. Q.; Li, Q. H.; Wang, J. M.; Zhao, G. Q.</p> <p>2016-07-01</p> <p>Two intermediate shocks (ISs) in <span class="hlt">interplanetary</span> space have been identified via one spacecraft observation. However, Feng et al. suggested that the analysis using a single spacecraft observation based only on the Rankine-Hugoniot (R-H) relations could misinterpret a tangential discontinuity (TD) as an IS. The misinterpretation can be fixed if two spacecraft observations are available. In this paper, we report an IS-like discontinuity associated with a <span class="hlt">magnetic</span> reconnection exhaust, which was observed by Wind on 2000 August 9 at 1 au. We investigated this discontinuity by fitting the R-H relations and referring to the Advanced Composition Explorer (ACE) observations. As a result, we found that the observed <span class="hlt">magnetic</span> field and plasma data satisfy the R-H relations well, and the discontinuity satisfies all the requirements of the 2\\to 3 type IS. Although the discontinuity cannot be identified strictly by using two spacecraft observations, in light of the ACE observations we consider that the discontinuity should be an IS rather than a TD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSM33A2155A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSM33A2155A"><span>Using ACE Observations of <span class="hlt">Interplanetary</span> Particles and <span class="hlt">Magnetic</span> Fields as Possible Contributors to Variations Observed at Van Allen Probes during Major events in 2013</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Armstrong, T. P.; Manweiler, J. W.; Gerrard, A. J.; Gkioulidou, M.; Lanzerotti, L. J.; Patterson, J. D.</p> <p>2013-12-01</p> <p>Observations from ACE EPAM including energy spectra of protons, helium, and oxygen will be prepared for coordinated use in estimating the direct and indirect access of energetic particles to inner and outer geomagnetic trapping zones. Complete temporal coverage from ACE at 12 seconds, 5 minutes, 17 minutes, hourly and daily cadences will be used to catalog <span class="hlt">interplanetary</span> events arriving at Earth including <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field sector boundaries, <span class="hlt">interplanetary</span> shocks, and <span class="hlt">interplanetary</span> coronal mass ejections, ICMEs. The first 6 months of 2013 have included both highly disturbed times, March 17 and May 22, and extended quiet periods of little or no variations. Among the specific questions that ACE and Van Allen Probes coordinated observations may aid in resolving are: 1. How much, if any, direct capture of <span class="hlt">interplanetary</span> energetic particles occurs and what conditions account for it? 2. How much influence do <span class="hlt">interplanetary</span> field and particle variations have on energization and/or loss of geomagnetically trapped populations? The poster will also present important links and describe methods and important details of access to numerically expressed ACE EPAM and Van Allen Probes RBSPICE observations that can be flexibly and easily accessed via the internet for student and senior researcher use.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AdSpR..55..401K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AdSpR..55..401K"><span>Variations of solar, <span class="hlt">interplanetary</span>, and geomagnetic parameters with solar <span class="hlt">magnetic</span> multipole fields during Solar Cycles 21-24</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Bogyeong; Lee, Jeongwoo; Yi, Yu; Oh, Suyeon</p> <p>2015-01-01</p> <p>In this study we compare the temporal variations of the solar, <span class="hlt">interplanetary</span>, and geomagnetic (SIG) parameters with that of open solar <span class="hlt">magnetic</span> flux from 1976 to 2012 (from Solar Cycle 21 to the early phase of Cycle 24) for a purpose of identifying their possible relationships. By the open flux, we mean the <span class="hlt">average</span> <span class="hlt">magnetic</span> field over the source surface (2.5 solar radii) times the source area as defined by the potential field source surface (PFSS) model of the Wilcox Solar Observatory (WSO). In our result, most SIG parameters except the solar wind dynamic pressure show rather poor correlations with the open solar <span class="hlt">magnetic</span> field. Good correlations are recovered when the contributions from individual multipole components are counted separately. As expected, solar activity indices such as sunspot number, total solar irradiance, 10.7 cm radio flux, and solar flare occurrence are highly correlated with the flux of <span class="hlt">magnetic</span> quadrupole component. The dynamic pressure of solar wind is strongly correlated with the dipole flux, which is in anti-phase with Solar Cycle (SC). The geomagnetic activity represented by the Ap index is correlated with higher order multipole components, which show relatively a slow time variation with SC. We also found that the unusually low geomagnetic activity during SC 23 is accompanied by the weak open solar fields compared with those in other SCs. It is argued that such dependences of the SIG parameters on the individual multipole components of the open solar <span class="hlt">magnetic</span> flux may clarify why some SIG parameters vary in phase with SC and others show seemingly delayed responses to SC variation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT.......128B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT.......128B"><span>Interaction of the geomagnetic field with northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bhattarai, Shree Krishna</p> <p></p> <p>The interaction of the solar wind with Earth's <span class="hlt">magnetic</span> field causes the transfer of momentum and energy from the solar wind to geospace. The study of this interaction is gaining significance as our society is becoming more and more space based, due to which, predicting space weather has become more important. The solar wind interacts with the geomagnetic field primarily via two processes: viscous interaction and the <span class="hlt">magnetic</span> reconnection. Both of these interactions result in the generation of an electric field in Earth's ionosphere. The overall topology and dynamics of the magnetosphere, as well as the electric field imposed on the ionosphere, vary with speed, density, and <span class="hlt">magnetic</span> field orientation of the solar wind as well as the conductivity of the ionosphere. In this dissertation, I will examine the role of northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) and discuss the global topology of the magnetosphere and the interaction with the ionosphere using results obtained from the Lyon-Fedder-Mobarry (LFM) simulation. The electric potentials imposed on the ionosphere due to viscous interaction and <span class="hlt">magnetic</span> reconnection are called the viscous and the reconnection potentials, respectively. A proxy to measure the overall effect of these potentials is to measure the cross polar potential (CPP). The CPP is defined as the difference between the maximum and the minimum of the potential in a given polar ionosphere. I will show results from the LFM simulation showing saturation of the CPP during periods with purely northward IMF of sufficiently large magnitude. I will further show that the viscous potential, which was assumed to be independent of IMF orientation until this work, is reduced during periods of northward IMF. Furthermore, I will also discuss the implications of these results for a simulation of an entire solar rotation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890058251&hterms=dependency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Ddependency','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890058251&hterms=dependency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Ddependency"><span>Some low-altitude cusp dependencies on the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Newell, Patrick T.; Meng, CHING-I.; Sibeck, David G.; Lepping, Ronald</p> <p>1989-01-01</p> <p>The low-altitude cusp dependencies on the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) were investigated using the algorithm of Newell and Meng (1988) to identify the cusp proper. The algorithm was applied to 12,569 high-latitude dayside passes of the DMSP F7 spacecraft, and the resulting cusp positioning data were correlated with the IMF. It was found that the cusp latitudinal position correlated reasonably well (0.70) with the Bz component when the IMF had a southward component. The correlation for the northward Bz component was only 0.18, suggestive of a half-wave rectifier effect. The ratio of cusp ion number flux precipitation for Bz southward to that for Bz northward was 1.75 + or - 0.12. The statistical local time widths of the cusp proper for the northward and the southward Bz components were found to be 2.1 h and 2.8 h, respectively.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140016484','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140016484"><span>The B-dot Earth <span class="hlt">Average</span> <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Capo-Lugo, Pedro A.; Rakoczy, John; Sanders, Devon</p> <p>2013-01-01</p> <p>The <span class="hlt">average</span> Earth's <span class="hlt">magnetic</span> field is solved with complex mathematical models based on mean square integral. Depending on the selection of the Earth <span class="hlt">magnetic</span> model, the <span class="hlt">average</span> Earth's <span class="hlt">magnetic</span> field can have different solutions. This paper presents a simple technique that takes advantage of the damping effects of the b-dot controller and is not dependent of the Earth <span class="hlt">magnetic</span> model; but it is dependent on the <span class="hlt">magnetic</span> torquers of the satellite which is not taken into consideration in the known mathematical models. Also the solution of this new technique can be implemented so easily that the flight software can be updated during flight, and the control system can have current gains for the <span class="hlt">magnetic</span> torquers. Finally, this technique is verified and validated using flight data from a satellite that it has been in orbit for three years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUSMSH23A..06G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUSMSH23A..06G"><span>About the Las Acacias, Trelew and Vassouras <span class="hlt">Magnetic</span> Observatories Monitoring the South Atlantic <span class="hlt">Magnetic</span> Anomaly Region Response to an <span class="hlt">Interplanetary</span> Coronal Mass Ejection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gianibelli, J. C.; Quaglino, N. M.</p> <p>2007-05-01</p> <p>The South Atlantic <span class="hlt">Magnetic</span> Anomaly (SAMA) Region presents evolutive characteristics very important as were observed by a variety of satelital sensors. Important <span class="hlt">Magnetic</span> Observatories with digital record monitor the effects of the Sun-Earth interaction, such as San Juan de Puerto Rico (SJG), Kourou (KOU), Vassouras (VSS), Las Acacias (LAS), Trelew (TRW), Vernadsky (AIA), Hermanus (HER) and Huancayo (HUA). In the present work we present the features registered during the geomagnetic storm in January 21, 2005, produced by a geoeffective Coronal Mass Ejection (CME) whose <span class="hlt">Interplanetary</span> Coronal Mass Ejection (ICME) was detected by the instrumental onboard the Advanced Composition Explorer (ACE) Sonde. We analize how the <span class="hlt">Magnetic</span> Total Intensity records at VSS, TRW and LAS Observatories shows the effect of the entering particles to ionospherical dephts producing a field enhancement following the first <span class="hlt">Interplanetary</span> Shock (IP) arrival of the ICME. This process manifest in the digital record as an increment over the magnetospheric Ring Current field effect and superinpossed effects over the Antarctic Auroral Electrojet. The analysis and comparison of the records demonstrate that the Ring Current effects are important in SJG and KOU but not in VSS, LAS and TRW observatories, concluding that SAMA region shows a enhancement of the ionospherical currents oposed to those generated at magnetospheric heighs. Moreover in TRW, 5 hours after the ICME shock arrival, shows the effect of the Antarctic Auroral Electrojet counteracting to fields generated by the Ring Current.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021314&hterms=rust&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Drust','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021314&hterms=rust&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Drust"><span><span class="hlt">Magnetic</span> clouds, helicity conservation, and intrinsic scale flux ropes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kumar, A.; Rust, D. M.</p> <p>1995-01-01</p> <p>An intrinsic-scale flux-rope model for <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds, incorporating conservation of <span class="hlt">magnetic</span> helicity, flux and mass is found to adequately explain clouds' <span class="hlt">average</span> thermodynamic and <span class="hlt">magnetic</span> properties. In spite their continuous expansion as they balloon into <span class="hlt">interplanetary</span> space, <span class="hlt">magnetic</span> clouds maintain high temperatures. This is shown to be due to <span class="hlt">magnetic</span> energy dissipation. The temperature of an expanding cloud is shown to pass through a maximum above its starting temperature if the initial plasma beta in the cloud is less than 2/3. Excess <span class="hlt">magnetic</span> pressure inside the cloud is not an important driver of the expansion as it is almost balanced by the tension in the helical field lines. It is conservation of <span class="hlt">magnetic</span> helicity and flux that requires that clouds expand radially as they move away from the Sun. Comparison with published data shows good agreement between measured cloud properties and theory. Parameters determined from theoretical fits to the data, when extended back to the Sun, are consistent with the origin of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds in solar filament eruptions. A possible extension of the heating mechanism discussed here to heating of the solar corona is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...851..123P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...851..123P"><span>A Sun-to-Earth Analysis of <span class="hlt">Magnetic</span> Helicity of the 2013 March 17–18 <span class="hlt">Interplanetary</span> Coronal Mass Ejection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pal, Sanchita; Gopalswamy, Nat; Nandy, Dibyendu; Akiyama, Sachiko; Yashiro, Seiji; Makela, Pertti; Xie, Hong</p> <p>2017-12-01</p> <p>We compare the <span class="hlt">magnetic</span> helicity in the 2013 March 17–18 <span class="hlt">interplanetary</span> coronal mass ejection (ICME) flux rope at 1 au and in its solar counterpart. The progenitor coronal mass ejection (CME) erupted on 2013 March 15 from NOAA active region 11692 and is associated with an M1.1 flare. We derive the source region reconnection flux using the post-eruption arcade (PEA) method that uses the photospheric magnetogram and the area under the PEA. The geometrical properties of the near-Sun flux rope is obtained by forward-modeling of white-light CME observations. Combining the geometrical properties and the reconnection flux, we extract the <span class="hlt">magnetic</span> properties of the CME flux rope. We derive the <span class="hlt">magnetic</span> helicity of the flux rope using its <span class="hlt">magnetic</span> and geometric properties obtained near the Sun and at 1 au. We use a constant-α force-free cylindrical flux rope model fit to the in situ observations in order to derive the <span class="hlt">magnetic</span> and geometric information of the 1 au ICME. We find a good correspondence in both amplitude and sign of the helicity between the ICME and the CME, assuming a semi-circular (half torus) ICME flux rope with a length of π au. We find that about 83% of the total flux rope helicity at 1 au is injected by the <span class="hlt">magnetic</span> reconnection in the low corona. We discuss the effect of assuming flux rope length in the derived value of the <span class="hlt">magnetic</span> helicity. This study connecting the helicity of <span class="hlt">magnetic</span> flux ropes through the Sun–Earth system has important implications for the origin of helicity in the <span class="hlt">interplanetary</span> medium and the topology of ICME flux ropes at 1 au and hence their space weather consequences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20020088125','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20020088125"><span>Long-term Trends in <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Strength and Solar Wind Structure during the 20th Century</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cliver, E. W.; Cane, H. V.; White, Nicholas E. (Technical Monitor)</p> <p>2002-01-01</p> <p>Lockwood et al have recently reported an approximately 40% increase in the radial component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) at Earth between 1964 and 1996. We argue that this increase does not constitute a secular trend but is largely the consequence of lower than <span class="hlt">average</span> fields during solar cycle 20 (1964-1976) in comparison with surrounding cycles. For times after 1976 the <span class="hlt">average</span> IMF strength has actually decreased slightly. Examination of the cosmic ray intensity, an indirect measure of the IMF strength, over the last five solar cycles (19-23) also indicates that cycle <span class="hlt">averages</span> of the IMF strength have been relatively constant since approximately 1954. We also consider the origin of the well-documented increase in the geomagnetic alphaalpha index that occurred primarily during the first half of the twentieth century. We surmise that the coronal mass ejection (CME) rate for recent solar cycles was approximately twice as high as that for solar cycles 100 years ago. However, this change in the CME rate and the accompanying increase in 27-day recurrent storm activity reported by others are unable to account completely for the increase in alphaalpha. Rather, the CMEs and recurrent high-speed streams at the beginning of the twentieth century must have been embedded in a background of slow solar wind that was less geoeffective (having, for example, lower IMF strength and/or flow speed) than its modern counterpart.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970026617','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970026617"><span>Penetration of the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field B(sub y) into Earth's Plasma Sheet</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hau, L.-N.; Erickson, G. M.</p> <p>1995-01-01</p> <p>There has been considerable recent interest in the relationship between the cross-tail <span class="hlt">magnetic</span> field component B(sub y) and tail dynamics. The purpose of this paper is to give an overall description of the penetration of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) B(sub y) into the near-Earth plasma sheet. We show that plasma sheet B(sub y) may be generated by the differential shear motion of field lines and enhanced by flux tube compression. The latter mechanism leads to a B(sub y) analogue of the pressure-balance inconsistency as flux tubes move from the far tail toward the Earth. The growth of B(sub y), however, may be limited by the dawn-dusk asymmetry in the shear velocity as a result of plasma sheet tilting. B(sub y) penetration into the plasma sheet implies field-aligned currents flowing between hemispheres. These currents together with the IMF B(sub y) related mantle field-aligned currents effectively shield the lobe from the IMF B(sub y).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870039705&hterms=vlahos&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dvlahos','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870039705&hterms=vlahos&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dvlahos"><span>Modeling of ion acceleration through drift and diffusion at <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Decker, R. B.; Vlahos, L.</p> <p>1986-01-01</p> <p>A test particle simulation designed to model ion acceleration through drift and diffusion at <span class="hlt">interplanetary</span> shocks is described. The technique consists of integrating along exact particle orbits in a system where the angle between the shock normal and mean upstream <span class="hlt">magnetic</span> field, the level of <span class="hlt">magnetic</span> fluctuations, and the energy of injected particles can assume a range of values. The technique makes it possible to study time-dependent shock acceleration under conditions not amenable to analytical techniques. To illustrate the capability of the numerical model, proton acceleration was considered under conditions appropriate for <span class="hlt">interplanetary</span> shocks at 1 AU, including large-amplitude transverse <span class="hlt">magnetic</span> fluctuations derived from power spectra of both ambient and shock-associated MHD waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730017140','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730017140"><span>Alfven wave refraction by <span class="hlt">interplanetary</span> inhomogeneities</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Daily, W. D.</p> <p>1973-01-01</p> <p>Pioneer 6 <span class="hlt">magnetic</span> data reveals that the propagation direction of Alfven waves in the <span class="hlt">interplanetary</span> medium is strongly oriented along the ambient field. <span class="hlt">Magnetic</span> fluctuations of frequencies up to 1/30 sec in the spacecraft frame are shown to satisfy a necessary condition for Alfven wave normal. It appears from this analysis that geometrical hydromagnetics may satisfactorily describe deviation of the wave normal from the background field. The rotational discontinuity is likely also to propagate along the field lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6931558-variations-ionospheric-plasma-concentration-region-main-ionospheric-trough-during-magnetic-storm-december-connection-measurements-interplanetary-magnetic-field','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6931558-variations-ionospheric-plasma-concentration-region-main-ionospheric-trough-during-magnetic-storm-december-connection-measurements-interplanetary-magnetic-field"><span>Variations of the ionospheric plasma concentration in the region of the main ionospheric trough during the <span class="hlt">magnetic</span> storm of December 18-19, 1978, in connection with measurements of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Gdalevich, G.L.; Afonin, V.V.; Eliseev, A.Y.</p> <p>1986-07-01</p> <p>Data from the Kosmos-900 satellite are used to examine variations of the ion concentration in the region of the main ionospheric trough at altitudes of about 500 km during the storm of December 18-19, 1978. These variations of ion densities are compared with the variations of the parameters of the <span class="hlt">interplanetary</span> medium, in particular, with the E /sub y/ = -VB /sub z/ component of the <span class="hlt">interplanetary</span> electric field. The results of the comparison are discussed. A scheme is proposed for the formation and motion of the trough during <span class="hlt">magnetic</span> disturbances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730051463&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D60%26Ntt%3Dlazarus','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730051463&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D60%26Ntt%3Dlazarus"><span>Observation and analysis of abrupt changes in the <span class="hlt">interplanetary</span> plasma velocity and <span class="hlt">magnetic</span> field.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Martin, R. N.; Belcher, J. W.; Lazarus, A. J.</p> <p>1973-01-01</p> <p>This paper presents a limited study of the physical nature of abrupt changes in the <span class="hlt">interplanetary</span> plasma velocity and <span class="hlt">magnetic</span> field based on 19 day's data from the Pioneer 6 spacecraft. The period was chosen to include a high-velocity solar wind stream and low-velocity wind. Abrupt events were accepted for study if the sum of the energy density in the <span class="hlt">magnetic</span> field and velocity changes was above a specified minimum. A statistical analysis of the events in the high-velocity solar wind stream shows that Alfvenic changes predominate. This conclusion is independent of whether steady state requirements are imposed on conditions before and after the event. Alfvenic changes do not dominate in the lower-speed wind. This study extends the plasma field evidence for outwardly propagating Alfvenic changes to time scales as small as 1 min (scale lengths on the order of 20,000 km).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720033802&hterms=Particles&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DZ%2BParticles','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720033802&hterms=Particles&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DZ%2BParticles"><span>Correlation of <span class="hlt">interplanetary</span>-space B sub z field fluctuations and trapped-particle redistribution.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Parks, G. K.; Pellat, R.</p> <p>1972-01-01</p> <p>Observations of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field fluctuations in correlation with trapped particle fluctuations are discussed. From observations of particle-redistribution effects, properties of the magnetospheric electric field are derived. The obtained results suggest that the <span class="hlt">interplanetary</span> B(sub z) field fluctuations might represent a strong driving source for particle diffusion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890058806&hterms=solar+two&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsolar%2Btwo','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890058806&hterms=solar+two&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsolar%2Btwo"><span><span class="hlt">Interplanetary</span> <span class="hlt">magnetic</span> field over two solar cycles and out to 20 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Smith, J. E.</p> <p>1989-01-01</p> <p><span class="hlt">Interplanetary</span> field measurements are now available from Pioneer and Voyager at large distances and from various spacecraft in the inner solar system. These multiple observations at different locations have proven indispensable in separating temporal from spatial dependences. The data set has revealed a number of characteristic solar cycle variations including changes in field strength and the inclination of the heliospheric current sheet responsible for <span class="hlt">magnetic</span> sectors. Spatial gradients in the field parameters out to 20 AU have been compared with the Parker Model including the spiral angle, the north-south field component and the magnitude. As a result of planetary encounters, Pioneer and the Voyagers are traveling outward at significantly different latitudes making it possible to investigate latitudinal, as well as radial, dependences. Effects associated with the pick-up of interstellar ions are being sought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760017031','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760017031"><span>Proceedings of the Symposium on the Study of the Sun and <span class="hlt">Interplanetary</span> Medium in Three Dimensions. [space mission planning and <span class="hlt">interplanetary</span> trajectories by NASA and ESA to better observe the sun and solar system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fisk, L. A. (Editor); Axford, W. I. (Editor)</p> <p>1976-01-01</p> <p>A series of papers are presented from a symposium attended by over 200 European and American scientists to examine the importance of exploring the <span class="hlt">interplanetary</span> medium and the sun by out-of-the-ecliptic space missions. The likely scientific returns of these missions in the areas of solar, <span class="hlt">interplanetary</span>, and cosmic ray physics is examined. Theoretical models of the solar wind and its interaction with <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields are given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SoPh..290..919T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SoPh..290..919T"><span><span class="hlt">Interplanetary</span> Propagation Behavior of the Fast Coronal Mass Ejection on 23 July 2012</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Temmer, M.; Nitta, N. V.</p> <p>2015-03-01</p> <p>The fast coronal mass ejection (CME) on 23 July 2012 caused attention because of its extremely short transit time from the Sun to 1 AU, which was shorter than 21 h. In situ data from STEREO-A revealed the arrival of a fast forward shock with a speed of more than 2200 km s-1 followed by a <span class="hlt">magnetic</span> structure moving with almost 1900 km s-1. We investigate the propagation behavior of the CME shock and <span class="hlt">magnetic</span> structure with the aim to reproduce the short transit time and high impact speed as derived from in situ data. We carefully measured the 3D kinematics of the CME using the graduated cylindrical shell model and obtained a maximum speed of 2580±280 km s-1 for the CME shock and 2270±420 km s-1 for its <span class="hlt">magnetic</span> structure. Based on the 3D kinematics, the drag-based model (DBM) reproduces the observational data reasonably well. To successfully simulate the CME shock, the ambient flow speed needs to have an <span class="hlt">average</span> value close to the slow solar wind speed (450 km s-1), and the initial shock speed at a distance of 30 R ⊙ should not exceed ≈ 2300 km s-1, otherwise it would arrive much too early at STEREO-A. The model results indicate that an extremely small aerodynamic drag force is exerted on the shock, smaller by one order of magnitude than <span class="hlt">average</span>. As a consequence, the CME hardly decelerates in <span class="hlt">interplanetary</span> space and maintains its high initial speed. The low aerodynamic drag can only be reproduced when the density of the ambient solar wind flow, in which the fast CME propagates, is decreased to ρ sw=1 - 2 cm-3 at the distance of 1 AU. This result is consistent with the preconditioning of <span class="hlt">interplanetary</span> space by a previous CME.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110023418&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwhite%2Bcane','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110023418&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwhite%2Bcane"><span>Galactic Cosmic Ray Intensity Response to <span class="hlt">Interplanetary</span> Coronal Mass Ejections/<span class="hlt">Magnetic</span> Clouds in 1995-2009</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>2011-01-01</p> <p>We summarize the response of the galactic cosmic ray (CGR) intensity to the passage of the more than 300 <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) and their associated shocks that passed the Earth during 1995-2009, a period that encompasses the whole of Solar Cycle 23. In approx.80% of cases, the GCR intensity decreased during the passage of these structures, i.e., a "Forbush decrease" occurred, while in approx.10% there was no significant change. In the remaining cases, the GCR intensity increased. Where there was an intensity decrease, minimum intensity was observed inside the ICME in approx.90% of these events. The observations confirm the role of both post-shock regions and ICMEs in the generation of these decreases, consistent with many previous studies, but contrary to the conclusion of Reames, Kahler, and Tylka (Astrophys. 1. Lett. 700, L199, 2009) who, from examining a subset of ICMEs with flux-rope-like <span class="hlt">magnetic</span> fields (<span class="hlt">magnetic</span> clouds) argued that these are "open structures" that allow free access of particles including GCRs to their interior. In fact, we find that <span class="hlt">magnetic</span> clouds are more likely to participate in the deepest GCR decreases than ICMEs that are not <span class="hlt">magnetic</span> clouds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050070873','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050070873"><span>The "Approximate 150 Day Quasi-Periodicity" in <span class="hlt">Interplanetary</span> and Solar Phenomena During Cycle 23</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>2004-01-01</p> <p>A"quasi-periodicity" of approx. 150 days in various solar and <span class="hlt">interplanetary</span> phenomena has been reported in earlier solar cycles. We suggest that variations in the occurrence of solar energetic particle events, <span class="hlt">inter-planetary</span> coronal mass ejections, and geomagnetic storm sudden commenceents during solar cycle 23 show evidence of this quasi-periodicity, which is also present in the sunspot number, in particular in the northern solar hemisphere. It is not, however, prominent in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field strength.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSA23A2533S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSA23A2533S"><span>Study of <span class="hlt">Magnetic</span> Field Spatial Variations in the Southern Hemisphere's Low Latitudes due to Different <span class="hlt">Interplanetary</span> Structures Using the 3-D MHD SWMF/BATSRUS Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Souza, V. M. C. E. S.; Jauer, P. R.; Alves, L. R.; Padilha, A. L.; Padua, M. B.; Vitorello, I.; Alves, M. V.; Da Silva, L. A.</p> <p>2017-12-01</p> <p><span class="hlt">Interplanetary</span> structures such as Coronal Mass Ejections (CME), Shocks, Corotating Interaction Regions (CIR) and <span class="hlt">Magnetic</span> Clouds (MC) interfere directly on Space Weather conditions and can cause severe and intense disturbances in the Earth's <span class="hlt">magnetic</span> field as measured in space and on the ground. During <span class="hlt">magnetically</span> disturbed periods characterized by world-wide, abrupt variations of the geomagnetic field, large and intense current systems can be induced and amplified within the Earth even at low latitudes. Such current systems are known as geomagnetically induced currents (GIC) and can cause damage to power transmission lines, transformers and the degradation of pipelines. As part of an effort to estimate GIC intensities throughout the low to equatorial latitudes of the Brazilian territory, we used the 3-D MHD SWMF/BATSRUS code to estimate spatial variations of the geomagnetic field during periods when the magnetosphere is under the influence of CME and MC structures. Specifically, we used the CalcDeltaB tool (Rastatter et al., Space Weather, 2014) to provide a proxy for the spatial variations of the geomagnetic field, with a 1 minute cadence, at 31 virtual magnetometer stations located in the proposed study region. The stations are spatially arranged in a two-dimensional network with each station being 5 degrees apart in latitude and longitude. In a preliminary analysis, we found that prior to the arrival of each <span class="hlt">interplanetary</span> structure, there is no appreciable variation in the components of the geomagnetic field between the virtual stations. However, when the <span class="hlt">interplanetary</span> structures reach the magnetosphere, each station perceives the <span class="hlt">magnetic</span> field variation differently, so that it is not possible to use a single station to represent the <span class="hlt">magnetic</span> field perturbation throughout the Brazilian region. We discuss the minimum number and spacing between stations to adequately detail the geomagnetic field variations in this region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011CosRe..49...21Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011CosRe..49...21Y"><span>Statistical study of <span class="hlt">interplanetary</span> condition effect on geomagnetic storms: 2. Variations of parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yermolaev, Yu. I.; Lodkina, I. G.; Nikolaeva, N. S.; Yermolaev, M. Yu.</p> <p>2011-02-01</p> <p>We investigate the behavior of mean values of the solar wind’s and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field’s (IMF) parameters and their absolute and relative variations during the <span class="hlt">magnetic</span> storms generated by various types of the solar wind. In this paper, which is a continuation of paper [1], we, on the basis of the OMNI data archive for the period of 1976-2000, have analyzed 798 geomagnetic storms with D st ≤ -50 nT and their <span class="hlt">interplanetary</span> sources: corotating interaction regions CIR, compression regions Sheath before the <span class="hlt">interplanetary</span> CMEs; <span class="hlt">magnetic</span> clouds MC; “Pistons” Ejecta, and an uncertain type of a source. For the analysis the double superposed epoch analysis method was used, in which the instants of the <span class="hlt">magnetic</span> storm onset and the minimum of the D st index were taken as reference times. It is shown that the set of <span class="hlt">interplanetary</span> sources of <span class="hlt">magnetic</span> storms can be sub-divided into two basic groups according to their slowly and fast varying characteristics: (1) ICME (MC and Ejecta) and (2) CIR and Sheath. The mean values, the absolute and relative variations in MC and Ejecta for all parameters appeared to be either mean or lower than the mean value (the mean values of the electric field E y and of the B z component of IMF are higher in absolute value), while in CIR and Sheath they are higher than the mean value. High values of the relative density variation sN/< N> are observed in MC. At the same time, the high values for relative variations of the velocity, B z component, and IMF magnitude are observed in Sheath and CIR. No noticeable distinctions in the relationships between considered parameters for moderate and strong <span class="hlt">magnetic</span> storms were observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19980227780','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19980227780"><span>Direct Measurements of <span class="hlt">Interplanetary</span> Dust Particles in the Vicinity of Earth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McCracken, C. W.; Alexander, W. M.; Dubin, M.</p> <p>1961-01-01</p> <p>The direct measurements made by the Explorer VIII satellite provide the first sound basis for analyzing all available direct measurements of the distribution of <span class="hlt">interplanetary</span> dust particles. The model <span class="hlt">average</span> distribution curve established by such an analysis departs significantly from that predicted by the (uncertain) extrapolation of results from meteor observations. A consequence of this difference is that the daily accretion of <span class="hlt">interplanetary</span> particulate matter by the earth is now considered to be mainly dust particles of the direct measurements range of particle size. Almost all the available direct measurements obtained with microphone systems on rockets, satellites, and spacecraft fit directly on the distribution curve defined by Explorer VIII data. The lack of reliable datum points departing significantly from the model <span class="hlt">average</span> distribution curve means that available direct measurements show no discernible evidence of an appreciable geocentric concentration of <span class="hlt">interplanetary</span> dust particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830059897&hterms=wave+oscillation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dwave%2Boscillation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830059897&hterms=wave+oscillation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dwave%2Boscillation"><span>Upstream electron oscillations and ion overshoot at an <span class="hlt">interplanetary</span> shock wave</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Potter, D. W.; Parks, G. K.</p> <p>1983-01-01</p> <p>During the passage of a large <span class="hlt">interplanetary</span> shock on Oct. 13, 1981, the ISEE-1 and -2 spacecraft were in the solar wind outside of the upstream region of the bow shock. The high time resolution data of the University of California particle instruments allow pinpointing the expected electron spike as occurring just before the <span class="hlt">magnetic</span> ramp. In addition, two features that occur at this shock have not been observed before: electron oscillations associated with low frequency waves upstream of the shock and sharp 'overshoot' (about 1 sec) in the ion fluxes that occur right after the <span class="hlt">magnetic</span> ramp. This <span class="hlt">interplanetary</span> shock exhibits many of the same characteristics that are observed at the earth's bow shock.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930055986&hterms=quasi+particle&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dquasi%2Bparticle','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930055986&hterms=quasi+particle&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dquasi%2Bparticle"><span>Quasi-linear theory and transport theory. [particle acceleration in <span class="hlt">interplanetary</span> medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Smith, Charles W.</p> <p>1992-01-01</p> <p>The theory of energetic particle scattering by magnetostatic fluctuations is reviewed in so far as it fails to produce the rigidity-independent mean-free-paths observed. Basic aspects of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field fluctuations are reviewed with emphasis placed on the existence of dissipation range spectra at high wavenumbers. These spectra are then incorporated into existing theories for resonant magnetostatic scattering and are shown to yield infinite mean-free-paths. Nonresonant scattering in the form of <span class="hlt">magnetic</span> mirroring is examined and offered as a partial solution to the magnetostatic problem. In the process, mean-free-paths are obtained in good agreement with observations in the <span class="hlt">interplanetary</span> medium at 1 AU and upstream of planetary bow shocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810058178&hterms=Electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DElectric%2Bcurrent','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810058178&hterms=Electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DElectric%2Bcurrent"><span>An electrodynamic model of electric currents and <span class="hlt">magnetic</span> fields in the dayside ionosphere of Venus</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cloutier, P. A.; Tascione, T. F.; Danieli, R. E., Jr.</p> <p>1981-01-01</p> <p>The electric current configuration induced in the ionosphere of Venus by the interaction of the solar wind has been calculated in previous papers (Cloutier and Daniell, 1973; Daniell and Cloutier, 1977; Cloutier and Daniell, 1979) for <span class="hlt">average</span> steady-state solar wind conditions and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. This model is generalized to include the effects of (1) plasma depletion and <span class="hlt">magnetic</span> field enhancement near the ionopause, (2) velocity-shear-induced MHD instabilities of the Kelvin-Helmholtz type within the ionosphere, and (3) variations in solar wind parameters and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. It is shown that the <span class="hlt">magnetic</span> field configuration resulting from the model varies in response to changes in solar wind and <span class="hlt">interplanetary</span> field conditions, and that these variations produce <span class="hlt">magnetic</span> field profiles in excellent agreement with those seen by the Pioneer-Venus Orbiter. The formation of flux-ropes by the Kelving-Helmholtz instability is shown to be a natural consequence of the model, with the spatial distribution and size of the flux-ropes determined by the <span class="hlt">magnetic</span> Reynolds number.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMSH13B1548H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMSH13B1548H"><span>The MHD simulation of <span class="hlt">interplanetary</span> space and heliosphere by using the boundary conditions of time-varying <span class="hlt">magnetic</span> field and IPS-based plasma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hayashi, K.; Tokumaru, M.; Kojima, M.; Fujiki, K.</p> <p>2008-12-01</p> <p>We present our new boundary treatment to introduce the temporal variation of the observation-based <span class="hlt">magnetic</span> field and plasma parameters on the inner boundary sphere (at 30 to 50 Rs) to the MHD simulation of the <span class="hlt">interplanetary</span> space and the simulation results. The boundary treatment to induce the time-variation of the <span class="hlt">magnetic</span> field including the radial component is essentially same as shown in our previous AGU meetings and newly modified so that the model can also include the variation of the plasma variables detected by IPS (<span class="hlt">interplanetary</span> scintillation) observation, a ground-based remote sensing technique for the solar wind plasma. We used the WSO (Wilcox Solar Observatory at Stanford University) for the solar <span class="hlt">magnetic</span> field input. By using the time-varying boundary condition, smooth variations of heliospheric MHD variables during the several Carrington solar rotation period are obtained. The simulation movie will show how the changes in the inner heliosphere observable by the ground-based instrument propagate outward and affects the outer heliosphere. The simulated MHD variables are compared with the Ulysses in-situ measurement data including ones made during its travel from the Earth to Jupiter for validation, and we obtain better agreements than with the simulation with fixed boundary conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850026542','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850026542"><span>The effect of the neutral sheet structure of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field on cosmic ray distribution in space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Alania, M. V.; Aslamazashvili, R. G.; Bochorishvili, T.; Djapiashvili, T. V.; Tkemaladze, V. S.</p> <p>1985-01-01</p> <p>Results of the numerical solution of the anistoropic diffusion equation are presented. The modulation depth of galactic cosmic rays is defined by the degree of curvature of the neutral current sheet in the heliosphere. The effect of the regular <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) on cosmic ray anisotropy in the period of solar activity minimum (in 1976) is analyzed by the data of the neutron super-monitors of the world network, and the heliolatitudinal gradient and cosmic ray diffusion coefficient are defined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850012177','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850012177"><span>Dependence of the High Latitude Middle Atmosphere Ionization on Structures in <span class="hlt">Interplanetary</span> Space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bremer, J.; Lauter, E. A.</p> <p>1984-01-01</p> <p>The precipitation of high energetic electrons during and after strong geomagnetic storms into heights below 100 km in middle and subauroral latitudes is markedly modulated by the structure of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF). Under relative quiet conditions the D-region ionization caused by high energetic particle precipitation (energies greater than 20 to 50 keV) depends on changes of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and also on the velocity of the solar wind. To test this assumption, the influence of the IMF-sector boundary crossings on ionospheric absorption data of high and middle latitudes by the superposed-epoch method was investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009632','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009632"><span>Search Coil vs. Fluxgate Magnetometer Measurements at <span class="hlt">Interplanetary</span> Shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, L.B., III</p> <p>2012-01-01</p> <p>We present <span class="hlt">magnetic</span> field observations at <span class="hlt">interplanetary</span> shocks comparing two different sample rates showing significantly different results. Fluxgate magnetometer measurements show relatively laminar supercritical shock transitions at roughly 11 samples/s. Search coil magnetometer measurements at 1875 samples/s, however, show large amplitude (dB/B as large as 2) fluctuations that are not resolved by the fluxgate magnetometer. We show that these fluctuations, identified as whistler mode waves, would produce a significant perturbation to the shock transition region changing the interpretation from laminar to turbulent. Thus, previous observations of supercritical <span class="hlt">interplanetary</span> shocks classified as laminar may have been under sampled.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040171393','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040171393"><span>The Fraction of <span class="hlt">Interplanetary</span> Coronal Mass Ejections That Are <span class="hlt">Magnetic</span> Clouds: Evidence for a Solar Cycle Variation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>2004-01-01</p> <p>"<span class="hlt">Magnetic</span> clouds" (MCs) are a subset of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) characterized by enhanced <span class="hlt">magnetic</span> fields with an organized rotation in direction, and low plasma beta. Though intensely studied, MCs only constitute a fraction of all the ICMEs that are detected in the solar wind. A comprehensive survey of ICMEs in the near- Earth solar wind during the ascending, maximum and early declining phases of solar cycle 23 in 1996 - 2003 shows that the MC fraction varies with the phase of the solar cycle, from approximately 100% (though with low statistics) at solar minimum to approximately 15% at solar maximum. A similar trend is evident in near-Earth observations during solar cycles 20 - 21, while Helios 1/2 spacecraft observations at 0.3 - 1.0 AU show a weaker trend and larger MC fraction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37.2056M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37.2056M"><span>Cosmic ray anisotropy along with <span class="hlt">interplanetary</span> transients</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mishra, Rajesh Kumar</p> <p></p> <p>The present work deals with the study of first three harmonics of low amplitude anisotropic wave trains of cosmic ray intensity over the period 1991-1994 for Deep River neutron monitoring station. It is observed that the diurnal time of maximum remains in the corotational direction; whereas, the time of maximum for both diurnal and semi-diurnal anisotropy has significantly shifted towards later hours as compared to the quiet day annual <span class="hlt">average</span> for majority of the LAE events. It is noticed that these events are not caused either by the high-speed solar wind streams or by the sources on the Sun responsible for producing these streams; such as, polar coronal holes. The direction of the tri-diurnal anisotropy shows a good negative correlation with Bz component of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. The occurrence of low amplitude events is dominant for positive polarity of Bz. The Disturbance Storm Time index i.e. Dst remains consistently negative only throughout the entire low amplitude wave train event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.6061O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.6061O"><span><span class="hlt">Interplanetary</span> density models as inferred from solar Type III bursts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oppeneiger, Lucas; Boudjada, Mohammed Y.; Lammer, Helmut; Lichtenegger, Herbert</p> <p>2016-04-01</p> <p>We report on the density models derived from spectral features of solar Type III bursts. They are generated by beams of electrons travelling outward from the Sun along open <span class="hlt">magnetic</span> field lines. Electrons generate Langmuir waves at the plasma frequency along their ray paths through the corona and the <span class="hlt">interplanetary</span> medium. A large frequency band is covered by the Type III bursts from several MHz down to few kHz. In this analysis, we consider the previous empirical density models proposed to describe the electron density in the <span class="hlt">interplanetary</span> medium. We show that those models are mainly based on the analysis of Type III bursts generated in the <span class="hlt">interplanetary</span> medium and observed by satellites (e.g. RAE, HELIOS, VOYAGER, ULYSSES,WIND). Those models are confronted to stereoscopic observations of Type III bursts recorded by WIND, ULYSSES and CASSINI spacecraft. We discuss the spatial evolution of the electron beam along the <span class="hlt">interplanetary</span> medium where the trajectory is an Archimedean spiral. We show that the electron beams and the source locations are depending on the choose of the empirical density models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.5192R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.5192R"><span>Dependence of the location of the Martian <span class="hlt">magnetic</span> lobes on the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field direction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Romanelli, Norberto; Mazelle, Christian; Bertucci, Cesar; Gomez, Daniel</p> <p>2016-04-01</p> <p>The <span class="hlt">magnetic</span> field topology surrounding the Martian atmosphere is mainly the result of gradients in the velocity of the solar wind (SW). Such variations in the SW velocity are in turn the result of a massloading process and forces associated with electric currents flowing around the ionosphere of Mars [Nagy et al 2004, Mazelle et al 2004, Brain et al 2015]. In particular, in the regions where the collisionless regime holds, the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) frozen into the SW piles up in front of the stagnation region of the flow. At the same time, the <span class="hlt">magnetic</span> field lines are stretched in the direction of the unperturbed SW as this stream moves away from Mars, giving rise to a magnetotail [Alfvén, 1957]. As a result and in contrast with an obstacle with and intrinsic global <span class="hlt">magnetic</span> field, the structure and organization of the <span class="hlt">magnetic</span> field around Mars depends on the direction of the IMF and its variabilities [Yeroshenko et al., 1990; Crider et al., 2004; Bertucci et al., 2003; Romanelli et al 2015]. In this study we use magnetometer data from the Mars Global Surveyor (MGS) spacecraft during portions of the premapping orbits of the mission to study the variability of the Martian-induced magnetotail as a function of the orientation of the IMF. The time spent by MGS in the magnetotail lobes during periods with positive solar wind flow-aligned IMF component B∥IMF suggests that their location as well as the position of the central polarity reversal layer (PRL) are displaced in the direction antiparallel to the IMF cross-flow component B⊥IMF . Analogously, in the cases where B∥IMF is negative, the lobes are displaced in the direction of B⊥IMF. We find this behavior to be compatible with a previously published B⊥IMF analytical model of the IMF draping, where for the first time, the displacement of a complementary reversal layer (denoted as IPRL for inverse polarity reversal layer) is deduced from first principles [Romanelli et al 2014]. We also</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ApJ...803...96S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ApJ...803...96S"><span>First Taste of Hot Channel in <span class="hlt">Interplanetary</span> Space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Song, H. Q.; Zhang, J.; Chen, Y.; Cheng, X.; Li, G.; Wang, Y. M.</p> <p>2015-04-01</p> <p>A hot channel (HC) is a high temperature (˜10 MK) structure in the inner corona first revealed by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. Eruptions of HCs are often associated with flares and coronal mass ejections (CMEs). Results of previous studies have suggested that an HC is a good proxy for a <span class="hlt">magnetic</span> flux rope (MFR) in the inner corona as well as another well known MFR candidate, the prominence-cavity structure, which has a normal coronal temperature (˜1-2 MK). In this paper, we report a high temperature structure (HTS, ˜1.5 MK) contained in an <span class="hlt">interplanetary</span> CME induced by an HC eruption. According to the observations of bidirectional electrons, high temperature and density, strong <span class="hlt">magnetic</span> field, and its association with the shock, sheath, and plasma pile-up region, we suggest that the HTS is the <span class="hlt">interplanetary</span> counterpart of the HC. The scale of the measured HTS is around 14 R ⊙ , and it maintained a much higher temperature than the background solar wind even at 1 AU. It is significantly different from the typical <span class="hlt">magnetic</span> clouds, which usually have a much lower temperature. Our study suggests that the existence of a corotating interaction region ahead of the HC formed a <span class="hlt">magnetic</span> container to inhibit expansion of the HC and cool it down to a low temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFMSH31A0232J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFMSH31A0232J"><span>GCR Modulation by Small-Scale Features in the <span class="hlt">Interplanetary</span> Medium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jordan, A. P.; Spence, H. E.; Blake, J. B.; Mulligan, T. L.; Shaul, D. N.; Galametz, M.</p> <p>2007-12-01</p> <p>In an effort to uncover the properties of structures in the <span class="hlt">interplanetary</span> medium (IPM) that modulate galactic cosmic rays (GCR) on short time-scales (from hours to days), we study periods of differing conditions in the IPM. We analyze GCR variations from spacecraft both inside and outside the magnetosphere, using the High Sensitivity Telescope (HIST) on Polar and the Spectrometer for INTEGRAL (SPI). We seek causal correlations between the observed GCR modulations and structures in the solar wind plasma and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, as measured concurrently with ACE and/or Wind. Our analysis spans time-/size-scale variations ranging from classic Forbush decreases (Fds), to substructure embedded within Fds, to much smaller amplitude and shorter duration variations observed during comparatively benign <span class="hlt">interplanetary</span> conditions. We compare and contrast the conditions leading to the range of different GCR responses to modulating structures in the IPM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120015887','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120015887"><span>Coronal Mass Ejections Near the Sun and in the <span class="hlt">Interplanetary</span> Medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, Nat</p> <p>2012-01-01</p> <p>Coronal mass ejections (CMEs) are the most energetic phenomenon in the heliosphere. During solar eruptions, the released energy flows out from the Sun in the form of <span class="hlt">magnetized</span> plasma and electromagnetic radiation. The electromagnetic radiation suddenly increases the ionization content of the ionosphere, thus impacting communication and navigation systems. The plasma clouds can drive shocks that accelerate charged particles to very high energies in the <span class="hlt">interplanetary</span> space, which pose radiation hazard to astronauts and space systems. The plasma clouds also arrive at Earth in about two days and impact Earth's magnetosphere, producing geomagnetic storms. The <span class="hlt">magnetic</span> storms result in a number of effects including induced currents that can disrupt power grids, railroads, and underground pipelines. This lecture presents an overview of the origin, propagation, and geospace consequences of CMEs and their <span class="hlt">interplanetary</span> counterparts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002758&hterms=Cyclotrons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26Nf%3DPublication-Date%257CBTWN%2B20150101%2B20180618%26N%3D0%26No%3D40%26Ntt%3DCyclotrons','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002758&hterms=Cyclotrons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26Nf%3DPublication-Date%257CBTWN%2B20150101%2B20180618%26N%3D0%26No%3D40%26Ntt%3DCyclotrons"><span>Outer Radiation Belt Dropout Dynamics Following the Arrival of Two <span class="hlt">Interplanetary</span> Coronal Mass Ejections</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Alves, L. R.; Da Silva, L. A.; Souza, V. M.; Sibeck, D. G.; Jauer, P. R.; Vieira, L. E. A.; Walsh, B. M.; Silveira, M. V. D.; Marchezi, J. P.; Rockenbach, M.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170002758'); toggleEditAbsImage('author_20170002758_show'); toggleEditAbsImage('author_20170002758_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170002758_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170002758_hide"></p> <p>2016-01-01</p> <p>Magnetopause shadowing and wave-particle interactions are recognized as the two primary mechanisms for losses of electrons from the outer radiation belt. We investigate these mechanisms, sing satellite observations both in <span class="hlt">interplanetary</span> space and within the magnetosphere and particle drift modeling. Two <span class="hlt">interplanetary</span> shocks sheaths impinged upon the magnetopause causing a relativistic electron flux dropout. The <span class="hlt">magnetic</span> cloud (C) and <span class="hlt">interplanetary</span> structure sunward of the MC had primarily northward <span class="hlt">magnetic</span> field, perhaps leading to a concomitant lack of substorm activity and a 10 day long quiescent period. The arrival of two shocks caused an unusual electron flux dropout. Test-particle simulations have shown 2 to 5 MeV energy, equatorially mirroring electrons with initial values of L 5.5can be lost to the magnetosheath via magnetopause shadowing alone. For electron losses at lower L-shells, coherent chorus wave-driven pitch angle scattering and ULF wave-driven radial transport have been shownto be viable mechanisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840005055','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840005055"><span>Plasma properties of driver gas following <span class="hlt">interplanetary</span> shocks observed by ISEE-3</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zwickl, R. D.; Asbridge, J. R.; Bame, S. J.; Feldman, W. C.; Gosling, J. T.; Smith, E. J.</p> <p>1983-01-01</p> <p>Plasma fluid parameters calculated from solar wind and <span class="hlt">magnetic</span> field data to determine the characteristic properties of driver gas following a select subset of <span class="hlt">interplanetary</span> shocks were studied. Of 54 shocks observed from August 1978 to February 1980, 9 contained a well defined driver gas that was clearly identifiable by a discontinuous decrease in the <span class="hlt">average</span> proton temperature. While helium enhancements were present downstream of the shock in all 9 of these events, only about half of them contained simultaneous changes in the two quantities. Simultaneous with the drop in proton temperature the helium and electron temperature decreased abruptly. In some cases the proton temperature depression was accompanied by a moderate increase in <span class="hlt">magnetic</span> field magnitude with an unusually low variance, by a small decrease in the variance of the bulk velocity, and by an increase in the ratio of parallel to perpendicular temperature. The cold driver gas usually displayed a bidirectional flow of suprathermal solar wind electrons at higher energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830025554','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830025554"><span>Plasma properties of driver gas following <span class="hlt">interplanetary</span> shocks observed by ISEE-3</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zwickl, R. D.; Ashbridge, J. R.; Bame, S. J.; Feldman, W. C.; Gosling, J. T.; Smith, E. J.</p> <p>1982-01-01</p> <p>Plasma fluid parameters calculated from solar wind and <span class="hlt">magnetic</span> field data obtained on ISEE 3 were studied. The characteristic properties of driver gas following <span class="hlt">interplanetary</span> shocks was determined. Of 54 shocks observed from August 1978 to February 1980, nine contained a well defined driver gas that was clearly identifiable by a discontinuous decrease in the <span class="hlt">average</span> proton temperature across a tangential discontinuity. While helium enhancements were present in all of nine of these events, only about half of them contained simultaneous changes in the two quantities. Often the He/H ratio changed over a period of minutes. Simultaneous with the drop in proton temperature the helium and electron temperature decreased abruptly. In some cases the proton temperature depression was accompanied by a moderate increase in <span class="hlt">magnetic</span> field magnitude with an unusually low variance and by an increase in the ratio of parallel to perpendicular temperature. The drive gas usually displayed a bidirectional flow of suprathermal solar wind electrons at higher energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMED11D0150S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMED11D0150S"><span>An Investigation of <span class="hlt">Interplanetary</span> Structures for Solar Cycles 23 and 24 and their Space Weather Consequences.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sultan, M. S.; Jules, A.; Marchese, P.; Damas, M. C.</p> <p>2017-12-01</p> <p>It is crucial to study space weather because severe <span class="hlt">interplanetary</span> conditions can cause geomagnetic storms that may damage both space- and ground-based technological systems such as satellites, communication systems, and power grids. <span class="hlt">Interplanetary</span> coronal mass ejections (ICMEs) and corotating interaction regions (CIRs) are the primary drivers of geomagnetic storms. As they travel through <span class="hlt">interplanetary</span> space and reach geospace, their spatial structures change which can result in various geomagnetic effects. Therefore, studying these drivers and their structures is essential in order to better understand and mitigate their impact on technological systems, as well as to forecast geomagnetic storms. In this study, over 150 storms were cross-checked for both solar cycles (SC) 23 and 24. This data has revealed the most common <span class="hlt">interplanetary</span> structures, i.e., sheath (Sh); <span class="hlt">magnetic</span> cloud following a shock front (sMC); sheath region and <span class="hlt">magnetic</span> cloud (Sh/MC); and corotating interaction regions (CIRs). Furthermore, plasma parameters as well as variation in the intensity and duration of storms resulting from different <span class="hlt">interplanetary</span> structures are studied for their effect on geomagnetically induced currents (GICs), as well as for their effect on power grids. Although preliminary results for SC 23 indicate that storm intensity may play a dominant role for GICs, duration might also be a factor, albeit smaller. Results from both SC 23 and 24 are analyzed and compared, and should lead to an enhanced understanding of space weather consequences of <span class="hlt">interplanetary</span> structures and their possible forecasting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19750043957&hterms=dependency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Ddependency','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19750043957&hterms=dependency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Ddependency"><span>The latitude dependencies of the solar wind. [of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field polarity and configurations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rosenberg, R. L.; Winge, C. R., Jr.</p> <p>1974-01-01</p> <p>The motion of spacecraft following the earth's orbit occurs within the solar latitude range of 7 deg 15 min N on approximately September 7 to 7 deg 15 min S on approximately March 6. The latitude dependencies so far detected within this range have shown that the photospheric dipole-like field of the sun makes very important contributions to the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) observed near the ecliptic. Changes in geomagnetic activity from even to odd numbered 11-year solar cycles are related to changes in the sun's dipolar field. The north-south IMF component and meridional, nonradial flow are important to a complete understanding of steady-state solar wind dynamics. Coronal conditions must be latitude-dependent in a way that accounts for the observed latitude dependence of the velocity and density of the solar wind.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870041528&hterms=Magnetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMagnetic%2Benergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870041528&hterms=Magnetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMagnetic%2Benergy"><span>Properties of a large-scale <span class="hlt">interplanetary</span> loop structure as deduced from low-energy proton anisotropy and <span class="hlt">magnetic</span> field measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tranquille, C.; Sanderson, T. R.; Marsden, R. G.; Wenzel, K.-P.; Smith, E. J.</p> <p>1987-01-01</p> <p>Correlated particle and <span class="hlt">magnetic</span> field measurements by the ISEE 3 spacecraft are presented for the loop structure behind the <span class="hlt">interplanetary</span> traveling shock event of Nov. 12, 1978. Following the passage of the turbulent shock region, strong bidirectional streaming of low-energy protons is observed for approximately 6 hours, corresponding to a loop thickness of about 0.07 AU. This region is also characterized by a low relative variance of the <span class="hlt">magnetic</span> field, a depressed proton intensity, and a reduction in the <span class="hlt">magnetic</span> power spectral density. Using quasi-linear theory applied to a slab model, a value of 3 AU is derived for the mean free path during the passage of the closed loop. It is inferred from this observation that the proton regime associated with the loop structure is experiencing scatter-free transport and that either the length of the loop is approximately 3 AU between the sun and the earth or else the protons are being reflected at both ends of a smaller loop.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22663951-preconditioning-interplanetary-space-due-transient-cme-disturbances','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22663951-preconditioning-interplanetary-space-due-transient-cme-disturbances"><span>Preconditioning of <span class="hlt">Interplanetary</span> Space Due to Transient CME Disturbances</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Temmer, M.; Reiss, M. A.; Hofmeister, S. J.</p> <p></p> <p><span class="hlt">Interplanetary</span> space is characteristically structured mainly by high-speed solar wind streams emanating from coronal holes and transient disturbances such as coronal mass ejections (CMEs). While high-speed solar wind streams pose a continuous outflow, CMEs abruptly disrupt the rather steady structure, causing large deviations from the quiet solar wind conditions. For the first time, we give a quantification of the duration of disturbed conditions (preconditioning) for <span class="hlt">interplanetary</span> space caused by CMEs. To this aim, we investigate the plasma speed component of the solar wind and the impact of in situ detected <span class="hlt">interplanetary</span> CMEs (ICMEs), compared to different background solar wind modelsmore » (ESWF, WSA, persistence model) for the time range 2011–2015. We quantify in terms of standard error measures the deviations between modeled background solar wind speed and observed solar wind speed. Using the mean absolute error, we obtain an <span class="hlt">average</span> deviation for quiet solar activity within a range of 75.1–83.1 km s{sup −1}. Compared to this baseline level, periods within the ICME interval showed an increase of 18%–32% above the expected background, and the period of two days after the ICME displayed an increase of 9%–24%. We obtain a total duration of enhanced deviations over about three and up to six days after the ICME start, which is much longer than the <span class="hlt">average</span> duration of an ICME disturbance itself (∼1.3 days), concluding that <span class="hlt">interplanetary</span> space needs ∼2–5 days to recover from the impact of ICMEs. The obtained results have strong implications for studying CME propagation behavior and also for space weather forecasting.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSM11B2304S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSM11B2304S"><span>Relativistic electron dropout echoes induced by <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schiller, Q.; Kanekal, S. G.; Boyd, A. J.; Baker, D. N.; Blake, J. B.; Spence, H. E.</p> <p>2017-12-01</p> <p><span class="hlt">Interplanetary</span> shocks that impact Earth's magnetosphere can produce immediate and dramatic responses in the trapped relativistic electron population. One well-studied response is a prompt injection capable of transporting relativistic electrons deep into the magnetosphere and accelerating them to multi-MeV energies. The converse effect, electron dropout echoes, are observations of a sudden dropout of electron fluxes observed after the <span class="hlt">interplanetary</span> shock arrival. Like the injection echo signatures, dropout echoes can also show clear energy dispersion signals. They are of particular interest because they have only recently been observed and their causal mechanism is not well understood. In the analysis presented here, we show observations of electron drift echo signatures from the Relativistic Electron-Proton Telescope (REPT) and <span class="hlt">Magnetic</span> Electron and Ion Sensors (MagEIS) onboard NASA's Van Allen Probes mission, which show simultaneous prompt enhancements and dropouts within minutes of the associated with shock impact. We show that the observations associated with both enhancements and dropouts are explained by the inward motion caused by the electric field impulse induced by the <span class="hlt">interplanetary</span> shock, and either energization to cause the enhancement, or lack of a seed population to cause the dropout.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880001352','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880001352"><span>Solar events and their influence on the <span class="hlt">interplanetary</span> medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Joselyn, Joann</p> <p>1987-01-01</p> <p>Aspects of a workshop on Solar events and their influence on the <span class="hlt">interplanetary</span> medium, held in September 1986, are reviewed, the goal of which was to foster interactions among colleagues, leading to an improved understanding of the unified relationship between solar events and <span class="hlt">interplanetary</span> disturbances. The workshop consisted of three working groups: (1) flares, eruptives, and other near-Sun activity; (2) coronal mass ejections; and (3) <span class="hlt">interplanetary</span> events. Each group discussed topics distributed in advance. The flares-eruptives group members agreed that pre-event energy is stored in stressed/sheared <span class="hlt">magnetic</span> fields, but could not agree that flares and other eruptive events (e.g., eruptive solar prominences) are aspects of the same physical phenomenon. In the coronal mass ejection group, general agreement was reached on the presence of prominences in CMEs, and that they have a significant three-dimensional structure. Some topics identified for further research were the aftermath of CMEs (streamer deflections, transient coronal holes, possible disconnections), identification of the leading edge of CMEs, and studies of the range and prevalence of CME mass sizes and energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Ap%26SS.363..106E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Ap%26SS.363..106E"><span>A study of the geomagnetic indices asymmetry based on the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field polarities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>El-Borie, M. A.; El-Taher, A. M.; Aly, N. E.; Bishara, A. A.</p> <p>2018-05-01</p> <p>Data of geomagnetic indices ( aa, Kp, Ap, and Dst) recorded near 1 AU over the period 1967-2016, have been studied based on the asymmetry between the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) directions above and below of the heliospheric current sheet (HCS). Our results led to the following conclusions: (i) Throughout the considered period, 31 random years (62%) showed apparent asymmetries between Toward (T) and Away (A) polarity days and 19 years (38%) exhibited nearly a symmetrical behavior. The days of A polarity predominated over the T polarity days by 4.3% during the positive <span class="hlt">magnetic</span> polarity epoch (1991-1999). While the days of T polarity exceeded the days of A polarity by 5.8% during the negative <span class="hlt">magnetic</span> polarity epoch (2001-2012). (ii) Considerable yearly North-South (N-S) asymmetries of geomagnetic indices observed throughout the considered period. (iii) The largest toward dominant peaks for aa and Ap indices occurred in 1995 near to minimum of solar activity. Moreover, the most substantial away dominant peaks for aa and Ap indices occurred in 2003 (during the descending phase of the solar cycle 23) and in 1991 (near the maximum of solar activity cycle) respectively. (iv) The N-S asymmetry of Kp index indicated a most significant away dominant peak occurred in 2003. (v) Four of the away dominant peaks of Dst index occurred at the maxima of solar activity in the years 1980, 1990, 2000, and 2013. The largest toward dominant peak occurred in 1991 (at the reversal of IMF polarity). (vi) The geomagnetic indices ( aa, Ap, and Kp) all have northern dominance during positive <span class="hlt">magnetic</span> polarity epoch (1971-1979), while the asymmetries shifts to the southern solar hemisphere during negative <span class="hlt">magnetic</span> polarity epoch (2001-2012).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850026690','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850026690"><span>The effect of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field on sidereal variations observed at medium depth underground detectors</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Humble, J. E.; Fenton, A. G.</p> <p>1985-01-01</p> <p>It has been known for some years that the intensity variations in sidereal time observed by muon detectors at moderate underground depths are sensitive to the polarity of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (ipmf) near the Earth. There are differences in the response to these anisotropies as observed in the Norhtern and southern hemispheres. When fully understood, the nature of the anisotropy seems likely to provide information on the 3-dimensional structure of the heliomagnetosphere, its time variations, and its linking with the local interstellar field. The summation harmonic dials for the sidereal diurnal variation during 1958 to 1982 show that there is a strong dependence on whether the ipmf near the Earth is directed outwards from the Sun or inwards it.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1326077-modeling-solar-wind-boundary-conditions-from-interplanetary-scintillations','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1326077-modeling-solar-wind-boundary-conditions-from-interplanetary-scintillations"><span>Modeling solar wind with boundary conditions from <span class="hlt">interplanetary</span> scintillations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Manoharan, P.; Kim, T.; Pogorelov, N. V.; ...</p> <p>2015-09-30</p> <p><span class="hlt">Interplanetary</span> scintillations make it possible to create three-dimensional, time- dependent distributions of the solar wind velocity. Combined with the <span class="hlt">magnetic</span> field observations in the solar photosphere, they help perform solar wind simulations in a genuinely time-dependent way. <span class="hlt">Interplanetary</span> scintillation measurements from the Ooty Radio Astronomical Observatory in India provide directions to multiple stars and may assure better resolution of transient processes in the solar wind. In this paper, we present velocity distributions derived from Ooty observations and compare them with those obtained with the Wang-Sheeley-Arge (WSA) model. We also present our simulations of the solar wind flow from 0.1 AUmore » to 1 AU with the boundary conditions based on both Ooty and WSA data.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1397256','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1397256"><span>Passive <span class="hlt">magnetic</span> bearing systems stabilizer/bearing utilizing time-<span class="hlt">averaging</span> of a periodic <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Post, Richard F.</p> <p></p> <p>A high-stiffness stabilizer/bearings for passive <span class="hlt">magnetic</span> bearing systems is provide where the key to its operation resides in the fact that when the frequency of variation of the repelling forces of the periodic <span class="hlt">magnet</span> array is large compared to the reciprocal of the growth time of the unstable motion, the rotating system will feel only the time-<span class="hlt">averaged</span> value of the force. When the time-<span class="hlt">averaged</span> value of the force is radially repelling by the choice of the geometry of the periodic <span class="hlt">magnet</span> array, the Earnshaw-related unstable hit motion that would occur at zero rotational speed is suppressed when the system ismore » rotating at operating speeds.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770062494&hterms=Exciter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DExciter','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770062494&hterms=Exciter&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DExciter"><span>Radio observations of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field structures out of the ecliptic. [related to type III solar bursts</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fitzenreiter, R. J.; Fainberg, J.; Weber, R. R.; Alvarez, H.; Haddock, F. T.; Potter, W. H.</p> <p>1977-01-01</p> <p>Observations of the out-of-ecliptic trajectories of type III solar radio bursts have been obtained from simultaneous direction-finding measurements in two independent satellite experiments, IMP-6 with spin plane in the ecliptic and RAE-2 with spin plane normal to the ecliptic. Burst-exciter trajectories were observed which originated at the active region and then crossed the ecliptic plane at about 0.8 AU. A considerable large-scale north-south component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field followed by the exciters is found. The apparent north-south and east-west angular source sizes observed by the two spacecraft are approximately equal, and range from 25 deg at 600 kHz to 110 deg at 80 kHz.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26167441','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26167441"><span>Saturn's dayside ultraviolet auroras: Evidence for morphological dependence on the direction of the upstream <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Meredith, C J; Alexeev, I I; Badman, S V; Belenkaya, E S; Cowley, S W H; Dougherty, M K; Kalegaev, V V; Lewis, G R; Nichols, J D</p> <p>2014-03-01</p> <p>We examine a unique data set from seven Hubble Space Telescope (HST) "visits" that imaged Saturn's northern dayside ultraviolet emissions exhibiting usual circumpolar "auroral oval" morphologies, during which Cassini measured the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) upstream of Saturn's bow shock over intervals of several hours. The auroras generally consist of a dawn arc extending toward noon centered near ∼15° colatitude, together with intermittent patchy forms at ∼10° colatitude and poleward thereof, located between noon and dusk. The dawn arc is a persistent feature, but exhibits variations in position, width, and intensity, which have no clear relationship with the concurrent IMF. However, the patchy postnoon auroras are found to relate to the (suitably lagged and <span class="hlt">averaged</span>) IMF B z , being present during all four visits with positive B z and absent during all three visits with negative B z . The most continuous such forms occur in the case of strongest positive B z . These results suggest that the postnoon forms are associated with reconnection and open flux production at Saturn's magnetopause, related to the similarly interpreted bifurcated auroral arc structures previously observed in this local time sector in Cassini Ultraviolet Imaging Spectrograph data, whose details remain unresolved in these HST images. One of the intervals with negative IMF B z however exhibits a prenoon patch of very high latitude emission extending poleward of the dawn arc to the <span class="hlt">magnetic</span>/spin pole, suggestive of the occurrence of lobe reconnection. Overall, these data provide evidence of significant IMF dependence in the morphology of Saturn's dayside auroras. We examine seven cases of joint HST Saturn auroral images and Cassini IMF dataThe persistent but variable dawn arc shows no obvious IMF dependencePatchy postnoon auroras are present for northward IMF but not for southward IMF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4497471','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4497471"><span>Saturn's dayside ultraviolet auroras: Evidence for morphological dependence on the direction of the upstream <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Meredith, C J; Alexeev, I I; Badman, S V; Belenkaya, E S; Cowley, S W H; Dougherty, M K; Kalegaev, V V; Lewis, G R; Nichols, J D</p> <p>2014-01-01</p> <p>We examine a unique data set from seven Hubble Space Telescope (HST) “visits” that imaged Saturn's northern dayside ultraviolet emissions exhibiting usual circumpolar “auroral oval” morphologies, during which Cassini measured the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) upstream of Saturn's bow shock over intervals of several hours. The auroras generally consist of a dawn arc extending toward noon centered near ∼15° colatitude, together with intermittent patchy forms at ∼10° colatitude and poleward thereof, located between noon and dusk. The dawn arc is a persistent feature, but exhibits variations in position, width, and intensity, which have no clear relationship with the concurrent IMF. However, the patchy postnoon auroras are found to relate to the (suitably lagged and <span class="hlt">averaged</span>) IMF Bz, being present during all four visits with positive Bz and absent during all three visits with negative Bz. The most continuous such forms occur in the case of strongest positive Bz. These results suggest that the postnoon forms are associated with reconnection and open flux production at Saturn's magnetopause, related to the similarly interpreted bifurcated auroral arc structures previously observed in this local time sector in Cassini Ultraviolet Imaging Spectrograph data, whose details remain unresolved in these HST images. One of the intervals with negative IMF Bz however exhibits a prenoon patch of very high latitude emission extending poleward of the dawn arc to the <span class="hlt">magnetic</span>/spin pole, suggestive of the occurrence of lobe reconnection. Overall, these data provide evidence of significant IMF dependence in the morphology of Saturn's dayside auroras. Key Points We examine seven cases of joint HST Saturn auroral images and Cassini IMF data The persistent but variable dawn arc shows no obvious IMF dependence Patchy postnoon auroras are present for northward IMF but not for southward IMF PMID:26167441</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSM33A2168L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSM33A2168L"><span>Adiabatic and nonadiabatic responses of the radiation belt relativistic electrons to the external changes in solar wind dynamic pressure and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, L.</p> <p>2013-12-01</p> <p>By removing the influences of 'magnetopause shadowing' (r0>6.6RE) and geomagnetic activities, we investigated statistically the responses of <span class="hlt">magnetic</span> field and relativistic (>0.5MeV) electrons at geosynchronous orbit to 201 <span class="hlt">interplanetary</span> perturbations during 6 years from 2003 (solar maximum) to 2008 (solar minimum). The statistical results indicate that during geomagnetically quiet times (HSYM ≥-30nT, and AE<200nT), ~47.3% changes in the geosynchronous <span class="hlt">magnetic</span> field and relativistic electron fluxes are caused by the combined actions of the enhancement of solar wind dynamic pressure (Pd) and the southward turning of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) (ΔPd>0.4 nPa, and IMF Bz<0 nT), and only ~18.4% changes are due to single dynamic pressure increase (ΔPd >0.4 nPa, but IMF Bz>0 nT), and ~34.3% changes are due to single southward turning of IMF (IMF Bz<0 nT, but |ΔPd|<0.4 nPa). Although the responses of <span class="hlt">magnetic</span> field and relativistic electrons to the southward turning of IMF are weaker than their responses to the dynamic pressure increase, the southward turning of IMF can cause the dawn-dusk asymmetric perturbations that the <span class="hlt">magnetic</span> field and the relativistic electrons tend to increase on the dawnside (LT~00:00-12:00) but decrease on the duskside (LT~13:00-23:00). Furthermore, the variation of relativistic electron fluxes is adiabatically controlled by the magnitude and elevation angle changes of <span class="hlt">magnetic</span> field during the single IMF southward turnings. However, the variation of relativistic electron fluxes is independent of the change in <span class="hlt">magnetic</span> field in some compression regions during the enhancement of solar wind dynamic pressure (including the single pressure increases and the combined external perturbations), indicating that nonadiabatic dynamic processes of relativistic electrons occur there. Acknowledgments. This work is supported by NSFC (grants 41074119 and 40604018). Liuyuan Li is grateful to the staffs working for the data from GOES 8-12 satellites</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910042730&hterms=magnetic+shield&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmagnetic%2Bshield','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910042730&hterms=magnetic+shield&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmagnetic%2Bshield"><span>A deployable high temperature superconducting coil (DHTSC) - A novel concept for producing <span class="hlt">magnetic</span> shields against both solar flare and Galactic radiation during manned <span class="hlt">interplanetary</span> missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cocks, F. Hadley</p> <p>1991-01-01</p> <p>The discovery of materials which are superconducting above 100 K makes possible the use of superconducting coils deployed beyong the hull of an <span class="hlt">interplanetary</span> spacecraft to produce a <span class="hlt">magnetic</span> shield capable of giving protection not only against solar flare radiation, but also even against Galactic radiation. Such deployed coils can be of very large size and can thus achieve the great <span class="hlt">magnetic</span> moments required using only relatively low currents. Deployable high-temperature-superconducting coil <span class="hlt">magnetic</span> shields appear to offer very substantial reductions in mass and energy compared to other concepts and could readily provide the radiation protection needed for a Mars mission or space colonies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810819B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810819B"><span>Multipoint study of <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blanco-Cano, Xochitl; Kajdic, Primoz; Russell, Christopher T.; Aguilar-Rodriguez, Ernesto; Jian, Lan K.; Luhmann, Janet G.</p> <p>2016-04-01</p> <p><span class="hlt">Interplanetary</span> (IP) shocks are driven in the heliosphere by <span class="hlt">Interplanetary</span> Coronal Mass Ejections (ICMEs) and Stream Interaction Regions (SIRs). These shocks perturb the solar wind plasma, and play an active role in the acceleration of ions to suprathermal energies. Shock fronts evolve as they move from the Sun. Their surfaces can be far from uniform and be modulated by changes in the ambient solar wind (<span class="hlt">magnetic</span> field orientation, flow velocity), shocks rippling, and perturbations upstream and downstream from the shocks, i.e., electromagnetic waves. In this work we use multipoint observations from STEREO, WIND, and MESSENGER missions to study shock characteristics at different helio-longitudes and determine the properties of the waves near them. We also determine shock longitudinal extensions and foreshock sizes. The variations of geometry along the shock surface can result in different extensions of the wave and ion foreshocks ahead of the shocks, and in different wave modes upstream and downtream of the shocks. We find that the ion foreshock can extend up to 0.2 AU ahead of the shock, and that the upstream region with modified solar wind/waves can be very asymmetric.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110005580','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110005580"><span>Atypical Particle Heating at a Supercritical <span class="hlt">Interplanetary</span> Shock</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, Lynn B., III</p> <p>2010-01-01</p> <p>We present the first observations at an <span class="hlt">interplanetary</span> shock of large amplitude (> 100 mV/m pk-pk) solitary waves and large amplitude (approx.30 mV/m pk-pk) waves exhibiting characteristics consistent with electron Bernstein waves. The Bernstein-like waves show enhanced power at integer and half-integer harmonics of the cyclotron frequency with a broadened power spectrum at higher frequencies, consistent with the electron cyclotron drift instability. The Bernstein-like waves are obliquely polarized with respect to the <span class="hlt">magnetic</span> field but parallel to the shock normal direction. Strong particle heating is observed in both the electrons and ions. The observed heating and waveforms are likely due to instabilities driven by the free energy provided by reflected ions at this supercritical <span class="hlt">interplanetary</span> shock. These results offer new insights into collisionless shock dissipation and wave-particle interactions in the solar wind.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.8709Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.8709Y"><span>Dependence of efficiency of <span class="hlt">magnetic</span> storm generation on the types of <span class="hlt">interplanetary</span> drivers.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yermolaev, Yuri; Nikolaeva, Nadezhda; Lodkina, Irina</p> <p>2015-04-01</p> <p>To compare the coupling coefficients between the solar-wind electric field Ey and Dst (and corrected Dst*) index during the <span class="hlt">magnetic</span> storms generated by different types of <span class="hlt">interplanetary</span> drivers, we use the Kyoto Dst-index data, the OMNI data of solar wind plasma and <span class="hlt">magnetic</span> field measurements, and our "Catalog of large scale phenomena during 1976-2000" (published in [1] and presented on websites: ftp://ftp.iki.rssi.ru/pub/omni/). Both indexes at the main phase of <span class="hlt">magnetic</span> storms are approximated by the linear dependence on the following solar wind parameters: integrated electric field of solar wind (sumEy), solar wind dynamic pressure (Pd), and the level of <span class="hlt">magnetic</span> field fluctuations (sB), and the fitting coefficients are determined by the technique of least squares. We present the results of the main phase modelling for <span class="hlt">magnetic</span> storms with Dst<-50 nT induced by 4 types of the solar wind streams: MC (10 events), CIR (41), Sheath (26), Ejecta (45). Our analysis [2, 3] shows that the coefficients of coupling between Dst and Dst* indexes and integral electric field are significantly higher for Sheath (for Dst*and Dst they are -3.4 and -3.3 nT/V m-1 h, respectively) and CIR (-3.0 and -2.8) than for MC (-2.0 and -2.5) and Ejecta (-2.1 and -2.3). Thus we obtained additional confirmation of experimental fact that Sheath and CIR have higher efficiency in generation of <span class="hlt">magnetic</span> storms than MC and Ejecta. This work was supported by the RFBR, project 13-02-00158a, and by the Program 9 of Presidium of Russian Academy of Sciences. References 1. Yu. I. Yermolaev, N. S. Nikolaeva, I. G. Lodkina, and M. Yu. Yermolaev, Catalog of Large-Scale Solar Wind Phenomena during 1976-2000, Cosmic Research, 2009, Vol. 47, No. 2, pp. 81-94. 2. N.S. Nikolaeva, Yu.I. Yermolaev, I.G. Lodkina, Modeling of Dst-index temporal profile on the main phase of the <span class="hlt">magnetic</span> storms generated by different types of solar wind, Cosmic Research, 2013, Vol. 51, No. 6, pp. 401-412 3. Nikolaeva N.S., Yermolaev</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ApJ...828L...7F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ApJ...828L...7F"><span>Separating Nightside <span class="hlt">Interplanetary</span> and Ionospheric Scintillation with LOFAR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fallows, R. A.; Bisi, M. M.; Forte, B.; Ulich, Th.; Konovalenko, A. A.; Mann, G.; Vocks, C.</p> <p>2016-09-01</p> <p>Observation of <span class="hlt">interplanetary</span> scintillation (IPS) beyond Earth-orbit can be challenging due to the necessity to use low radio frequencies at which scintillation due to the ionosphere could confuse the <span class="hlt">interplanetary</span> contribution. A recent paper by Kaplan et al. presenting observations using the Murchison Widefield Array (MWA) reports evidence of nightside IPS on two radio sources within their field of view. However, the low time cadence of 2 s used might be expected to <span class="hlt">average</span> out the IPS signal, resulting in the reasonable assumption that the scintillation is more likely to be ionospheric in origin. To check this assumption, this Letter uses observations of IPS taken at a high time cadence using the Low Frequency Array (LOFAR). <span class="hlt">Averaging</span> these to the same as the MWA observations, we demonstrate that the MWA result is consistent with IPS, although some contribution from the ionosphere cannot be ruled out. These LOFAR observations represent the first of nightside IPS using LOFAR, with solar wind speeds consistent with a slow solar wind stream in one observation and a coronal mass ejection expected to be observed in another.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950048767&hterms=1575&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2526%25231575','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950048767&hterms=1575&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2526%25231575"><span>The determination of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field polarities around sector boundaries using E greater than 2 keV electrons</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kahler, S.; Lin, R. P.</p> <p>1994-01-01</p> <p>The determination of the polarities of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields (whether the field direction is outward from or inward toward the sun) has been based on a comparison of observed field directions with the nominal Parker spiral angle. These polarities can be mapped back to the solar source field polarities. This technique fails when field directions deviate substantially from the Parker angle or when fields are substantially kinked. We introduce a simple new technique to determine the polarities of <span class="hlt">interplanetary</span> fields using E greater than 2 keV <span class="hlt">interplanetary</span> electrons which stream along field lines away from the sun. Those electrons usually show distinct unidirectional pitch-angle anisotropies either parallel or anti-parallel to the field. Since the electron flow direction is known to be outward from the sun, the anisotropies parallel to the field indicate outward-pointing, positive-polarity fields, and those anti-parallel indicate inward-pointing, negative-polarity fields. We use data from the UC Berkeley electron experiment on the International Sun Earth Explorer 3 (ISSE-3) spacecraft to compare the field polarities deduced from the electron data, Pe (outward or inward), with the polarities inferred from field directions, Pd, around two sector boundaries in 1979. We show examples of large (greater than 100 deg) changes in azimuthal field direction Phi over short (less than 1 hr) time scales, some with and some without reversals in Pe. The latter cases indicate that such large directional changes can occur in unipolar structures. On the other hand, we found an example of a change in Pe during which the rotation in Phi was less than 30 deg, indicating polarity changes in nearly unidirectional structures. The field directions are poor guides to the polarities in these cases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JGRA..11310102Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JGRA..11310102Q"><span>Local and nonlocal geometry of <span class="hlt">interplanetary</span> coronal mass ejections: Galactic cosmic ray (GCR) short-period variations and <span class="hlt">magnetic</span> field modeling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quenby, J. J.; Mulligan, T.; Blake, J. B.; Mazur, J. E.; Shaul, D.</p> <p>2008-10-01</p> <p>Energetic galactic cosmic ray (GCR) particles, arriving within the solar system, are modulated by the overall <span class="hlt">interplanetary</span> field carried in the solar wind. Localized disturbances related to solar activity cause further reduction in intensity, the largest being Forbush decreases in which fluxes can fall ˜20% over a few days. Understanding Forbush decreases leads to a better understanding of the <span class="hlt">magnetic</span> field structure related to shock waves and fast streams originating at the Sun since the propagation characteristics of the GCR probe much larger regions of space than do individual spacecraft instruments. We examined the temporal history of the integral GCR fluence (≥100 MeV) measured by the high-sensitivity telescope (HIST) aboard the Polar spacecraft, along with the solar wind <span class="hlt">magnetic</span> field and plasma data from the ACE spacecraft during a 40-day period encompassing the 25 September 1998 Forbush decrease. We also examined the Forbush and (energetic storm particles) ESP event on 28 October 2003. It is the use of HIST in a high-counting-rate integral mode that allows previously poorly seen, short-scale depressions in the GCR fluxes to be observed, adding crucial information on the origin of GCR modulation. Variability on time scales within the frequency range 0.001-1.0 mHz is detected. This paper concentrates on investigating four simple models for explaining short-term reductions in the GCR intensity of both small and large amplitude. Specifically, these models are a local increase in <span class="hlt">magnetic</span> scattering power, the passage of a shock discontinuity, and the passage of a tangential discontinuity or <span class="hlt">magnetic</span> rope in the solar wind plasma. Analysis of the short-scale GCR depressions during a test period in September through October 1998 shows that they are not correlated with changes in <span class="hlt">magnetic</span> scattering power or fluctuations in solar wind speed or plasma density. However, <span class="hlt">magnetic</span> field and plasma data during the test period of Forbush decrease strongly suggest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22518756-strong-solar-wind-dynamic-pressure-pulses-interplanetary-sources-impacts-geosynchronous-magnetic-fields','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22518756-strong-solar-wind-dynamic-pressure-pulses-interplanetary-sources-impacts-geosynchronous-magnetic-fields"><span>STRONG SOLAR WIND DYNAMIC PRESSURE PULSES: <span class="hlt">INTERPLANETARY</span> SOURCES AND THEIR IMPACTS ON GEOSYNCHRONOUS <span class="hlt">MAGNETIC</span> FIELDS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zuo, Pingbing; Feng, Xueshang; Wang, Yi</p> <p></p> <p>In this investigation, we first present a statistical result of the <span class="hlt">interplanetary</span> sources of very strong solar wind dynamic pressure pulses (DPPs) detected by WIND during solar cycle 23. It is found that the vast majority of strong DPPs reside within solar wind disturbances. Although the variabilities of geosynchronous <span class="hlt">magnetic</span> fields (GMFs) due to the impact of positive DPPs have been well established, there appears to be no systematic investigations on the response of GMFs to negative DPPs. Here, we study both the decompression effects of very strong negative DPPs and the compression from strong positive DPPs on GMFs atmore » different <span class="hlt">magnetic</span> local time sectors. In response to the decompression of strong negative DPPs, GMFs on the dayside near dawn and near dusk on the nightside, are generally depressed. But near the midnight region, the responses of GMF are very diverse, being either positive or negative. For part of the events when GOES is located at the midnight sector, the GMF is found to abnormally increase as the result of magnetospheric decompression caused by negative DPPs. It is known that under certain conditions <span class="hlt">magnetic</span> depression of nightside GMFs can be caused by the impact of positive DPPs. Here, we find that a stronger pressure enhancement may have a higher probability of producing the exceptional depression of GMF at the midnight region. Statistically, both the decompression effect of strong negative DPPs and the compression effect of strong positive DPPs depend on the <span class="hlt">magnetic</span> local time, which are stronger at the noon sector.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110007246&hterms=sol&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsol','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110007246&hterms=sol&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dsol"><span>Erratum to "Solar Sources and Geospace Consequences of <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Clouds Observed During Solar Cycle 23-Paper 1" [J. Atmos. Sol.-Terr. Phys. 70(2-4) (2008) 245-253</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, N.; Akiyama, S.; Yashiro, S.; Michalek, G.; Lepping, R. P.</p> <p>2009-01-01</p> <p>One of the figures (Fig. 4) in "Solar sources and geospace consequences of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> Clouds observed during solar cycle 23 -- Paper 1" by Gopalswamy et al. (2008, JASTP, Vol. 70, Issues 2-4, February 2008, pp. 245-253) is incorrect because of a software error in t he routine that was used to make the plot. The source positions of various <span class="hlt">magnetic</span> cloud (MC) types are therefore not plotted correctly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApPhL.111x3107B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApPhL.111x3107B"><span>Current control of time-<span class="hlt">averaged</span> <span class="hlt">magnetization</span> in superparamagnetic tunnel junctions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bapna, Mukund; Majetich, Sara A.</p> <p>2017-12-01</p> <p>This work investigates spin transfer torque control of time-<span class="hlt">averaged</span> <span class="hlt">magnetization</span> in a small 20 nm × 60 nm nanomagnet with a low thermal stability factor, Δ ˜ 11. Here, the nanomagnet is a part of a <span class="hlt">magnetic</span> tunnel junction and fluctuates between parallel and anti-parallel <span class="hlt">magnetization</span> states with respect to the <span class="hlt">magnetization</span> of the reference layer generating a telegraph signal in the current versus time measurements. The response of the nanomagnet to an external field is first analyzed to characterize the <span class="hlt">magnetic</span> properties. We then show that the time-<span class="hlt">averaged</span> <span class="hlt">magnetization</span> in the telegraph signal can be fully controlled between +1 and -1 by voltage over a small range of 0.25 V. NIST Statistical Test Suite analysis is performed for testing true randomness of the telegraph signal that the device generates when operated at near critical current values for spin transfer torque. Utilizing the probabilistic nature of the telegraph signal generated at two different voltages, a prototype demonstration is shown for multiplication of two numbers using an artificial AND logic gate.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...855..114J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...855..114J"><span>STEREO Observations of <span class="hlt">Interplanetary</span> Coronal Mass Ejections in 2007–2016</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jian, L. K.; Russell, C. T.; Luhmann, J. G.; Galvin, A. B.</p> <p>2018-03-01</p> <p>We have conducted a survey of 341 <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) using STEREO A/B data, analyzing their properties while extending a Level 3 product through 2016. Among the 192 ICMEs with distinguishable sheath region and <span class="hlt">magnetic</span> obstacle, the <span class="hlt">magnetic</span> field maxima in the two regions are comparable, and the dynamic pressure peaks mostly in the sheath. The north/south direction of the <span class="hlt">magnetic</span> field does not present any clear relationship between the sheath region and the <span class="hlt">magnetic</span> obstacle. About 71% of ICMEs are expanding at 1 au, and their expansion speed varies roughly linearly with their maximum speed except for ICMEs faster than 700 km s‑1. The total pressure generally peaks near the middle of the well-defined <span class="hlt">magnetic</span> cloud (MC) passage, while it often declines along with the non-MC ICME passage, consistent with our previous interpretation concerning the effects of sampling geometry on what is observed. The hourly <span class="hlt">average</span> iron charge state reaches above 12+ ∼31% of the time for MCs, ∼16% of the time for non-MC ICMEs, and ∼1% of the time for non-ICME solar wind. In four ICMEs abrupt deviations of the <span class="hlt">magnetic</span> field from the nominal field rotations occur in the <span class="hlt">magnetic</span> obstacles, coincident with a brief drop or increase in field strength—features could be related to the interaction with dust. In comparison with the similar phases of solar cycle 23, the STEREO ICMEs in this cycle occur less often and are generally weaker and slower, although their field and pressure compressions weaken less than the background solar wind.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.8037L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.8037L"><span>Electron dropout echoes induced by <span class="hlt">interplanetary</span> shock: A statistical study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Z. Y.; Zong, Q.-G.; Hao, Y. X.; Zhou, X.-Z.; Ma, X. H.; Liu, Y.</p> <p>2017-08-01</p> <p>"Electron dropout echo" as indicated by repeated moderate dropout and recovery signatures of the flux of energetic electron in the outer radiation belt region has been investigated systematically. The electron moderate dropout and its echoes are usually found for higher-energy (>300 keV) channel fluxes, whereas the flux enhancements are obvious for lower energy electrons simultaneously after the <span class="hlt">interplanetary</span> shock arrives at the Earth's geosynchronous orbit. The electron dropout echo events are found to be usually associated with the <span class="hlt">interplanetary</span> shocks arrival. The 104 dropout echo events have been found from 215 <span class="hlt">interplanetary</span> shock events from 1998 to 2007 based on the Los Alamos National Laboratory satellite data. In analogy to substorm injections, these 104 events could be naturally divided into two categories: dispersionless (49 events) or dispersive (55 events) according to the energy dispersion of the initial dropout. It is found that locations of dispersionless events are distributed mainly in the duskside magnetosphere. Further, the obtained locations derived from dispersive events with the time-of-flight technique of the initial dropout regions are mainly located at the duskside as well. Statistical studies have shown that the effect of shock normal, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field Bz and solar wind dynamic pressure may be insignificant to these electron dropout events. We suggest that the ˜1 min electric field impulse induced by the <span class="hlt">interplanetary</span> shock produces a more pronounced inward migration of electrons at the duskside, resulting in the observed duskside moderate dropout of electron flux and its consequent echoes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860056287&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DOpen%2BField','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860056287&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DOpen%2BField"><span>Ionospheric convection signatures observed by DE 2 during northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Heelis, R. A.; Hanson, W. B.; Reiff, P. H.; Winningham, J. D.</p> <p>1986-01-01</p> <p>Observations of the ionospheric convection signature at high latitudes are examined during periods of prolonged northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF). The data from Dynamics Explorer 2 show that a four-cell convection pattern can frequently be observed in a region that is displaced to the sunward side of the dawn-dusk meridian regardless of season. In the eclipsed ionosphere, extremely structured or turbulent flow exists with no identifiable connection to a more coherent pattern that may simultaneously exist in the dayside region. The two highest-latitude convection cells that form part of the coherent dayside pattern show a dependence on the y component of the IMF. This dependence is such that a clockwise circulating cell displaced toward dawn dominates the high-latitude region when B(Y) is positive. Anti-clockwise circulation displaced toward dusk dominates the highest latitudes when B(Y) is negative. Examination of the simultaneously observed energetic particle environment suggests that both open and closed field lines may be associated with the high-latitude convection cells. On occasions these entire cells can exist on open field lines. The existence of closed field lines in regions of sunward flow is also apparent in the data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SoPh..290.1371M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SoPh..290.1371M"><span>Geometrical Relationship Between <span class="hlt">Interplanetary</span> Flux Ropes and Their Solar Sources</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marubashi, K.; Akiyama, S.; Yashiro, S.; Gopalswamy, N.; Cho, K.-S.; Park, Y.-D.</p> <p>2015-05-01</p> <p>We investigated the physical connection between <span class="hlt">interplanetary</span> flux ropes (IFRs) near Earth and coronal mass ejections (CMEs) by comparing the <span class="hlt">magnetic</span> field structures of IFRs and CME source regions. The analysis is based on the list of 54 pairs of ICMEs (<span class="hlt">interplanetary</span> coronal mass ejections) and CMEs that are taken to be the most probable solar source events. We first attempted to identify the flux rope structure in each of the 54 ICMEs by fitting models with a cylinder and torus <span class="hlt">magnetic</span> field geometry, both with a force-free field structure. This analysis determined the possible geometries of the identified flux ropes. Then we compared the flux rope geometries with the <span class="hlt">magnetic</span> field structure of the solar source regions. We obtained the following results: (1) Flux rope structures are seen in 51 ICMEs out of the 54. The result implies that all ICMEs have an intrinsic flux rope structure, if the three exceptional cases are attributed to unfavorable observation conditions. (2) It is possible to find flux rope geometries with the main axis orientation close to the orientation of the <span class="hlt">magnetic</span> polarity inversion line (PIL) in the solar source regions, the differences being less than 25°. (3) The helicity sign of an IFR is strongly controlled by the location of the solar source: flux ropes with positive (negative) helicity are associated with sources in the southern (northern) hemisphere (six exceptions were found). (4) Over two-thirds of the sources in the northern hemisphere are concentrated along PILs with orientations of 45° ± 30° (measured clockwise from the east), and over two-thirds in the southern hemisphere along PILs with orientations of 135° ± 30°, both corresponding to the Hale boundaries. These results strongly support the idea that a flux rope with the main axis parallel to the PIL erupts in a CME and that the erupted flux rope propagates through the <span class="hlt">interplanetary</span> space with its orientation maintained and is observed as an IFR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JGR...10525143R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JGR...10525143R"><span>The <span class="hlt">interplanetary</span> shock of September 24, 1998: Arrival at Earth</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Russell, C. T.; Wang, Y. L.; Raeder, J.; Tokar, R. L.; Smith, C. W.; Ogilvie, K. W.; Lazarus, A. J.; Lepping, R. P.; Szabo, A.; Kawano, H.; Mukai, T.; Savin, S.; Yermolaev, Y. I.; Zhou, X.-Y.; Tsurutani, B. T.</p> <p>2000-11-01</p> <p>At close to 2345 UT on September 24, 1998, the magnetosphere was suddenly compressed by the passage of an <span class="hlt">interplanetary</span> shock. In order to properly interpret the magnetospheric events triggered by the arrival of this shock, we calculate the orientation of the shock, its velocity, and its estimated time of arrival at the nose of the magnetosphere. Our best fit shock normal has an orientation of (-0.981 -0.157 -0.112) in solar ecliptic coordinates, a speed of 769 km/s, and an arrival time of 2344:19 at the magnetopause at 10 RE. Since measurements of the solar wind and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field are available from multiple spacecraft, we can compare several different techniques of shock-normal determination. Of the single spacecraft techniques the <span class="hlt">magnetic</span> coplanarity solution is most accurate and the mixed mode solution is of lesser accuracy. Uncertainty in the timing and location of the IMP 8 spacecraft limits the accuracy of solutions using the time of arrival at the position of IMP 8.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080036103&hterms=maxima&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmaxima','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080036103&hterms=maxima&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmaxima"><span>CAWSES November 7-8, 2004, Superstorm: Complex Solar and <span class="hlt">Interplanetary</span> Features in the Post-Solar Maximum Phase</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tsurutani, Bruce T.; Echer, Ezequiel; Guarnieri, Fernando L.; Kozyra, J. U.</p> <p>2008-01-01</p> <p>The complex <span class="hlt">interplanetary</span> structures during 7 to 8 Nov 2004 are analyzed to identify their properties as well as resultant geomagnetic effects and the solar origins. Three fast forward shocks, three directional discontinuities and two reverse waves were detected and analyzed in detail. The three fast forward shocks 'pump' up the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field from a value of approx.4 nT to 44 nT. However, the fields after the shocks were northward, and <span class="hlt">magnetic</span> storms did not result. The three ram pressure increases were associated with major sudden impulses (SI + s) at Earth. A <span class="hlt">magnetic</span> cloud followed the third forward shock and the southward Bz associated with the latter was responsible for the superstorm. Two reverse waves were detected, one at the edge and one near the center of the <span class="hlt">magnetic</span> cloud (MC). It is suspected that these 'waves' were once reverse shocks which were becoming evanescent when they propagated into the low plasma beta MC. The second reverse wave caused a decrease in the southward component of the IMF and initiated the storm recovery phase. It is determined that flares located at large longitudinal distances from the subsolar point were the most likely causes of the first two shocks without associated <span class="hlt">magnetic</span> clouds. It is thus unlikely that the shocks were 'blast waves' or that <span class="hlt">magnetic</span> reconnection eroded away the two associated MCs. This <span class="hlt">interplanetary</span>/solar event is an example of the extremely complex <span class="hlt">magnetic</span> storms which can occur in the post-solar maximum phase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110007245&hterms=Butterfly&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DButterfly','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110007245&hterms=Butterfly&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DButterfly"><span>Solar Sources and Geospace Consequences of <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Clouds Observed During Solar Cycle 23</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, N.; Akiyama, S.; Yashiro, S.; Michalek, G.; Lepping, R. P.</p> <p>2007-01-01</p> <p>We present results of a statistical investigation of 99 <span class="hlt">magnetic</span> clouds (MCs) observed during 1995-2005. The MC-associated coronal mass ejections (CMEs) are faster and wider on the <span class="hlt">average</span> and originate within +/-30deg from the solar disk center. The solar sources of MCs also followed the butterfly diagram. The correlation between the <span class="hlt">magnetic</span> field strength and speed of MCs was found to be valid over a much wider range of speeds. The number of south-north (SN) MCs was dominant and decreased with solar cycle, while the number of north-south (NS) MCs increased confirming the odd-cycle behavior. Two-thirds of MCs were geoeffective; the Dst index was highly correlated with speed and <span class="hlt">magnetic</span> field in MCs as well as their product. Many (55%) fully northward (FN) MCs were geoeffective solely due to their sheaths. The non-geoeffective MCs were slower (<span class="hlt">average</span> speed approx. 382 km/s), had a weaker southward <span class="hlt">magnetic</span> field (<span class="hlt">average</span> approx. -5.2nT), and occurred mostly during the rise phase of the solar activity cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20100026445&hterms=figueroa&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dfigueroa','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20100026445&hterms=figueroa&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dfigueroa"><span>Propagation and Evolution of CMEs in the <span class="hlt">Interplanetary</span> Medium: Analysis of Remote Sensing and In situ Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Figueroa-Vinas, Adolfo; Nieves-Chinchilla, Teresa; Vourlidas, Angelos; Gomez-Herrero, Raul; Malandraki, Olga; Szabo, Adam; Dresing, Nina; Davila, Joseph M.</p> <p>2010-01-01</p> <p>EUV disk imagers and white light coronagraphs have provided for many years information on the early formation and evolution of corona) mass ejections (CMEs). More recently, the novel heliospheric imaging instruments aboard the STEREO mission are providing crucial remote sensing information on the <span class="hlt">interplanetary</span> evolution of these events while in situ instruments complete the overall characterization of the <span class="hlt">interplanetary</span> CMEs. In this work, we present an analysis of CMEs from the Sun to the <span class="hlt">interplanetary</span> medium using combined data from THE SOHO, STEREO, WIND, and ACE spacecraft. The events were selected to cover the widest possible spectrum of different ambient solar wind, <span class="hlt">magnetic</span> field configurations, plasma parameters, etc. to allow uncovering those aspects that are important in understanding the propagation and evolution mechanisms of CMEs in the <span class="hlt">interplanetary</span> medium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770018265','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770018265"><span><span class="hlt">Interplanetary</span> Physics Laboratory (IPL): A concept for an <span class="hlt">interplanetary</span> mission in the mid-eighties</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burlaga, L. F.; Ogilvie, K. W.; Feldman, W.</p> <p>1977-01-01</p> <p>A concept for a near-earth <span class="hlt">interplanetary</span> mission in the mid-eighties is described. The proposed objectives would be to determine the composition of the <span class="hlt">interplanetary</span> constituents and its dependence on source-conditions and to investigate energy and momentum transfer processes in the <span class="hlt">interplanetary</span> medium. Such a mission would accomplish three secondary objectives: (1) provide a baseline for deep space missions, (2) investigate variations of the solar wind with solar activity, and (3) provide input functions for magnetospheric studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021344&hterms=geofisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dgeofisica','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021344&hterms=geofisica&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dgeofisica"><span>The emergence of different polarity photospheric flux as the cause of CMEs and <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bravo, S.</p> <p>1995-01-01</p> <p>Here we discuss the effect that the emergence of flux with a polarity opposed to that previously established in a certain photospheric region. can have on the <span class="hlt">magnetic</span> structure of the solar atmosphere. We show that such a flux emergence may lead to the ejection of coronal material into the <span class="hlt">interplanetary</span> medium (a CME) and also to a rapid change in the velocity of the solar wind from the region, which may eventually lead to the formation of an <span class="hlt">interplanetary</span> shock.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMSM11B2290V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMSM11B2290V"><span>Sector structure of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field in the second half of the 19th century inferred from ground-based magnetometers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vokhmyanin, M.; Ponyavin, D. I.</p> <p>2012-12-01</p> <p><span class="hlt">Interplanetary</span> <span class="hlt">magnetic</span> field (IMF) polarities can be inferred in the pre-satellite era using Svalgaard-Mansurov effect, according to which different IMF directions lead to different geomagnetic variations at polar stations. Basing on this effect we propose a method to derive a sector structure of the IMF when only ground based data are available. Details of the method and results have been presented in our recent paper: Vokhmyanin, M. V., and D. I. Ponyavin (2012), Inferring <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field polarities from geomagnetic variations, J. Geophys. Res., 117, A06102, doi:10.1029/2011JA017060. Using data from eight stations: Sitka, Sodankyla, Godhavn, Lerwick, Thule, Baker Lake, Vostok and Mirny, we reconstructed sector structure back to 1905. The quality of inferring from 1965 to 2005 ranges between 78% and 90% depending on the used set of stations. Our results show both high success rate and good agreement with the well-known Russell-McPherron and Rosenberg-Coleman effects. In the current study we applied the technique to historical data of Helsinki observatory where digital versions of hourly geomagnetic components are available from 1844 to 1897. Helsinki station stopped operates at the beginning of 20th century. Thus, to create a model describing the local Svalgaard-Mansurov effect we analyzed data from Nurmijarvi station located near the same region. The success rate of reconstruction from 1965 to 2005 is around 82%. So we assume that the IMF polarities obtained for the period 1869-1889 have sufficient quality. Inferred sector structure at this time consists of two sectors typically for all declining phases of solar activity cycle. Catalogue of IMF proxies seem to be important in analyzing structure and dynamics of solar <span class="hlt">magnetic</span> fields in the past.; Left: Bartels diagram of IMF sector structure inferred from Helsinki data. Right: sunspot number indicating solar cycles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840005037','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840005037"><span>The <span class="hlt">average</span> solar wind in the inner heliosphere: Structures and slow variations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schwenn, R.</p> <p>1983-01-01</p> <p>Measurements from the HELIOS solar probes indicated that apart from solar activity related disturbances there exist two states of the solar wind which might result from basic differences in the acceleration process: the fast solar wind (v 600 kms(-)1) emanating from <span class="hlt">magnetically</span> open regions in the solar corona and the "slow" solar wind (v 400 kms(-)1) correlated with the more active regions and its mainly closed <span class="hlt">magnetic</span> structures. In a comprehensive study using all HELIOS data taken between 1974 and 1982 the <span class="hlt">average</span> behavior of the basic plasma parameters were analyzed as functions of the solar wind speed. The long term variations of the solar wind parameters along the solar cycle were also determined and numerical estimates given. These modulations appear to be distinct though only minor. In agreement with earlier studies it was concluded that the major modulations are in the number and size of high speed streams and in the number of <span class="hlt">interplanetary</span> shock waves caused by coronal transients. The latter ones usually cause huge deviations from the <span class="hlt">averages</span> of all parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22521951-energetic-particle-pressure-interplanetary-shocks-stereo-observations','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22521951-energetic-particle-pressure-interplanetary-shocks-stereo-observations"><span>ENERGETIC PARTICLE PRESSURE AT <span class="hlt">INTERPLANETARY</span> SHOCKS: STEREO-A OBSERVATIONS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Lario, D.; Decker, R. B.; Roelof, E. C.</p> <p>2015-11-10</p> <p>We study periods of elevated energetic particle intensities observed by STEREO-A when the partial pressure exerted by energetic (≥83 keV) protons (P{sub EP}) is larger than the pressure exerted by the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (P{sub B}). In the majority of cases, these periods are associated with the passage of <span class="hlt">interplanetary</span> shocks. Periods when P{sub EP} exceeds P{sub B} by more than one order of magnitude are observed in the upstream region of fast <span class="hlt">interplanetary</span> shocks where depressed <span class="hlt">magnetic</span> field regions coincide with increases of energetic particle intensities. When solar wind parameters are available, P{sub EP} also exceeds the pressure exertedmore » by the solar wind thermal population (P{sub TH}). Prolonged periods (>12 hr) with both P{sub EP} > P{sub B} and P{sub EP} > P{sub TH} may also occur when energetic particles accelerated by an approaching shock encounter a region well upstream of the shock characterized by low <span class="hlt">magnetic</span> field magnitude and tenuous solar wind density. Quasi-exponential increases of the sum P{sub SUM} = P{sub B} + P{sub TH} + P{sub EP} are observed in the immediate upstream region of the shocks regardless of individual changes in P{sub EP}, P{sub B}, and P{sub TH}, indicating a coupling between P{sub EP} and the pressure of the background medium characterized by P{sub B} and P{sub TH}. The quasi-exponential increase of P{sub SUM} implies a radial gradient ∂P{sub SUM}/∂r > 0 that is quasi-stationary in the shock frame and results in an outward force applied to the plasma upstream of the shock. This force can be maintained by the mobile energetic particles streaming upstream of the shocks that, in the most intense events, drive electric currents able to generate diamagnetic cavities and depressed solar wind density regions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38.1924W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38.1924W"><span>Imaging <span class="hlt">Interplanetary</span> CMEs at Radio Frequency From Solar Polar Orbit</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Ji; Sun, Weiying; Zheng, Jianhua; Zhang, Cheng; Wang, Chi; Wang, C. B.; Wang, S.</p> <p></p> <p>Coronal mass ejections (CMEs) are violent discharges of plasma and <span class="hlt">magnetic</span> fields from the Sun's corona. They have come to be recognized as the major driver of physical conditions in the Sun-Earth system. Consequently, the detection of CMEs is important for un-derstanding and ultimately predicting space weather conditions. The Solar Polar Orbit Radio Telescope (SPORT) is a proposed mission to observe the propagation of <span class="hlt">interplanetary</span> CMEs from solar polar orbit. The main payload (radio telescope) on board SPORT will be an in-terferometric imaging radiometer working at the meter wavelength band, which will follow the propagation of <span class="hlt">interplanetary</span> CMEs from a distance of a few solar radii to near 1 AU from solar polar orbit. The SPORT spacecraft will also be equipped with a set of optical and in situ measurement instruments such as a EUV solar telescope, a solar wind plasma experiment, a solar wind ion composition instrument, an energetic particle detector, a wave detector, a mag-netometer and an <span class="hlt">interplanetary</span> radio burst tracker. In this paper, we first describe the current shortage of <span class="hlt">interplanetary</span> CME observations. Next, the scientific motivation and objectives of SPORT are introduced. We discuss the basic specifications of the main radio telescope of SPORT with reference to the radio emission mechanisms and the radio frequency band to be observed. Finally, we discuss the key technologies of the SPORT mission, including the con-ceptual design of the main telescope, the image retrieval algorithm and the solar polar orbit injection. Other payloads and their respective observation objectives are also briefly discussed. Key words: <span class="hlt">Interplanetary</span> CMEs; Interferometric imaging; Solar polar orbit; Radiometer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950056921&hterms=Magnetic+Flux&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DMagnetic%2BFlux','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950056921&hterms=Magnetic+Flux&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DMagnetic%2BFlux"><span>Cross-tail <span class="hlt">magnetic</span> flux ropes as observed by the GEOTAIL spacecraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lepping, R. P.; Fairfield, D. H.; Jones, J.; Frank, L. A.; Paterson, W. R.; Kokubun, S.; Yamamoto, T.</p> <p>1995-01-01</p> <p>Ten transient <span class="hlt">magnetic</span> structures in Earth's magnetotail, as observed in GEOTAIL measurements, selected for early 1993 (at (-) X(sub GSM) = 90 - 130 Earth radii), are shown to have helical <span class="hlt">magnetic</span> field configurations similar to those of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds at 1 AU but smaller in size by a factor of approximately = 700. Such structures are shown to be well approximated by a comprehensive <span class="hlt">magnetic</span> force-free flux-rope model. For this limited set of 10 events the rope axes are seen to be typically aligned with the Y(sub GSM) axis and the <span class="hlt">average</span> diameter of these structures is approximately = 15 Earth radii.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120009629','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120009629"><span>Electromagnetic Whistler Precursors at Supercritical <span class="hlt">Interplanetary</span> Shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, L. B., III</p> <p>2012-01-01</p> <p>We present observations of electromagnetic precursor waves, identified as whistler mode waves, at supercritical <span class="hlt">interplanetary</span> shocks using the Wind search coil magnetometer. The precursors propagate obliquely with respect to the local <span class="hlt">magnetic</span> field, shock normal vector, solar wind velocity, and they are not phase standing structures. All are right-hand polarized with respect to the <span class="hlt">magnetic</span> field (spacecraft frame), and all but one are right-hand polarized with respect to the shock normal vector in the normal incidence frame. Particle distributions show signatures of specularly reflected gyrating ions, which may be a source of free energy for the observed modes. In one event, we simultaneously observe perpendicular ion heating and parallel electron acceleration, consistent with wave heating/acceleration due to these waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830025541','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830025541"><span>Electron heating at <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Feldman, W. C.; Asbridge, J. R.; Bame, S. J.; Gosling, J. T.; Zwickl, R. D.</p> <p>1982-01-01</p> <p>Data for 41 forward <span class="hlt">interplanetary</span> shocks show that the ratio of downstream to upstream electron temperatures, T/sub e/(d/u) is variable in the range between 1.0 (isothermal) and 3.0. On <span class="hlt">average</span>, (T/sub e/(d/u) = 1.5 with a standard deviation, sigma e = 0.5. This ratio is less than the <span class="hlt">average</span> ratio of proton temperatures across the same shocks, (T/sub p/(d/u)) = 3.3 with sigma p = 2.5 as well as the <span class="hlt">average</span> ratio of electron temperatures across the Earth's bow shock. Individual samples of T/sub e/(d/u) and T/sub p/(d/u) appear to be weakly correlated with the number density ratio. However the amounts of electron and proton heating are well correlated with each other as well as with the bulk velocity difference across each shock. The stronger shocks appear to heat the protons relatively more efficiently than they heat the electrons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1424N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1424N"><span>Differences in generation of <span class="hlt">magnetic</span> storms driven by <span class="hlt">magnetic</span> clouds, ejecta, sheath region before ICME and CIR</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nikolaeva, Nadezhda; Yermolaev, Yuri; Lodkina, Irina</p> <p>2016-07-01</p> <p>We investigate the efficiency of main phase storm generation by different solar wind (SW) streams when using 12 functions coupling (FC) various <span class="hlt">interplanetary</span> parameters with magnetospheric state. By using our Catalog of Solar Wind Phenomena [Yermolaev et al., 2009] created on the basis of the OMNI database for 1976-2000, we selected the <span class="hlt">magnetic</span> storms with Dst ≤ -50 nT for which <span class="hlt">interplanetary</span> sources were following: MC (10 storms); Ejecta (31 storms); Sheath (21 storms); CIRs (31<span class="hlt">magnetic</span> storms). To compare the <span class="hlt">interplanetary</span> drivers we estimate an efficiency of <span class="hlt">magnetic</span> storm generation by type of solar wind stream with using 12 coupling functions. We obtained that in <span class="hlt">average</span> Sheath has more large efficiency of the <span class="hlt">magnetic</span> storm generation and MC has more low efficiency in agreement with our previous results which show that by using a modification of formula by Burton et al. [1975] for connection of <span class="hlt">interplanetary</span> conditions with Dst and Dst* indices the efficiency of storm generation by Sheath and CIR was ~50% higher than generation by ICME [Nikolaeva et al., 2013; 2015]. The most part of FCs has sufficiently high correlation coefficients. In particular the highest values of coefficients (~ 0.5 up to 0.63) are observed for Sheath- driven storms. In a small part of FCs with low coefficients it is necessary to increase the number of <span class="hlt">magnetic</span> storms to increase the statistical significance of results. The reliability of the obtained data and possible reasons of divergences for various FCs and various SW types require further researches. The authors are grateful for the opportunity to use the OMNI database. This work was supported by the Russian Foundation for Basic Research, project 16-02-00125, and by Program of Presidium of the Russian Academy of Sciences. References: Nikolaeva, N. S., Y. I. Yermolaev, and I. G. Lodkina (2013), Modeling of Dst-index temporal profile on the main phase of the <span class="hlt">magnetic</span> storms generated by different types of solar wind, Cosmic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JASS...30..101O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JASS...30..101O"><span>Variation of Solar, <span class="hlt">Interplanetary</span> and Geomagnetic Parameters during Solar Cycles 21-24</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oh, Suyeon; Kim, Bogyeong</p> <p>2013-06-01</p> <p>The length of solar cycle 23 has been prolonged up to about 13 years. Many studies have speculated that the solar cycle 23/24 minimum will indicate the onset of a grand minimum of solar activity, such as the Maunder Minimum. We check the trends of solar (sunspot number, solar <span class="hlt">magnetic</span> fields, total solar irradiance, solar radio flux, and frequency of solar X-ray flare), <span class="hlt">interplanetary</span> (<span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, solar wind and galactic cosmic ray intensity), and geomagnetic (Ap index) parameters (SIG parameters) during solar cycles 21-24. Most SIG parameters during the period of the solar cycle 23/24 minimum have remarkably low values. Since the 1970s, the space environment has been monitored by ground observatories and satellites. Such prevalently low values of SIG parameters have never been seen. We suggest that these unprecedented conditions of SIG parameters originate from the weakened solar <span class="hlt">magnetic</span> fields. Meanwhile, the deep 23/24 solar cycle minimum might be the portent of a grand minimum in which the global mean temperature of the lower atmosphere is as low as in the period of Dalton or Maunder minimum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880003642','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880003642"><span>The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for <span class="hlt">interplanetary</span> fusions propulsion applications</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Orth, Charles D.; Klein, Gail; Sercel, Joel; Hoffman, Nate; Murray, Kathy; Chang-Diaz, Franklin</p> <p>1987-01-01</p> <p>Inertial Confinement Fusion (ICF) is an attractive engine power source for <span class="hlt">interplanetary</span> manned spacecraft, especially for near-term missions requiring minimum flight duration, because ICF has inherent high power-to-mass ratios and high specific impulses. We have developed a new vehicle concept called VISTA that uses ICF and is capable of round-trip manned missions to Mars in 100 days using A.D. 2020 technology. We describe VISTA's engine operation, discuss associated plasma issues, and describe the advantages of DT fuel for near-term applications. Although ICF is potentially superior to non-fusion technologies for near-term <span class="hlt">interplanetary</span> transport, the performance capabilities of VISTA cannot be meaningfully compared with those of <span class="hlt">magnetic</span>-fusion systems because of the lack of a comparable study of the <span class="hlt">magnetic</span>-fusion systems. We urge that such a study be conducted.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22661344-propagation-characteristics-two-coronal-mass-ejections-from-sun-far-interplanetary-space','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22661344-propagation-characteristics-two-coronal-mass-ejections-from-sun-far-interplanetary-space"><span>Propagation Characteristics of Two Coronal Mass Ejections from the Sun Far into <span class="hlt">Interplanetary</span> Space</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zhao, Xiaowei; Liu, Ying D.; Hu, Huidong</p> <p></p> <p>Propagation of coronal mass ejections (CMEs) from the Sun far into <span class="hlt">interplanetary</span> space is not well understood, due to limited observations. In this study we examine the propagation characteristics of two geo-effective CMEs, which occurred on 2005 May 6 and 13, respectively. Significant heliospheric consequences associated with the two CMEs are observed, including <span class="hlt">interplanetary</span> CMEs (ICMEs) at the Earth and Ulysses , <span class="hlt">interplanetary</span> shocks, a long-duration type II radio burst, and intense geomagnetic storms. We use coronagraph observations from SOHO /LASCO, frequency drift of the long-duration type II burst, in situ measurements at the Earth and Ulysses , and magnetohydrodynamicmore » propagation of the observed solar wind disturbances at 1 au to track the CMEs from the Sun far into <span class="hlt">interplanetary</span> space. We find that both of the CMEs underwent a major deceleration within 1 au and thereafter a gradual deceleration when they propagated from the Earth to deep <span class="hlt">interplanetary</span> space, due to interactions with the ambient solar wind. The results also reveal that the two CMEs interacted with each other in the distant <span class="hlt">interplanetary</span> space even though their launch times on the Sun were well separated. The intense geomagnetic storm for each case was caused by the southward <span class="hlt">magnetic</span> fields ahead of the CME, stressing the critical role of the sheath region in geomagnetic storm generation, although for the first case there is a corotating interaction region involved.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002cosp...34E.520X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002cosp...34E.520X"><span>Forecast the energetic electron flux on geosynchronous orbit with <span class="hlt">interplanetary</span> parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xue, B.; Ye, Z.</p> <p></p> <p>The high flux of energetic electron on geo-synchronous orbit can cause many kinds of malfunction of the satellite there, within which the bulk charging is the most significant that several broadcast satellite failures were confirmed to be due to this effect. The electron flux on geo-synchronous orbit varies in a large range even up to three orders accompanied the passage of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> cloud and the following geomagnetic disturbances. Upon investigating electron flux, <span class="hlt">interplanetary</span> solar wind data, and geomagnetic data as well, we found that: (1) The enhancement of energetic flux on the geo-synchronous orbit exhibits periodic recurrence of 27days. (2)Significant increase of electron flux relates to <span class="hlt">interplanetary</span> index and characters of their distribution. (3)The electron flux also has relation to solar activity index. In our research work, artificial neural network was employed and constructed according to the job. The neural network, we call it full connecting network, was proved to be a sufficient tool to analyze the character of the evolving parameters, remember the omen of "electron storm", and establish the relationship between <span class="hlt">interplanetary</span> parameters etc., and the fluence of high energetic electrons. The neural network was carefully constructed and trained to do the job mentioned above. Preliminary result showed that the accuracy forecast of electron flux 1 day ahead can reach 80%, and 70% for 2 days ahead.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780013752','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780013752"><span>On the <span class="hlt">average</span> configuration of the geomagnetic tail</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fairfield, D. H.</p> <p>1978-01-01</p> <p>Over 3000 hours of IMP-6 <span class="hlt">magnetic</span> field data obtained between 20 and 33 R sub E in the geomagnetic tail have been used in a statistical study of the tail configuration. A distribution of 2.5 minute <span class="hlt">averages</span> of B sub Z as a function of position across the tail reveals that more flux crosses the equatorial plane near the dawn and dusk flanks than near midnight. The tail field projected in the solar magnetospheric equatorial plane deviates from the X axis due to flaring and solar wind aberration by an angle alpha = -0.9 y sub SM - 1.7 where Y sub SM is in earth radii and alpha is in degrees. After removing these effects the Y component of the tail field is found to depend on <span class="hlt">interplanetary</span> sector structure. During an away sector the B sub Y component of the tail field is on <span class="hlt">average</span> 0.5 gamma greater than that during a toward sector, a result that is true in both tail lobes and is independent of location across the tail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730002072','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730002072"><span><span class="hlt">Interplanetary</span> double-shock ensembles with anomalous electrical conductivity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dryer, M.</p> <p>1972-01-01</p> <p>Similarity theory is applied to the case of constant velocity, piston-driven, shock waves. This family of solutions, incorporating the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field for the case of infinite electric conductivity, represents one class of experimentally observed, flare-generated shock waves. This paper discusses the theoretical extension to flows with finite conductivity (presumably caused by unspecified modes of wave-particle interactions). Solutions, including reverse shocks, are found for a wide range of <span class="hlt">magnetic</span> Reynolds numbers from one to infinity. Consideration of a zero and nonzero ambient flowing solar wind (together with removal of <span class="hlt">magnetic</span> considerations) enables the recovery of earlier similarity solutions as well as numerical simulations. A limited comparison with observations suggests that flare energetics can be reasonably estimated once the shock velocity, ambient solar wind velocity and density, and ambient azimuthal Alfven Mach number are known.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110007813&hterms=electrostatics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Delectrostatics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110007813&hterms=electrostatics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Delectrostatics"><span>Large-Amplitude Electrostatic Waves Observed at a Supercritical <span class="hlt">Interplanetary</span> Shock</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, L. B., III; Cattell, C. A.; Kellogg, P. J.; Goetz, K.; Kersten, K.; Kasper, J. C.; Szabo, A.; Wilber, M.</p> <p>2010-01-01</p> <p>We present the first observations at an <span class="hlt">interplanetary</span> shock of large-amplitude (> 100 mV/m pk-pk) solitary waves and large-amplitude (approx.30 mV/m pk-pk) waves exhibiting characteristics consistent with electron Bernstein waves. The Bernstein-like waves show enhanced power at integer and half-integer harmonics of the cyclotron frequency with a broadened power spectrum at higher frequencies, consistent with the electron cyclotron drift instability. The Bernstein-like waves are obliquely polarized with respect to the <span class="hlt">magnetic</span> field but parallel to the shock normal direction. Strong particle heating is observed in both the electrons and ions. The observed heating and waveforms are likely due to instabilities driven by the free energy provided by reflected ions at this supercritical <span class="hlt">interplanetary</span> shock. These results offer new insights into collisionless shock dissipation and wave-particle interactions in the solar wind.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010294','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010294"><span>Source Regions of the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field and Variability in Heavy-Ion Elemental Composition in Gradual Solar Energetic Particle Events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ko, Yuan-Kuen; Tylka, Allan J.; Ng, Chee K.; Wang, Yi-Ming; Dietrich, William F.</p> <p>2013-01-01</p> <p>Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass-ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. But an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the PFSS model to map the Sun-L1 <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) line back to its source region on the Sun at the time of the SEP observations; and (2) then look for correlation between SEP composition (as measured by Wind and ACE at approx. 2-30 MeV/nucleon) and characteristics of the identified IMF-source regions. The study is based on 24 SEP events, identified as a statistically-significant increase in approx. 20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly-emergent solar <span class="hlt">magnetic</span> flux and CMEs was lower than in solar-maximum years and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF-source, with the largest enhancements occurring when the footpoint field is strong, due to the nearby presence of an active region. In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering, at least on <span class="hlt">average</span>, similar to that found in impulsive events. These results lead us to suggest that <span class="hlt">magnetic</span> reconnection in footpoint regions near active regions bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMSM31D4239M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMSM31D4239M"><span>The Ring Current Response to Solar and <span class="hlt">Interplanetary</span> Storm Drivers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mouikis, C.; Kistler, L. M.; Bingham, S.; Kronberg, E. A.; Gkioulidou, M.; Huang, C. L.; Farrugia, C. J.</p> <p>2014-12-01</p> <p>The ring current responds differently to the different solar and <span class="hlt">interplanetary</span> storm drivers such as coronal mass injections, (CME's), corotating interaction regions (CIR's), high-speed streamers and other structures. The resulting changes in the ring current particle pressure, in turn, change the global <span class="hlt">magnetic</span> field, controlling the transport of the radiation belts. To quantitatively determine the field changes during a storm throughout the magnetosphere, it is necessary to understand the transport, sources and losses of the particles that contribute to the ring current. Because the measured ring current energy spectra depend not only on local processes, but also on the history of the ions along their entire drift path, measurements of ring current energy spectra at two or more locations can be used to strongly constrain the time dependent <span class="hlt">magnetic</span> and electric fields. In this study we use data predominantly from the Cluster and the Van Allen Probes, covering more than a full solar cycle (from 2001 to 2014). For the period 2001-2012, the Cluster CODIF and RAPID measurements of the inner magnetosphere are the primary data set used to monitor the storm time ring current variability. After 2012, the Cluster data set complements the data from the Van Allen Probes HOPE and RBSPICE instruments, providing additional measurements from different MLT and L shells. Selected storms from this periods, allow us to study the ring current dynamics and pressure changes, as a function of L shell, <span class="hlt">magnetic</span> local time, and the type of <span class="hlt">interplanetary</span> disturbances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730053720&hterms=Separation+powers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DSeparation%2Bof%2Bpowers','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730053720&hterms=Separation+powers&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DSeparation%2Bof%2Bpowers"><span>The rate of separation of <span class="hlt">magnetic</span> lines of force in a random <span class="hlt">magnetic</span> field.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jokipii, J. R.</p> <p>1973-01-01</p> <p>The mixing of <span class="hlt">magnetic</span> lines of force, as represented by their rate of separation, as a function of distance along the <span class="hlt">magnetic</span> field, is considered with emphasis on neighboring lines of force. This effect is particularly important in understanding the transport of charged particles perpendicular to the <span class="hlt">average</span> <span class="hlt">magnetic</span> field. The calculation is carried out in the approximation that the separation changes by an amount small compared with the correlation scale normal to the field, in a distance along the field of a few correlation scales. It is found that the rate of separation is very sensitive to the precise form of the power spectrum. Application to the <span class="hlt">interplanetary</span> and interstellar <span class="hlt">magnetic</span> fields is discussed, and it is shown that in some cases field lines, much closer together than the correlation scale, separate at a rate which is effectively as rapid as if they were many correlation lengths apart.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFMSH41A1626N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFMSH41A1626N"><span>PROPAGATION AND EVOLUTION OF THE JUNE 1st 2008 CME IN THE <span class="hlt">INTERPLANETARY</span> MEDIUM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nieves-Chinchilla, T.; Lamb, D. A.; Davila, J. M.; Vinas, A. F.; Moestl, C.; Hidalgo, M. A.; Farrugia, C. J.; Malandraki, O.; Dresing, N.; Gómez-Herrero, R.</p> <p>2009-12-01</p> <p>In this work we present a study of the coronal mass ejection (CME) of June 1st of 2008 in the <span class="hlt">interplanetary</span> medium. This event has been extensively studied by others because of its favorable geometry and the possible consequences of its peculiar initiation for space weather forecasting. We show an analysis of the evolution of the CME in the <span class="hlt">interplanetary</span> medium in order to shed some light on the propagation mechanism of the ICME. We have determined the typical shock associated characteristics of the ICME in order to understand the propagation properties. Using two different non force-free models of the <span class="hlt">magnetic</span> cloud allows us to incorporate expansion of the cloud. We use in-situ measurements from STEREO B/IMPACT to characterize the ICME. In addition, we use images from STEREO A/SECCHI-HI to analyze the propagation and visual evolution of the associated flux rope in the <span class="hlt">interplanetary</span> medium. We compare and contrast these observations with the results of the analytical models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900020833','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900020833"><span><span class="hlt">Interplanetary</span> medium data book, supplement 4, 1985-1988</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>King, Joseph H.</p> <p>1989-01-01</p> <p>An extension is presented of the series of <span class="hlt">Interplanetary</span> Medium Data Books and supplements which have been issued by the National Space Science Data Center since 1977. This volume contains solar wind <span class="hlt">magnetic</span> field (IMF) and plasma data from the IMP 8 spacecraft for 1985 to 1988, and 1985 IMF data from the Czechoslovakian Soviet Prognoz 10 spacecraft. The normalization of the MIT plasma density and temperature, which has been discussed at length in previous volumes, is implemented as before, using the same normalization constants for 1985 to 1988 data as for the earlier data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JPhCS.409a2177P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JPhCS.409a2177P"><span>Transparency of a <span class="hlt">magnetic</span> cloud boundary for cosmic rays</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petukhov, I. S.; Petukhov, S. I.</p> <p>2013-02-01</p> <p>We have suggested a model of <span class="hlt">magnetic</span> cloud presented as a torus with <span class="hlt">magnetic</span> flux rope structure situated inside the <span class="hlt">interplanetary</span> corona mass ejecta expanding radially away from the Sun through the <span class="hlt">interplanetary</span> medium. The <span class="hlt">magnetic</span> field of the torus changing during its propagation has been obtained. The <span class="hlt">magnetic</span> cloud — solar wind boundary transparency for cosmic rays with different energies depending on the cloud orientation and properties of the torus <span class="hlt">magnetic</span> field has been determined by means of calculation of the particle trajectories at the boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSH32B..05T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSH32B..05T"><span>Source Regions of the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field and Variability in Heavy-Ion Elemental Composition in Gradual Solar Energetic Particle Events (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tylka, A. J.; Ko, Y.; Ng, C. K.; Wang, Y.; Dietrich, W. F.</p> <p>2013-12-01</p> <p>Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass-ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. But an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the PFSS model to map the Sun-L1 <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) line back to its source region on the Sun at the time of the SEP observations; and (2) then look for correlation between SEP composition (as measured by Wind and ACE at ~2-30 MeV/nucleon) and characteristics of the identified IMF-source regions. The study is based on 24 SEP events, identified as a statistically-significant increase in ~20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly-emergent solar <span class="hlt">magnetic</span> flux and CMEs was lower than in solar-maximum years and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF-source, with the largest enhancements occurring when the footpoint field is strong, due to the nearby presence of an active region. In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering, at least on <span class="hlt">average</span>, similar to that found in impulsive events. These results lead us to suggest that <span class="hlt">magnetic</span> reconnection in footpoint regions near active regions bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850035908&hterms=Electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DElectric%2Bcurrent','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850035908&hterms=Electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3DElectric%2Bcurrent"><span>The <span class="hlt">interplanetary</span> electric field, cleft currents and plasma convection in the polar caps</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Banks, P. M.; Clauer, C. R.; Araki, T.; St. Maurice, J. P.; Foster, J. C.</p> <p>1984-01-01</p> <p>The relationship between the pattern of plasma convection in the polar cleft and the dynamics of the <span class="hlt">interplanetary</span> electric field (IEF) is examined theoretically. It is shown that owing to the geometrical properties of the magnetosphere, the East-West component of the IEF will drive field-aligned currents which connect to the ionosphere at points lying on either side of noon, while currents associated with the North-South component of the IEF will connect the two polar caps as sheet currents, also centered at 12 MLT. In order to describe the consequences of the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field (IMF) effects upon high-latitude electric fields and convection patterns, a series of numerical simulations was carried out. The simulations were based on a solution to the steady-state equation of current continuity in a height-integrated ionospheric current. The simulations demonstrate that a simple hydrodynamical model can account for the narrow 'throats' of strong dayside antisunward convection observed during periods of southward <span class="hlt">interplanetary</span> IMF drift, as well as the sunward convection observed during periods of strongly northward IMF drift.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950047166&hterms=convection+currents&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dconvection%2Bcurrents','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950047166&hterms=convection+currents&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dconvection%2Bcurrents"><span>The Earth's magnetosphere is 165 R(sub E) long: Self-consistent currents, convection, magnetospheric structure, and processes for northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fedder, J. A.; Lyon, J. G.</p> <p>1995-01-01</p> <p>The subject of this paper is a self-consistent, magnetohydrodynamic numerical realization for the Earth's magnetosphere which is in a quasi-steady dynamic equilibrium for a due northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF). Although a few hours of steady northward IMF are required for this asymptotic state to be set up, it should still be of considerable theoretical interest because it constitutes a 'ground state' for the solar wind-magnetosphere interaction. Moreover, particular features of this ground state magnetosphere should be observable even under less extreme solar wind conditions. Certain characteristics of this magnetosphere, namely, NBZ Birkeland currents, four-cell ionospheric convection, a relatively weak cross-polar potential, and a prominent flow boundary layer, are widely expected. Other characteristics, such as no open tail lobes, no Earth-connected <span class="hlt">magnetic</span> flux beyond 155 R(sub E) downstream, <span class="hlt">magnetic</span> merging in a closed topology at the cusps, and a 'tadpole' shaped magnetospheric boundary, might not be expected. In this paper, we will present the evidence for this unusual but interesting magnetospheric equilibrium. We will also discuss our present understanding of this singular state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021486&hterms=origin+mass&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dorigin%2Bmass','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021486&hterms=origin+mass&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dorigin%2Bmass"><span>Origin of coronal mass ejection and <span class="hlt">magnetic</span> cloud: Thermal or <span class="hlt">magnetic</span> driven?</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhang, Gong-Liang; Wang, Chi; He, Shuang-Hua</p> <p>1995-01-01</p> <p>A fundamental problem in Solar-Terrestrial Physics is the origin of the solar transient plasma output, which includes the coronal mass ejection and its <span class="hlt">interplanetary</span> manifestation, e.g. the <span class="hlt">magnetic</span> cloud. The traditional blast wave model resulted from solar thermal pressure impulse has faced with challenge during recent years. In the MHD numerical simulation study of CME, the authors find that the basic feature of the asymmetrical event on 18 August 1980 can be reproduced neither by a thermal pressure nor by a speed increment. Also, the thermal pressure model fails in simulating the <span class="hlt">interplanetary</span> structure with low thermal pressure and strong <span class="hlt">magnetic</span> field strength, representative of a typical <span class="hlt">magnetic</span> cloud. Instead, the numerical simulation results are in favor of the <span class="hlt">magnetic</span> field expansion as the likely mechanism for both the asymmetrical CME event and <span class="hlt">magnetic</span> cloud.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUSMSM21A..01G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUSMSM21A..01G"><span>Plasmapause Boundary Dynamics and the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Effect</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goldstein, J.</p> <p>2006-05-01</p> <p>The plasmapause is the outer boundary of the plasmasphere, the roughly toroidal region of cold, dense, corotating plasma that encircles the Earth and can extend several Earth radii (RE) out into space. The source of plasma in this region is ionospheric outflow (or upflow), which fills plasmaspheric field lines with a mixture of protons, helium ions, and oxygen ions on a timescale of several days. A distinct outer plasmapause boundary forms when plasmaspheric plasma is removed, a process known as erosion. Plasmaspheric erosion occurs most strongly during times of southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF), when magnetospheric convection is greatly enhanced. Decades of theory and observation support the idea that enhanced sunward convection (during southward IMF) forms large plumes of dense plasma that stretch sunward from the main plasmasphere during erosion. The plasmapause during erosion events is distorted: reduced on the nightside, elongated on the dayside, and in general, overlapping the boundaries of regions of warmer plasmas (such as the ring current and radiation belts) that experience increased loss rates from wave-particle interactions in the overlap regions. Thus, the plasmapause boundary is of critical importance to the global dynamics of these warmer particles. In recent years, the southward IMF (i.e., convection) effect on the plasmapause has been fairly well characterized, but what has received less attention is the northward IMF effect. What happens at the plasmapause boundary following disturbances, when convection is reduced but ionospheric outflow has not yet had enough time to refill the plasmaspheric flux tubes? Observations by CRRES, Polar, IMAGE, Cluster, and other spacecraft have shown a bewildering variety of fine-scale plasmapause density structure during recovery and deep quiet phases. Many plasmapause features have been classified, sorted and named, but nonetheless, remain unexplained. This paper will present our current understanding</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790041801&hterms=wind+monitor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dwind%2Bmonitor','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790041801&hterms=wind+monitor&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dwind%2Bmonitor"><span>Signatures of solar wind latitudinal structure in <span class="hlt">interplanetary</span> Lyman-alpha emissions - Mariner 10 observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kumar, S.; Broadfoot, A. L.</p> <p>1979-01-01</p> <p>A detailed analysis is conducted which shows that signatures in the <span class="hlt">interplanetary</span> Lyman-alpha emissions observed in three different data sets from Mariner 10 (corresponding to different locations of the spacecraft) provide firm evidence that the intensity departures are correlated with a decrease in solar wind flux with increasing latitude. It is suggested that observations of the <span class="hlt">interplanetary</span> emission can be used to monitor <span class="hlt">average</span> solar wind activity at high latitudes. The asymmetry in the solar radiation field as a source of observed departures in L-alpha data is considered and attention is given to the interstellar hydrogen and helium density.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21578263-magnetic-field-line-lengths-interplanetary-coronal-mass-ejections-inferred-from-energetic-electron-events','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21578263-magnetic-field-line-lengths-interplanetary-coronal-mass-ejections-inferred-from-energetic-electron-events"><span><span class="hlt">MAGNETIC</span> FIELD-LINE LENGTHS IN <span class="hlt">INTERPLANETARY</span> CORONAL MASS EJECTIONS INFERRED FROM ENERGETIC ELECTRON EVENTS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kahler, S. W.; Haggerty, D. K.; Richardson, I. G., E-mail: AFRL.RVB.PA@hanscom.af.mil</p> <p></p> <p>About one quarter of the observed <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) are characterized by enhanced <span class="hlt">magnetic</span> fields that smoothly rotate in direction over timescales of about 10-50 hr. These ICMEs have the appearance of <span class="hlt">magnetic</span> flux ropes and are known as '<span class="hlt">magnetic</span> clouds' (MCs). The total lengths of MC field lines can be determined using solar energetic particles of known speeds when the solar release times and the 1 AU onset times of the particles are known. A recent examination of about 30 near-relativistic (NR) electron events in and near 8 MCs showed no obvious indication that the field-line lengthsmore » were longest near the MC boundaries and shortest at the MC axes or outside the MCs, contrary to the expectations for a flux rope. Here we use the impulsive beamed NR electron events observed with the Electron Proton and Alpha Monitor instrument on the Advanced Composition Explorer spacecraft and type III radio bursts observed on the Wind spacecraft to determine the field-line lengths inside ICMEs included in the catalog of Richardson and Cane. In particular, we extend this technique to ICMEs that are not MCs and compare the field-line lengths inside MCs and non-MC ICMEs with those in the ambient solar wind outside the ICMEs. No significant differences of field-line lengths are found among MCs, ICMEs, and the ambient solar wind. The estimated number of ICME field-line turns is generally smaller than those deduced for flux-rope model fits to MCs. We also find cases in which the electron injections occur in solar active regions (ARs) distant from the source ARs of the ICMEs, supporting CME models that require extensive coronal <span class="hlt">magnetic</span> reconnection with surrounding fields. The field-line lengths are found to be statistically longer for the NR electron events classified as ramps and interpreted as shock injections somewhat delayed from the type III bursts. The path lengths of the remaining spike and pulse electron events are compared with model</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110023536&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwhite%2Bcane','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110023536&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwhite%2Bcane"><span><span class="hlt">Magnetic</span> Field-Line Lengths in <span class="hlt">Interplanetary</span> Coronal Mass Ejections Inferred from Energetic Electron Events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kahler, S. W.; Haggerty, D. K.; Richardson, I. G.</p> <p>2011-01-01</p> <p>About one quarter of the observed <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) are characterized by enhanced <span class="hlt">magnetic</span> fields that smoothly rotate in direction over timescales of about 10-50 hr. These ICMEs have the appearance of <span class="hlt">magnetic</span> flux ropes and are known as "<span class="hlt">magnetic</span> clouds" (MCs). The total lengths of MC field lines can be determined using solar energetic particles of known speeds when the solar release times and the I AU onset times of the particles are known. A recent examination of about 30 near-relativistic (NR) electron events in and near 8 MCs showed no obvious indication that the field-line lengths were longest near the MC boundaries and shortest at the MC axes or outside the MCs, contrary to the expectations for a flux rope. Here we use the impulsive beamed NR electron events observed with the Electron Proton and Alpha Monitor instrument on the Advanced Composition Explorer spacecraft and type III radio bursts observed on the Wind spacecraft to determine the field-line lengths inside ICMEs included in the catalog of Richardson & Cane. In particular, we extend this technique to ICMEs that are not MCs and compare the field-line lengths inside MCs and non-MC ICMEs with those in the ambient solar wind outside the ICMEs. No significant differences of field-line lengths are found among MCs, ICMEs, and the ambient solar wind. The estimated number of ICME field-line turns is generally smaller than those deduced for flux-rope model fits to MCs. We also find cases in which the electron injections occur in solar active regions CARs) distant from the source ARs of the ICMEs, supporting CME models that require extensive coronal <span class="hlt">magnetic</span> reconnection with surrounding fields. The field-line lengths are found to be statistically longer for the NR electron events classified as ramps and interpreted as shock injections somewhat delayed from the type III bursts. The path lengths of the remaining spike and pulse electron events are compared with model calculations of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22663622-sunward-propagating-solar-energetic-electrons-inside-multiple-interplanetary-flux-ropes','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22663622-sunward-propagating-solar-energetic-electrons-inside-multiple-interplanetary-flux-ropes"><span>Sunward-propagating Solar Energetic Electrons inside Multiple <span class="hlt">Interplanetary</span> Flux Ropes</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Gómez-Herrero, Raúl; Hidalgo, Miguel A.; Carcaboso, Fernando</p> <p>2017-05-10</p> <p>On 2013 December 2 and 3, the SEPT and STE instruments on board STEREO-A observed two solar energetic electron events with unusual sunward-directed fluxes. Both events occurred during a time interval showing typical signatures of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs). The electron timing and anisotropies, combined with extreme-ultraviolet solar imaging and radio wave spectral observations, are used to confirm the solar origin and the injection times of the energetic electrons. The solar source of the ICME is investigated using remote-sensing observations and a three-dimensional reconstruction technique. In situ plasma and <span class="hlt">magnetic</span> field data combined with energetic electron observations and amore » flux-rope model are used to determine the ICME <span class="hlt">magnetic</span> topology and the <span class="hlt">interplanetary</span> electron propagation path from the Sun to 1 au. Two consecutive flux ropes crossed the STEREO-A location and each electron event occurred inside a different flux rope. In both cases, the electrons traveled from the solar source to 1 au along the longest legs of the flux ropes still connected to the Sun. During the December 2 event, energetic electrons propagated along the <span class="hlt">magnetic</span> field, while during the December 3 event they were propagating against the field. As found by previous studies, the energetic electron propagation times are consistent with a low number of field line rotations N < 5 of the flux rope between the Sun and 1 au. The flux rope model used in this work suggests an even lower number of rotations.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSM11B2303L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSM11B2303L"><span>Electron Dropout Echoes Induced by <span class="hlt">Interplanetary</span> Shock: A Statistical Study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Z.; Zong, Q.; Hao, Y.; Zhou, X.; Ma, X.; Liu, Y.</p> <p>2017-12-01</p> <p>"Electron dropout echo" as indicated by repeated moderate dropout and recovery signatures of the flux of energetic electron in the out radiation belt region has been investigated systematically. The electron dropout and its echoes are usually found for higher energy (> 300 keV) channels fluxes, whereas the flux enhancements are obvious for lower energy electrons simultaneously after the <span class="hlt">interplanetary</span> shock arrives at the Earth's geosynchronous orbit. 104 dropout echo events have been found from 215 <span class="hlt">interplanetary</span> shock events from 1998 to 2007 based on LANL satellite data. In analogy to substorm injections, these 104 events could be naturally divided into two categories: dispersionless (49 events) or dispersive (55 events) according to the energy dispersion of the initial dropout. It is found that locations of dispersionless events are distributed mainly in the duskside magnetosphere. Further, the obtained locations derived from dispersive events with the time-of-flight technique of the initial dropout regions are mainly located at the duskside as well. Statistical studies have shown that the effect of shock normal, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field Bz and solar wind dynamic pressure may be insignificant to these electron dropout events. We suggest that the electric field impulse induced by the IP shock produces a more pronounced inward migration of electrons at the dusk side, resulting in the observed dusk-side moderate dropout of electron flux and its consequent echoes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950046221&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DOpen%2BField','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950046221&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DOpen%2BField"><span><span class="hlt">Interplanetary</span> <span class="hlt">magnetic</span> field control of mantle precipitation and associated field-aligned currents</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Xu, Dingan; Kivelson, Margaret G.; Walker, Ray J.; Newell, Patrick T.; Meng, C.-I.</p> <p>1995-01-01</p> <p>Dayside reconnection, which is particularly effective for a southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF), allows magnetosheath particles to enter the magnetosphere where they form the plasma mantle. The motions of the reconnected flux tube produce convective flows in the ionosphere. It is known that the convection patterns in the polar cap are skewed to the dawnside for a positive IMF B(sub y) (or duskside for a negative IMF B(sub y)) in the northern polar cap. Correspondingly, one would expect to find asymmetric distributions of mantle particle precipitation, but previous results have been unclear. In this paper the correlation between B(sub y) and the distribution of mantle particle precipitation is studied for steady IMF conditions with southward IMF. Ion and electron data from the Defense Meteorological Satellite Program (DMSP) F6 and F7 satellites are used to identify the mantle region and IMP 8 is used as a solar wind monitor to characterize the IMF. We study the local time extension of mantle precipitation in the prenoon and postnoon regions. We find that, in accordance with theoretical expectations for a positive (negative) IMF B(sub y), mantle particle precipitation mainly appears in the prenoon region of the northern (southern) hemisphere. The mantle particle precipitation can extend to as early as 0600 <span class="hlt">magnetic</span> local time (MLT) in the prenoon region but extends over a smaller local time region in the postnoon sector (we did not find mantle plasma beyond 1600 MLT in our data set although coverage is scant in this area). Magnetometer data from F7 are used to determine whether part of the region 1 current flows on open field lines. We find that at times part of the region 1 sense current extends into the region of mantle particle precipitation, and is therefore on open field lines. In other cases, region 1 currents are absent on open field lines. Most of the observed features can be readily interpreted in terms of the open magnetosphere model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050180487','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050180487"><span>Propagation of <span class="hlt">Interplanetary</span> Disturbances in the Outer Heliosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wang, Chi</p> <p>2005-01-01</p> <p>Contents include the following: 1. We have developed a one-dimensional, spherically symmetric, multi-fluid MHD model that includes solar wind protons and electrons, pickup ions, and interstellar neutral hydrogen. This model advances the existing solar wind models for the outer heliosphere in two important ways: one is that it distinguishes solar wind protons from pickup ions, and the other is that it allows for energy transfer from pickup ions to the solar wind protons. Model results compare favorably with the Voyager 2 observations. 2. 2. Solar wind slowdown and interstellar neutral density. The solar wind in the outer heliosphere is fundamentally different from that in the inner heliosphere since the effects of interstellar neutrals become significant. 3. ICME propagation from the inner to outer heliosphere. Large coronal mass ejections (CMEs) have major effects on the structure of the solar wind and the heliosphere. The plasma and <span class="hlt">magnetic</span> field can be compressed ahead of <span class="hlt">interplanetary</span> CMEs. 4. During the current solar cycle (Cycle 23), several major CMEs associated with solar flares produced large transient shocks which were observed by widely-separated spacecraft such as Wind at Earth and Voyager 2 beyond 60 AU. Using data from these spacecraft, we use the multi-fluid model to investigate shock propagation and interaction in the heliosphere. Specifically, we studied the Bastille Day 2000, April 2001 and Halloween 2003 events. 5. Statistical properties of the solar wind in the outer heliosphere. In a collaboration with L.F. Burlaga of GSFC, it is shown that the basic statistical properties of the solar wind in the outer heliosphere can be well produced by our model. We studied the large-scale heliospheric <span class="hlt">magnetic</span> field strength fluctuations as a function of distance from the Sun during the declining phase of a solar cycle, using our numerical model with observations made at 1 AU during 1995 as input. 6. Radial heliospheric <span class="hlt">magnetic</span> field events. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810040378&hterms=Streaming+Media&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DStreaming%2BMedia','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810040378&hterms=Streaming+Media&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DStreaming%2BMedia"><span>Bi-directional streaming of solar wind electrons greater than 80 eV - ISEE evidence for a closed-field structure within the driver gas of an <span class="hlt">interplanetary</span> shock</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bame, S. J.; Asbridge, J. R.; Feldman, W. C.; Gosling, J. T.; Zwickl, R. D.</p> <p>1981-01-01</p> <p>In near time coincidence with the arrival of helium enriched plasma driving the shock wave disturbance of November 12-13, 1978, strong bi-directional streaming of solar wind electrons greater than about 80 eV was observed with Los Alamos instrumentation on ISEE 3. The streaming persisted for many hours simultaneously parallel and anti-parallel to the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field which was directed roughly perpendicular to the sun-satellite line. This example of bidirectional streaming cannot be explained by field line connection to the earth's bow shock or the outward propagating <span class="hlt">interplanetary</span> shock which passed ISEE 3 approximately 16 hours earlier. The event is explained if the local <span class="hlt">interplanetary</span> field was a part of a <span class="hlt">magnetic</span> bottle rooted at the sun or a disconnected loop propagating outward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930015892','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930015892"><span>Anomalous aspects of magnetosheath flow and of the shape and oscillations of the magnetopause during an interval of strongly northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Chen, Sheng-Hsien; Kivelson, Margaret G.; Gosling, Jack T.; Walker, Raymond T.; Lazarus, Allan J.</p> <p>1992-01-01</p> <p>On 15 Feb. 1978, the orientation of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) remained steadily northward for more than 12 hours. The ISEE 1 and 2 spacecraft were located near apogee on the dawn side flank of the magnetotail. IMP 8 was almost symmetrically located in the magnetosheath on the dusk flank and IMP 7 was upstream in the solar wind. Using plasma and <span class="hlt">magnetic</span> field data, we show the following: (1) the magnetosheath flow speed on the flanks of the magnetotail steadily exceeded the solar wind speed by 20 percent; (2) surface waves with approximately a 5-min period and very non-sinusoidal waveform were persistently present on the dawn magnetopause and waves of similar period were present in the dusk magnetosheath; and (3) the magnetotail ceased to flare at an antisunward distance of 15 R(sub E). We propose that the acceleration of the magnetosheath flow is achieved by <span class="hlt">magnetic</span> tension in the draped field configuration for northward IMF and that the reduction of tail flaring is consistent with a decreased amount of open <span class="hlt">magnetic</span> flux and a larger standoff distance of the subsolar magnetopause. Results of a three-dimensional magnetohydrodynamic simulation support this phenomenological model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790059028&hterms=Wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DWind%2Benergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790059028&hterms=Wind+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DWind%2Benergy"><span>Relationship between the growth of the ring current and the <span class="hlt">interplanetary</span> quantity. [solar wind energy-magnetospheric coupling parameter correlation with substorm AE index</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Akasofu, S.-I.</p> <p>1979-01-01</p> <p>Akasofu (1979) has reported that the <span class="hlt">interplanetary</span> parameter epsilon correlates reasonably well with the magnetospheric substorm index AE; in the first approximation, epsilon represents the solar wind coupled to the magnetosphere. The correlation between the <span class="hlt">interplanetary</span> parameter, the auroral electrojet index and the ring current index is examined for three <span class="hlt">magnetic</span> storms. It is shown that when the <span class="hlt">interplanetary</span> parameter exceeds the amount that can be dissipated by the ionosphere in terms of the Joule heat production, the excess energy is absorbed by the ring current belt, producing an abnormal growth of the ring current index.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRA..120.6218Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.6218Z"><span>A statistical study of the low-altitude ionospheric <span class="hlt">magnetic</span> fields over the north pole of Venus</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, T. L.; Baumjohann, W.; Russell, C. T.; Villarreal, M. N.; Luhmann, J. G.; Teh, W. L.</p> <p>2015-08-01</p> <p>Examination of Venus Express (VEX) low-altitude ionospheric <span class="hlt">magnetic</span> field measurements during solar minimum has revealed the presence of strong <span class="hlt">magnetic</span> fields at low altitudes over the north pole of Venus. A total of 77 events with strong <span class="hlt">magnetic</span> fields as VEX crossed the northern polar region were identified between July 2008 and October 2009. These events all have strong horizontal fields, slowly varying with position. Using the superposed epoch method, we find that the <span class="hlt">averaged</span> peak field is about 45 nT, which is well above the <span class="hlt">average</span> ambient ionospheric field of 20 nT, with a full width at half maximum duration of 32 s, equivalent to a width of about 300 km. Considering the field orientation preference and spacecraft trajectory geometry, we conclude that these strong fields are found over the northern hemisphere with an occurrence frequency of more than 33% during solar minimum. They do not show a preference for any particular <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) orientation. However, they are found over the geographic pole more often when the <span class="hlt">interplanetary</span> field is in the Venus orbital plane than when it is perpendicular to the orbital plane of Venus. The structures were found most frequently in the -E hemisphere, determined from the IMF orientation. The enhanced <span class="hlt">magnetic</span> field is mainly quasi perpendicular to solar wind flow direction, and it is suggested that these structures form in the low-altitude collisional ionosphere where the diffusion and convection times are long.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150018049','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150018049"><span>A Free-Return Earth-Moon Cycler Orbit for an <span class="hlt">Interplanetary</span> Cruise Ship</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Genova, Anthony L.; Aldrin, Buzz</p> <p>2015-01-01</p> <p>A periodic circumlunar orbit is presented that can be used by an <span class="hlt">interplanetary</span> cruise ship for regular travel between Earth and the Moon. This Earth-Moon cycler orbit was revealed by introducing solar gravity and modest phasing maneuvers (<span class="hlt">average</span> of 39 m/s per month) which yields close-Earth encounters every 7 or 10 days. Lunar encounters occur every 26 days and offer the chance for a smaller craft to depart the cycler and enter lunar orbit, or head for a Lagrange point (e.g., EM-L2 halo orbit), distant retrograde orbit (DRO), or <span class="hlt">interplanetary</span> destination such as a near-Earth object (NEO) or Mars. Additionally, return-to-Earth abort options are available from many points along the cycling trajectory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990102891&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dlazarus','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990102891&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dlazarus"><span>Typical and Unusual Properties of <span class="hlt">Magnetic</span> Clouds during the WIND Era</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lepping, R. P.; Berdichevsky, D.; Szabo, A.; Burlaga, L. F.; Thompson, B. J.; Mariani, F.; Lazarus, A. J.; Steinberg, J. T.</p> <p>1999-01-01</p> <p>A list of 33 <span class="hlt">magnetic</span> clouds as identified in WIND <span class="hlt">magnetic</span> field and plasma data has been compiled. The intervals for these events are provided as part of NASA/GSFC, WIND-MFI's Website under the URL http://lepmfi.qsfc.nasa.gov/mfi/mag_cloud publ.html#table The period covered in this study is from early 1995 to November 1998 which primarily occurs in the quiet part of the solar cycle. A force free, cylindrically symmetric, <span class="hlt">magnetic</span> field model has been applied to the field data in 1-hour <span class="hlt">averaged</span> form for all of these events (except one small event where 10 min avg's were used) and the resulting fit-parameters examined. Each event was provided a semi-quantitatively determined quality factor (excellent, good or poor). A set of 28 good or better cases, spanning a surprisingly large range of values for its various properties, was used for further analysis. These properties are, for example, durations, attitudes, sizes, asymmetries, axial field strengths, speeds, and relative impact parameters. They will be displayed and analyzed, along with some related derived quantities, with emphasis on typical vs unusual properties and on the <span class="hlt">magnetic</span> fields <span class="hlt">magnetic</span> clouds' relationships to the Sun and to upstream <span class="hlt">interplanetary</span> shocks, where possible. For example, it is remarkable how narrowly distributed the speeds of these clouds are, and the overall <span class="hlt">average</span> speed (390 techniques km/s) is less than that normally quoted for the <span class="hlt">average</span> solar wind speed (420 km/s) despite the fact that many of these clouds are d"drivers" of <span class="hlt">interplanetary</span> shocks. On <span class="hlt">average</span>, a cloud appears to be a little less symmetric when the spacecraft is able to pass close to the cloud's axis as compared to a farther out passage. The <span class="hlt">average</span> longitude and latitude (in GSE) of the axes of the clouds are 85 degrees and 8 degrees, respectively, with standard deviations near 40 degrees. Also, the half=yearly <span class="hlt">averaged</span> axial <span class="hlt">magnetic</span> flux has approximately tripled. almost monotonically, from about 6 to 17 X 10</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850026461','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850026461"><span>Particle acceleration due to shocks in the <span class="hlt">interplanetary</span> field: High time resolution data and simulation results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kessel, R. L.; Armstrong, T. P.; Nuber, R.; Bandle, J.</p> <p>1985-01-01</p> <p>Data were examined from two experiments aboard the Explorer 50 (IMP 8) spacecraft. The Johns Hopkins University/Applied Lab Charged Particle Measurement Experiment (CPME) provides 10.12 second resolution ion and electron count rates as well as 5.5 minute or longer <span class="hlt">averages</span> of the same, with data sampled in the ecliptic plane. The high time resolution of the data allows for an explicit, point by point, merging of the <span class="hlt">magnetic</span> field and particle data and thus a close examination of the pre- and post-shock conditions and particle fluxes associated with large angle oblique shocks in the <span class="hlt">interplanetary</span> field. A computer simulation has been developed wherein sample particle trajectories, taken from observed fluxes, are allowed to interact with a planar shock either forward or backward in time. One event, the 1974 Day 312 shock, is examined in detail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760053294&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D70%26Ntt%3Dlazarus','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760053294&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D70%26Ntt%3Dlazarus"><span>Suprathermal protons in the <span class="hlt">interplanetary</span> solar wind</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goodrich, C. C.; Lazarus, A. J.</p> <p>1976-01-01</p> <p>Using the Mariner 5 solar wind plasma and <span class="hlt">magnetic</span> field data, we present observations of field-aligned suprathermal proton velocity distributions having pronounced high-energy shoulders. These observations, similar to the interpenetrating stream observations of Feldman et al. (1974), are clear evidence that such proton distributions are <span class="hlt">interplanetary</span> rather than bow shock associated phenomena. Large Alfven speed is found to be a requirement for the occurrence of suprathermal proton distribution; further, we find the proportion of particles in the shoulder to be limited by the magnitude of the Alfven speed. It is suggested that this last result could indicate that the proton thermal anisotropy is limited at times by wave-particle interactions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JASS...28..123M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JASS...28..123M"><span>Variation of <span class="hlt">Magnetic</span> Field (By , Bz) Polarity and Statistical Analysis of Solar Wind Parameters during the <span class="hlt">Magnetic</span> Storm Period</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moon, Ga-Hee</p> <p>2011-06-01</p> <p>It is generally believed that the occurrence of a <span class="hlt">magnetic</span> storm depends upon the solar wind conditions, particularly the southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) component. To understand the relationship between solar wind parameters and <span class="hlt">magnetic</span> storms, variations in <span class="hlt">magnetic</span> field polarity and solar wind parameters during <span class="hlt">magnetic</span> storms are examined. A total of 156 storms during the period of 1997~2003 are used. According to the <span class="hlt">interplanetary</span> driver, <span class="hlt">magnetic</span> storms are divided into three types, which are coronal mass ejection (CME)-driven storms, co-rotating interaction region (CIR)-driven storms, and complicated type storms. Complicated types were not included in this study. For this purpose, the manner in which the direction change of IMF By and Bz components (in geocentric solar magnetospheric coordinate system coordinate) during the main phase is related with the development of the storm is examined. The time-integrated solar wind parameters are compared with the time-integrated disturbance storm time (Dst) index during the main phase of each <span class="hlt">magnetic</span> storm. The time lag with the storm size is also investigated. Some results are worth noting: CME-driven storms, under steady conditions of Bz < 0, represent more than half of the storms in number. That is, it is found that the <span class="hlt">average</span> number of storms for negative sign of IMF Bz (T1~T4) is high, at 56.4%, 53.0%, and 63.7% in each storm category, respectively. However, for the CIR-driven storms, the percentage of moderate storms is only 29.2%, while the number of intense storms is more than half (60.0%) under the Bz < 0 condition. It is found that the correlation is highest between the time-integrated IMF Bz and the time-integrated Dst index for the CME-driven storms. On the other hand, for the CIR-driven storms, a high correlation is found, with the correlation coefficient being 0.93, between time-integrated Dst index and time-integrated solar wind speed, while a low correlation, 0.51, is found between</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19810012468','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19810012468"><span>Fine-scale characteristics of <span class="hlt">interplanetary</span> sector</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Behannon, K. W.; Neubauer, F. M.; Barnstoff, H.</p> <p>1980-01-01</p> <p>The structure of the <span class="hlt">interplanetary</span> sector boundaries observed by Helios 1 within sector transition regions was studied. Such regions consist of intermediate (nonspiral) <span class="hlt">average</span> field orientations in some cases, as well as a number of large angle directional discontinuities (DD's) on the fine scale (time scales 1 hour). Such DD's are found to be more similar to tangential than rotational discontinuities, to be oriented on <span class="hlt">average</span> more nearly perpendicular than parallel to the ecliptic plane to be accompanied usually by a large dip ( 80%) in B and, with a most probable thickness of 3 x 10 to the 4th power km, significantly thicker previously studied. It is hypothesized that the observed structures represent multiple traversals of the global heliospheric current sheet due to local fluctuations in the position of the sheet. There is evidence that such fluctuations are sometimes produced by wavelike motions or surface corrugations of scale length 0.05 - 0.1 AU superimposed on the large scale structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH31D..07H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH31D..07H"><span>Multi-spacecraft Observations of the Coronal and <span class="hlt">Interplanetary</span> Evolution of a Solar Eruption Associated with Two Active Regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hu, H.; Liu, Y. D.; Wang, R.; Zhao, X.; Zhu, B.; Yang, Z.</p> <p>2017-12-01</p> <p>We investigate the coronal and <span class="hlt">interplanetary</span> evolution of a coronal mass ejection (CME) launched on 2010 September 4 from a source region linking two active regions (ARs), 11101 and 11103, using extreme ultraviolet imaging, magnetogram, white-light, and in situ observations from SDO, STEREO, SOHO, VEX, and Wind. A potential-field source-surface model is employed to examine the configuration of the coronal <span class="hlt">magnetic</span> field surrounding the source region. The graduated cylindrical shell model and a triangulation method are applied to determine the kinematics of the CME in the corona and <span class="hlt">interplanetary</span> space. From the remote sensing and in situ observations, we obtain some key results: (1) the CME was deflected in both the eastward and southward directions in the low corona by the <span class="hlt">magnetic</span> pressure from the two ARs, and possibly interacted with another ejection, which caused that the CME arrived at VEX that was longitudinally distant from the source region; (2) although VEX was closer to the Sun, the observed and derived CME arrival times at VEX are not earlier than those at Wind, which suggests the importance of determining both the frontal shape and propagation direction of the CME in <span class="hlt">interplanetary</span> space; and (3) the ICME was compressed in the radial direction while the longitudinal transverse size was extended.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017RScI...88j3507K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017RScI...88j3507K"><span>Ring-<span class="hlt">averaged</span> ion velocity distribution function probe for laboratory <span class="hlt">magnetized</span> plasma experiment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kawamori, Eiichirou; Chen, Jinting; Lin, Chiahsuan; Lee, Zongmau</p> <p>2017-10-01</p> <p>Ring-<span class="hlt">averaged</span> velocity distribution function of ions at a fixed guiding center position is a fundamental quantity in the gyrokinetic plasma physics. We have developed a diagnostic tool for the ring <span class="hlt">averaged</span> velocity distribution function of ions for laboratory plasma experiments, which is named as the ring-<span class="hlt">averaged</span> ion distribution function probe (RIDFP). The RIDFP is a set of ion collectors for different velocities. It is designed to be immersed in <span class="hlt">magnetized</span> plasmas and achieves momentum selection of incoming ions by the selection of the ion Larmor radii. To nullify the influence of the sheath potential surrounding the RIDFP on the orbits of the incoming ions, the electrostatic potential of the RIDFP body is automatically adjusted to coincide with the space potential of the target plasma with the use of an emissive probe and a voltage follower. The developed RIDFP successfully measured the equilibrium ring-<span class="hlt">averaged</span> velocity distribution function of a laboratory <span class="hlt">magnetized</span> plasma, which was in accordance with the Maxwellian distribution having an ion temperature of 0.2 eV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29092513','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29092513"><span>Ring-<span class="hlt">averaged</span> ion velocity distribution function probe for laboratory <span class="hlt">magnetized</span> plasma experiment.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kawamori, Eiichirou; Chen, Jinting; Lin, Chiahsuan; Lee, Zongmau</p> <p>2017-10-01</p> <p>Ring-<span class="hlt">averaged</span> velocity distribution function of ions at a fixed guiding center position is a fundamental quantity in the gyrokinetic plasma physics. We have developed a diagnostic tool for the ring <span class="hlt">averaged</span> velocity distribution function of ions for laboratory plasma experiments, which is named as the ring-<span class="hlt">averaged</span> ion distribution function probe (RIDFP). The RIDFP is a set of ion collectors for different velocities. It is designed to be immersed in <span class="hlt">magnetized</span> plasmas and achieves momentum selection of incoming ions by the selection of the ion Larmor radii. To nullify the influence of the sheath potential surrounding the RIDFP on the orbits of the incoming ions, the electrostatic potential of the RIDFP body is automatically adjusted to coincide with the space potential of the target plasma with the use of an emissive probe and a voltage follower. The developed RIDFP successfully measured the equilibrium ring-<span class="hlt">averaged</span> velocity distribution function of a laboratory <span class="hlt">magnetized</span> plasma, which was in accordance with the Maxwellian distribution having an ion temperature of 0.2 eV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20080025046&hterms=electric+transport&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Delectric%2Btransport','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20080025046&hterms=electric+transport&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Delectric%2Btransport"><span>Global Dayside Ionospheric Uplift and Enhancement Associated with <span class="hlt">Interplanetary</span> Electric Fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tsurutani, Bruce; Mannucci, Anthony; Iijima, Byron; Abdu, Mangalathayil Ali; Sobral, Jose Humberto A.; Gonzalez, Walter; Guarnieri, Fernando; Tsuda, Toshitaka; Saito, Akinori; Yumoto, Kiyohumi; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20080025046'); toggleEditAbsImage('author_20080025046_show'); toggleEditAbsImage('author_20080025046_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20080025046_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20080025046_hide"></p> <p>2004-01-01</p> <p>The <span class="hlt">interplanetary</span> shock/electric field event of 5-6 November 2001 is analyzed using ACE <span class="hlt">interplanetary</span> data. The consequential ionospheric effects are studied using GPS receiver data from the CHAMP and SAC-C satellites and altimeter data from the TOPEX/ Poseidon satellite. Data from 100 ground-based GPS receivers as well as Brazilian Digisonde and Pacific sector magnetometer data are also used. The dawn-to-dusk <span class="hlt">interplanetary</span> electric field was initially 33 mV/m just after the forward shock (IMF BZ = -48 nT) and later reached a peak value of 54 mV/m 1 hour and 40 min later (BZ = -78 nT). The electric field was 45 mV/m (BZ = -65 nT) 2 hours after the shock. This electric field generated a <span class="hlt">magnetic</span> storm of intensity DST = -275 nT. The dayside satellite GPS receiver data plus ground-based GPS data indicate that the entire equatorial and midlatitude (up to +/-50(deg) <span class="hlt">magnetic</span> latitude (MLAT)) dayside ionosphere was uplifted, significantly increasing the electron content (and densities) at altitudes greater than 430 km (CHAMP orbital altitude). This uplift peaked 2 1/2 hours after the shock passage. The effect of the uplift on the ionospheric total electron content (TEC) lasted for 4 to 5 hours. Our hypothesis is that the <span class="hlt">interplanetary</span> electric field ''promptly penetrated'' to the ionosphere, and the dayside plasma was convected (by E x B) to higher altitudes. Plasma upward transport/convergence led to a 55-60% increase in equatorial ionospheric TEC to values above 430 km (at 1930 LT). This transport/convergence plus photoionization of atmospheric neutrals at lower altitudes caused a 21% TEC increase in equatorial ionospheric TEC at 1400 LT (from ground-based measurements). During the intense electric field interval, there was a sharp plasma ''shoulder'' detected at midlatitudes by the GPS receiver and altimeter satellites. This shoulder moves equatorward from -54(deg) to -37(deg) MLAT during the development of the main phase of the <span class="hlt">magnetic</span> storm. We presume this to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730013938','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730013938"><span>Alfven waves in spiral <span class="hlt">interplanetary</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Whang, Y. C.</p> <p>1973-01-01</p> <p>A theoretical study is presented of the Alfven waves in the spiral <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. The Alfven waves under consideration are arbitrary, large amplitude, non-monochromatic, microscale waves of any polarization. They superpose on a mesoscale background flow of thermally anisotropic plasma. Using WKB approximation, an analytical solution for the amplitude vectors is obtained as a function of the background flow properties: density, velocity, Alfven speed, thermal anisotropy, and the spiral angel. The necessary condition for the validity of the WKB solution is discussed. The intensity of fluctuations is calculated as a function of heliocentric distance. Relative intensity of fluctuations as compared with the magnitude of the background field has its maximum in the region near l au. Thus outside of this region, the solar wind is less turbulent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060033201&hterms=internet&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dinternet','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060033201&hterms=internet&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dinternet"><span>The <span class="hlt">interplanetary</span> Internet</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hooke, A. J.</p> <p>2000-01-01</p> <p>Architectural design of the <span class="hlt">interplanetary</span> internet is now underway and prototype flight testing of some of the candidate protocols is anticipated within a year. This talk will describe the current status of the project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880059429&hterms=Magnetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DMagnetic%2Benergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880059429&hterms=Magnetic+energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DMagnetic%2Benergy"><span>Influence of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field orientation on polar cap ion trajectories - Energy gain and drift effects</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Delcourt, D. C.; Horwitz, J. L.; Swinney, K. R.</p> <p>1988-01-01</p> <p>The influence of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) orientation on the transport of low-energy ions injected from the ionosphere is investigated using three-dimensional particle codes. It is shown that, unlike the auroral zone outflow, the ions originating from the polar cap region exhibit drastically different drift paths during southward and northward IMF. During southward IMF orientation, a 'two-cell' convection pattern prevails in the ionosphere, and three-dimensional simulations of ion trajectories indicate a preferential trapping of the light ions H(+) in the central plasma sheet, due to the wide azimuthal dispersion of the heavy ions, O(+). In contrast, for northward IMF orientation, the 'four-cell' potential distribution predicted in the ionosphere imposes a temporary ion drift toward higher L shells in the central polar cap. In this case, while the light ions can escape into the magnetotail, the heavy ions can remain trapped, featuring more intense acceleration (from a few electron volts up to the keV range) followed by precipitation at high invariant latitudes, as a consequence of their further travel into the tail.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JASS...34..237K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JASS...34..237K"><span>Characteristics and Geoeffectiveness of Small-scale <span class="hlt">Magnetic</span> Flux Ropes in the Solar Wind</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, Myeong Joon; Park, Kyung Sun; Lee, Dae-Young; Choi, Cheong-Rim; Kim, Rok Soon; Cho, Kyungsuk; Choi, Kyu-Cheol; Kim, Jaehun</p> <p>2017-12-01</p> <p><span class="hlt">Magnetic</span> flux ropes, often observed during intervals of <span class="hlt">interplanetary</span> coronal mass ejections, have long been recognized to be critical in space weather. In this work, we focus on <span class="hlt">magnetic</span> flux rope structure but on a much smaller scale, and not necessarily related to <span class="hlt">interplanetary</span> coronal mass ejections. Using near-Earth solar wind advanced composition explorer (ACE) observations from 1998 to 2016, we identified a total of 309 small-scale <span class="hlt">magnetic</span> flux ropes (SMFRs). We compared the characteristics of identified SMFR events with those of normal <span class="hlt">magnetic</span> cloud (MC) events available from the existing literature. First, most of the MCs and SMFRs have similar values of accompanying solar wind speed and proton densities. However, the <span class="hlt">average</span> <span class="hlt">magnetic</span> field intensity of SMFRs is weaker ( 7.4 nT) than that of MCs ( 10.6 nT). Also, the <span class="hlt">average</span> duration time and expansion speed of SMFRs are 2.5 hr and 2.6 km/s, respectively, both of which are smaller by a factor of 10 than those of MCs. In addition, we examined the geoeffectiveness of SMFR events by checking their correlation with <span class="hlt">magnetic</span> storms and substorms. Based on the criteria Sym-H < -50 nT (for identification of storm occurrence) and AL < -200 nT (for identification of substorm occurrence), we found that for 88 SMFR events (corresponding to 28.5 % of the total SMFR events), substorms occurred after the impact of SMFRs, implying a possible triggering of substorms by SMFRs. In contrast, we found only two SMFRs that triggered storms. We emphasize that, based on a much larger database than used in previous studies, all these previously known features are now firmly confirmed by the current work. Accordingly, the results emphasize the significance of SMFRs from the viewpoint of possible triggering of substorms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750016564','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750016564"><span>A New Look at Jupiter: Results at the Now Frontier. [Pioneer 10, <span class="hlt">interplanetary</span> space, and Jupiter atmosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1975-01-01</p> <p>Pioneer 10's encounter with Jupiter is discussed along with the <span class="hlt">interplanetary</span> space beyond the orbit of Mars. Other topics discussed include the size of Jupiter, the Galilean satellites, the <span class="hlt">magnetic</span> field of Jupiter, radiation belts, Jupiter's weather and interior, and future exploration possibilities. Educational projects are also included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EOSTr..93R..40S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EOSTr..93R..40S"><span>Validating a <span class="hlt">magnetic</span> reconnection model for the magnetopause</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schultz, Colin</p> <p>2012-01-01</p> <p>Originating in the Sun's million-degree corona, the solar wind flows at supersonic speeds into <span class="hlt">interplanetary</span> space, carrying with it the solar <span class="hlt">magnetic</span> field. As the solar wind reaches Earth's orbit, its interaction with the geomagnetic field forms the magnetosphere, a bubble-like structure within the solar wind flow that shields Earth from direct exposure to the solar wind as well as to the highly energetic charged particles produced during solar storms. Under certain orientations, the <span class="hlt">magnetic</span> field entrained in the solar wind, known as the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF), merges with the geomagnetic field, transferring mass, momentum, and energy to the magnetosphere. The merging of these two distinct <span class="hlt">magnetic</span> fields occurs through <span class="hlt">magnetic</span> reconnection, a fundamental plasma-physical process that converts <span class="hlt">magnetic</span> energy into kinetic energy and heat.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH51A2478G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH51A2478G"><span>Ion Ramp Structure of Bow shocks and <span class="hlt">Interplanetary</span> Shocks: Differences and Similarities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goncharov, O.; Safrankova, J.; Nemecek, Z.; Koval, A.; Szabo, A.; Prech, L.; Zastenker, G. N.; Riazantseva, M.</p> <p>2017-12-01</p> <p>Collisionless shocks play a significant role in the solar wind interaction with the Earth. Fast forward shocks driven by coronal mass ejections or by interaction of fast and slow solar wind streams can be encountered in the <span class="hlt">interplanetary</span> space, whereas the bow shock is a standing fast reverse shock formed by an interaction of the supersonic solar wind with the Earth <span class="hlt">magnetic</span> field. Both types of shocks are responsible for a transformation of a part of the energy of the directed solar wind motion to plasma heating and to acceleration of reflected particles to high energies. These processes are closely related to the shock front structure. In present paper, we compares the analysis of low-Mach number fast forward <span class="hlt">interplanetary</span> shocks registered in the solar wind by the DSCOVR, WIND, and ACE with observations of bow shock crossings observed by the Cluster, THEMIS, MMS, and Spektr-R spacecraft. An application of the high-time resolution data facilitates further discussion on formation mechanisms of both types of shocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19990102889&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dlazarus','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19990102889&hterms=lazarus&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3Dlazarus"><span>Some Peculiar Properties of <span class="hlt">Magnetic</span> Clouds as Observed by the WIND Spacecraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Berdichevsky, D.; Lepping, R. P.; Szabo, A.; Burlaga, L. F.; Thompson, B. J.; Lazarus, A. J.; Steinburg, J. T.; Mariani, F.</p> <p>1999-01-01</p> <p>We aimed at understanding the common characteristics of <span class="hlt">magnetic</span> clouds, relevant to solar-<span class="hlt">interplanetary</span> connections, but exceptional ones were noted and are stressed here through a short compendium. The study is based on analyses of 28 good or better events (Out of 33 candidates) as identified in WIND <span class="hlt">magnetic</span> field and plasma data. These cloud intervals are provided by WIND-MFI's Website under the URL (http://lepmfi.gsfc.nasa.gov/mfi/mag_cloud_publ.html#table). The period covered is from early 1995 to November 1998. A force free, cylindrically symmetric, <span class="hlt">magnetic</span> field model has been applied to the field data in usually 1-hour <span class="hlt">averaged</span> form for the cloud analyses. Some of the findings are: (1) one small duration event turned out to have an approximately normal size which was due to a distant almost "skimming" passage by the spacecraft; (2) One truly small event was observed, where 10 min <span class="hlt">averages</span> had to be used in the model fitting; it had an excellent model fit and the usual properties of a <span class="hlt">magnetic</span> cloud, except it possessed a small axial <span class="hlt">magnetic</span> flux; (3) One cloud ha a dual axial-field-polarity, in the sense that the "core" had one polarity and the annular region around it had an opposite polarity. This event also satisfied the model and with a ve3ry good chi-squared value. Some others show a hint of this dual polarity; (4) The temporal distribution of occurrence clouds over the 4 years show a dip in 1996; (5) About 50 % of the clouds had upstream shocks; any others had upstream pressure pulses; (6) The overall <span class="hlt">average</span> speed (390 km/s) of the best 28 events is less than the normally quoted for the <span class="hlt">average</span> solar wind speed (420 km/s) The <span class="hlt">average</span> of central cloud speed to the upstream solar wind speed was not much greater than one (1.08), even though many of these clouds were drivers of <span class="hlt">interplanetary</span> shocks. Cloud expansion is partly the reason for the existence of upstream shocks; (7) The cloud axes often (about 50 % of the time) revealed reasonable</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100042593','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100042593"><span>TPS Ablator Technologies for <span class="hlt">Interplanetary</span> Spacecraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Curry, Donald M.</p> <p>2004-01-01</p> <p>This slide presentation reviews the status of Thermal Protection System (TPS) Ablator technologies and the preparation for use in <span class="hlt">interplanetary</span> spacecraft. NASA does not have adequate TPS ablatives and sufficient selection for planned missions. It includes a comparison of shuttle and <span class="hlt">interplanetary</span> TPS requirements, the status of mainline TPS charring ablator materials, a summary of JSC SBIR accomplishments in developing advanced charring ablators and the benefits of SBIR Ablator/fabrication technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22663626-multi-spacecraft-observations-coronal-interplanetary-evolution-solar-eruption-associated-two-active-regions','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22663626-multi-spacecraft-observations-coronal-interplanetary-evolution-solar-eruption-associated-two-active-regions"><span>Multi-spacecraft Observations of the Coronal and <span class="hlt">Interplanetary</span> Evolution of a Solar Eruption Associated with Two Active Regions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Hu, Huidong; Liu, Ying D.; Wang, Rui</p> <p></p> <p>We investigate the coronal and <span class="hlt">interplanetary</span> evolution of a coronal mass ejection (CME) launched on 2010 September 4 from a source region linking two active regions (ARs), 11101 and 11103, using extreme ultraviolet imaging, magnetogram, white-light, and in situ observations from SDO , STEREO , SOHO , VEX , and Wind . A potential-field source-surface model is employed to examine the configuration of the coronal <span class="hlt">magnetic</span> field surrounding the source region. The graduated cylindrical shell model and a triangulation method are applied to determine the kinematics of the CME in the corona and <span class="hlt">interplanetary</span> space. From the remote sensing andmore » in situ observations, we obtain some key results: (1) the CME was deflected in both the eastward and southward directions in the low corona by the <span class="hlt">magnetic</span> pressure from the two ARs, and possibly interacted with another ejection, which caused that the CME arrived at VEX that was longitudinally distant from the source region; (2) although VEX was closer to the Sun, the observed and derived CME arrival times at VEX are not earlier than those at Wind , which suggests the importance of determining both the frontal shape and propagation direction of the CME in <span class="hlt">interplanetary</span> space; and (3) the ICME was compressed in the radial direction while the longitudinal transverse size was extended.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20090006628&hterms=micro+wind&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmicro%2Bwind','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20090006628&hterms=micro+wind&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmicro%2Bwind"><span>Relationship of <span class="hlt">Interplanetary</span> Shock Micro and Macro Characteristics: A Wind Study</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Szabo, Adam; Koval, A</p> <p>2008-01-01</p> <p>The non-linear least squared MHD fitting technique of Szabo 11 9941 has been recently further refined to provide realistic confidence regions for <span class="hlt">interplanetary</span> shock normal directions and speeds. Analyzing Wind observed <span class="hlt">interplanetary</span> shocks from 1995 to 200 1, macro characteristics such as shock strength, Theta Bn and Mach numbers can be compared to the details of shock micro or kinetic structures. The now commonly available very high time resolution (1 1 or 22 vectors/sec) Wind <span class="hlt">magnetic</span> field data allows the precise characterization of shock kinetic structures, such as the size of the foot, ramp, overshoot and the duration of damped oscillations on either side of the shock. Detailed comparison of the shock micro and macro characteristics will be given. This enables the elucidation of shock kinetic features, relevant for particle energization processes, for observations where high time resolution data is not available. Moreover, establishing a quantitative relationship between the shock micro and macro structures will improve the confidence level of shock fitting techniques during disturbed solar wind conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140006630','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006630"><span>Whistler Waves Associated with Weak <span class="hlt">Interplanetary</span> Shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Velez, J. C. Ramirez; Blanco-Cano, X.; Aguilar-Rodriguez, E.; Russell, C. T.; Kajdic, P.; Jian,, L. K.; Luhmann, J. G.</p> <p>2012-01-01</p> <p>We analyze the properties of 98 weak <span class="hlt">interplanetary</span> shocks measured by the dual STEREO spacecraft over approximately 3 years during the past solar minimum. We study the occurrence of whistler waves associated with these shocks, which on <span class="hlt">average</span> are high beta shocks (0.2 < Beta < 10). We have compared the waves properties upstream and downstream of the shocks. In the upstream region the waves are mainly circularly polarized, and in most of the cases (approx. 75%) they propagate almost parallel to the ambient <span class="hlt">magnetic</span> field (<30 deg.). In contrast, the propagation angle with respect to the shock normal varies in a broad range of values (20 deg. to 90 deg.), suggesting that they are not phase standing. We find that the whistler waves can extend up to 100,000 km in the upstream region but in most cases (88%) are contained in a distance within 30,000 km from the shock. This corresponds to a larger region with upstream whistlers associated with IP shocks than previously reported in the literature. The maximum amplitudes of the waves are observed next to the shock interface, and they decrease as the distance to the shock increases. In most cases the wave propagation direction becomes more aligned with the <span class="hlt">magnetic</span> field as the distance to the shock increases. These two facts suggest that most of the waves in the upstream region are Landau damping as they move away from the shock. From the analysis we also conclude that it is likely that the generation mechanism of the upstream whistler waves is taking place at the shock interface. In the downstream region, the waves are irregularly polarized, and the fluctuations are very compressive; that is, the compressive component of the wave clearly dominates over the transverse one. The majority of waves in the downstream region (95%) propagate at oblique angles with respect to the ambient <span class="hlt">magnetic</span> field (>60 deg.). The wave propagation with respect to the shock-normal direction has no preferred direction and varies similarly to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930020188','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930020188"><span>Long Duration Exposure Facility (LDEF) attitude measurements of the <span class="hlt">Interplanetary</span> Dust Experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kassel, Philip C., Jr.; Motley, William R., III; Singer, S. Fred; Mulholland, J. Derral; Oliver, John P.; Weinberg, Jerry L.; Cooke, William J.; Wortman, Jim J.</p> <p>1993-01-01</p> <p>Analysis of the data from the Long Duration Exposure Facility (LDEF) <span class="hlt">Interplanetary</span> Dust Experiment (IDE) sun sensors has allowed a confirmation of the attitude of LDEF during its first year in orbit. Eight observations of the yaw angle at specific times were made and are tabulated in this paper. These values range from 4.3 to 12.4 deg with maximum uncertainty of plus or minus 2.0 deg and an <span class="hlt">average</span> of 7.9 deg. No specific measurements of pitch or roll were made but the data indicates that LDEF had an <span class="hlt">average</span> pitch down attitude of less than 0.7 deg.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17906941','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17906941"><span>The <span class="hlt">interplanetary</span> exchange of photosynthesis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cockell, Charles S</p> <p>2008-02-01</p> <p>Panspermia, the transfer of organisms from one planet to another, either through <span class="hlt">interplanetary</span> or interstellar space, remains speculation. However, its potential can be experimentally tested. Conceptually, it is island biogeography on an <span class="hlt">interplanetary</span> or interstellar scale. Of special interest is the possibility of the transfer of oxygenic photosynthesis between one planet and another, as it can initiate large scale biospheric productivity. Photosynthetic organisms, which must live near the surface of rocks, can be shown experimentally to be subject to destruction during atmospheric transit. Many of them grow as vegetative cells, which are shown experimentally to be susceptible to destruction by shock during impact ejection, although the effectiveness of this dispersal filter can be shown to be mitigated by the characteristics of the cells and their local environment. Collectively these, and other, experiments reveal the particular barriers to the cross-inoculation of photosynthesis. If oxygen biosignatures are eventually found in the atmospheres of extrasolar planets, understanding the potential for the <span class="hlt">interplanetary</span> exchange of photosynthesis will aid in their interpretation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840058818&hterms=quasi+particle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dquasi%2Bparticle','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840058818&hterms=quasi+particle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dquasi%2Bparticle"><span>Plasma and energetic particle structure upstream of a quasi-parallel <span class="hlt">interplanetary</span> shock</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kennel, C. F.; Scarf, F. L.; Coroniti, F. V.; Russell, C. T.; Wenzel, K.-P.; Sanderson, T. R.; Van Nes, P.; Smith, E. J.; Tsurutani, B. T.; Scudder, J. D.</p> <p>1984-01-01</p> <p>ISEE 1, 2 and 3 data from 1978 on <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields, shock waves and particle energetics are examined to characterize a quasi-parallel shock. The intense shock studied exhibited a 640 km/sec velocity. The data covered 1-147 keV protons and electrons and ions with energies exceeding 30 keV in regions both upstream and downstream of the shock, and also the magnitudes of ion-acoustic and MHD waves. The energetic particles and MHD waves began being detected 5 hr before the shock. Intense halo electron fluxes appeared ahead of the shock. A closed <span class="hlt">magnetic</span> field structure was produced with a front end 700 earth radii from the shock. The energetic protons were cut off from the interior of the <span class="hlt">magnetic</span> bubble, which contained a markedly increased density of 2-6 keV protons as well as the shock itself.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37.2998S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37.2998S"><span>Active shielding for long duration <span class="hlt">interplanetary</span> manned missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Spillantini, Piero</p> <p></p> <p>The problem of protecting astronauts from the cosmic rays action in unavoidable and was therefore preliminary studied by many space agencies. In Europe, in the years 2002-2004, ESA supported two works on this thematic: a topical team in the frame of the ‘life and physical sciences' and a study, assigned by tender, of the ‘radiation exposure and mission strategies for <span class="hlt">interplanetary</span> manned missions to Moon and Mars'. In both studies it was concluded that, while the protection from solar cosmic rays can relay on the use of passive absorbers, for long duration missions the astronauts must be protected from the much more energetic galactic cosmic rays during the whole duration of the mission. This requires the protection of a large habitat where they could live and work, and not a temporary small volume shelter, and the use of active shielding is therefore mandatory. The possibilities offered by using superconducting <span class="hlt">magnets</span> were discussed, and the needed R&D recommended. The technical development occurred in the meantime and the evolution of the panorama of the possible <span class="hlt">interplanetary</span> missions in the near future require to revise these pioneer studies and think of the problem at a scale allowing long human permanence in ‘deep' space, and not for a relatively small number of dedicated astronauts but also for citizens conducting there ‘normal' activities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMMM..394..195S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMMM..394..195S"><span>The effect of stress and incentive <span class="hlt">magnetic</span> field on the <span class="hlt">average</span> volume of <span class="hlt">magnetic</span> Barkhausen jump in iron</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shu, Di; Guo, Lei; Yin, Liang; Chen, Zhaoyang; Chen, Juan; Qi, Xin</p> <p>2015-11-01</p> <p>The <span class="hlt">average</span> volume of <span class="hlt">magnetic</span> Barkhausen jump (AVMBJ) v bar generated by <span class="hlt">magnetic</span> domain wall irreversible displacement under the effect of the incentive <span class="hlt">magnetic</span> field H for ferromagnetic materials and the relationship between irreversible <span class="hlt">magnetic</span> susceptibility χirr and stress σ are adopted in this paper to study the theoretical relationship among AVMBJ v bar(magneto-elasticity noise) and the incentive <span class="hlt">magnetic</span> field H. Then the numerical relationship among AVMBJ v bar, stress σ and the incentive <span class="hlt">magnetic</span> field H is deduced. Utilizing this numerical relationship, the displacement process of <span class="hlt">magnetic</span> domain wall for single crystal is analyzed and the effect of the incentive <span class="hlt">magnetic</span> field H and the stress σ on the AVMBJ v bar (magneto-elasticity noise) is explained from experimental and theoretical perspectives. The saturation velocity of Barkhausen jump characteristic value curve is different when tensile or compressive stress is applied on ferromagnetic materials, because the resistance of <span class="hlt">magnetic</span> domain wall displacement is different. The idea of critical <span class="hlt">magnetic</span> field in the process of <span class="hlt">magnetic</span> domain wall displacement is introduced in this paper, which solves the supersaturated calibration problem of AVMBJ - σ calibration curve.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021482&hterms=Streaming+Media&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DStreaming%2BMedia','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021482&hterms=Streaming+Media&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DStreaming%2BMedia"><span>Bi-directional streaming of halo electrons in <span class="hlt">interplanetary</span> plasma clouds observed between 0.3 and 1 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ivory, K.; Schwenn, R.</p> <p>1995-01-01</p> <p>The solar wind data obtained from the two Helios solar probes in the years 1974 to 1986 were systematically searched for the occurrence of bi-directional electron events. Most often these events are found in conjunction with shock associated <span class="hlt">magnetic</span> clouds. The implications of these observations for the topology of <span class="hlt">interplanetary</span> plasma clouds are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20170009836','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20170009836"><span><span class="hlt">Interplanetary</span> Small Satellite Conference 2017 Program</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dalle, Derek Jordan</p> <p>2017-01-01</p> <p>The <span class="hlt">Interplanetary</span> Small Satellite Conference will be held at San Jose State University on May 1 and 2, 2017. The program attached here contains logistical information for attendees, the agenda, and abstracts of the conference presentations. All abstracts were reviewed by their authors' home institute and approved for public release prior to inclusion in the program booklet. The ISSC explores mission concepts, emerging technologies, and fosters outside the box thinking critical to future <span class="hlt">interplanetary</span> small satellite missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010P%26SS...58.1180P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010P%26SS...58.1180P"><span>Laboratory simulation of <span class="hlt">interplanetary</span> ultraviolet radiation (broad spectrum) and its effects on Deinococcus radiodurans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paulino-Lima, Ivan Gláucio; Pilling, Sérgio; Janot-Pacheco, Eduardo; de Brito, Arnaldo Naves; Barbosa, João Alexandre Ribeiro Gonçalves; Leitão, Alvaro Costa; Lage, Claudia de Alencar Santos</p> <p>2010-08-01</p> <p>The radiation-resistant bacterium Deinococcus radiodurans was exposed to a simulated <span class="hlt">interplanetary</span> UV radiation at the Brazilian Synchrotron Light Laboratory (LNLS). Bacterial samples were irradiated on different substrates to investigate the influence of surface relief on cell survival. The effects of cell multi-layers were also investigated. The ratio of viable microorganisms remained virtually the same (<span class="hlt">average</span> 2%) for integrated doses from 1.2 to 12 kJ m -2, corresponding to 16 h of irradiation at most. The asymptotic profiles of the curves, clearly connected to a shielding effect provided by multi-layering cells on a cavitary substrate (carbon tape), means that the inactivation rate may not change significantly along extended periods of exposure to radiation. Such high survival rates reinforce the possibility of an <span class="hlt">interplanetary</span> transfer of viable microbes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IAUS..327...67P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IAUS..327...67P"><span>Photospheric <span class="hlt">magnetic</span> field of an eroded-by-solar-wind coronal mass ejection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Palacios, J.; Cid, C.; Saiz, E.; Guerrero, A.</p> <p>2017-10-01</p> <p>We have investigated the case of a coronal mass ejection that was eroded by the fast wind of a coronal hole in the <span class="hlt">interplanetary</span> medium. When a solar ejection takes place close to a coronal hole, the flux rope <span class="hlt">magnetic</span> topology of the coronal mass ejection (CME) may become misshapen at 1 AU as a result of the interaction. Detailed analysis of this event reveals erosion of the <span class="hlt">interplanetary</span> coronal mass ejection (ICME) <span class="hlt">magnetic</span> field. In this communication, we study the photospheric <span class="hlt">magnetic</span> roots of the coronal hole and the coronal mass ejection area with HMI/SDO magnetograms to define their <span class="hlt">magnetic</span> characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880001370','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880001370"><span>Plasma-tail activity and the <span class="hlt">interplanetary</span> medium at Halley's Comet during Armada Week: 6-14 March 1986</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Niedner, Malcolm B., Jr.; Schwingenschuh, Konrad; Hoeksema, J. Todd; Dryer, Murray; Mcintosh, Patrick S.</p> <p>1987-01-01</p> <p>The encounters of five spacecraft with Halley's Comet during 6-14 March 1986 offered a unique opportunity to calibrate the solar-wind interaction with cometary plasmas as recorded by remote wide-field and narrow-field/narrowband imaging. Perhaps not generally recognized in the comet community is the additional opportunity offered by the Halley Armada to study the structure of the solar-wind and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) in three dimensions using five sets of data obtained over similar time intervals and heliocentric distances, but at somewhat different heliolatitudes. In fact, the two problems, i.e., comet physics and the structure of the <span class="hlt">interplanetary</span> medium, are coupled if one wants to understand what conditions pertained at the comet between the encounters. This relationship is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19780068596&hterms=1607&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2526%25231607','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19780068596&hterms=1607&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D%2526%25231607"><span>Sources of <span class="hlt">magnetic</span> fields in recurrent <span class="hlt">interplanetary</span> streams</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burlaga, L. F.; Behannon, K. W.; Hansen, S. F.; Pneuman, G. W.; Feldman, W. C.</p> <p>1978-01-01</p> <p>The paper examines sources of <span class="hlt">magnetic</span> fields in recurrent streams observed by the Imp 8 and Heos spacecraft at 1 AU and by Mariner 10 en route to Mercury between October 31, 1973 and February 9, 1974, during Carrington rotations 1607-1610. Although most fields and plasmas at 1 AU were related to coronal holes and the <span class="hlt">magnetic</span> field lines were open in those holes, some of the <span class="hlt">magnetic</span> fields and plasmas at 1 AU were related to open field line regions on the sun which were not associated with known coronal holes, indicating that open field lines may be more basic than coronal holes as sources of the solar wind. <span class="hlt">Magnetic</span> field intensities in five equatorial coronal holes, certain photospheric <span class="hlt">magnetic</span> fields, and the coronal footprints of the sector boundaries on the source surface are characterized.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19780054319&hterms=sparrow&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsparrow','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19780054319&hterms=sparrow&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dsparrow"><span>Zodiacal light as an indicator of <span class="hlt">interplanetary</span> dust</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Weinberg, J. L.; Sparrow, J. G.</p> <p>1978-01-01</p> <p>The most striking feature of the night sky in the tropics is the zodiacal light, which appears as a cone in the west after sunset and in the east before sunrise. It is caused by sunlight scattered or absorbed by particles in the <span class="hlt">interplanetary</span> medium. The zodiacal light is the only source of information about the integrated properties of the whole ensemble of <span class="hlt">interplanetary</span> dust. The brightness and polarization in different directions and at different colors can provide information on the optical properties and spatial distribution of the scattering particles. The zodiacal light arises from two independent physical processes related to the scattering of solar continuum radiation by <span class="hlt">interplanetary</span> dust and to thermal emission which arises from solar radiation that is absorbed by <span class="hlt">interplanetary</span> dust and reemitted mainly at infrared wavelengths. Attention is given to observational parameters of zodiacal light, the methods of observation, errors and absolute calibration, and the observed characteristics of zodiacal light.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22270776-source-regions-interplanetary-magnetic-field-variability-heavy-ion-elemental-composition-gradual-solar-energetic-particle-events','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22270776-source-regions-interplanetary-magnetic-field-variability-heavy-ion-elemental-composition-gradual-solar-energetic-particle-events"><span>SOURCE REGIONS OF THE <span class="hlt">INTERPLANETARY</span> <span class="hlt">MAGNETIC</span> FIELD AND VARIABILITY IN HEAVY-ION ELEMENTAL COMPOSITION IN GRADUAL SOLAR ENERGETIC PARTICLE EVENTS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Ko, Yuan-Kuen; Wang, Yi-Ming; Tylka, Allan J.</p> <p></p> <p>Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. However, an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the potential-field source-surface model to map the Sun-L1 <span class="hlt">interplanetary</span> magneticmore » field (IMF) line back to its source region on the Sun at the time of the SEP observations and (2) then look for a correlation between SEP composition (as measured by Wind and Advanced Composition Explorer at ∼2-30 MeV nucleon{sup –1}) and characteristics of the identified IMF source regions. The study is based on 24 SEP events, identified as a statistically significant increase in ∼20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly emergent solar <span class="hlt">magnetic</span> flux and CMEs was lower than in solar-maximum years, and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF source, with the largest enhancements occurring when the footpoint field is strong due to the nearby presence of an active region (AR). In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering (at least on <span class="hlt">average</span>), similar to that found in impulsive events. Such results lead us to suggest that <span class="hlt">magnetic</span> reconnection in footpoint regions near ARs bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110022647','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110022647"><span>Global Magnetospheric Response to an <span class="hlt">Interplanetary</span> Shock: THEMIS Observations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zhang, Hui; Sibeck, David G.; Zong, Q.-G.; McFadden, James P.; Larson, Davin; Glassmeier, K.-H.; Angelopoulos, V.</p> <p>2011-01-01</p> <p>We investigate the global response of geospace plasma environment to an <span class="hlt">interplanetary</span> shock at approx. 0224 UT on May 28, 2008 from multiple THEMIS spacecraft observations in the magnetosheath (THEMIS B and C) and the mid-afternoon (THEMIS A) and dusk magnetosphere (THEMIS D and E). The interaction of the transmitted <span class="hlt">interplanetary</span> shock with the magnetosphere has global effects. Consequently, it can affect geospace plasma significantly. After interacting with the bow shock, the <span class="hlt">interplanetary</span> shock transmitted a fast shock and a discontinuity which propagated through the magnetosheath toward the Earth at speeds of 300 km/s and 137 km/s respectively. THEMIS A observations indicate that the plasmaspheric plume changed significantly by the <span class="hlt">interplanetary</span> shock impact. The plasmaspheric plume density increased rapidly from 10 to 100/ cubic cm in 4 min and the ion distribution changed from isotropic to strongly anisotropic distribution. Electromagnetic ion cyclotron (EMIC) waves observed by THEMIS A are most likely excited by the anisotropic ion distributions caused by the <span class="hlt">interplanetary</span> shock impact. To our best knowledge, this is the first direct observation of the plasmaspheric plume response to an <span class="hlt">interplanetary</span> shock's impact. THEMIS A, but not D or E, observed a plasmaspheric plume in the dayside magnetosphere. Multiple spacecraft observations indicate that the dawn-side edge of the plasmaspheric plume was located between THEMIS A and D (or E).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000011205&hterms=driverless&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Ddriverless','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000011205&hterms=driverless&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Ddriverless"><span>"Driverless" Shocks in the <span class="hlt">Interplanetary</span> Medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, N.; Kaiser, M. L.; Lara, A.</p> <p>1999-01-01</p> <p>Many <span class="hlt">interplanetary</span> shocks have been detected without an obvious driver behind them. These shocks have been thought to be either blast waves from solar flares or shocks due to sudden increase in solar wind speed caused by interactions between large scale open and closed field lines of the Sun. We investigated this problem using a set of <span class="hlt">interplanetary</span> shock detected {\\it in situ} by the Wind space craft and tracing their solar origins using low frequency radio data obtained by the Wind/WAVES experiment. For each of these "driverless shocks" we could find a unique coronal mass ejections (CME) event observed by the SOHO (Solar and Heliospheric Observatory) coronagraphs. We also found that these CMEs were ejected at large angles from the Sun-Earth line. It appears that the "driverless shocks" are actually driver shocks, but the drivers were not intercepted by the spacecraft. We conclude that the <span class="hlt">interplanetary</span> shocks are much more extended than the driving CMEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020087567&hterms=mass+fraction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmass%2Bfraction','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020087567&hterms=mass+fraction&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dmass%2Bfraction"><span>Iron Charge Distribution as an Identifier of <span class="hlt">Interplanetary</span> Coronal Mass Ejections</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lepri, S. T.; Zurbuchen, T. H.; Fisk, L. A.; Richardson, I. G.; Cane, H. V.; Gloeckler, G.</p> <p>2001-01-01</p> <p>We present solar wind Fe charge state data measured on the Advanced Composition Explorer (ACE) from early 1998 to the middle of 2000. <span class="hlt">Average</span> Fe charge states in the solar wind are typically around 9 to 11. However, deviations from these <span class="hlt">average</span> charge states occur, including intervals with a large fraction of Fe(sup greater or = 16+) which are consistently associated with <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs). By studying the Fe charge state distribution we are able to extract coronal electron temperatures often exceeding 2 x 10(exp 6) kelvins. We also discuss the temporal trends of these events, indicating the more frequent appearance of periods with high Fe charge states as solar activity increases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950063936&hterms=Magnetic+Flux&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DMagnetic%2BFlux','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950063936&hterms=Magnetic+Flux&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DMagnetic%2BFlux"><span>Forced three-dimensional <span class="hlt">magnetic</span> reconnection due to linkage of <span class="hlt">magnetic</span> flux tubes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Otto, A.</p> <p>1995-01-01</p> <p>During periods of southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) orientation the <span class="hlt">magnetic</span> field geometry at the dayside magnetopause is susceptible to <span class="hlt">magnetic</span> reconnection. It has been suggested that reconnection may occur in a localized manner at several patches on the magnetopause. A major problem with this picture is the interaction of <span class="hlt">magnetic</span> flux ropes which are generated by different reconnection processes. An individual flux rope is bent elbowlike where it intersects the magnetopause and the <span class="hlt">magnetic</span> field changes from magnetospheric to <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field orientation. Multiple patches of reconnection can lead to the formation of interlinked <span class="hlt">magnetic</span> flux tubes. Although the corresponding flux is connected to the IMF the northward and southward connected branches are hooked into each other and cannot develop independently. We have studied this problem in the framework of three-dimensional magnetohydrodynamic simulations. The results indicate that a singular current sheet forms at the interface of two interlinked flux tubes if no resistivity is present in the simulation. This current sheet is strongly tilted compared to the original current sheet. In the presence of resistivity the interaction of the two flux tubes forces a fast reconnection process which generates helically twisted closed magnetospheric flux. This linkage induced reconnection generates a boundary layer with layers of open and closed magnetospheric flux and may account for the brightening of auroral arcs poleward of the boundary between open and closed <span class="hlt">magnetic</span> flux.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20100011347','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20100011347"><span>International Launch Vehicle Selection for <span class="hlt">Interplanetary</span> Travel</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ferrone, Kristine; Nguyen, Lori T.</p> <p>2010-01-01</p> <p>In developing a mission strategy for <span class="hlt">interplanetary</span> travel, the first step is to consider launch capabilities which provide the basis for fundamental parameters of the mission. This investigation focuses on the numerous launch vehicles of various characteristics available and in development internationally with respect to upmass, launch site, payload shroud size, fuel type, cost, and launch frequency. This presentation will describe launch vehicles available and in development worldwide, then carefully detail a selection process for choosing appropriate vehicles for <span class="hlt">interplanetary</span> missions focusing on international collaboration, risk management, and minimization of cost. The vehicles that fit the established criteria will be discussed in detail with emphasis on the specifications and limitations related to <span class="hlt">interplanetary</span> travel. The final menu of options will include recommendations for overall mission design and strategy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JGRA..115.5103Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JGRA..115.5103Y"><span>Identification of prominence ejecta by the proton distribution function and <span class="hlt">magnetic</span> fine structure in <span class="hlt">interplanetary</span> coronal mass ejections in the inner heliosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yao, Shuo; Marsch, Eckart; Tu, Chuan-Yi; Schwenn, Rainer</p> <p>2010-05-01</p> <p>This work presents in situ solar wind observations of three <span class="hlt">magnetic</span> clouds (MCs) that contain cold high-density material when Helios 2 was located at 0.3 AU on 9 May 1979, 0.5 AU on 30 March 1976, and 0.7 AU on 24 December 1978. In the cold high-density regions embedded in the <span class="hlt">interplanetary</span> coronal mass ejections we find (1) that the number density of protons is higher than in other regions inside the <span class="hlt">magnetic</span> cloud, (2) the possible existence of He+, (3) that the thermal velocity distribution functions are more isotropic and appear to be colder than in the other regions of the MC, and the proton temperature is lower than that of the ambient plasma, and (4) that the associated <span class="hlt">magnetic</span> field configuration can for all three MC events be identified as a flux rope. This cold high-density region is located at the polarity inversion line in the center of the bipolar structure of the MC <span class="hlt">magnetic</span> field (consistent with previous solar observation work that found that a prominence lies over the neutral line of the related bipolar solar <span class="hlt">magnetic</span> field). Specifically, for the first <span class="hlt">magnetic</span> cloud event on 8 May 1979, a coronal mass ejection (CME) was related to an eruptive prominence previously reported as a result of the observation of Solwind (P78-1). Therefore, we identify the cold and dense region in the MC as the prominence material. It is the first time that prominence ejecta were identified by both the plasma and <span class="hlt">magnetic</span> field features inside 1 AU, and it is also the first time that the thermal ion velocity distribution functions were used to investigate the microstate of the prominence material. Moreover, from our three cases, we also found that this material tended to fall behind the <span class="hlt">magnetic</span> cloud and become smaller as it propagated farther away from the Sun, which confirms speculations in previous work. Overall, our in situ observations are consistent with three-part CME models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AdSpR..61....1O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AdSpR..61....1O"><span>Geoeffectiveness of <span class="hlt">interplanetary</span> shocks controlled by impact angles: A review</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oliveira, D. M.; Samsonov, A. A.</p> <p>2018-01-01</p> <p>The high variability of the Sun's <span class="hlt">magnetic</span> field is responsible for the generation of perturbations that propagate throughout the heliosphere. Such disturbances often drive <span class="hlt">interplanetary</span> shocks in front of their leading regions. Strong shocks transfer momentum and energy into the solar wind ahead of them which in turn enhance the solar wind interaction with <span class="hlt">magnetic</span> fields in its way. Shocks then eventually strike the Earth's magnetosphere and trigger a myriad of geomagnetic effects observed not only by spacecraft in space, but also by magnetometers on the ground. Recently, it has been revealed that shocks can show different geoeffectiveness depending closely on the angle of impact. Generally, frontal shocks are more geoeffective than inclined shocks, even if the former are comparatively weaker than the latter. This review is focused on results obtained from modeling and experimental efforts in the last 15 years. Some theoretical and observational background are also provided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/6772193-interplanetary-magnetic-field-sub-effects-large-scale-field-aligned-currents-near-local-noon-contributions-from-cusp-part-noncusp-part','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/6772193-interplanetary-magnetic-field-sub-effects-large-scale-field-aligned-currents-near-local-noon-contributions-from-cusp-part-noncusp-part"><span>The <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field B[sub y] effects on large-scale field-aligned currents near local noon: Contributions from cusp part and noncusp part</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Yamauchi, M.; Lundin, R.; Woch, J.</p> <p>1993-04-01</p> <p>latitudinals develop a model to account for the effect of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) B[sub y] component on the dayside field-aligned currents (FACs). As part of the model the FACs are divided into a [open quotes]cusp part[close quotes] and a [open quotes]noncusp part[close quotes]. The authors then propose that the cusp part FACs shift in the longitudinal direction while the noncusplike part FACs shift in both longitudinal and latitudinal directions in response to the y component of the IMF. If combined, it is observed that the noncusp part FAC is found poleward of the cusp part FAC system whenmore » the y component of the IMF is large. These two FAC systems flow in the same direction. They reinforce one another, creating a strong FAC, termed the DPY-FAC. The model also predicts that the polewardmost part of the DPY-FAC flows on closed field lines, even in regions conventionally occupied by the polar cap. Results of the model are successfully compared with particle and <span class="hlt">magnetic</span> field data from Viking missions.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890036898&hterms=Property+Types&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DProperty%2BTypes','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890036898&hterms=Property+Types&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DProperty%2BTypes"><span>Characteristics of <span class="hlt">interplanetary</span> type II radio emission and the relationship to shock and plasma properties</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lengyel-Frey, D.; Stone, R. G.</p> <p>1989-01-01</p> <p>A large sample of type II events is the basis of the present study of the properties of <span class="hlt">interplanetary</span> type II bursts' radio-emission properties. Type II spectra seem to be composed of fundamental and harmonic components of plasma emission, where the intensity of the fundamental component increases relative to the harmonic as the burst evolves with heliocentric distance; burst <span class="hlt">average</span> flux density increases as a power of the associated shock's <span class="hlt">average</span> velocity. Solar wind density structures may have a significant influence on type II bandwidths.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008cosp...37.2948S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008cosp...37.2948S"><span>MESSENGER observations of the response of Mercury's magnetosphere to northward and southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Slavin, James</p> <p></p> <p>M. H. Acũa (2), B. J. Anderson (3), D. N. Baker (4), M. Benna (2), S. A. Boardsen (1), G. n Gloeckler (5), R. E. Gold (3), G. C. Ho (3), H. Korth (3), S. M. Krimigis (3), S. A. Livi (6), R. L. McNutt Jr. (3), J. M. Raines (5), M. Sarantos (1), D. Schriver (7), S. C. Solomon (8), P. Travnicek (9), and T. H. Zurbuchen (5) (1) Heliophysics Science Division, NASA GSFC, Greenbelt, MD 20771, USA, (2) Solar System Exploration Division, NASA GSFC, Greenbelt, MD 20771, USA, (3) The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA, (4) Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA, (5) Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, MI 48109, USA (6) Southwest Research Institute, San Antonio, TX 28510, USA, (7) Institute for Geophysics and Planetary Physics, University of California, Los Angeles, CA 90024, USA, (8) Department of Terrestrial <span class="hlt">Magnetism</span>, Carnegie Institution of Washington, DC 20015, USA, and (9) Institute of Atmospheric Physics, Prague, Czech Republic, 14131 MESSENGER's 14 January 2008 encounter with Mercury has provided new observations of the solar wind interaction with this planet. Here we report initial results concerning this miniature magnetosphere's response to the north-south component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF). This is the component of the IMF that is expected to exert the greatest influence over the structure of the magnetopause and the processes responsible for energy transfer into the magnetosphere. The IMF was northward immediately prior to and following the passage of the MESSENGER spacecraft through this small magnetosphere. However, several-minute episodes of southward IMF were observed in the magnetosheath during the inbound portion of the encounter. Evidence for reconnection at the dayside magnetopause in the form of welldeveloped flux transfer events (FTEs) was observed in the magnetosheath following some of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018NewA...60...22C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018NewA...60...22C"><span>Solar flares associated coronal mass ejection accompanied with DH type II radio burst in relation with <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, geomagnetic storms and cosmic ray intensity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chandra, Harish; Bhatt, Beena</p> <p>2018-04-01</p> <p>In this paper, we have selected 114 flare-CME events accompanied with Deca-hectometric (DH) type II radio burst chosen from 1996 to 2008 (i.e., solar cycle 23). Statistical analyses are performed to examine the relationship of flare-CME events accompanied with DH type II radio burst with <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> field (IMF), Geomagnetic storms (GSs) and Cosmic Ray Intensity (CRI). The collected sample events are divided into two groups. In the first group, we considered 43 events which lie under the CME span and the second group consists of 71 events which are outside the CME span. Our analysis indicates that flare-CME accompanied with DH type II radio burst is inconsistent with CSHKP flare-CME model. We apply the Chree analysis by the superposed epoch method to both set of data to find the geo-effectiveness. We observed different fluctuations in IMF for arising and decay phase of solar cycle in both the cases. Maximum decrease in Dst during arising and decay phase of solar cycle is different for both the cases. It is noted that when flare lie outside the CME span CRI shows comparatively more variation than the flare lie under the CME span. Furthermore, we found that flare lying under the CME span is more geo effective than the flare outside of CME span. We noticed that the time leg between IMF Peak value and GSs, IMF and CRI is on <span class="hlt">average</span> one day for both the cases. Also, the time leg between CRI and GSs is on <span class="hlt">average</span> 0 to 1 day for both the cases. In case flare lie under the CME span we observed high correlation (0.64) between CRI and Dst whereas when flare lie outside the CME span a weak correlation (0.47) exists. Thus, flare position with respect to CME span play a key role for geo-effectiveness of CME.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000JGR...10527289B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000JGR...10527289B"><span><span class="hlt">Interplanetary</span> fast shocks and associated drivers observed through the 23rd solar minimum by Wind over its first 2.5 years</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berdichevsky, Daniel B.; Szabo, Adam; Lepping, Ronald P.; Viñas, Adolfo F.; Mariani, Franco</p> <p>2000-12-01</p> <p>A list of the <span class="hlt">interplanetary</span> shocks observed by Wind from its launch (in Nov 1994) to May 1997 is presented. The magnetohydrodynamic nature of the shocks is investigated, and the associated shock parameters and their uncertainties are accurately computed using two techniques. These are: 1) a combination of the ``preaveraged'' <span class="hlt">magnetic</span>-coplanarity, velocity-coplanarity, and the Abraham-Schrauner-mixed methods, and 2) the Viñas and Scudder [1986] technique for solving the nonlinear least squares Rankine-Hugoniot equations. Within acceptable limits these two techniques generally gave the same results, with some exceptions. The reasons for the exceptions are discussed. The mean strength and rate of occurrence of the shocks appear to correlate with the solar cycle. Both showed a decrease in 1996 coincident with the time of the lowest ultraviolet solar radiance, indicative of solar minimum and the beginning of solar cycle 23. Eighteen shocks appeared to be associated with corotating interaction regions (CIRs). The shock normal distribution showed a mean direction peaking in the ecliptic plane and with a longitude of ~200° (GSE coordinates). Another 16 shocks were determined to be driven by solar transients, including <span class="hlt">magnetic</span> clouds. These had a broader distribution of normal directions than those of the CIR cases with a mean direction close to the Sun-Earth line. Eight shocks of unknown origin had normal orientations far off the ecliptic plane. No shock propagated with longitude φn>=220+/-10°, i.e. against the <span class="hlt">average</span> Parker spiral direction. Examination of the obliquity angle θBn (i.e., between the shock normal and the upstream <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field) for the full set of shocks revealed that about 58% were quasi-perpendicular, and about 32% of the shocks oblique, and the rest quasi-parallel. Small uncertainty in the estimated angle θBn was obtained for about 10 shocks with magnetosonic Mach numbers between 1 and 2.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22964714','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22964714"><span>Occupational exposure assessment of <span class="hlt">magnetic</span> fields generated by induction heating equipment-the role of spatial <span class="hlt">averaging</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kos, Bor; Valič, Blaž; Kotnik, Tadej; Gajšek, Peter</p> <p>2012-10-07</p> <p>Induction heating equipment is a source of strong and nonhomogeneous <span class="hlt">magnetic</span> fields, which can exceed occupational reference levels. We investigated a case of an induction tempering tunnel furnace. Measurements of the emitted <span class="hlt">magnetic</span> flux density (B) were performed during its operation and used to validate a numerical model of the furnace. This model was used to compute the values of B and the induced in situ electric field (E) for 15 different body positions relative to the source. For each body position, the computed B values were used to determine their maximum and <span class="hlt">average</span> values, using six spatial <span class="hlt">averaging</span> schemes (9-285 <span class="hlt">averaging</span> points) and two <span class="hlt">averaging</span> algorithms (arithmetic mean and quadratic mean). Maximum and <span class="hlt">average</span> B values were compared to the ICNIRP reference level, and E values to the ICNIRP basic restriction. Our results show that in nonhomogeneous fields, the maximum B is an overly conservative predictor of overexposure, as it yields many false positives. The <span class="hlt">average</span> B yielded fewer false positives, but as the number of <span class="hlt">averaging</span> points increased, false negatives emerged. The most reliable <span class="hlt">averaging</span> schemes were obtained for <span class="hlt">averaging</span> over the torso with quadratic <span class="hlt">averaging</span>, with no false negatives even for the maximum number of <span class="hlt">averaging</span> points investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AcAau.128..160A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AcAau.128..160A"><span>Aquarius, a reusable water-based <span class="hlt">interplanetary</span> human spaceflight transport</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Adamo, Daniel R.; Logan, James S.</p> <p>2016-11-01</p> <p>Attributes of a reusable <span class="hlt">interplanetary</span> human spaceflight transport are proposed and applied to example transits between the Earth/Moon system and Deimos, the outer moon of Mars. Because the transport is 54% water by mass at an <span class="hlt">interplanetary</span> departure, it is christened Aquarius. In addition to supporting crew hydration/hygiene, water aboard Aquarius serves as propellant and as enhanced crew habitat radiation shielding during <span class="hlt">interplanetary</span> transit. Key infrastructure and technology supporting Aquarius operations include pre-emplaced consumables and subsurface habitat at Deimos with crew radiation shielding equivalent to sea level on Earth, resupply in a selenocentric distant retrograde orbit, and nuclear thermal propulsion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860061040&hterms=Saunders&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D60%26Ntt%3DSaunders%252C%2BM','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860061040&hterms=Saunders&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D60%26Ntt%3DSaunders%252C%2BM"><span>The <span class="hlt">average</span> <span class="hlt">magnetic</span> field draping and consistent plasma properties of the Venus magnetotail</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccomas, D. J.; Spence, H. E.; Russell, C. T.; Saunders, M. A.</p> <p>1986-01-01</p> <p>The detailed <span class="hlt">average</span> draping pattern of the <span class="hlt">magnetic</span> field in the deep Venus magnetotail is examined. The variability of the data ordered by spatial location is studied, and the groundwork is laid for developing a coordinate system which measured locations with respect to the tail structures. The reconstruction of the tail in the presence of flapping using a new technique is shown, and the <span class="hlt">average</span> variations in the field components are examined, including the <span class="hlt">average</span> field vectors, cross-tail current density distribution, and J x B forces as functions of location across the tail. The <span class="hlt">average</span> downtail velocity is derived as a function of distance, and a simple model based on the field variations is defined from which the <span class="hlt">average</span> plasma acceleration is obtained as a function of distance, density, and temperature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900003168','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900003168"><span><span class="hlt">Interplanetary</span> energetic particle observations of the March 1989 events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sarris, E. T.; Krimigis, S. M.</p> <p>1989-01-01</p> <p>The IMP-8 spacecraft placed in an elongated orbit of approximately R(sub E) x R(sub E) orbit around the Earth was the only monitor of the energetic particle environment of the near <span class="hlt">interplanetary</span> space during the period of the solar particle events associated with the Active Region 5395 in March 1989. Measurements of energetic ion and electron intensities were obtained in a series of channels within the energy range: 0.3 to 440 MeV for photons, 0.6 to 52 MeV/nuc for alpha particles, 0.7 to 3.3 MeV/nuc for nuclei with Z greater than or equal to 3, 3 to 9 MeV/nuc with Z greater than or equal to 20, and 0.2 to 2.5 MeV for electrons. The responses of selected energy channels during the period 5 to 23 March 1989 are displayed. It is clearly noted that the most prominent energetic ion intensity enhancements in that time interval were associated with the <span class="hlt">interplanetary</span> shock wave of March 13 (07:42 UT) as well as that of March 8 (17:56 UT), which have distinct particle acceleration signatures. These shock waves play a major role in determining the near Earth energetic ion intensities during the above period by accelerating and modulating the ambient solar energetic particle population, which was already present in high intensities in the <span class="hlt">interplanetary</span> medium due to the superposition of a series of solar flare particle events originating in AR 5395. The differential ion intensities at the lowest energy channel of the CPME experiment, which were associated with the March 13 shock wave, reached the highest level in the life of the IMP-8 spacecraft at this energy. At high energies, the shock associated intensity peak was smaller by less than a factor of 3 than the maxima of solar flare particle intensities from some other major flares, in particular from those with sites well connected to the Earth's <span class="hlt">magnetic</span> flux tubes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123.1969T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123.1969T"><span>Observation and Numerical Simulation of Cavity Mode Oscillations Excited by an <span class="hlt">Interplanetary</span> Shock</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takahashi, Kazue; Lysak, Robert; Vellante, Massimo; Kletzing, Craig A.; Hartinger, Michael D.; Smith, Charles W.</p> <p>2018-03-01</p> <p>Cavity mode oscillations (CMOs) are basic magnetohydrodynamic eigenmodes in the magnetosphere predicted by theory and are expected to occur following the arrival of an <span class="hlt">interplanetary</span> shock. However, observational studies of shock-induced CMOs have been sparse. We present a case study of a dayside ultralow-frequency wave event that exhibited CMO properties. The event occurred immediately following the arrival of an <span class="hlt">interplanetary</span> shock at 0829 UT on 15 August 2015. The shock was observed in the solar wind by the Time History of Events and Macroscale Interactions during Substorms-B and -C spacecraft, and magnetospheric ultralow-frequency waves were observed by multiple spacecraft including the Van Allen Probe-A and Van Allen Probe-B spacecraft, which were located in the dayside plasmasphere at L ˜1.4 and L ˜ 2.4, respectively. Both Van Allen Probes spacecraft detected compressional poloidal mode oscillations at ˜13 mHz (fundamental) and ˜26 mHz (second harmonic). At both frequencies, the azimuthal component of the electric field (Eϕ) lagged behind the compressional component of the <span class="hlt">magnetic</span> field (Bμ) by ˜90°. The frequencies and the Eϕ-Bμ relative phase are in good agreement with the CMOs generated in a dipole magnetohydrodynamic simulation that incorporates a realistic plasma mass density distribution and ionospheric boundary condition. The oscillations were also detected on the ground by the European quasi-Meridional Magnetometer Array, which was located near the <span class="hlt">magnetic</span> field footprints of the Van Allen Probes spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950053481&hterms=swimming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dswimming','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950053481&hterms=swimming&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dswimming"><span>Penetration of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field B(sub y) magnetosheath plasma into the magnetosphere: Implications for the predominant magnetopause merging site</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Newell, Patrick T.; Sibeck, David G.; Meng, Ching-I</p> <p>1995-01-01</p> <p>Magnetosheath plasma peertated into the magnetospere creating the particle cusp, and similarly the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) B(sub y) component penetrates the magnetopause. We reexamine the phenomenology of such penetration to investigate implications for the magnetopause merging site. Three models are popular: (1) the 'antiparallel' model, in which merging occurs where the local <span class="hlt">magnetic</span> shear is largest (usually high <span class="hlt">magnetic</span> latitude); (2) a tilted merging line passing through the subsolar point but extending to very high latitudes; or (3) a tilted merging line passing through the subsolar point in which most merging occurs within a few Earth radii of the equatorial plane and local noon (subsolar merging). It is difficult to distinguish between the first two models, but the third implies some very different predictions. We show that properties of the particle cusp imply that plasma injection into the magnetosphere occurs most often at high <span class="hlt">magnetic</span> latitudes. In particular, we note the following: (1) The altitude of the merging site inferred from midaltitude cusp ion pitch angle dispersion is typically 8-12 R(sub E). (2) The highest ion energy observable when moving poleward through the cusp drops long before the bulk of the cusp plasma is reached, implying that ions are swimming upstream against the sheath flow shortly after merging. (3) Low-energy ions are less able to enter the winter cusp than the summer cusp. (4) The local time behavior of the cusp as a function of B(sub y) and B(sub z) corroborates predictions of the high-latitude merging models. We also reconsider the penetration of the IMF B(sub y) component onto closed dayside field lines. Our approach, in which closed field lines ove to fill in flux voids created by asymmetric magnetopause flux erosion, shows that strich subsolar merging cannot account for the observations.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22408061-orbit-averaged-quantities-classical-hellmann-feynman-theorem-magnetic-flux-enclosed-gyro-motion','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22408061-orbit-averaged-quantities-classical-hellmann-feynman-theorem-magnetic-flux-enclosed-gyro-motion"><span>Orbit-<span class="hlt">averaged</span> quantities, the classical Hellmann-Feynman theorem, and the <span class="hlt">magnetic</span> flux enclosed by gyro-motion</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Perkins, R. J., E-mail: rperkins@pppl.gov; Bellan, P. M.</p> <p></p> <p>Action integrals are often used to <span class="hlt">average</span> a system over fast oscillations and obtain reduced dynamics. It is not surprising, then, that action integrals play a central role in the Hellmann-Feynman theorem of classical mechanics, which furnishes the values of certain quantities <span class="hlt">averaged</span> over one period of rapid oscillation. This paper revisits the classical Hellmann-Feynman theorem, rederiving it in connection to an analogous theorem involving the time-<span class="hlt">averaged</span> evolution of canonical coordinates. We then apply a modified version of the Hellmann-Feynman theorem to obtain a new result: the <span class="hlt">magnetic</span> flux enclosed by one period of gyro-motion of a charged particle inmore » a non-uniform <span class="hlt">magnetic</span> field. These results further demonstrate the utility of the action integral in regards to obtaining orbit-<span class="hlt">averaged</span> quantities and the usefulness of this formalism in characterizing charged particle motion.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880012611','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880012611"><span><span class="hlt">Magnetic</span> field hourly <span class="hlt">averages</span> from the Rome-GSFC experiment aboard Helios 1 and Helio 2</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mariani, F.; Ness, N. F.; Bavassano, B.; Bruno, R.; Buccellato, R.; Burlaga, L. F.; Cantarano, S.; Scearce, C. S.; Terenzi, R.; Villante, U.</p> <p>1987-01-01</p> <p>Plots of all the hourly <span class="hlt">averages</span> computed from the solar <span class="hlt">magnetic</span> field measurements obtained during the mission are given separately for Helios 1 and Helios 2. The magnitude and the direction of the <span class="hlt">averaged</span> field are plotted versus the number of solar rotations as seen from Helios, counted from launch.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011758','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011758"><span>Observations of Electromagnetic Whistler Precursors at Supercritical <span class="hlt">Interplanetary</span> Shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wilson, L. B., III; Koval, A.; Szabo, Adam; Breneman, A.; Cattell, C. A.; Goetz, K.; Kellogg, P. J.; Kersten, K.; Kasper, J. C.; Maruca, B. A.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20120011758'); toggleEditAbsImage('author_20120011758_show'); toggleEditAbsImage('author_20120011758_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20120011758_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20120011758_hide"></p> <p>2012-01-01</p> <p>We present observations of electromagnetic precursor waves, identified as whistler mode waves, at supercritical <span class="hlt">interplanetary</span> shocks using the Wind search coil magnetometer. The precursors propagate obliquely with respect to the local <span class="hlt">magnetic</span> field, shock normal vector, solar wind velocity, and they are not phase standing structures. All are right-hand polarized with respect to the <span class="hlt">magnetic</span> field (spacecraft frame), and all but one are right-hand polarized with respect to the shock normal vector in the normal incidence frame. They have rest frame frequencies f(sub ci) < f much < f(sub ce) and wave numbers 0.02 approx < k rho (sub ce) approx <. 5.0. Particle distributions show signatures of specularly reflected gyrating ions, which may be a source of free energy for the observed modes. In one event, we simultaneously observe perpendicular ion heating and parallel electron acceleration, consistent with wave heating/acceleration due to these waves. Al though the precursors can have delta B/B(sub o) as large as 2, fluxgate magnetometer measurements show relatively laminar shock transitions in three of the four events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730056702&hterms=Wave+Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DWave%2BEnergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730056702&hterms=Wave+Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DWave%2BEnergy"><span>Evidence for confinement of low-energy cosmic rays ahead of <span class="hlt">interplanetary</span> shock waves.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Palmeira, R. A. R.; Allum, F. R.</p> <p>1973-01-01</p> <p>Short-lived (about 15 min), low-energy proton increases associated with the passage of <span class="hlt">interplanetary</span> shock waves have been previously reported. In the present paper, we have examined in a fine time scale (about 1 min) the concurrent particle and <span class="hlt">magnetic</span> field data, taken by detectors on Explorer 34, for four of these events. Our results further support the view that these impulsive events are due to confinement of the solar cosmic-ray particles in the region just ahead (about 1,000,000 km) of the advancing shock front.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFMSH31B1667J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFMSH31B1667J"><span>High time resolution observations of the drivers of Forbush decreases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jordan, A. P.; Spence, H. E.; Blake, J. B.; Mulligan, T. L.; Shaul, D. N.</p> <p>2008-12-01</p> <p>The drivers of Forbush decreases in galactic cosmic ray (GCR) fluxes are thought to be <span class="hlt">magnetic</span> turbulence in the sheath of an <span class="hlt">interplanetary</span> coronal mass ejection (ICME) and the closed <span class="hlt">magnetic</span> field lines in the ICME itself. This model, however, is the result of studies utilizing hourly or longer time <span class="hlt">averaging</span>. Such <span class="hlt">averaging</span> can smooth over important correlations between variabilities in the GCR flux and those in the <span class="hlt">interplanetary</span> medium. To test the validity of the current model of Forbush decreases, we analyze a number of Forbush decreases using high time resolution GCR data from the High Sensitivity Telescope (HIST) on Polar and the Spectrometer for INTEGRAL (SPI). We seek causal correlations between the onset of the decrease and structures in the solar wind plasma and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, as measured concurrently with ACE and/or Wind. We find evidence that planar <span class="hlt">magnetic</span> structures in the sheath preceding the ICME may be a factor in driving the decrease in at least one event.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140009617','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140009617"><span>Turbulence in a Global Magnetohydrodynamic Simulation of the Earth's Magnetosphere during Northward and Southward <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>El-Alaoui, M.; Richard, R. L.; Ashour-Abdalla, M.; Walker, R. J.; Goldstein, M. L.</p> <p>2012-01-01</p> <p>We report the results of MHD simulations of Earth's magnetosphere for idealized steady solar wind plasma and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) conditions. The simulations feature purely northward and southward <span class="hlt">magnetic</span> fields and were designed to study turbulence in the magnetotail plasma sheet. We found that the power spectral densities (PSDs) for both northward and southward IMF had the characteristics of turbulent flow. In both cases, the PSDs showed the three scale ranges expected from theory: the energy-containing scale, the inertial range, and the dissipative range. The results were generally consistent with in-situ observations and theoretical predictions. While the two cases studied, northward and southward IMF, had some similar characteristics, there were significant differences as well. For southward IMF, localized reconnection was the main energy source for the turbulence. For northward IMF, remnant reconnection contributed to driving the turbulence. Boundary waves may also have contributed. In both cases, the PSD slopes had spatial distributions in the dissipative range that reflected the pattern of resistive dissipation. For southward IMF there was a trend toward steeper slopes in the dissipative range with distance down the tail. For northward IMF there was a marked dusk-dawn asymmetry with steeper slopes on the dusk side of the tail. The inertial scale PSDs had a dusk-dawn symmetry during the northward IMF interval with steeper slopes on the dawn side. This asymmetry was not found in the distribution of inertial range slopes for southward IMF. The inertial range PSD slopes were clustered around values close to the theoretical expectation for both northward and southward IMF. In the dissipative range, however, the slopes were broadly distributed and the median values were significantly different, consistent with a different distribution of resistivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150008672&hterms=celestial+navigation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dcelestial%2Bnavigation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150008672&hterms=celestial+navigation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dcelestial%2Bnavigation"><span>Mars Science Laboratory <span class="hlt">Interplanetary</span> Navigation Performance</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Martin-Mur, Tomas J.; Kruizinga, Gerhard; Wong, Mau</p> <p>2013-01-01</p> <p>The Mars Science Laboratory spacecraft, carrying the Curiosity rover to Mars, hit the top of the Martian atmosphere just 200 meters from where it had been predicted more than six days earlier, and 2.6 million kilometers away. This un-expected level of accuracy was achieved by a combination of factors including: spacecraft performance, tracking data processing, dynamical modeling choices, and navigation filter setup. This paper will describe our best understanding of what were the factors that contributed to this excellent <span class="hlt">interplanetary</span> trajectory prediction performance. The accurate <span class="hlt">interplanetary</span> navigation contributed to the very precise landing performance, and to the overall success of the mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11776989','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11776989"><span>Radiation shielding of astronauts in <span class="hlt">interplanetary</span> flights: the CREAM surveyor to Mars and the <span class="hlt">magnetic</span> lens system for a spaceship.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Spillantini, P; Taccetti, F; Papini, P; Rossi, L; Casolino, M</p> <p>2001-01-01</p> <p>The radiation absorbed by astronauts during <span class="hlt">interplanetary</span> flights is mainly due to cosmic rays of solar origin (SCR). In the most powerful solar flares the dose absorbed in few hours can exceed that cumulated in one year of exposition to the galactic component of cosmic rays (GCR). At energies above the minimum one needed to cross the walls of the spaceship there are extrapolations and guesses, but no data, on the angular distribution of SCR's, an information that is necessary for establishing whatever defence strategy. It was therefore proposed of sending to Mars a measurement device, that should continuously collect data during the travel, and possibly also in the orbit around Mars and on the Mars surface. The device should identify the particle and privilege the completeness in the measurement of its parameters. In fact the high energy electrons travel at speed of the light and could be used in the and future dangerous proton component. Also the much less abundant but individually more dangerous ions should be identified. The device should indeed include a <span class="hlt">magnetic</span> spectrometer and a high granularity range telescope, and a good time of flight measurement. ASI is supporting an assessment study of a possible mission of such a device on board of the 2005 probe to Mars. A parallel technical study is also in progress to define the workable techniques and the possible configurations of a system of <span class="hlt">magnetic</span> lenses for protecting the crew of a spaceship.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ASPC..510..233B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ASPC..510..233B"><span>A Catalog of <span class="hlt">Averaged</span> <span class="hlt">Magnetic</span> Curves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bychkov, V. D.; Bychkova, L. V.; Madej, J.</p> <p>2017-06-01</p> <p>The second version of the catalog contains information about 275 stars of different types. Since the first catalog was created, the situation fundamentally changed primarily due to a significant increase of accuracy of <span class="hlt">magnetic</span> field (MF) measurements. Up to now, global <span class="hlt">magnetic</span> fields were discovered and measured in stars of many types and their behavior was partially studied. <span class="hlt">Magnetic</span> behavior of Ap/Bp stars was studied most thoroughly. The catalog contains data on 182 such objects. The main goals for the construction of the catalog are: 1) to review and summarize our knowledge about <span class="hlt">magnetic</span> behavior of stars of different types; 2) the whole data are uniformly presented and processed which will allow one to perform statistical analysis of the variability of (longitudinal) <span class="hlt">magnetic</span> fields of stars; 3) the data are presented in the most convenient way for testing different theoretical models; 4) the catalog will be useful for development of observational programs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhTea..56..114P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhTea..56..114P"><span>Measuring <span class="hlt">average</span> angular velocity with a smartphone <span class="hlt">magnetic</span> field sensor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pili, Unofre; Violanda, Renante</p> <p>2018-02-01</p> <p>The angular velocity of a spinning object is, by standard, measured using a device called a tachometer. However, by directly using it in a classroom setting, the activity is likely to appear as less instructive and less engaging. Indeed, some alternative classroom-suitable methods for measuring angular velocity have been presented. In this paper, we present a further alternative that is smartphone-based, making use of the real-time <span class="hlt">magnetic</span> field (simply called B-field in what follows) data gathering capability of the B-field sensor of the smartphone device as the timer for measuring <span class="hlt">average</span> rotational period and <span class="hlt">average</span> angular velocity. The in-built B-field sensor in smartphones has already found a number of uses in undergraduate experimental physics. For instance, in elementary electrodynamics, it has been used to explore the well-known Bio-Savart law and in a measurement of the permeability of air.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5648076','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5648076"><span>Filamentary field-aligned currents at the polar cap region during northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field derived with the Swarm constellation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lühr, Hermann; Huang, Tao; Wing, Simon; Kervalishvili, Guram; Rauberg, Jan; Korth, Haje</p> <p>2017-01-01</p> <p>ESA’s Swarm constellation mission makes it possible for the first time to determine field-aligned currents (FACs) in the ionosphere uniquely. In particular at high latitudes, the dual-satellite approach can reliably detect some FAC structures which are missed by the traditional single-satellite technique. These FAC events occur preferentially poleward of the auroral oval and during times of northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) orientation. Most events appear on the nightside. They are not related to the typical FAC structures poleward of the cusp, commonly termed NBZ. Simultaneously observed precipitating particle spectrograms and auroral images from Defense Meteorological Satellite Program (DMSP) satellites are consistent with the detected FACs and indicate that they occur on closed field lines mostly adjacent to the auroral oval. We suggest that the FACs are associated with Sun-aligned filamentary auroral arcs. Here we introduce in an initial study features of the high-latitude FAC structures which have been observed during the early phase of the Swarm mission. A more systematic survey over longer times is required to fully characterize the so far undetected field aligned currents. PMID:29056833</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015A%26A...582A..52A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015A%26A...582A..52A"><span>A tiny event producing an <span class="hlt">interplanetary</span> type III burst</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alissandrakis, C. E.; Nindos, A.; Patsourakos, S.; Kontogeorgos, A.; Tsitsipis, P.</p> <p>2015-10-01</p> <p>Aims: We investigate the conditions under which small-scale energy release events in the low corona gave rise to strong <span class="hlt">interplanetary</span> (IP) type III bursts. Methods: We analyzed observations of three tiny events, detected by the Nançay Radio Heliograph (NRH), two of which produced IP type III bursts. We took advantage of the NRH positioning information and of the high cadence of AIA/SDO data to identify the associated extreme-UV (EUV) emissions. We measured positions and time profiles of the metric and EUV sources. Results: We found that the EUV events that produced IP type III bursts were located near a coronal hole boundary, while the one that did not was located in a closed <span class="hlt">magnetic</span> field region. In all three cases tiny flaring loops were involved, without any associated mass eruption. In the best observed case, the radio emission at the highest frequency (435 MHz) was displaced by ~55'' with respect to the small flaring loop. The metric type III emission shows a complex structure in space and in time, indicative of multiple electron beams, despite the low intensity of the events. From the combined analysis of dynamic spectra and NRH images, we derived the electron beam velocity as well as the height, ambient plasma temperature, and density at the level of formation of the 160 MHz emission. From the analysis of the differential emission measure derived from the AIA images, we found that the first evidence of energy release was at the footpoints, and this was followed by the development of flaring loops and subsequent cooling. Conclusions: Even small energy release events can accelerate enough electrons to give rise to powerful IP type III bursts. The proximity of the electron acceleration site to open <span class="hlt">magnetic</span> field lines facilitates the escape of the electrons into the <span class="hlt">interplanetary</span> space. The offset between the site of energy release and the metric type III location warrants further investigation. The movie is available in electronic form at http://www.aanda.org</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140009615','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140009615"><span>The First in situ Observation of Kelvin-Helmholtz Waves at High-Latitude Magnetopause during Strongly Dawnward <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Conditions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hwang, K.-J.; Goldstein, M. L.; Kuznetsova, M. M.; Wang, Y.; Vinas, A. F.; Sibeck, D. G.</p> <p>2012-01-01</p> <p>We report the first in situ observation of high-latitude magnetopause (near the northern duskward cusp) Kelvin-Helmholtz waves (KHW) by Cluster on January 12, 2003, under strongly dawnward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) conditions. The fluctuations unstable to Kelvin-Helmholtz instability (KHI) are found to propagate mostly tailward, i.e., along the direction almost 90 deg. to both the magnetosheath and geomagnetic fields, which lowers the threshold of the KHI. The <span class="hlt">magnetic</span> configuration across the boundary layer near the northern duskward cusp region during dawnward IMF is similar to that in the low-latitude boundary layer under northward IMF, in that (1) both magnetosheath and magnetospheric fields across the local boundary layer constitute the lowest <span class="hlt">magnetic</span> shear and (2) the tailward propagation of the KHW is perpendicular to both fields. Approximately 3-hour-long periods of the KHW during dawnward IMF are followed by the rapid expansion of the dayside magnetosphere associated with the passage of an IMF discontinuity that characterizes an abrupt change in IMF cone angle, Phi = acos (B(sub x) / absolute value of Beta), from approx. 90 to approx. 10. Cluster, which was on its outbound trajectory, continued observing the boundary waves at the northern evening-side magnetopause during sunward IMF conditions following the passage of the IMF discontinuity. By comparing the signatures of boundary fluctuations before and after the IMF discontinuity, we report that the frequencies of the most unstable KH modes increased after the discontinuity passed. This result demonstrates that differences in IMF orientations (especially in f) are associated with the properties of KHW at the high-latitude magnetopause due to variations in thickness of the boundary layer, and/or width of the KH-unstable band on the surface of the dayside magnetopause.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12804366','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12804366"><span>Fullerenes and <span class="hlt">interplanetary</span> dust at the Permian-Triassic boundary.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Poreda, Robert J; Becker, Luann</p> <p>2003-01-01</p> <p>We recently presented new evidence that an impact occurred approximately 250 million years ago at the Permian-Triassic boundary (PTB), triggering the most severe mass extinction in the history of life on Earth. We used a new extraterrestrial tracer, fullerene, a third carbon carrier of noble gases besides diamond and graphite. By exploiting the unique properties of this molecule to trap noble gases inside of its caged structure (helium, neon, argon), the origin of the fullerenes can be determined. Here, we present new evidence for fullerenes with extraterrestrial noble gases in the PTB at Graphite Peak, Antarctica, similar to PTB fullerenes from Meishan, China and Sasayama, Japan. In addition, we isolated a (3)He-rich <span class="hlt">magnetic</span> carrier phase in three fractions from the Graphite Peak section. The noble gases in this <span class="hlt">magnetic</span> fraction were similar to zero-age deep-sea <span class="hlt">interplanetary</span> dust particles (IDPs) and some <span class="hlt">magnetic</span> grains isolated from the Cretaceous-Tertiary boundary. The helium and neon isotopic compositions for both the bulk Graphite Peak sediments and an isolated <span class="hlt">magnetic</span> fraction from the bulk material are consistent with solar-type gases measured in zero-age deep-sea sediments and point to a common source, namely, the flux of IDPs to the Earth's surface. In this instance, the IDP noble gas signature for the bulk sediment can be uniquely decoupled from fullerene, demonstrating that two separate tracers are present (direct flux of IDPs for (3)He vs. giant impact for fullerene).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120016557&hterms=understand&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dunderstand','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120016557&hterms=understand&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dunderstand"><span>Using Statistical Multivariable Models to Understand the Relationship Between <span class="hlt">Interplanetary</span> Coronal Mass Ejecta and <span class="hlt">Magnetic</span> Flux Ropes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Riley, P.; Richardson, I. G.</p> <p>2012-01-01</p> <p>In-situ measurements of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) display a wide range of properties. A distinct subset, "<span class="hlt">magnetic</span> clouds" (MCs), are readily identifiable by a smooth rotation in an enhanced <span class="hlt">magnetic</span> field, together with an unusually low solar wind proton temperature. In this study, we analyze Ulysses spacecraft measurements to systematically investigate five possible explanations for why some ICMEs are observed to be MCs and others are not: i) An observational selection effect; that is, all ICMEs do in fact contain MCs, but the trajectory of the spacecraft through the ICME determines whether the MC is actually encountered; ii) interactions of an erupting flux rope (PR) with itself or between neighboring FRs, which produce complex structures in which the coherent <span class="hlt">magnetic</span> structure has been destroyed; iii) an evolutionary process, such as relaxation to a low plasma-beta state that leads to the formation of an MC; iv) the existence of two (or more) intrinsic initiation mechanisms, some of which produce MCs and some that do not; or v) MCs are just an easily identifiable limit in an otherwise corntinuous spectrum of structures. We apply quantitative statistical models to assess these ideas. In particular, we use the Akaike information criterion (AIC) to rank the candidate models and a Gaussian mixture model (GMM) to uncover any intrinsic clustering of the data. Using a logistic regression, we find that plasma-beta, CME width, and the ratio O(sup 7) / O(sup 6) are the most significant predictor variables for the presence of an MC. Moreover, the propensity for an event to be identified as an MC decreases with heliocentric distance. These results tend to refute ideas ii) and iii). GMM clustering analysis further identifies three distinct groups of ICMEs; two of which match (at the 86% level) with events independently identified as MCs, and a third that matches with non-MCs (68 % overlap), Thus, idea v) is not supported. Choosing between ideas i) and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004ESASP.548..387B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004ESASP.548..387B"><span>ESOC's System for <span class="hlt">Interplanetary</span> Orbit Determination: Implementation and Operational Experience</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Budnik, F.; Morley, T. A.; MacKenzie, R. A.</p> <p></p> <p>A system for <span class="hlt">interplanetary</span> orbit determination has been developed at ESOC over the past six years. Today, the system is in place and has been proven to be both reliable and robust by successfully supporting critical operations of ESA's <span class="hlt">interplanetary</span> spacecraft Rosetta, Mars Express, and SMART-1. To reach this stage a long and challenging way had to be travelled. This paper gives a digest about the journey from the development and testing to the operational use of ESOC's new <span class="hlt">interplanetary</span> orbit determination system. It presents the capabilities and reflects experiences gained from the performed tests and tracking campaigns.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930005541','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930005541"><span><span class="hlt">Interplanetary</span> Program to Optimize Simulated Trajectories (IPOST). Volume 3: Programmer's manual</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hong, P. E.; Kent, P. D.; Olson, D. W.; Vallado, C. A.</p> <p>1992-01-01</p> <p>The <span class="hlt">Interplanetary</span> Program to Optimize Space Trajectories (IPOST) is intended to support many analysis phases, from early <span class="hlt">interplanetary</span> feasibility studies through spacecraft development and operations. Here, information is given on the IPOST code.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19930049649&hterms=Fast+radio+burst&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DFast%2Bradio%2Bburst','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19930049649&hterms=Fast+radio+burst&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DFast%2Bradio%2Bburst"><span><span class="hlt">Interplanetary</span> fast shock diagnosis with the radio receiver on Ulysses</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoang, S.; Pantellini, F.; Harvey, C. C.; Lacombe, C.; Mangeney, A.; Meuer-Vernet, N.; Perche, C.; Steinberg, J.-L.; Lengyel-Frey, D.; Macdowall, R. J.</p> <p>1992-01-01</p> <p>The radio receiver on Ulysses records the quasi-thermal noise which allows a determination of the density and temperature of the cold (core) electrons of the solar wind. Seven <span class="hlt">interplanetary</span> fast forward or reverse shocks are identified from the density and temperature profiles, together with the <span class="hlt">magnetic</span> field profile from the Magnetometer experiment. Upstream of the three strongest shocks, bursts of nonthermal waves are observed at the electron plasma frequency f(peu). The more perpendicular the shock, the longer the time interval during which these upstream bursts are observed. For one of the strongest shocks we also observe two kinds of upstream electromagnetic radiation: radiation at 2 f(peu), and radiation at the downstream electron plasma frequency, which propagates into the less dense upstream regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060041678&hterms=WIND+STORMS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWIND%2BSTORMS','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060041678&hterms=WIND+STORMS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWIND%2BSTORMS"><span>Distant Tail Behavior During High Speed Solar Wind Streams and <span class="hlt">Magnetic</span> Storms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ho, C. M.; Tsurutani, B. T.</p> <p>1997-01-01</p> <p>We have examined the ISEE 3 distant tail data during three intense <span class="hlt">magnetic</span> storms and have identified the tail response to high-speed solar wind streams, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds, and near-Earth storms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910040049&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DOpen%2BField','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910040049&hterms=Open+Field&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DOpen%2BField"><span>Observations of disconnection of open coronal <span class="hlt">magnetic</span> structures</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mccomas, D. J.; Phillips, J. L.; Hundhausen, A. J.; Burkepile, J. T.</p> <p>1991-01-01</p> <p>The solar maximum mission coronagraph/polarimeter observations are surveyed for evidence of <span class="hlt">magnetic</span> disconnection of previously open <span class="hlt">magnetic</span> structures and several sequences of images consistent with this interpretation are identified. Such disconnection occurs when open field lines above helmet streamers reconnect, in contrast to previously suggested disconnections of CMEs into closed plasmoids. In this paper a clear example of open field disconnection is shown in detail. The event, on June 27, 1988, is preceded by compression of a preexisting helmet streamer and the open coronal field around it. The compressed helmet streamer and surrounding open field region detach in a large U-shaped structure which subsequently accelerates outward from the sun. The observed sequence of events is consistent with reconnection across the heliospheric current sheet and the creation of a detached U-shaped <span class="hlt">magnetic</span> structure. Unlike CMEs, which may open new <span class="hlt">magnetic</span> flux into <span class="hlt">interplanetary</span> space, this process could serve to close off previously open flux, perhaps helping to maintain the roughly constant amount of open <span class="hlt">magnetic</span> flux observed in <span class="hlt">interplanetary</span> space.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150018311','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150018311"><span>Time Delay Between Dst Index and <span class="hlt">Magnetic</span> Storm Related Structure in the Solar Wind</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Osherovich, Vladimir A.; Fainberg, Joseph</p> <p>2015-01-01</p> <p>Benson et al. (2015, this volume) selected 10 large <span class="hlt">magnetic</span> storms, with associated Dst minimum values less than or equal to -100 nT, for which high-latitude topside ionospheric electron density profiles are available from topside-sounder satellites. For these 10 storms, we performed a superposition of Dst and <span class="hlt">interplanetary</span> parameters B, v, N(sub p) and T(sub p). We have found that two <span class="hlt">interplanetary</span> parameters, namely B and v, are sufficient to reproduce Dst with correlation coefficient cc approximately 0.96 provided that the <span class="hlt">interplanetary</span> parameter times are taken 0.15 days earlier than the associated Dst times. Thus we have found which part of the solar wind is responsible for each phase of the <span class="hlt">magnetic</span> storm. This result is also verified for individual storms as well. The total duration of SRS (storm related structure in the solar wind) is 4 - 5 days which is the same as the associated Dst interval of the <span class="hlt">magnetic</span> storm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002cosp...34E1203R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002cosp...34E1203R"><span>Comparison of <span class="hlt">magnetic</span> helicity close to the sun and in <span class="hlt">magnetic</span> clouds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rust, D.</p> <p></p> <p><span class="hlt">Magnetic</span> helicity is present in the solar atmosphere - as inferred from vector magnetograph measurements, solar filaments, S-shaped coronal structures known as sigmoids, and sunspot whorls. I will survey the possible solar sources of this <span class="hlt">magnetic</span> helicity. Included are fieldline footpoint motions, effects of Coriolis forces, effects of convection, shear associated with differential rotation, and, of course, the internal dynamo. Besides the survey of possible local mechanisms for helicity generation, I will consider the global view of the flow of helicity from the sun into <span class="hlt">interplanetary</span> space. The principal agents by which the sun sheds helicity are coronal mass ejections (CMEs). They are often associated with <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds (MCs), whose fields are regularly probed with sensitive spacecraft magnetometers. MCs yield more direct measurements of helicity. They show that each MC carries helicity away from the sun. A major issue in solar-heliospheric research is whether the amount of helicity that MCs carry away in a solar cycle can be accounted for by the helicity generation mechanisms proposed so far. The NASA Solar and Heliospheric Physics Program supports this work under grants NAG5- 7921 and NAG 5-11584.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003SoPh..213..147B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003SoPh..213..147B"><span>A new Method for Determining the <span class="hlt">Interplanetary</span> Current-Sheet Local Orientation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blanco, J. J.; Rodríguez-pacheco, J.; Sequeiros, J.</p> <p>2003-03-01</p> <p>In this work we have developed a new method for determining the <span class="hlt">interplanetary</span> current sheet local parameters. The method, called `HYTARO' (from Hyperbolic Tangent Rotation), is based on a modified Harris <span class="hlt">magnetic</span> field. This method has been applied to a pool of 57 events, all of them recorded during solar minimum conditions. The model performance has been tested by comparing both, its outputs and noise response, with these of the `classic MVM' (from Minimum Variance Method). The results suggest that, despite the fact that in many cases they behave in a similar way, there are specific crossing conditions that produce an erroneous MVM response. Moreover, our method shows a lower noise level sensitivity than that of MVM.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSA23B2400T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSA23B2400T"><span>Reconstruction of F-Region Electric Current Densities from more than 2 Years of Swarm Satellite <span class="hlt">Magnetic</span> data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tozzi, R.; Pezzopane, M.; De Michelis, P.; Pignalberi, A.; Siciliano, F.</p> <p>2016-12-01</p> <p>The constellation geometry adopted by ESA for Swarm satellites has opened the way to new investigations based on <span class="hlt">magnetic</span> data. An example is the curl-B technique that allows reconstructing F-region electric current density in terms of its radial, meridional, and zonal components based on data from two satellites of Swarm constellation (Swarm A and B) which fly at different altitudes. Here, we apply this technique to more than 2 years of Swarm <span class="hlt">magnetic</span> vector data and investigate the <span class="hlt">average</span> large scale behaviour of F-region current densities as a function of local time, season and different <span class="hlt">interplanetary</span> conditions (different strength and direction of the three IMF components and/or geomagnetic activity levels).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720000603','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720000603"><span><span class="hlt">Interplanetary</span> Trajectories, Encke Method (ITEM)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Whitlock, F. H.; Wolfe, H.; Lefton, L.; Levine, N.</p> <p>1972-01-01</p> <p>Modified program has been developed using improved variation of Encke method which avoids accumulation of round-off errors and avoids numerical ambiguities arising from near-circular orbits of low inclination. Variety of <span class="hlt">interplanetary</span> trajectory problems can be computed with maximum accuracy and efficiency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070014640','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070014640"><span>Software Risk Identification for <span class="hlt">Interplanetary</span> Probes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dougherty, Robert J.; Papadopoulos, Periklis E.</p> <p>2005-01-01</p> <p>The need for a systematic and effective software risk identification methodology is critical for <span class="hlt">interplanetary</span> probes that are using increasingly complex and critical software. Several probe failures are examined that suggest more attention and resources need to be dedicated to identifying software risks. The direct causes of these failures can often be traced to systemic problems in all phases of the software engineering process. These failures have lead to the development of a practical methodology to identify risks for <span class="hlt">interplanetary</span> probes. The proposed methodology is based upon the tailoring of the Software Engineering Institute's (SEI) method of taxonomy-based risk identification. The use of this methodology will ensure a more consistent and complete identification of software risks in these probes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870064137&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dfaraday','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870064137&hterms=faraday&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dfaraday"><span>The mean coronal <span class="hlt">magnetic</span> field determined from Helios Faraday rotation measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Patzold, M.; Bird, M. K.; Volland, H.; Levy, G. S.; Seidel, B. L.; Stelzried, C. T.</p> <p>1987-01-01</p> <p>Coronal Faraday rotation of the linearly polarized carrier signals of the Helios spacecraft was recorded during the regularly occurring solar occultations over almost a complete solar cycle from 1975 to 1984. These measurements are used to determine the <span class="hlt">average</span> strength and radial variation of the coronal <span class="hlt">magnetic</span> field at solar minimum at solar distances from 3-10 solar radii, i.e., the range over which the complex fields at the coronal base are transformed into the <span class="hlt">interplanetary</span> spiral. The mean coronal <span class="hlt">magnetic</span> field in 1975-1976 was found to decrease with radial distance according to r exp-alpha, where alpha = 2.7 + or - 0.2. The mean field magnitude was 1.0 + or - 0.5 x 10 to the -5th tesla at a nominal solar distance of 5 solar radii. Possibly higher <span class="hlt">magnetic</span> field strengths were indicated at solar maximum, but a lack of data prevented a statistical determination of the mean coronal field during this epoch.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5839089-interplanetary-magnetic-field-sub-dependent-field-aligned-current-dayside-polar-cap-under-quiet-conditions','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5839089-interplanetary-magnetic-field-sub-dependent-field-aligned-current-dayside-polar-cap-under-quiet-conditions"><span>The <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field B sub y -dependent field-aligned current in the dayside polar cap under quiet conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Yamauchi, M.; Araki, T.</p> <p>1989-03-01</p> <p>Spatial distribution and temporal variation of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) B{sub y}-dependent cusp region field-aligned currents (FACs) during quiet periods were studied by use of <span class="hlt">magnetic</span> data observed by Magsat. The analysis was made for 11 events (each event lasts more than one and a half days) when the IMF B{sub y} component was steadily large and B{sub x} was relatively small ({vert bar}B{sub z}{vert bar} < {vert bar}B{sub y}{vert bar}). Results of the analysis of total 62 half-day periods for the IMF B{sub y}-dependent cusp region FAC are summarized as follows: (1) the IMF B{sub y}-dependent cusp regionmore » FAC is located at around 86{degree}-87{degree} invariant latitude local noon, which is more poleward than the location of the IMF B{sub z}-dependent cusp region FAC; (2) the current density of this FAC is greater than previous studies ({ge} 4 {mu}A/m{sup 2} for IMF B{sub y} = 6 nT); (3) there are two time scales for the IMF B{sub y}-dependent cusp region FAC to appear: the initial rise of the current is on a short time scale, {approximately} 10 min, and it is followed by a gradual increase on a time scale of several hours to a half day; (4) the seasonal change of this FAC is greater than that of the nightside region 1 or region 2 FACs; (5) the IMF B{sub z}-dependent cusp region FAC is not well observed around the cusp when the IMF B{sub y}-dependent cusp region FAC is intense.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38.2220D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38.2220D"><span>Characteristics of magnetised plasma flow around stationary and expanding <span class="hlt">magnetic</span> clouds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dalakishvili, Giorgi</p> <p></p> <p>Studies of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds have shown that the characteristics of the region ahead of these objects, which are moving away from the Sun in the solar wind, play a role in determining their geo-efficiency, i.e. the kind and the degree of their effects on the Earth environment. Therefore, our main goal is to model and study the plasma parameters in the vicinity of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds. To this end we present a model in which the <span class="hlt">magnetic</span> clouds are immersed in a magnetised plasma flow with a homogeneous <span class="hlt">magnetic</span> field. We first calculate the resulting distortion of the external <span class="hlt">magnetic</span> field and then determine the plasma velocity by employing the frozen-in condition. Subsequently, the plasma density and pressure are expressed as functions of the <span class="hlt">magnetic</span> field and the velocity field. The plasma flow parameters are determined by solving the time-independent ideal MHD equations for both the stationary regime and for the case of an expand-ing cylindrical <span class="hlt">magnetic</span> cloud, thus extending previous results that appeared in the literature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001DPS....33.3901H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001DPS....33.3901H"><span>Velocity Distributions of <span class="hlt">Interplanetary</span> Dust Derived from Astronomical Sky Spectra</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huestis, D. L.; Ali, S.; Cosby, P. C.; Slanger, T. G.</p> <p>2001-11-01</p> <p>Characterization of <span class="hlt">interplanetary</span> dust is important for understanding the creation by accretion of planets and moons, the development of planetary atmospheres, and, potentially, for the initiation of prebiotic chemistry. The recent COBE mission has provided a profile in ecliptic coordinates of the distribution of <span class="hlt">interplanetary</span> dust particles through their thermal infrared emission. Additional information about <span class="hlt">interplanetary</span> dust can be extracted from its visible spectrum of scattered sunlight, called Zodiacal Light. Night sky spectra taken at large-aperture telescopes using high-resolution echelle spectrographs reveal Fraunhofer absorption features in the Zodiacal Light spectrum of scattered sunlight, a nuisance in subtraction from the spectrum of the extraterrestrial object under investigation. We are analyzing the intensity modulations and Doppler shifts of solar Fraunhofer absorption lines in the Zodiacal Light component of sky spectra, donated by collaborating astronomers using Keck/HIRES and other high-performance astronomical facilities. Our objectives include velocity distributions of <span class="hlt">interplanetary</span> dust and improved separation of terrestrial and extraterrestrial sources in sky spectra. Participation of S. Ali was made possible by a grant from the NSF Physics Research Experiences for Undergraduates (REU) program.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012epsc.conf..117D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012epsc.conf..117D"><span><span class="hlt">Interplanetary</span> laser ranging - an emerging technology for planetary science missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dirkx, D.; Vermeersen, L. L. A.</p> <p>2012-09-01</p> <p><span class="hlt">Interplanetary</span> laser ranging (ILR) is an emerging technology for very high accuracy distance determination between Earth-based stations and spacecraft or landers at <span class="hlt">interplanetary</span> distances. It has evolved from laser ranging to Earth-orbiting satellites, modified with active laser transceiver systems at both ends of the link instead of the passive space-based retroreflectors. It has been estimated that this technology can be used for mm- to cm-level accuracy range determination at <span class="hlt">interplanetary</span> distances [2, 7]. Work is being performed in the ESPaCE project [6] to evaluate in detail the potential and limitations of this technology by means of bottom-up laser link simulation, allowing for a reliable performance estimate from mission architecture and hardware characteristics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950057064&hterms=recurrence+sequences&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Drecurrence%2Bsequences','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950057064&hterms=recurrence+sequences&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Drecurrence%2Bsequences"><span>Cusp/cleft auroral activity in relation to solar wind dynamic pressure, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field B(sub z) and B(sub y)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sandholt, P. E.; Farrugia, C. J.; Burlaga, L. F.; Holtet, J. A.; Moen, J.; Lybekk, B.; Jacobsen, B.; Opsvik, D.; Egeland, A.; Lepping, R.</p> <p>1994-01-01</p> <p>Continuous optical observations of cusp/cleft auroral activities within approximately equal to 09-15 MLT and 70-76 deg <span class="hlt">magnetic</span> latitude are studied in relation to changes in solar wind dynamic pressure and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) variability. The observed latitudinal movements of the cusp/cleft aurora in response to IMF B(sub z) changes may be explained as an effect of a variable <span class="hlt">magnetic</span> field intensity in the outer dayside magnetosphere associated with the changing intensity of region 1 field-aligned currents and associated closure currents. Ground <span class="hlt">magnetic</span> signatures related to such currents were observed in the present case (January 10, 1993). Strong, isolated enhancements in solar wind dynamic pressure (Delta p/p is greater than or equal to 0.5) gave rise to equatorward shifts of the cusp/cleft aurora, characteristic auroral transients, and distinct ground <span class="hlt">magnetic</span> signatures of enhanced convection at cleft latitudes. A sequence of auroral events of approximately equal to 5-10 min recurrence time, moving eastward along the poleward boundary of the persistent cusp/cleft aurora in the approximately equal to 10-14 MLT sector, during negative IMF B(sub z) and B(sub y) conditions, were found to be correlated with brief pulses in solar wind dynamic pressure (0.1 is less than Delta p/p is less than 0.5). Simultaneous photometer observations from Ny Alesund, Svalbard, and Danmarkshavn, Greenland, show that the events often appeared on the prenoon side (approximately equal to 10-12 MLT), before moving into the postnoon sector in the case we study here, when IMF B(sub y) is less than 0. In other cases, similar auroral event sequences have been observed to move westward in the prenoon sector, during intervals of positive B(sub y). Thus a strong prenoon/postnoon asymmetry of event occurence and motion pattern related to the IMF B(sub y) polarity is observed. We find that this category of auroral event sequence is stimulated bursts of electron precipitation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910012840','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910012840"><span>Use of <span class="hlt">magnetic</span> sails for advanced exploration missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Andrews, Dana G.; Zubrin, Robert M.</p> <p>1990-01-01</p> <p>The <span class="hlt">magnetic</span> sail, or magsail, is a field effect device which interacts with the ambient solar wind or interstellar medium over a considerable volume of space to generate drag and lift forces. Two theories describing the method of thrust generation are analyzed and data results are presented. The techniques for maintaining superconductor temperatures in <span class="hlt">interplanetary</span> space are analyzed and low risk options presented. Comparisons are presented showing mission performance differences between currently proposed spacecraft using chemical and electric propulsion systems, and a Magsail propelled spacecraft capable of generating an <span class="hlt">average</span> thrust of 250 Newtons at a radius of one A.U. The magsail also provides unique capabilities for interstellar missions, in that at relativistic speeds the <span class="hlt">magnetic</span> field would ionize and deflect the interstellar medium producing a large drag force. This would make it an ideal brake for decelerating a spacecraft from relativistic speeds and then maneuvering within the target star system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015P%26SS..117...15L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015P%26SS..117...15L"><span>Solar wind interaction effects on the <span class="hlt">magnetic</span> fields around Mars: Consequences for <span class="hlt">interplanetary</span> and crustal field measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luhmann, J. G.; Ma, Y.-J.; Brain, D. A.; Ulusen, D.; Lillis, R. J.; Halekas, J. S.; Espley, J. R.</p> <p>2015-11-01</p> <p>The first unambiguous detections of the crustal remanent <span class="hlt">magnetic</span> fields of Mars were obtained by Mars Global Surveyor (MGS) during its initial orbits around Mars, which probed altitudes to within ∼110 km of the surface. However, the majority of its measurements were carried out around 400 km altitude, fixed 2 a.m. to 2 p.m. local time, mapping orbit. While the general character and planetary origins of the localized crustal fields were clearly revealed by the mapping survey data, their effects on the solar wind interaction could not be investigated in much detail because of the limited mapping orbit sampling. Previous analyses (Brain et al., 2006) of the field measurements on the dayside nevertheless provided an idea of the extent to which the interaction of the solar wind and planetary fields leads to non-ideal field draping at the mapping altitude. In this study we use numerical simulations of the global solar wind interaction with Mars as an aid to interpreting that observed non-ideal behavior. In addition, motivated by models for different <span class="hlt">interplanetary</span> field orientations, we investigate the effects of induced and reconnected (planetary and external) fields on the Martian field's properties derived at the MGS mapping orbit altitude. The results suggest that inference of the planetary low order moments is compromised by their influence. In particular, the intrinsic dipole contribution may differ from that in the current models because the induced component is so dominant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950007245','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950007245"><span><span class="hlt">Interplanetary</span> medium data book, supplement 5, 1988-1993</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>King, Joseph H.; Papitashvili, Natalia E.</p> <p>1994-01-01</p> <p>This publication represents an extension of the series of <span class="hlt">Interplanetary</span> Medium Data Books and supplements that have been issued by the National Space Science Data Center since 1977. This volume contains solar wind <span class="hlt">magnetic</span> field and plasma data from the IMP 8 spacecraft for 1988 through the end of 1993. The normalization of the MIT plasma density and temperature, which has been discussed at length in previous volumes, is implemented as before, using the same normalization constants for 1988-1993 data as for the earlier data. Owing to a combination of non-continuity of IMP 8 telemetry acquisition and IMP's being out of the solar wind for about 40 percent of its orbit, the annual solar wind coverage for 1988-1993 is 40 plus or minus 5 percent. The plots and listings of this supplement are in essentially the same format as in previous supplements. Days for which neither IMF nor plasma data were available for any hours are omitted from the listings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70011277','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70011277"><span>Statistical <span class="hlt">averaging</span> of marine <span class="hlt">magnetic</span> anomalies and the aging of oceanic crust.</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Blakely, R.J.</p> <p>1983-01-01</p> <p>Visual comparison of Mesozoic and Cenozoic <span class="hlt">magnetic</span> anomalies in the North Pacific suggests that older anomalies contain less short-wavelength information than younger anomalies in this area. To test this observation, <span class="hlt">magnetic</span> profiles from the North Pacific are examined from crust of three ages: 0-2.1, 29.3-33.1, and 64.9-70.3Ma. For each time period, at least nine profiles were analyzed by 1) calculating the power density spectrum of each profile, 2) <span class="hlt">averaging</span> the spectra together, and 3) computing a 'recording filter' for each time period by assuming a hypothetical seafloor model. The model assumes that the top of the source is acoustic basement, the source thickness is 0.5km, and the time scale of geomagnetic reversals is according to Ness et al. (1980). The calculated power density spectra of the three recording filters are complex in shape but show an increase of attenuation of short-wavelength information as the crust ages. These results are interpreted using a multilayer model for marine <span class="hlt">magnetic</span> anomalies in which the upper layer, corresponding to pillow basalt of seismic layer 2A, acts as a source of noise to the <span class="hlt">magnetic</span> anomalies. As the ocean crust ages, this noisy contribution by the pillow basalts becomes less significant to the anomalies. Consequently, <span class="hlt">magnetic</span> sources below layer 2A must be faithful recorders of geomagnetic reversals.-AuthorPacific power density spectrum</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19970026865','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19970026865"><span>Kuiper Belt Dust Grains as a Source of <span class="hlt">Interplanetary</span> Dust Particles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.</p> <p>1996-01-01</p> <p>The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the <span class="hlt">interplanetary</span> dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar <span class="hlt">magnetic</span> field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected <span class="hlt">interplanetary</span> dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the <span class="hlt">interplanetary</span> dust complex in the inner Solar</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060036372&hterms=WIND+STORMS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWIND%2BSTORMS','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060036372&hterms=WIND+STORMS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWIND%2BSTORMS"><span>(abstract) The Distant Tail Behavior During High Speed Solar Wind Streams and <span class="hlt">Magnetic</span> Storms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ho, C. M.; Tsurutani, B. T.</p> <p>1996-01-01</p> <p>We have examined the ISEE-3 distant tail data during three intense <span class="hlt">magnetic</span> storms and have identified the tail response to high speed solar wind streams, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds, and near-Earth storms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22661357-anatomy-depleted-interplanetary-coronal-mass-ejections','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22661357-anatomy-depleted-interplanetary-coronal-mass-ejections"><span>ANATOMY OF DEPLETED <span class="hlt">INTERPLANETARY</span> CORONAL MASS EJECTIONS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kocher, M.; Lepri, S. T.; Landi, E.</p> <p></p> <p>We report a subset of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) containing distinct periods of anomalous heavy-ion charge state composition and peculiar ion thermal properties measured by ACE /SWICS from 1998 to 2011. We label them “depleted ICMEs,” identified by the presence of intervals where C{sup 6+}/C{sup 5+} and O{sup 7+}/O{sup 6+} depart from the direct correlation expected after their freeze-in heights. These anomalous intervals within the depleted ICMEs are referred to as “Depletion Regions.” We find that a depleted ICME would be indistinguishable from all other ICMEs in the absence of the Depletion Region, which has the defining property ofmore » significantly low abundances of fully charged species of helium, carbon, oxygen, and nitrogen. Similar anomalies in the slow solar wind were discussed by Zhao et al. We explore two possibilities for the source of the Depletion Region associated with <span class="hlt">magnetic</span> reconnection in the tail of a CME, using CME simulations of the evolution of two Earth-bound CMEs described by Manchester et al.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840051069&hterms=media+influence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dmedia%2Binfluence','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840051069&hterms=media+influence&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dmedia%2Binfluence"><span>Hydromagnetic waves, turbulence, and collisionless processes in the <span class="hlt">interplanetary</span> medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Barnes, A.</p> <p>1983-01-01</p> <p>An extended discussion is conducted concerning the origin and evolution of <span class="hlt">interplanetary</span> hydromagnetic waves and turbulence, and their influence on the large scale dynamics of the solar wind. The solar wind is at present the preeminent medium for the study of hydromagnetic waves and turbulence, providing an opportunity for advancement of understanding of the most fundamental processes of the astrophysical plasmas. All <span class="hlt">interplanetary</span> fluctuations whose time scale is observed to be greater than 1 sec can be regarded as hydromagnetic fluctuations. It has been found to be simplest, and generally very satisfactory, to model <span class="hlt">interplanetary</span> variations as fluctuations in an MHD fluid. Attention is given to the classification of wave modes, geometrical hydromagnetics, Alfven wave pressure, rugged invariants, and the kinetic theory of collisionless processes.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.3049J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.3049J"><span><span class="hlt">Interplanetary</span> Dust Observations by the Juno MAG Investigation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jørgensen, John; Benn, Mathias; Denver, Troelz; Connerney, Jack; Jørgensen, Peter; Bolton, Scott; Brauer, Peter; Levin, Steven; Oliversen, Ronald</p> <p>2017-04-01</p> <p>The spin-stabilized and solar powered Juno spacecraft recently concluded a 5-year voyage through the solar system en route to Jupiter, arriving on July 4th, 2016. During the cruise phase from Earth to the Jovian system, the Magnetometer investigation (MAG) operated two <span class="hlt">magnetic</span> field sensors and four co-located imaging systems designed to provide accurate attitude knowledge for the MAG sensors. One of these four imaging sensors - camera "D" of the Advanced Stellar Compass (ASC) - was operated in a mode designed to detect all luminous objects in its field of view, recording and characterizing those not found in the on-board star catalog. The capability to detect and track such objects ("non-stellar objects", or NSOs) provides a unique opportunity to sense and characterize <span class="hlt">interplanetary</span> dust particles. The camera's detection threshold was set to MV9 to minimize false detections and discourage tracking of known objects. On-board filtering algorithms selected only those objects tracked through more than 5 consecutive images and moving with an apparent angular rate between 15"/s and 10,000"/s. The coordinates (RA, DEC), intensity, and apparent velocity of such objects were stored for eventual downlink. Direct detection of proximate dust particles is precluded by their large (10-30 km/s) relative velocity and extreme angular rates, but their presence may be inferred using the collecting area of Juno's large ( 55m2) solar arrays. Dust particles impact the spacecraft at high velocity, creating an expanding plasma cloud and ejecta with modest (few m/s) velocities. These excavated particles are revealed in reflected sunlight and tracked moving away from the spacecraft from the point of impact. Application of this novel detection method during Juno's traversal of the solar system provides new information on the distribution of <span class="hlt">interplanetary</span> (µm-sized) dust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800026573&hterms=survey+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dsurvey%2Bresearch','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800026573&hterms=survey+research&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dsurvey%2Bresearch"><span><span class="hlt">Interplanetary</span> dust. [survey of last four years' research</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Brownlee, D. E.</p> <p>1979-01-01</p> <p>Progress in the study of <span class="hlt">interplanetary</span> dust during the past four years is reviewed. Attention is given to determinations of the relative contributions of interstellar dust grains, collisional debris from the asteroid belt and short-period comets to the <span class="hlt">interplanetary</span> dust cloud. Effects of radiation pressure and collisions on particle dynamics are discussed, noting the discovery of the variation of the orbital parameters of dust particles at 1 AU with size and in situ measurements of dust density between 0.3 and 5 AU by the Helios and Pioneer spacecraft. The interpretation of the zodiacal light as produced by porous absorbing particles 10 to 100 microns in size is noted, and measurements of the Doppler shift, light-producing-particle density, UV spectrum, photometric axis and angular scattering function of the zodiacal light are reported. Results of analyses of lunar rock microcraters as to micrometeoroid density, flux rate, size distribution and composition are indicated and <span class="hlt">interplanetary</span> dust particles collected from the stratosphere are discussed. Findings concerning the composition of fragile meteoroid types found as cosmic spherules in deep sea sediments are also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950047150&hterms=PHOTOIONIZATION&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DPHOTOIONIZATION','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950047150&hterms=PHOTOIONIZATION&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DPHOTOIONIZATION"><span>Solar photoionization as a loss mechanism of neutral interstellar hydrogen in <span class="hlt">interplanetary</span> space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ogawa, H. S.; Wu, C. Y. Robert; Gangopadhyay, P.; Judge, D. L.</p> <p>1995-01-01</p> <p>Two primary loss mechanisms of interstellar neutral hydrogen in <span class="hlt">interplanetary</span> space are resonance charge exchange ionization with solar wind protons and photoionization by solar EUV radiation. The later process has often been neglected since the <span class="hlt">average</span> photoionization rate has been estimated to be as much as 5 to 10 times smaller than the charge exchange rate. These factors are based on ionization rates from early measurements of solar EUV and solar wind fluxes. Using revised solar EUV and solar wind fluxes measured near the ecliptic plane we have reinvestigated the ionization rates of <span class="hlt">interplanetary</span> hydrogen. The result of our analysis indicates that indeed the photoionization rate during solar minimum can be smaller than charge exchange by a factor of 5; however, during solar maximum conditions when solar EUV fluxes are high, and solar wind fluxes are low, photoionization can be over 60% of the charge exchange rate at Earth orbit. To obtain an accurate estimate of the importance of photoionization relative to charge exchange, we have included photoionization from both the ground and metastable states of hydrogen. We find, however, that the photoionization from the metastable state does not contribute significantly to the overall photoionization rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH41B2774K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH41B2774K"><span>A Statistical Study of <span class="hlt">Interplanetary</span> Type II Bursts: STEREO Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krupar, V.; Eastwood, J. P.; Magdalenic, J.; Gopalswamy, N.; Kruparova, O.; Szabo, A.</p> <p>2017-12-01</p> <p>Coronal mass ejections (CMEs) are the primary cause of the most severe and disruptive space weather events such as solar energetic particle (SEP) events and geomagnetic storms at Earth. <span class="hlt">Interplanetary</span> type II bursts are generated via the plasma emission mechanism by energetic electrons accelerated at CME-driven shock waves and hence identify CMEs that potentially cause space weather impact. As CMEs propagate outward from the Sun, radio emissions are generated at progressively at lower frequencies corresponding to a decreasing ambient solar wind plasma density. We have performed a statistical study of 153 <span class="hlt">interplanetary</span> type II bursts observed by the two STEREO spacecraft between March 2008 and August 2014. These events have been correlated with manually-identified CMEs contained in the Heliospheric Cataloguing, Analysis and Techniques Service (HELCATS) catalogue. Our results confirm that faster CMEs are more likely to produce <span class="hlt">interplanetary</span> type II radio bursts. We have compared observed frequency drifts with white-light observations to estimate angular deviations of type II burst propagation directions from radial. We have found that <span class="hlt">interplanetary</span> type II bursts preferably arise from CME flanks. Finally, we discuss a visibility of radio emissions in relation to the CME propagation direction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950029559&hterms=convection+currents&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dconvection%2Bcurrents','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950029559&hterms=convection+currents&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dconvection%2Bcurrents"><span>By-controlled convection and field-aligned currents near midnight auroral oval for northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Taguchi, S.; Sugiura, M.; Iyemori, T.; Winningham, J. D.; Slavin, J. A.</p> <p>1994-01-01</p> <p>Using the Dynamics Explorer (DE) 2 <span class="hlt">magnetic</span> and electric field and plasma data, B(sub y)- controlled convection and field-aligned currents in the midnight sector for northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) are examined. The results of an analysis of the electric field data show that when IMF is stable and when its magnitude is large, a coherent B(sub y)-controlled convection exists near the midnight auroral oval in the ionosphere having adequate conductivities. When B(sub y) is negative, the convection consists of a westward (eastward) plasma flow at the lower latitudes and an eastward (westward) plasma flow at the higher latitudes in the midnight sector in the northern (southern) ionosphere. When B(sub y) is positive, the flow directions are reversed. The distribution of the field-aligned currents associated with the B(sub y)-controlled convection, in most cases, shows a three-sheet structure. In accordance with the convection the directions of the three sheets are dependent on the sign of B(sub y). The location of disappearance of the precipitating intense electrons having energies of a few keV is close to the convection reversal surface. However, the more detailed relationship between the electron precipitation boundary and the convection reversal surface depends on the case. In some cases the precipitating electrons extend beyond the convection reversal surface, and in others the poleward boundary terminates at a latitude lower than the reversal surface. Previous studies suggest that the poleward boundary of the electrons having energies of a few keV is not necessarily coincident with an open/closed bounary. Thus the open/closed boundary may be at a latitude higher than the poleward boundary of the electron precipitation, or it may be at a latitude lower than the poleward boundary of the electron precipitation. We discuss relationships between the open/closed boundary and the convection reversal surface. When as a possible choice we adopt a view that the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH51A2436T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH51A2436T"><span>Characterizing <span class="hlt">Interplanetary</span> Structures of Long-Lasting Ionospheric Storm Events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tandoi, C.; Dong, Y.; Ngwira, C. M.; Damas, M. C.</p> <p>2015-12-01</p> <p>Geomagnetic storms can result in periods of heightened TEC (Total Electron Content) in Earth's ionosphere. These periods of change in TEC (dTEC) can have adverse impacts on a technological society, such as scintillation of radio signals used by communication and navigation satellites. However, it is unknown which exact properties of a given storm cause dTEC. We are comparing different solar wind properties that result in a significant long-lasting dTEC to see if there are any patterns that remain constant in these storms. These properties, among others, include the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field By and Bz components, the proton density, and the flow speed. As a preliminary investigation, we have studied 15 solar storms. Preliminary results will be presented. In the future, we hope to increase our sample size and analyze over 80 different solar storms, which result in significant dTEC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMSH23A1944B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMSH23A1944B"><span>3-D model of ICME in the <span class="hlt">interplanetary</span> medium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borgazzi, A.; Lara, A.; Niembro, T.</p> <p>2011-12-01</p> <p>We developed a method that describes with simply geometry the coordinates of intersection between the leading edge of an ICME and the position of an arbitrary satellite. When a fast CME is ejected from the Sun to the <span class="hlt">interplanetary</span> space in most of the cases drives a shock. As the CME moves in the corona and later in the <span class="hlt">interplanetary</span> space more material is stacking in the front and edges of the ejecta. In a first approximation, it is possible to assume the shape of these structures, the CME and the stacked material as a cone of revolution, (the ice-cream model [Schwenn et al., (2005)]). The interface may change due to the interaction of the structure and the non-shocked material in front of the ICME but the original shape of a cone of revolution is preserved. We assume, in a three dimensional geometry, an ice-cream cone shape for the ICME and apply an analytical model for its transport in the <span class="hlt">interplanetary</span> medium. The goal of the present method is to give the time and the intersection coordinates between the leading edge of the ICME and any satellite that may be in the path of the ICME. With this information we can modelate the travel of the ICME in the <span class="hlt">interplanetary</span> space using STEREO data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...857...82K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...857...82K"><span><span class="hlt">Interplanetary</span> Type III Bursts and Electron Density Fluctuations in the Solar Wind</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Krupar, V.; Maksimovic, M.; Kontar, E. P.; Zaslavsky, A.; Santolik, O.; Soucek, J.; Kruparova, O.; Eastwood, J. P.; Szabo, A.</p> <p>2018-04-01</p> <p>Type III bursts are generated by fast electron beams originated from <span class="hlt">magnetic</span> reconnection sites of solar flares. As propagation of radio waves in the <span class="hlt">interplanetary</span> medium is strongly affected by random electron density fluctuations, type III bursts provide us with a unique diagnostic tool for solar wind remote plasma measurements. Here, we performed a statistical survey of 152 simple and isolated type III bursts observed by the twin-spacecraft Solar TErrestrial RElations Observatory mission. We investigated their time–frequency profiles in order to retrieve decay times as a function of frequency. Next, we performed Monte Carlo simulations to study the role of scattering due to random electron density fluctuations on time–frequency profiles of radio emissions generated in the <span class="hlt">interplanetary</span> medium. For simplification, we assumed the presence of isotropic electron density fluctuations described by a power law with the Kolmogorov spectral index. Decay times obtained from observations and simulations were compared. We found that the characteristic exponential decay profile of type III bursts can be explained by the scattering of the fundamental component between the source and the observer despite restrictive assumptions included in the Monte Carlo simulation algorithm. Our results suggest that relative electron density fluctuations < δ {n}{{e}}> /{n}{{e}} in the solar wind are 0.06–0.07 over wide range of heliospheric distances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1440491-characteristic-response-whistler-mode-waves-interplanetary-shocks','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1440491-characteristic-response-whistler-mode-waves-interplanetary-shocks"><span>The Characteristic Response of Whistler Mode Waves to <span class="hlt">Interplanetary</span> Shocks</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Yue, Chao; Chen, Lunjin; Bortnik, Jacob; ...</p> <p>2017-09-29</p> <p>Magnetospheric whistler mode waves play a key role in regulating the dynamics of the electron radiation belts. Recent satellite observations indicate a significant influence of <span class="hlt">interplanetary</span> (IP) shocks on whistler mode wave power in the inner magnetosphere. In this study, we statistically investigate the response of whistler mode chorus and plasmaspheric hiss to IP shocks based on Van Allen Probes and THEMIS satellite observations. Immediately after the IP shock arrival, chorus wave power is usually intensified, often at postmidnight to prenoon sector, while plasmaspheric hiss wave power predominantly decreases near the dayside but intensifies near the nightside. We conclude thatmore » chorus wave intensification outside the plasmasphere is probably associated with the suprathermal electron flux enhancement caused by the IP shock. Through a simple ray tracing modeling assuming the scenario that plasmaspheric hiss is originated from chorus, we find that the solar wind dynamic pressure increase changes the <span class="hlt">magnetic</span> field configuration to favor ray penetration in the nightside and promote ray refraction away from the dayside, potentially explaining the <span class="hlt">magnetic</span> local time–dependent responses of plasmaspheric hiss waves following IP shock arrivals.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1440491-characteristic-response-whistler-mode-waves-interplanetary-shocks','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1440491-characteristic-response-whistler-mode-waves-interplanetary-shocks"><span>The Characteristic Response of Whistler Mode Waves to <span class="hlt">Interplanetary</span> Shocks</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Yue, Chao; Chen, Lunjin; Bortnik, Jacob</p> <p></p> <p>Magnetospheric whistler mode waves play a key role in regulating the dynamics of the electron radiation belts. Recent satellite observations indicate a significant influence of <span class="hlt">interplanetary</span> (IP) shocks on whistler mode wave power in the inner magnetosphere. In this study, we statistically investigate the response of whistler mode chorus and plasmaspheric hiss to IP shocks based on Van Allen Probes and THEMIS satellite observations. Immediately after the IP shock arrival, chorus wave power is usually intensified, often at postmidnight to prenoon sector, while plasmaspheric hiss wave power predominantly decreases near the dayside but intensifies near the nightside. We conclude thatmore » chorus wave intensification outside the plasmasphere is probably associated with the suprathermal electron flux enhancement caused by the IP shock. Through a simple ray tracing modeling assuming the scenario that plasmaspheric hiss is originated from chorus, we find that the solar wind dynamic pressure increase changes the <span class="hlt">magnetic</span> field configuration to favor ray penetration in the nightside and promote ray refraction away from the dayside, potentially explaining the <span class="hlt">magnetic</span> local time–dependent responses of plasmaspheric hiss waves following IP shock arrivals.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19720008104','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19720008104"><span>High energy astronomy or astrophysics and properties of the <span class="hlt">interplanetary</span> plasma</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p></p> <p>1971-01-01</p> <p>The research activities related to high energy astrophysics and <span class="hlt">interplanetary</span> plasma are reported. The experimental work in the following areas are described: (1) balloon-and rocket-borne cosmic X-ray, (2) X-ray spectroscopy, and (3) OSO-3 gamma ray experiment. Plasma studies in the <span class="hlt">interplanetary</span> region, magnetosphere, and geomagnetic tail are included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19760061647&hterms=Electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DElectric%2Bcurrent','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19760061647&hterms=Electric+current&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DElectric%2Bcurrent"><span>The generation of <span class="hlt">magnetic</span> fields and electric currents in cometary plasma tails</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ip, W.-H.; Mendis, D. A.</p> <p>1976-01-01</p> <p>Due to the folding of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field into the tail as a comet sweeps through the <span class="hlt">interplanetary</span> medium, the <span class="hlt">magnetic</span> field in the tail can be built up to the order of 100 gammas at a heliocentric distance of about 1 AU. This folding of <span class="hlt">magnetic</span> flux tubes also results in a cross-tail electric current passing through a neutral sheet. When streams of enhanced plasma density merge with the main tail, cross-tail currents as large as 1 billion A may result. A condition could arise which causes a significant fraction of this current to be discharged through the inner coma, resulting in rapid ionization. The typical time scale for such outbursts of ionization is estimated to be of the order of 10,000 sec, which is in reasonable agreement with observation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060029807&hterms=internet&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dinternet','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060029807&hterms=internet&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dinternet"><span>Operating CFDP in the <span class="hlt">Interplanetary</span> Internet</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burleigh, S.</p> <p>2002-01-01</p> <p>This paper examines the design elements of CCSDS File Delivery Protocol and <span class="hlt">Interplanetary</span> Internet technologies that will simplify their integration and discusses the resulting new capabilities, such as efficient transmission of large files via multiple relay satellites operating in parallel.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800011401','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800011401"><span>Coronal <span class="hlt">magnetic</span> structure and the latitude and longitude distribution of energetic particles, 1-5 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Roelof, E. C.; Mitchell, D. G.</p> <p>1979-01-01</p> <p>The relation of the coronal <span class="hlt">magnetic</span> field structure to the distribution of approximately 1 MeV protons in <span class="hlt">interplanetary</span> space between 1 and 5 AU is discussed. After ordering the <span class="hlt">interplanetary</span> data by its estimated coronal emission source location in heliographic coordinates, the multispacecraft measured proton fluxes are compared with coronal <span class="hlt">magnetic</span> field structure infrared as observed in soft X-ray photographs and potential field calculations. Evidence for the propagation and possible acceleration of solar flare protons on high <span class="hlt">magnetic</span> loop structure in the corona is presented. Further, it is shown that corotating proton flux enhancements are associated with regions of low coronal X-ray emission (including coronal holes), usually in association with solar wind stream structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19870025028&hterms=Dd&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DDd','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19870025028&hterms=Dd&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DDd"><span><span class="hlt">Magnetic</span> field directional discontinuities - Characteristics between 0.46 and 1.0 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lepping, R. P.; Behannon, K. W.</p> <p>1986-01-01</p> <p>Based on Mariner 10 data, a statistical survey and an application of the Sonnerup-Cahill variance procedure to a visual identification with 1.2-s <span class="hlt">averages</span> for time intervals corresponding to the equally spaced heliocentric distances of 1.0, 0.72 and 0.46 AU, are employed to study the characteristics of directional discontinuities (DDs) in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. Analysis using two methods demonstrated that the ratio of tangential discontinuities (TDs) to rotational discontinuities (RDs) decreased with decreasing radial distance. Decreases in <span class="hlt">average</span> discontinuity thickness of 41 percent between 1.0 and 0.72 AU, and 56 percent between 1.0 and 0.46 AU, were found for both TDs and RDs, in agreement with Pioneer 10 data between 1 and 5 AU. Normalization of the individual DD thicknesses with respect to the estimated local proton gyroradius (R sub L) gave a nearly constant <span class="hlt">average</span> thickness at the three locations, 36 + or - 5 R sub L, for both RDs and TDs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017SPIE10565E..1GR','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SPIE10565E..1GR"><span>Transceiver optics for <span class="hlt">interplanetary</span> communications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Roberts, W. T.; Farr, W. H.; Rider, B.; Sampath, D.</p> <p>2017-11-01</p> <p>In-situ <span class="hlt">interplanetary</span> science missions constantly push the spacecraft communications systems to support successively higher downlink rates. However, the highly restrictive mass and power constraints placed on <span class="hlt">interplanetary</span> spacecraft significantly limit the desired bandwidth increases in going forward with current radio frequency (RF) technology. To overcome these limitations, we have evaluated the ability of free-space optical communications systems to make substantial gains in downlink bandwidth, while holding to the mass and power limits allocated to current state-of-the-art Ka-band communications systems. A primary component of such an optical communications system is the optical assembly, comprised of the optical support structure, optical elements, baffles and outer enclosure. We wish to estimate the total mass that such an optical assembly might require, and assess what form it might take. Finally, to ground this generalized study, we should produce a conceptual design, and use that to verify its ability to achieve the required downlink gain, estimate it's specific optical and opto-mechanical requirements, and evaluate the feasibility of producing the assembly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890056998&hterms=tins&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtins','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890056998&hterms=tins&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtins"><span>Tin in a chondritic <span class="hlt">interplanetary</span> dust particle</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rietmeijer, Frans J. M.</p> <p>1989-01-01</p> <p>Submicron platey Sn-rich grains are present in chondritic porous <span class="hlt">interplanetary</span> dust particle (IDP) W7029 A and it is the second occurrence of a tin mineral in a stratospheric micrometeorite. Selected Area Electron Diffraction data for the Sn-rich grains match with Sn2O3 and Sn3O4. The oxide(s) may have formed in the solar nebula when tin metal catalytically supported reduction of CO or during flash heating on atmospheric entry of the IDP. The presence of tin is consistent with enrichments for other volatile trace elements in chondritic IDPs and may signal an emerging trend toward nonchondritic volatile element abundances in chondritic IDPs. The observation confirms small-scale mineralogical heterogeneity in fine-grained chondritic porous <span class="hlt">interplanetary</span> dust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19880001327','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19880001327"><span>STIP Symposium on Physical Interpretation of Solar/<span class="hlt">Interplanetary</span> and Cometary Intervals</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, S. T.</p> <p>1987-01-01</p> <p>The study of travelling <span class="hlt">interplanetary</span> phenomena has continued over a period of years. The STIP (Study of Travelling <span class="hlt">Interplanetary</span> Phenomena) Symposium on Physical Interpretation of Solar/<span class="hlt">Interplanetary</span> and Cometary Intervals was held in Huntsville, Alabama, on May 12-15, 1987, the first of these meetings to be held in the United States. The Symposium's objective was to coordinate and disseminate new science gained from the recent solar-terrestrial and cometary intervals which can be used to better understand the linkage of physical events to the Sun's vagaries (flares, coronal holes, eruptive prominences) from their initial detection to their consequence. Fifty-one presentations were made during the four-day period. Abstracts of these reports are included as Appendix A.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750004795','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750004795"><span>On the use of Godhavn H-component as an indicator of the <span class="hlt">interplanetary</span> sector polarity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Svalgaard, L.</p> <p>1974-01-01</p> <p>An objective method of inferring the polarity of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field using the H-component at Godhavn is presented. The objectively inferred polarities are compared with a subjective index inferred earlier. It is concluded that no significant difference exists between the two methods. The inferred polarities derived from Godhavn H is biased by the (slp) sub q signature in the sense that during summer prolonged intervals of geomagnetic calm will result in inferred Away polarity regardless of the actual sector polarity. This bias does not significantly alter the large scale structure of the inferred sector structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22667482-redefining-boundaries-interplanetary-coronal-mass-ejections-from-observations-ecliptic-plane','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22667482-redefining-boundaries-interplanetary-coronal-mass-ejections-from-observations-ecliptic-plane"><span>REDEFINING THE BOUNDARIES OF <span class="hlt">INTERPLANETARY</span> CORONAL MASS EJECTIONS FROM OBSERVATIONS AT THE ECLIPTIC PLANE</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Cid, C.; Palacios, J.; Saiz, E.</p> <p>2016-09-01</p> <p>On 2015 January 6–7, an <span class="hlt">interplanetary</span> coronal mass ejection (ICME) was observed at L1. This event, which can be associated with a weak and slow coronal mass ejection, allows us to discuss the differences between the boundaries of the <span class="hlt">magnetic</span> cloud and the compositional boundaries. A fast stream from a solar coronal hole surrounding this ICME offers a unique opportunity to check the boundaries’ process definition and to explain differences between them. Using Wind and ACE data, we perform a complementary analysis involving compositional, <span class="hlt">magnetic</span>, and kinematic observations providing relevant information regarding the evolution of the ICME as travelling awaymore » from the Sun. We propose erosion, at least at the front boundary of the ICME, as the main reason for the difference between the boundaries, and compositional signatures as the most precise diagnostic tool for the boundaries of ICMEs.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810016495&hterms=magnetic+vector+potential&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmagnetic%2Bvector%2Bpotential','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810016495&hterms=magnetic+vector+potential&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dmagnetic%2Bvector%2Bpotential"><span>Determination of <span class="hlt">magnetic</span> helicity in the solar wind and implications for cosmic ray propagation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Matthaeus, W. H.; Goldstein, M. L.</p> <p>1981-01-01</p> <p>The mean value of the correlation between local <span class="hlt">magnetic</span> field and vector potential, known as the <span class="hlt">magnetic</span> helicity, is a measure of the lack of mirror reflection symmetry of <span class="hlt">magnetic</span> covariances in a turbulent medium. A method is presented for extraction of helicity spectra from magnetometer data, and applied to an evaluation of the <span class="hlt">magnetic</span> helicity of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fluctuations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...858..123H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...858..123H"><span><span class="hlt">Interplanetary</span> Shocks Inducing Magnetospheric Supersubstorms (SML < ‑2500 nT): Unusual Auroral Morphologies and Energy Flow</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hajra, Rajkumar; Tsurutani, Bruce T.</p> <p>2018-05-01</p> <p>We present case studies of two <span class="hlt">interplanetary</span> shock-induced supersubstorms (SSSs) with extremely high intensities (peak SML ‑4418 and ‑2668 nT) and long durations (∼1.7 and ∼3.1 hr). The events occurred on 2005 January 21 and 2010 April 5, respectively. It is shown that these SSSs have a different auroral evolution than a nominal Akasofu-type substorm. The auroras associated with the SSSs did not have the standard midnight onset and following expansion. Instead, at the time of the SML index peak, the midnight sector was generally devoid of intense auroras, while the most intense auroras were located in the premidnight and postmidnight <span class="hlt">magnetic</span> local times. Precursor energy input through <span class="hlt">magnetic</span> reconnection was insufficient to balance the large ionospheric energy dissipation during the SSSs. It is argued that besides the release of stored magnetotail energy during the SSSs, these were powered by additional direct driving through both dayside <span class="hlt">magnetic</span> reconnection and solar wind ram energy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950006593','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950006593"><span>A <span class="hlt">magnetic</span> shield/dual purpose mission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Watkins, Seth; Albertelli, Jamil; Copeland, R. Braden; Correll, Eric; Dales, Chris; Davis, Dana; Davis, Nechole; Duck, Rob; Feaster, Sandi; Grant, Patrick</p> <p>1994-01-01</p> <p>The objective of this work is to design, build, and fly a dual-purpose payload whose function is to produce a large volume, low intensity <span class="hlt">magnetic</span> field and to test the concept of using such a <span class="hlt">magnetic</span> field to protect manned spacecraft against particle radiation. An additional mission objective is to study the effect of this moving field on upper atmosphere plasmas. Both mission objectives appear to be capable of being tested using the same superconducting coil. The potential benefits of this <span class="hlt">magnetic</span> shield concept apply directly to both earth-orbital and <span class="hlt">interplanetary</span> missions. This payload would be a first step in assessing the true potential of large volume <span class="hlt">magnetic</span> fields in the U.S. space program. Either converted launch systems or piggyback payload opportunities may be appropriate for this mission. The use of superconducting coils for <span class="hlt">magnetic</span> shielding against solar flare radiation during manned <span class="hlt">interplanetary</span> missions has long been contemplated and was considered in detail in the years preceding the Apollo mission. With the advent of new superconductors, it has now become realistic to reconsider this concept for a Mars mission. Even in near-earth orbits, large volume <span class="hlt">magnetic</span> fields produced using conventional metallic superconductors allow novel plasma physics experiments to be contemplated. Both deployed field-coil and non-deployed field-coil shielding arrangements have been investigated, with the latter being most suitable for an initial test payload in a polar orbit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1992AIPC..246..130G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1992AIPC..246..130G"><span>Integrated shielding systems for manned <span class="hlt">interplanetary</span> spaceflight</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>George, Jeffrey A.</p> <p>1992-01-01</p> <p>The radiation environment encountered by manned <span class="hlt">interplanetary</span> missions can have a severe impact on both vehicle design and mission performance. This study investigates the potential impact of radiation protection on <span class="hlt">interplanetary</span> vehicle design for a manned Mars mission. A systems approach was used to investigate the radiation protection requirements of the sum <span class="hlt">interplanetary</span> environment. Radiation budgets were developed which result in minimum integrated shielding system masses for both nuclear and non-nuclear powered missions. A variety of system configurations and geometries were assessed over a range of dose constraints. For an annual dose equivalent rate limit of 50 rem/yr, an environmental shielding system composed of a habitat shield and storm shelter was found to result in the lowest total mass. For a limit of 65 rem/yr, a system composed of a sleeping quarters shield was least massive, and resulted in significantly reduced system mass. At a limit of 75 rem/yr, a storm shelter alone was found to be sufficient, and exhibited a further mass reduction. Optimal shielding system results for 10 MWe nuclear powered missions were found to follow along similar lines, with the addition of a reactor shadow shield. A solar minimum galactic cosmic ray spectrum and one anomalously large solar particle event during the course of a two year mission were assumed. Water was assumed for environmental radiation shielding.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMSH51A2575B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMSH51A2575B"><span><span class="hlt">Average</span> <span class="hlt">Magnetic</span> Field Magnitude Profiles of Wind <span class="hlt">Magnetic</span> Clouds as a Function of Closest Approach to the Clouds' Axes and Comparison to Model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berdichevsky, D. B.; Lepping, R. P.; Wu, C. C.</p> <p>2016-12-01</p> <p>We examine the <span class="hlt">average</span> <span class="hlt">magnetic</span> field magnitude (|B|) within <span class="hlt">magnetic</span> clouds (MCs) observed over the period of 1995 to July of 2015, to understand the difference between this field magnitude and the ideal (field magnitude) |B|-profiles expected from using a static, constant-α, force-free, cylindrically symmetric model for MCs (Lepping et al. 1990, denoted as the LJB model here) in general. We classify all MCs according to an objectively assigned quality, Qo (=1,2,3, for excellent, good, and poor). There are a total of 209 MCs and 124 if only Qo=1,2 cases are considered. <span class="hlt">Average</span> normalized field with respect to closest approach (CA) is stressed where we separate cases into four CA sectors centered at 12.5%, 37.5%, 62.5%, and 87.5% of the <span class="hlt">average</span> radius; the <span class="hlt">averaging</span> is done on a percent-duration basis to put all cases on the same footing. By normalized field we mean that, before <span class="hlt">averaging</span>, the |B| for each MC at each point is divided by the field magnitude estimated for the MC's axis (Bo) as determined by the LJB model. The actual <span class="hlt">averages</span> for the 209 and 124 MC sets are compared separately to the LJB model, after an adjustment for MC expansion, which is estimated from long-term <span class="hlt">average</span> conditions of MCs at 1 AU using a typical speed difference of 40 km/s across the <span class="hlt">average</span> MC. The <B/Bo> comparison is a direct difference (<span class="hlt">average</span> observations - model) vs. time for the four sets separately. These four difference-relationships are fitted with four quadratic curves, which have very small sigmas for the fits. Interpretation of these relationships (called Quad formulae) should provide a comprehensive view of the variation of the normalized field-magnitude throughout the <span class="hlt">average</span> MC where we expect both front and rear compression (due to solar wind interaction) to be part of its explanation. These formulae are also being considered for modifying the LJB model. This modification is expected to be used for assistance in a scheme used for forecasting the timing and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH53A2555H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH53A2555H"><span>Dependence of the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field on Heliocentric Distance between 0.3 and 1.7 AU from MESSENGER, ACE and MAVEN data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hanneson, C.; Johnson, C.; Al Asad, M.</p> <p>2017-12-01</p> <p>Magnetometer data from the MErcury Surface, Space ENvironment, GEochemistry and Ranging (MESSENGER), Advanced Composition Explorer (ACE) and Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft were used to characterize the variation of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) with heliocentric distance from 0.3 to 1.7 AU. MESSENGER and ACE data form a set of simultaneous observations that spans eight years, from March 2007 until April 2015, with ACE observations continuing until the present. MAVEN data have been collected since November 2014. Furthermore, for the period 2008-2015, MESSENGER and ACE observations were taken over the same range of heliocentric distances: 0.31-0.47 AU and 0.94-1.00 AU respectively. The IMF varies with the solar sunspot cycle, and so data taken simultaneously at different heliocentric distances allow solar-cycle effects to be decoupled from the radial evolution of the IMF. The data were <span class="hlt">averaged</span> temporally by taking 1-hour means, and median values were then computed in 0.01-AU bins. For the time interval spanned by all observations, the median value of the magnitude of the IMF decreases steadily from 30.1 nT at 0.3 AU to 4.3 nT at 1.0 AU and 2.5 nT at 1.6 AU. The magnitude of the IMF was found to decay with heliocentric distance according to an inverse power law with an exponent equal to the adiabatic index for an ideal monatomic gas, 5/3, within 95% confidence limits. The magnitude of the radial component decays with distance as an inverse square law within 95% confidence limits. We also consider temporal variations of the heliocentric-dependence of the IMF over the current solar cycle by computing power law fits to the simultaneous MESSENGER and ACE observations using a moving window. Our study complements the recent study of Gruesbeck et al. (2017) that used Juno data to consider the variation in IMF properties over the heliocentric distance range 1 to 6 AU.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E2108Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E2108Y"><span>Large-scale solar wind streams: <span class="hlt">Average</span> temporal evolution of parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yermolaev, Yuri; Lodkina, Irina; Yermolaev, Michael; Nikolaeva, Nadezhda</p> <p>2016-07-01</p> <p>In the report we describe the <span class="hlt">average</span> temporal profiles of plasma and field parameters in the disturbed large-scale types of solar wind (SW): corotating interaction regions (CIR), <span class="hlt">interplanetary</span> coronal mass ejections (ICME) (both <span class="hlt">magnetic</span> cloud (MC) and Ejecta), and Sheath as well as the <span class="hlt">interplanetary</span> shock (IS) on the basis of OMNI database and our Catalog of large-scale solar wind phenomena during 1976-2000 (see website ftp://ftp.iki.rssi.ru/pub/omni/ and paper [Yermolaev et al., 2009]). To consider influence of both the surrounding undisturbed solar wind, and the interaction of the disturbed types of the solar wind on the parameters, we separately analyze the following sequences of the phenomena: (1) SW/CIR/SW, (2) SW/IS/CIR/SW, (3) SW/Ejecta/SW, (4) SW/Sheath/Ejecta/SW, (5) SW/IS/Sheath/Ejecta/SW, (6) SW/MC/SW, (7) SW/Sheath/MC/SW, and (8) SW/IS/Sheath/MC/SW. To take into account the different durations of SW types, we use the double superposed epoch analysis (DSEA) method: rescaling the duration of the interval for all types in such a manner that, respectively, beginning and end for all intervals of selected type coincide [Yermolaev et al., 2010; 2015]. Obtained data allow us to suggest that (1) the behavior of parameters in Sheath and in CIR is very similar not only qualitatively but also quantitatively, and (2) the speed angle phi in ICME changes from 2 to -2deg. while in CIR and Sheath it changes from -2 to 2 deg., i.e., the streams in CIR/Sheath and ICME deviate in the opposite side. The work was supported by the Russian Foundation for Basic Research, project 16-02-00125 and by Program of Presidium of the Russian Academy of Sciences. References: Yermolaev, Yu. I., N. S. Nikolaeva, I. G. Lodkina, and M. Yu. Yermolaev (2009), Catalog of Large-Scale Solar Wind Phenomena during 1976-2000, Cosmic Research, , Vol. 47, No. 2, pp. 81-94. Yermolaev, Y. I., N. S. Nikolaeva, I. G. Lodkina, and M. Y. Yermolaev (2010), Specific <span class="hlt">interplanetary</span> conditions for CIR</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH41B2778G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH41B2778G"><span>The Acceleration of Thermal Protons and Minor Ions at a Quasi-Parallel <span class="hlt">Interplanetary</span> Shock</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Giacalone, J.; Lario, D.; Lepri, S. T.</p> <p>2017-12-01</p> <p>We compare the results from self-consistent hybrid simulations (kinetic ions, massless fluid electrons) and spacecraft observations of a strong, quasi-parallel <span class="hlt">interplanetary</span> shock that crossed the Advanced Composition Explorer (ACE) on DOY 94, 2001. In our simulations, the un-shocked plasma-frame ion distributions are Maxwellian. Our simulations include protons and minor ions (alphas, 3He++, and C5+). The <span class="hlt">interplanetary</span> shock crossed both the ACE and the Wind spacecraft, and was associated with significant increases in the flux of > 50 keV/nuc ions. Our simulation uses parameters (ion densities, <span class="hlt">magnetic</span> field strength, Mach number, etc.) consistent with those observed. Acceleration of the ions by the shock, in a manner similar to that expected from diffusive shock acceleration theory, leads to a high-energy tail in the distribution of the post-shock plasma for all ions we considered. The simulated distributions are directly compared to those observed by ACE/SWICS, EPAM, and ULEIS, and Wind/STICS and 3DP, covering the energy range from below the thermal peak to the suprathermal tail. We conclude from our study that the solar wind is the most significant source of the high-energy ions for this event. Our results have important implications for the physics of the so-called `injection problem', which will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E1986M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E1986M"><span>Dusty Plasma Effects in the <span class="hlt">Interplanetary</span> Medium?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mann, Ingrid; Issautier, Karine; Meyer-Vernet, Nicole; Le Chat, Gaétan; Czechowski, Andrzej; Zaslavsky, Arnaud; Zouganelis, Yannis; Belheouane, Soraya</p> <p></p> <p>Cosmic dust particles exist in a variety of compositions and sizes in the <span class="hlt">interplanetary</span> medium. There is little direct information on the composition, but those <span class="hlt">interplanetary</span> dust particles that are collected in the upper Earth’s atmosphere and can be studied in the laboratory typically have an irregular, sometimes porous structure on scales <100 nm. They contain magnesium-rich silicates and silicon carbide, iron-nickel and iron-sulfur compounds, calcium- and aluminum oxides, and chemical compounds that contain a large mass fraction of carbon (e.g. carbonaceous species). A fraction of the dust originates from comets, but because of their bulk material temperature of about 280 K near 1 AU, most icy compounds have disappeared. The dust particles are embedded in the solar wind, a hot plasma with at 1 AU kinetic temperatures around 100 000 K and flow direction nearly radial outward from the Sun at supersonic bulk velocities around 400 km/s. Since the dust particles carry an electric surface charge they are subject to electromagnetic forces and the nanodust particles are efficiently accelerated to velocities of order of solar wind speed. The acceleration of the nanodust is similar, but not identical to the formation of pick-up ions. The S/WAVES radio wave instrument on STEREO measured a flux of nanodust at 1 AU [1]. The nanodust probably forms in the region inward of 1 AU and is accelerated by the solar wind as discussed. We also discuss the different paths of dust - plasma interactions in the <span class="hlt">interplanetary</span> medium and their observations with space experiments. Comparing these interactions we show that the <span class="hlt">interplanetary</span> medium near 1 AU can in many cases be described as “dust in plasma" rather than "dusty plasma”. [1] S. Belheouane, N. Meyer-Vernet, K. Issautier, G. Le Chat, A. Zaslavsky, Y. Zouganelis, I. Mann, A. Czechowski: Dynamics of nanoparticles detected at 1 AU by S/WAVES onboard STEREO spacecraft, in this session.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920054191&hterms=topology&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dtopology','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920054191&hterms=topology&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dtopology"><span>Energetic ion observations in the <span class="hlt">magnetic</span> cloud of 14-15 January 1988 and their implications for the <span class="hlt">magnetic</span> field topology</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Farrugia, C. J.; Burlaga, L. F.</p> <p>1991-01-01</p> <p>On 14-15 January 1988, a <span class="hlt">magnetic</span> cloud with a local field topology consistent with an east-west aligned cylindrical flux-rope and which formed the driver of an <span class="hlt">interplanetary</span> shock passed the earth. Using 0.5-4 MeV/n ion data from the instrument on IMP 8, the paper addresses the question of whether or not <span class="hlt">magnetic</span> field lines within the <span class="hlt">magnetic</span> cloud were connected to the sun. An impulsive solar particle event was detected inside the <span class="hlt">magnetic</span> cloud strongly suggesting that the field lines were rooted at the sun.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PMB....63c5003H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PMB....63c5003H"><span><span class="hlt">Averaged</span> head phantoms from <span class="hlt">magnetic</span> resonance images of Korean children and young adults</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Han, Miran; Lee, Ae-Kyoung; Choi, Hyung-Do; Jung, Yong Wook; Park, Jin Seo</p> <p>2018-02-01</p> <p>Increased use of mobile phones raises concerns about the health risks of electromagnetic radiation. Phantom heads are routinely used for radiofrequency dosimetry simulations, and the purpose of this study was to construct <span class="hlt">averaged</span> phantom heads for children and young adults. Using <span class="hlt">magnetic</span> resonance images (MRI), sectioned cadaver images, and a hybrid approach, we initially built template phantoms representing 6-, 9-, 12-, 15-year-old children and young adults. Our subsequent approach revised the template phantoms using 29 <span class="hlt">averaged</span> items that were identified by <span class="hlt">averaging</span> the MRI data from 500 children and young adults. In females, the brain size and cranium thickness peaked in the early teens and then decreased. This is contrary to what was observed in males, where brain size and cranium thicknesses either plateaued or grew continuously. The overall shape of brains was spherical in children and became ellipsoidal by adulthood. In this study, we devised a method to build <span class="hlt">averaged</span> phantom heads by constructing surface and voxel models. The surface model could be used for phantom manipulation, whereas the voxel model could be used for compliance test of specific absorption rate (SAR) for users of mobile phones or other electronic devices.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018LPICo2063.3013T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018LPICo2063.3013T"><span>Testing Fundamental Gravity with <span class="hlt">Interplanetary</span> Laser Ranging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Turyshev, S. G.; Shao, M.; Hahn, I.</p> <p>2018-02-01</p> <p>Very accurate range measurements with the <span class="hlt">Interplanetary</span> Laser Ranging Terminal (ILRT) will push high-precision tests of astrophysics/gravitation into a new regime. It could be used for navigation and investigations in planetary/lunar science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002cosp...34E.625V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002cosp...34E.625V"><span>Real-time <span class="hlt">Interplanetary</span> Shock Prediciton System</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vandegriff, J.; Ho, G.; Plauger, J.</p> <p></p> <p>A system is being developed to predict the arrival times and maximum intensities of energetic storm particle (ESP) events at the earth. Measurements of particle flux values at L1 being made by the Electron, Proton, and Alpha Monitor (EPAM) instrument aboard NASA's ACE spacecraft are made available in real-time by the NOAA Space Environment Center as 5 minute <span class="hlt">averages</span> of several proton and electron energy channels. Past EPAM flux measurements can be used to train forecasting algorithms which then run on the real-time data. Up to 3 days before the arrival of the <span class="hlt">interplanetary</span> shock associated with an ESP event, characteristic changes in the particle intensities (such as decreased spectral slope and increased overall flux level) are easily discernable. Once the onset of an event is detected, a neural net is used to forecast the arrival time and flux level for the event. We present results obtained with this technique for forecasting the largest of the ESP events detected by EPAM. Forecasting information will be made publicly available through http://sd-www.jhuapl.edu/ACE/EPAM/, the Johns Hopkins University Applied Physics Lab web site for the ACE/EPAM instrument.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140011510','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140011510"><span>Design of the VISITOR Tool: A Versatile ImpulSive <span class="hlt">Interplanetary</span> Trajectory OptimizeR</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Corpaccioli, Luca; Linskens, Harry; Komar, David R.</p> <p>2014-01-01</p> <p>The design of trajectories for <span class="hlt">interplanetary</span> missions represents one of the most complex and important problems to solve during conceptual space mission design. To facilitate conceptual mission sizing activities, it is essential to obtain sufficiently accurate trajectories in a fast and repeatable manner. To this end, the VISITOR tool was developed. This tool modularly augments a patched conic MGA-1DSM model with a mass model, launch window analysis, and the ability to simulate more realistic arrival and departure operations. This was implemented in MATLAB, exploiting the built-in optimization tools and vector analysis routines. The chosen optimization strategy uses a grid search and pattern search, an iterative variable grid method. A genetic algorithm can be selectively used to improve search space pruning, at the cost of losing the repeatability of the results and increased computation time. The tool was validated against seven flown missions: the <span class="hlt">average</span> total mission (Delta)V offset from the nominal trajectory was 9.1%, which was reduced to 7.3% when using the genetic algorithm at the cost of an increase in computation time by a factor 5.7. It was found that VISITOR was well-suited for the conceptual design of <span class="hlt">interplanetary</span> trajectories, while also facilitating future improvements due to its modular structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH51E..06A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH51E..06A"><span>A Study of the <span class="hlt">Interplanetary</span> Signatures of Earth-Arriving CMEs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akiyama, S.; Yashiro, S.; Gopalswamy, N.; Xie, H.; Makela, P. A.; Kay, C.</p> <p>2017-12-01</p> <p>We studied <span class="hlt">interplanetary</span> (IP) signatures associated with coronal mass ejections (CMEs) that are likely to reach Earth. In order to find Earth- arriving CMEs, we started with disk-center CMEs originating within 30 degrees from the central meridian and the equator. Using the side-view images from the STEREO mission, we excluded CMEs that faded out before reaching the Earth orbit, or were captured by other CMEs, or erupted away from the ecliptic plane. We found 61 Earth- arriving CMEs during 2009/10/01 - 2012/07/31 (inclusive). Though all events were observed to reach Earth in the STEREO/HI2 field of view, only 34 out of 61 events (56%) were associated with <span class="hlt">magnetic</span> cloud (MC) or ejecta (EJ) observed by ACE or Wind. We compared the CME characteristics associated with 9 MCs, 25 EJs, and 27 no- clear- signature (NCS) events to find out what might cause the difference in the IP signatures. To avoid projection effects, we used coronagraph images obtained by the STEREO mission. The <span class="hlt">average</span> speed (width) of CMEs associated with MCs, EJs, and NCSs are 484 km/s (104°), 663 km/s (135°), and 595 km/s (144°), respectively. CMEs associated with MCs tend to be less energetic than other types in our dataset. We also checked the coronal holes (CHs) near the CME source to examine the effect of the CME deflection. In the case of MCs and EJs, only 22% (2/9) and 28% (7/25) events have CHs near the source, while 48% (13/27) NCS events have nearby CHs. We discuss what factors near the Sun cause the observed differences at Earth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH41F..08F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH41F..08F"><span>Extreme <span class="hlt">Magnetic</span> Storms: Their Characteristics and Possible Consequences for Humanity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Falkowski, B. J.; Tsurutani, B.; Lakhina, G. S.; Deng, Y.; Mannucci, A. J.</p> <p>2015-12-01</p> <p>The solar and <span class="hlt">interplanetary</span> conditions necessary to create an extreme <span class="hlt">magnetic</span> storm will be discussed. The Carrington 1859 event was not the largest possible. It will be shown that different facets of fast ICMEs/extreme <span class="hlt">magnetic</span> storms will have different limitations. Some possible adverse effects of such extreme space weather events on society will be addressed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820033674&hterms=monsanto&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmonsanto','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820033674&hterms=monsanto&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmonsanto"><span>Infrared spectroscopy of <span class="hlt">interplanetary</span> dust in the laboratory</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fraundorf, P.; Patel, R. I.; Freeman, J. J.</p> <p>1981-01-01</p> <p>A mount containing three crushed chondritic <span class="hlt">interplanetary</span> dust particles (IDPs) collected in the earth's stratosphere and subjected to infrared spectroscopic measurements shows features near 1000 and 500/cm, suggesting crystalline pyroxene rather than crystalline olivine, amorphous olivine, or meteoritic clay minerals. Chondritic IDP structural diversity and atmospheric heating effects must be considered when comparing this spectrum with <span class="hlt">interplanetary</span> and cometary dust astrophysical spectra. TEM and infrared observations of one member of the rare subset of IDPs resembling hydrated carbonaceous chondrite matrix material shows a close infrared spectrum resemblance between 4000 and 400/cm to the C2 meteorite Murchison. TEM observations suggest that this class of particles may be used as an atmospheric entry heating-process thermometer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26437746','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26437746"><span>The role of size polydispersity in <span class="hlt">magnetic</span> fluid hyperthermia: <span class="hlt">average</span> vs. local infra/over-heating effects.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Munoz-Menendez, Cristina; Conde-Leboran, Ivan; Baldomir, Daniel; Chubykalo-Fesenko, Oksana; Serantes, David</p> <p>2015-11-07</p> <p>An efficient and safe hyperthermia cancer treatment requires the accurate control of the heating performance of <span class="hlt">magnetic</span> nanoparticles, which is directly related to their size. However, in any particle system the existence of some size polydispersity is experimentally unavoidable, which results in a different local heating output and consequently a different hyperthermia performance depending on the size of each particle. With the aim to shed some light on this significant issue, we have used a Monte Carlo technique to study the role of size polydispersity in heat dissipation at both the local (single particle) and global (macroscopic <span class="hlt">average</span>) levels. We have systematically varied size polydispersity, temperature and interparticle dipolar interaction conditions, and evaluated local heating as a function of these parameters. Our results provide a simple guide on how to choose, for a given polydispersity degree, the more adequate <span class="hlt">average</span> particle size so that the local variation in the released heat is kept within some limits that correspond to safety boundaries for the <span class="hlt">average</span>-system hyperthermia performance. All together we believe that our results may help in the design of more effective <span class="hlt">magnetic</span> hyperthermia applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950056920&hterms=Magnetic+Flux&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DMagnetic%2BFlux','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950056920&hterms=Magnetic+Flux&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DMagnetic%2BFlux"><span><span class="hlt">Magnetic</span> flux ropes at the high-latitude magnetopause</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Berchem, Jean; Raeder, Joachim; Ashour-Abdalla, Maha</p> <p>1995-01-01</p> <p>We examine the consequences of <span class="hlt">magnetic</span> reconnection at the high-latitude magnetopause using a three-dimensional global magnetohydrodynamic simulation of the solar wind interaction with the Earth's magnetosphere. <span class="hlt">Magnetic</span> field lines from the simulation reveal the formation of <span class="hlt">magnetic</span> flux ropes during periods with northward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field. These flux ropes result from multiple reconnection processes between the lobes field lines and draped magnetosheath field lines that are convected around the flank of the magnetosphere. The flux ropes identified in the simulation are consistent with features observed in the <span class="hlt">magnetic</span> field measured by Hawkeye-1 during some high-latitude magnetopause crossings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990RMxAA..21..541C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990RMxAA..21..541C"><span>Nonthermal Radiation Processes in <span class="hlt">Interplanetary</span> Plasmas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chian, A. C. L.</p> <p>1990-11-01</p> <p>RESUMEN. En la interacci6n de haces de electrones energeticos con plasmas interplanetarios, se excitan ondas intensas de Langmuir debido a inestabilidad del haz de plasma. Las ondas Langmuir a su vez interaccio nan con fluctuaciones de densidad de baja frecuencia para producir radiaciones. Si la longitud de las ondas de Langmujr exceden las condicio nes del umbral, se puede efectuar la conversi5n de modo no lineal a on- das electromagneticas a traves de inestabilidades parametricas. As se puede excitar en un plasma inestabilidades parametricas electromagneticas impulsadas por ondas intensas de Langmuir: (1) inestabilidades de decaimiento/fusi5n electromagnetica impulsadas por una bomba de Lang- muir que viaja; (2) inestabilidades dobles electromagneticas de decai- miento/fusi5n impulsadas por dos bombas de Langrnuir directamente opues- tas; y (3) inestabilidades de dos corrientes oscilatorias electromagne- ticas impulsadas por dos bombas de Langmuir de corrientes contrarias. Se concluye que las inestabilidades parametricas electromagneticas in- ducidas por las ondas de Langmuir son las fuentes posibles de radiacio- nes no termicas en plasmas interplanetarios. ABSTRACT: Nonthermal radio emissions near the local electron plasma frequency have been detected in various regions of <span class="hlt">interplanetary</span> plasmas: solar wind, upstream of planetary bow shock, and heliopause. Energetic electron beams accelerated by solar flares, planetary bow shocks, and the terminal shock of heliosphere provide the energy source for these radio emissions. Thus, it is expected that similar nonthermal radiation processes may be responsible for the generation of these radio emissions. As energetic electron beams interact with <span class="hlt">interplanetary</span> plasmas, intense Langmuir waves are excited due to a beam-plasma instability. The Langmuir waves then interact with low-frequency density fluctuations to produce radiations near the local electron plasma frequency. If Langmuir waves are of sufficiently large</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002iaf..confE.700B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002iaf..confE.700B"><span>The <span class="hlt">Interplanetary</span> Internet: A Communications Infrastructure for Mars Exploration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burleigh, S.; Cerf, V.; Durst, R.; Fall, K.; Hooke, A.; Scott, K.; Weiss, H.</p> <p>2002-01-01</p> <p>A successful program of Mars Exploration will depend heavily on a robust and dependable space communications infrastructure that is well integrated with the terrestrial Internet. In the same way that the underpinnings of the Internet are the standardized "TCP/IP" suite of protocols, an "<span class="hlt">Interplanetary</span> Internet" will need a similar set of capabilities that can support reliable communications across vast distances and highly stressed communications environments. For the past twenty years, the Consultative Committee for Space Data Systems (CCSDS) has been developing standardized long- haul space link communications techniques that are now in use by over two hundred missions within the international space community. New CCSDS developments, shortly to be infused into Mars missions, include a proximity link standard and a store-and- forward file transfer protocol. As part of its `Next Generation Internet' initiative, the U.S. Defense Advanced Projects Agency (DARPA) recently supported an architectural study of a future "<span class="hlt">InterPlaNetary</span> Internet" (IPN). The IPN architecture assumes that in short-delay environments - such as on and around Mars - standard Internet technologies will be adapted to the locally harsh environment and deployed within surface vehicles and orbiting relays. A long-haul <span class="hlt">interplanetary</span> backbone network that includes Deep Space Network (DSN) gateways into the terrestrial Internet will interconnect these distributed internets that are scattered across the Solar System. Just as TCP/IP unites the Earth's "network of networks" to become the Internet, a new suite of protocols known as "Bundling" will enable the IPN to become a "network of internets" to support true <span class="hlt">interplanetary</span> dialog. An <span class="hlt">InterPlaNetary</span> Internet Research Group has been established within the Internet community to coordinate this research and NASA has begun to support the further development of the IPN architecture and the Bundling protocols. A strategy is being developed whereby the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11542670','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11542670"><span>The problems of cosmic ray particle simulation for the near-Earth orbital and <span class="hlt">interplanetary</span> flight conditions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nymmik, R A</p> <p>1999-10-01</p> <p>A wide range of the galactic cosmic ray and SEP event flux simulation problems for the near-Earth satellite and manned spacecraft orbits and for the <span class="hlt">interplanetary</span> mission trajectories are discussed. The models of the galactic cosmic ray and SEP events in the Earth orbit beyond the Earth's magnetosphere are used as a basis. The particle fluxes in the near-Earth orbits should be calculated using the transmission functions. To calculate the functions, the dependences of the cutoff rigidities on the <span class="hlt">magnetic</span> disturbance level and on <span class="hlt">magnetic</span> local time have to be known. In the case of space flights towards the Sun and to the boundary of the solar system, particular attention is paid to the changes in the SEP event occurrence frequency and size. The particle flux gradients are applied in this case to galactic cosmic ray fluxes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989ommd.proc..191S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989ommd.proc..191S"><span>Earth orbital operations supporting manned <span class="hlt">interplanetary</span> missions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sherwood, Brent; Buddington, Patricia A.; Whittaker, William L.</p> <p></p> <p>The orbital operations required to accumulate, assemble, test, verify, maintain, and launch complex manned space systems on <span class="hlt">interplanetary</span> missions from earth orbit are as vital as the flight hardware itself. Vast numbers of orbital crew are neither necessary nor desirable for accomplishing the required tasks. A suite of robotic techniques under human supervisory control, relying on sensors, software and manipulators either currently emergent or already applied in terrestrial settings, can make the job tractable. The mission vehicle becomes largely self-assembling, using its own rigid aerobrake as a work platform. The Space Station, having been used as a laboratory testbed and to house an assembly crew of four, is not dominated by the process. A feasible development schedule, if begun soon, could emplace orbital support technologies for exploration missions in time for a 2004 first <span class="hlt">interplanetary</span> launch.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900056445&hterms=Whittaker&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3DWhittaker','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900056445&hterms=Whittaker&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAuthor-Name%26N%3D0%26No%3D20%26Ntt%3DWhittaker"><span>Earth orbital operations supporting manned <span class="hlt">interplanetary</span> missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sherwood, Brent; Buddington, Patricia A.; Whittaker, William L.</p> <p>1989-01-01</p> <p>The orbital operations required to accumulate, assemble, test, verify, maintain, and launch complex manned space systems on <span class="hlt">interplanetary</span> missions from earth orbit are as vital as the flight hardware itself. Vast numbers of orbital crew are neither necessary nor desirable for accomplishing the required tasks. A suite of robotic techniques under human supervisory control, relying on sensors, software and manipulators either currently emergent or already applied in terrestrial settings, can make the job tractable. The mission vehicle becomes largely self-assembling, using its own rigid aerobrake as a work platform. The Space Station, having been used as a laboratory testbed and to house an assembly crew of four, is not dominated by the process. A feasible development schedule, if begun soon, could emplace orbital support technologies for exploration missions in time for a 2004 first <span class="hlt">interplanetary</span> launch.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015MsT..........2M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015MsT..........2M"><span>Statistical Study of <span class="hlt">Interplanetary</span> Coronal Mass Ejections with Strong <span class="hlt">Magnetic</span> Fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Murphy, Matthew E.</p> <p></p> <p>Coronal Mass Ejections (CMEs) with strong <span class="hlt">magnetic</span> fields (B ) are typically associated with significant Solar Energetic Particle (SEP) events, high solar wind speed and solar flare events. Successful prediction of the arrival time of a CME at Earth is required to maximize the time available for satellite, infrastructure, and space travel programs to take protective action against the coming flux of high-energy particles. It is known that the <span class="hlt">magnetic</span> field strength of a CME is linked to the strength of a geomagnetic storm on Earth. Unfortunately, the correlations between strong <span class="hlt">magnetic</span> field CMEs from the entire sun (especially from the far side or non-Earth facing side of the sun) to SEP and flare events, solar source regions and other relevant solar variables are not well known. New correlation studies using an artificial intelligence engine (Eureqa) were performed to study CME events with <span class="hlt">magnetic</span> field strength readings over 30 nanoteslas (nT) from January 2010 to October 17, 2014. This thesis presents the results of this study, validates Eureqa to obtain previously published results, and presents previously unknown functional relationships between solar source <span class="hlt">magnetic</span> field data, CME initial speed and the CME <span class="hlt">magnetic</span> field. These new results enable the development of more accurate CME <span class="hlt">magnetic</span> field predictions and should help scientists develop better forecasts thereby helping to prevent damage to humanity's space and Earth assets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880059402&hterms=quasi+particle&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dquasi%2Bparticle','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880059402&hterms=quasi+particle&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dquasi%2Bparticle"><span>Downstream energetic proton and alpha particles during quasi-parallel <span class="hlt">interplanetary</span> shock events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tan, L. C.; Mason, G. M.; Gloeckler, G.; Ipavich, F. M.</p> <p>1988-01-01</p> <p>This paper considers the energetic particle populations in the downstream region of three quasi-parallel <span class="hlt">interplanetary</span> shock events, which was explored using the ISEE 3 Ultra Low Energy Charge Analyzer sensor, which unambiguously identifies protons and alpha particles using the electrostatic deflection versus residual energy technique. The downstream particles were found to exhibit anisotropies due largely to convection in the solar wind. The spectral indices of the proton and the alpha-particle distribution functions were found to be remarkably constant during the downstream period, being generally insensitive to changes in particle flux levels, <span class="hlt">magnetic</span> field direction, and solar wind densities. In two of the three events, the proton and the alpha spectra were the same throughout the entire downstream period, supporting the prediction of diffusive shock acceleration theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...859L..29Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...859L..29Z"><span>Effects of Coronal <span class="hlt">Magnetic</span> Field Structures on the Transport of Solar Energetic Particles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhao, Lulu; Zhang, Ming</p> <p>2018-06-01</p> <p>This Letter presents a model calculation of solar energetic particle (SEP) transport to test the sensitivity of the distribution of escaped SEPs in <span class="hlt">interplanetary</span> space and dependence upon the details of the <span class="hlt">magnetic</span> field structure in the corona. It is applied to a circumsolar event on 2011 November 3, in which SEPs are observed promptly after the solar event eruption by three spacecraft (the twin Solar TErrestrial RElations Observatories (STEREO-A and STEREO-B) and ACE) separated by more than 100° in longitude from each other. The corona <span class="hlt">magnetic</span> field reconstructed from photosphseric field measurements using the PFSS method changes substantially before and after the solar eruption, especially around the active region. The locations of open field regions, separatrix surfaces including the heliospheric current sheet, and footpoints of <span class="hlt">magnetic</span> field lines connected to the spacecraft location have shifted substantially. We inject 100 keV energetic electrons on the open field lines at 1.5 R s within the size of observed coronal mass ejections (CMEs) and follow their propagation in the corona and the <span class="hlt">interplanetary</span> space. We find that with a perpendicular diffusion due to field line random walk equal to 10% of the supergranular diffusion rate, the overall distribution of escaped SEPs does not change much even though the region of open field lines from SEPs has changed. The result suggests that detailed small-scale coronal <span class="hlt">magnetic</span> field structures and the exact <span class="hlt">magnetic</span> field connection are not crucially important for observing SEPs in the <span class="hlt">interplanetary</span> space.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19860012006','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19860012006"><span>Study of Travelling <span class="hlt">Interplanetary</span> Phenomena (STIP) workshop travel</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, S. T.</p> <p>1986-01-01</p> <p>Thirty six abstracts are provided from the SCOSTEP/STIP Symposium on Retrospective Analyses and Future Coordinated Intervals held in Switzerland on June 10 to 12, 1985. Six American scientists participated in the symposium and their abstracts are also included. The titles of their papers are: (1) An analysis of near surface and coronal activity during STIP interval 12, by T. E. Gergely; (2) Helios images of STIP intervals 6, B. V. Jackson; (3) Results from the analysis of solar and <span class="hlt">interplanetary</span> observations during STIP interval 7, S. R. Kane; (4) STIP interval 19, E. Cliver; (5) Hydrodynamic buoyancy force in the solar atmosphere, T. Yeh; and (6) A combined MHD modes for the energy and momentum transport from solar surface to <span class="hlt">interplanetary</span> space, S. T. Wu.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840005054','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840005054"><span>Velocity profiles of <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cane, H. V.</p> <p>1983-01-01</p> <p>The type 2 radio burst was identified as a shock propagating through solar corona. Radio emission from shocks travelling through the <span class="hlt">interplanetary</span> (IP) medium was observed. Using the drift rates of IP type II bursts the velocity characteristics of eleven shocks were investigated. It is indicated that shocks in the IP medium undergo acceleration before decelerating and that the slower shocks take longer to attain their maximum velocity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1200613-bounce-mlt-averaged-diffusion-coefficients-physics-based-magnetic-field-geometry-obtained-from-ram-scb-march-storm','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1200613-bounce-mlt-averaged-diffusion-coefficients-physics-based-magnetic-field-geometry-obtained-from-ram-scb-march-storm"><span>Bounce- and MLT-<span class="hlt">averaged</span> diffusion coefficients in a physics-based <span class="hlt">magnetic</span> field geometry obtained from RAM-SCB for the March 17 2013 storm</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Zhao, Lei; Yu, Yiqun; Delzanno, Gian Luca; ...</p> <p>2015-04-01</p> <p>Local acceleration via whistler wave and particle interaction plays a significant role in particle dynamics in the radiation belt. In this work we explore gyro-resonant wave-particle interaction and quasi-linear diffusion in different <span class="hlt">magnetic</span> field configurations related to the March 17 2013 storm. We consider the Earth's <span class="hlt">magnetic</span> dipole field as a reference and compare the results against non-dipole field configurations corresponding to quiet and stormy conditions. The latter are obtained with the ring current-atmosphere interactions model with a self-consistent <span class="hlt">magnetic</span> field RAM-SCB, a code that models the Earth's ring current and provides a realistic modeling of the Earth's <span class="hlt">magnetic</span> field.more » By applying quasi-linear theory, the bounce- and MLT-<span class="hlt">averaged</span> electron pitch angle, mixed term, and energy diffusion coefficients are calculated for each <span class="hlt">magnetic</span> field configuration. For radiation belt (~1 MeV) and ring current (~100 keV) electrons, it is shown that at some MLTs the bounce-<span class="hlt">averaged</span> diffusion coefficients become rather insensitive to the details of the <span class="hlt">magnetic</span> field configuration, while at other MLTs storm conditions can expand the range of equatorial pitch angles where gyro-resonant diffusion occurs and significantly enhance the diffusion rates. When MLT <span class="hlt">average</span> is performed at drift shell L = 4.25 (a good approximation to drift <span class="hlt">average</span>), the diffusion coefficients become quite independent of the <span class="hlt">magnetic</span> field configuration for relativistic electrons, while the opposite is true for lower energy electrons. These results suggest that, at least for the March 17 2013 storm and for L ≲ 4.25, the commonly adopted dipole approximation of the Earth's <span class="hlt">magnetic</span> field can be safely used for radiation belt electrons, while a realistic modeling of the <span class="hlt">magnetic</span> field configuration is necessary to describe adequately the diffusion rates of ring current electrons.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/1200613','SCIGOV-STC'); return false;" href="https://www.osti.gov/servlets/purl/1200613"><span>Bounce- and MLT-<span class="hlt">averaged</span> diffusion coefficients in a physics-based <span class="hlt">magnetic</span> field geometry obtained from RAM-SCB for the March 17 2013 storm</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Zhao, Lei; Yu, Yiqun; Delzanno, Gian Luca</p> <p></p> <p>Local acceleration via whistler wave and particle interaction plays a significant role in particle dynamics in the radiation belt. In this work we explore gyro-resonant wave-particle interaction and quasi-linear diffusion in different <span class="hlt">magnetic</span> field configurations related to the March 17 2013 storm. We consider the Earth's <span class="hlt">magnetic</span> dipole field as a reference and compare the results against non-dipole field configurations corresponding to quiet and stormy conditions. The latter are obtained with the ring current-atmosphere interactions model with a self-consistent <span class="hlt">magnetic</span> field RAM-SCB, a code that models the Earth's ring current and provides a realistic modeling of the Earth's <span class="hlt">magnetic</span> field.more » By applying quasi-linear theory, the bounce- and MLT-<span class="hlt">averaged</span> electron pitch angle, mixed term, and energy diffusion coefficients are calculated for each <span class="hlt">magnetic</span> field configuration. For radiation belt (~1 MeV) and ring current (~100 keV) electrons, it is shown that at some MLTs the bounce-<span class="hlt">averaged</span> diffusion coefficients become rather insensitive to the details of the <span class="hlt">magnetic</span> field configuration, while at other MLTs storm conditions can expand the range of equatorial pitch angles where gyro-resonant diffusion occurs and significantly enhance the diffusion rates. When MLT <span class="hlt">average</span> is performed at drift shell L = 4.25 (a good approximation to drift <span class="hlt">average</span>), the diffusion coefficients become quite independent of the <span class="hlt">magnetic</span> field configuration for relativistic electrons, while the opposite is true for lower energy electrons. These results suggest that, at least for the March 17 2013 storm and for L ≲ 4.25, the commonly adopted dipole approximation of the Earth's <span class="hlt">magnetic</span> field can be safely used for radiation belt electrons, while a realistic modeling of the <span class="hlt">magnetic</span> field configuration is necessary to describe adequately the diffusion rates of ring current electrons.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160003519','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160003519"><span>Rapid Preliminary Design of <span class="hlt">Interplanetary</span> Trajectories Using the Evolutionary Mission Trajectory Generator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Englander, Jacob</p> <p>2016-01-01</p> <p>This set of tutorial slides is an introduction to the Evolutionary Mission Trajectory Generator (EMTG), NASA Goddard Space Flight Center's autonomous tool for preliminary design of <span class="hlt">interplanetary</span> missions. This slide set covers the basics of creating and post-processing simple <span class="hlt">interplanetary</span> missions in EMTG using both high-thrust chemical and low-thrust electric propulsion along with a variety of operational constraints.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AdSpR..60..153R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AdSpR..60..153R"><span>Probing interferometric parallax with <span class="hlt">interplanetary</span> spacecraft</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodeghiero, G.; Gini, F.; Marchili, N.; Jain, P.; Ralston, J. P.; Dallacasa, D.; Naletto, G.; Possenti, A.; Barbieri, C.; Franceschini, A.; Zampieri, L.</p> <p>2017-07-01</p> <p>We describe an experimental scenario for testing a novel method to measure distance and proper motion of astronomical sources. The method is based on multi-epoch observations of amplitude or intensity correlations between separate receiving systems. This technique is called Interferometric Parallax, and efficiently exploits phase information that has traditionally been overlooked. The test case we discuss combines amplitude correlations of signals from deep space <span class="hlt">interplanetary</span> spacecraft with those from distant galactic and extragalactic radio sources with the goal of estimating the <span class="hlt">interplanetary</span> spacecraft distance. Interferometric parallax relies on the detection of wavefront curvature effects in signals collected by pairs of separate receiving systems. The method shows promising potentialities over current techniques when the target is unresolved from the background reference sources. Developments in this field might lead to the construction of an independent, geometrical cosmic distance ladder using a dedicated project and future generation instruments. We present a conceptual overview supported by numerical estimates of its performances applied to a spacecraft orbiting the Solar System. Simulations support the feasibility of measurements with a simple and time-saving observational scheme using current facilities.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010128','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010128"><span>The Radiation, <span class="hlt">Interplanetary</span> Shocks, and Coronal Sources (RISCS) Toolset</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zank, G. P.; Spann, James F.</p> <p>2014-01-01</p> <p>The goal of this project is to serve the needs of space system designers and operators by developing an <span class="hlt">interplanetary</span> radiation environment model within 10 AU:Radiation, <span class="hlt">Interplanetary</span> Shocks, and Coronal Sources (RISCS) toolset: (1) The RISCS toolset will provide specific reference environments for space system designers and nowcasting and forecasting capabilities for space system operators; (2) We envision the RISCS toolset providing the spatial and temporal radiation environment external to the Earth's (and other planets') magnetosphere, as well as possessing the modularity to integrate separate applications (apps) that can map to specific magnetosphere locations and/or perform the subsequent radiation transport and dosimetry for a specific target.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...837L..17T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...837L..17T"><span>Sheath-accumulating Propagation of <span class="hlt">Interplanetary</span> Coronal Mass Ejection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Takahashi, Takuya; Shibata, Kazunari</p> <p>2017-03-01</p> <p>Fast <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) are the drivers of strong space weather storms such as solar energetic particle events and geomagnetic storms. The connection between the space-weather-impacting solar wind disturbances associated with fast ICMEs at Earth and the characteristics of causative energetic CMEs observed near the Sun is a key question in the study of space weather storms, as well as in the development of practical space weather prediction. Such shock-driving fast ICMEs usually expand at supersonic speeds during the propagation, resulting in the continuous accumulation of shocked sheath plasma ahead. In this paper, we propose a “sheath-accumulating propagation” (SAP) model that describes the coevolution of the <span class="hlt">interplanetary</span> sheath and decelerating ICME ejecta by taking into account the process of upstream solar wind plasma accumulation within the sheath region. Based on the SAP model, we discuss (1) ICME deceleration characteristics; (2) the fundamental condition for fast ICMEs at Earth; (3) the thickness of <span class="hlt">interplanetary</span> sheaths; (4) arrival time prediction; and (5) the super-intense geomagnetic storms associated with huge solar flares. We quantitatively show that not only the speed but also the mass of the CME are crucial for discussing the above five points. The similarities and differences between the SAP model, the drag-based model, and the“snow-plow” model proposed by Tappin are also discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22654525-sheath-accumulating-propagation-interplanetary-coronal-mass-ejection','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22654525-sheath-accumulating-propagation-interplanetary-coronal-mass-ejection"><span>Sheath-accumulating Propagation of <span class="hlt">Interplanetary</span> Coronal Mass Ejection</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Takahashi, Takuya; Shibata, Kazunari, E-mail: takahasi@kusastro.kyoto-u.ac.jp</p> <p></p> <p>Fast <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) are the drivers of strong space weather storms such as solar energetic particle events and geomagnetic storms. The connection between the space-weather-impacting solar wind disturbances associated with fast ICMEs at Earth and the characteristics of causative energetic CMEs observed near the Sun is a key question in the study of space weather storms, as well as in the development of practical space weather prediction. Such shock-driving fast ICMEs usually expand at supersonic speeds during the propagation, resulting in the continuous accumulation of shocked sheath plasma ahead. In this paper, we propose a “sheath-accumulating propagation”more » (SAP) model that describes the coevolution of the <span class="hlt">interplanetary</span> sheath and decelerating ICME ejecta by taking into account the process of upstream solar wind plasma accumulation within the sheath region. Based on the SAP model, we discuss (1) ICME deceleration characteristics; (2) the fundamental condition for fast ICMEs at Earth; (3) the thickness of <span class="hlt">interplanetary</span> sheaths; (4) arrival time prediction; and (5) the super-intense geomagnetic storms associated with huge solar flares. We quantitatively show that not only the speed but also the mass of the CME are crucial for discussing the above five points. The similarities and differences between the SAP model, the drag-based model, and the“snow-plow” model proposed by Tappin are also discussed.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AnGeo..32..157T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AnGeo..32..157T"><span>A model of the magnetosheath <span class="hlt">magnetic</span> field during <span class="hlt">magnetic</span> clouds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Turc, L.; Fontaine, D.; Savoini, P.; Kilpua, E. K. J.</p> <p>2014-02-01</p> <p><span class="hlt">Magnetic</span> clouds (MCs) are huge <span class="hlt">interplanetary</span> structures which originate from the Sun and have a paramount importance in driving magnetospheric storms. Before reaching the magnetosphere, MCs interact with the Earth's bow shock. This may alter their structure and therefore modify their expected geoeffectivity. We develop a simple 3-D model of the magnetosheath adapted to MCs conditions. This model is the first to describe the interaction of MCs with the bow shock and their propagation inside the magnetosheath. We find that when the MC encounters the Earth centrally and with its axis perpendicular to the Sun-Earth line, the MC's <span class="hlt">magnetic</span> structure remains mostly unchanged from the solar wind to the magnetosheath. In this case, the entire dayside magnetosheath is located downstream of a quasi-perpendicular bow shock. When the MC is encountered far from its centre, or when its axis has a large tilt towards the ecliptic plane, the MC's structure downstream of the bow shock differs significantly from that upstream. Moreover, the MC's structure also differs from one region of the magnetosheath to another and these differences vary with time and space as the MC passes by. In these cases, the bow shock configuration is mainly quasi-parallel. Strong <span class="hlt">magnetic</span> field asymmetries arise in the magnetosheath; the sign of the <span class="hlt">magnetic</span> field north-south component may change from the solar wind to some parts of the magnetosheath. We stress the importance of the Bx component. We estimate the regions where the magnetosheath and magnetospheric <span class="hlt">magnetic</span> fields are anti-parallel at the magnetopause (i.e. favourable to reconnection). We find that the location of anti-parallel fields varies with time as the MCs move past Earth's environment, and that they may be situated near the subsolar region even for an initially northward <span class="hlt">magnetic</span> field upstream of the bow shock. Our results point out the major role played by the bow shock configuration in modifying or keeping the structure of the MCs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730006137','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730006137"><span>The <span class="hlt">interplanetary</span> pioneers. Volume 1: Summary</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Corliss, W. R.</p> <p>1972-01-01</p> <p>The Pioneer Space Probe Project is explained to document the events which occurred during the project. The subjects discussed are: (1) origin and history of <span class="hlt">interplanetary</span> Pioneer program, (2) Pioneer system development and design, (3) Pioneer flight operations, and (4) Pioneer scientific results. Line drawings, circuit diagrams, illustrations, and photographs are included to augment the written material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940016180&hterms=1076&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3D%2526%25231076','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940016180&hterms=1076&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3D%2526%25231076"><span>Helium in <span class="hlt">interplanetary</span> dust particles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nier, A. O.; Schlutter, D. J.</p> <p>1993-01-01</p> <p>Helium and neon were extracted from fragments of individual stratosphere-collected <span class="hlt">interplanetary</span> dust particles (IDP's) by subjecting them to increasing temperature by applying short-duration pulses of power in increasing amounts to the ovens containing the fragments. The experiment was designed to see whether differences in release temperatures could be observed which might provide clues as to the asteroidal or cometary origin of the particles. Variations were observed which show promise for elucidating the problem.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120018044','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120018044"><span><span class="hlt">Interplanetary</span> Electric Propulsion Uranus Mission Trades Supporting the Decadal Survey</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dankanich, John W.; McAdams, James</p> <p>2011-01-01</p> <p>The Decadal Survey Committee was tasked to develop a comprehensive science and mission strategy for planetary science that updates and extends the National Academies Space Studies Board s current solar system exploration decadal survey. A Uranus orbiter mission has been evaluated as a part of this 2013-2022 Planetary Science Decadal Survey. A comprehensive Uranus orbiter mission design was completed, including a broad search of <span class="hlt">interplanetary</span> electric propulsion transfer options. The scope of <span class="hlt">interplanetary</span> trades was limited to electric propulsion concepts, both solar and radioisotope powered. Solar electric propulsion offers significant payloads to Uranus. Inserted mass into the initial science orbit due is highly sensitive to transfer time due to arrival velocities. The recommended baseline trajectory is a 13 year transfer with an Atlas 551, a 1+1 NEXT stage with 15 kW of power using an EEJU trajectory and a 1,000km EGA flyby altitude constraint. This baseline delivers over 2,000kg into the initial science orbit. <span class="hlt">Interplanetary</span> trajectory trades and sensitivity analyses are presented herein.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFMSH21A0513W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFMSH21A0513W"><span>Vector velocity profiles of the solar wind within expanding <span class="hlt">magnetic</span> clouds at 1 AU: Some surprises</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, C.; Lepping, R. P.; Berdichevsky, D.; Ferguson, T.; Lazarus, A. J.</p> <p>2002-12-01</p> <p>We investigated the <span class="hlt">average</span> vector velocity profile of 36 carefully chosen WIND <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds occurring over about a 7 year period since spacecraft launch, to see if a differential pattern of solar wind flow exists. Particular cases were chosen of clouds whose axes were generally within 45 degrees of the ecliptic plane and of relatively well determined characteristics obtained from cloud-parameter (cylindrically symmetric force free) fitting. This study was motivated by the desire to understand the manner in which <span class="hlt">magnetic</span> clouds expand, a well know phenomenon revealed by most cloud speed-profiles at 1 AU. One unexpected and major result was that, even though cloud expansion was confirmed, it was primarily along the Xgse axis; i.e., neither the Ygse or Zgse velocity components reveal any noteworthy pattern. After splitting the full set of clouds into a north-passing set (spacecraft passing above the cloud, where Nn = 21) and south-passing set (Ns = 15), to study the plasma expansion of the clouds with respect to the position of the observer, it was seen that the Xgse component of velocity differs for these two sets in a rather uniform and measurable way for most of the <span class="hlt">average</span> cloud's extent. This does not appear to be the case for the Ygse or Zgse velocity components where little measurable differences exists, and clearly no pattern, across the <span class="hlt">average</span> cloud between the north and south positions. It is not clear why such a remarkably non-axisymmetric plasma flow pattern within the "<span class="hlt">average</span> <span class="hlt">magnetic</span> cloud" at 1 AU should exist. The study continues from the perspective of <span class="hlt">magnetic</span> cloud coordinate representation. ~ ~ ~</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19940011836','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19940011836"><span>Carbon abundances, major element chemistry, and mineralogy of hydrated <span class="hlt">interplanetary</span> dust particles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Keller, L. P.; Thomas, K. L.; Mckay, D. S.</p> <p>1993-01-01</p> <p>Hydrated <span class="hlt">interplanetary</span> dust particles (IDP's) comprise a major fraction of the <span class="hlt">interplanetary</span> dust particles collected in the stratosphere. While much is known about the mineralogy and chemistry of hydrated IDP's, little is known about the C abundance in this class of IDP's, the nature of the C-bearing phases, and how the C abundance is related to other physical properties of hydrated IDP's. Bulk compositional data (including C and O) for 11 hydrated IDP's that were subsequently examined by the transition electron microscopy (TEM) to determine their mineralogy and mineral chemistry are reported. Our analysis indicates that these hydrated IDP's are strongly enriched in C relative to the most C-rich meteorites. The <span class="hlt">average</span> abundance of C in these hydrated IDP's is 4X CI chondrite values. The bulk compositions (including C and O) of 11 hydrated IDP's were determined by thin-window, energy-dispersive x ray (EDX) spectroscopy of the uncoated IDP's on Be substrates in the scanning electron microscopy (SEM). As a check on our C measurements, one of the IDP's (L2006H5) was embedded in glassy S, and microtome thin sections were prepared and placed onto Be substrates. Thin-film EDX analyses of multiple thin sections of L2006H5 show good agreement with the bulk value determined in the SEM. Following EDX analysis, the mineralogy and mineral chemistry of each IDP was determined by analyzing ultramicrotome thin sections in a TEM equipped with an EDX spectrometer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Ge%26Ae..57..512N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Ge%26Ae..57..512N"><span>Does <span class="hlt">magnetic</span> storm generation depend on the solar wind type?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nikolaeva, N. S.; Yermolaev, Yu. I.; Lodkina, I. G.; Yermolaev, M. Yu.</p> <p>2017-09-01</p> <p>The purpose of this work is to draw the reader's attention to the problem of possible differences in the generation of <span class="hlt">magnetic</span> storms by different large-scale solar wind types: corotating interaction regions (CIRs), Sheaths, and <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs), including <span class="hlt">magnetic</span> clouds (MCs) and Ejecta. We recently showed that the description of relationships between <span class="hlt">interplanetary</span> conditions and Dst and Dst* indices with the modified formula by Burton et al. gives an 50% higher efficiency of storm generation by Sheath and CIR than that by ICME. Many function couplings (FCs) between different <span class="hlt">interplanetary</span> parameters and the magnetosphere state have been suggested in the literature; however, they have not been analyzed for different solar wind types. In this work, we study the generation efficiency of the main phase of a storm by different solar wind streams with the use of 12 FCs on the basis of OMNI data for 1976-2000. The results show that the Sheath has the highest efficiency for most FCs, and MC is the least efficient, and this result corresponds to our previous results. The reliability of the results and possible causes of differences for different FCs and solar wind types are to be studied further.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770044460&hterms=1076&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3D%2526%25231076','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770044460&hterms=1076&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3D%2526%25231076"><span>Consequences of using nonlinear particle trajectories to compute spatial diffusion coefficients. [for cosmic ray propagation in interstellar and <span class="hlt">interplanetary</span> space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goldstein, M. L.</p> <p>1977-01-01</p> <p>In a study of cosmic ray propagation in interstellar and <span class="hlt">interplanetary</span> space, a perturbed orbit resonant scattering theory for pitch angle diffusion in a slab model of magnetostatic turbulence is slightly generalized and used to compute the diffusion coefficient for spatial propagation parallel to the mean <span class="hlt">magnetic</span> field. This diffusion coefficient has been useful for describing the solar modulation of the galactic cosmic rays, and for explaining the diffusive phase in solar flares in which the initial anisotropy of the particle distribution decays to isotropy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA092369','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA092369"><span>A Study of the Association of Pc 3, 4 Micropulsations with <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Orientation & Other Solar Wind Parameters.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1977-11-13</p> <p>Page 13 DEPENDENCE OF MEDIAN LOG POWER 1.0 ON SOLAR WIND VELOCITY Pc3 PULSATIONS June - September 1974 UCLA Fluxgate Magnetometer ATS - 6 0 Log P=-3.3...<span class="hlt">interplanetary</span> medium; Cosmic Elec., 1, 90-114, Space Sci. Rev., in press, 1978. 1970. Rusaell, C T., The ISEE I and 2 fluxgate magnetometers IEEE Fairfield. D...investigation is to attain the capacity to use micropulsation records acquired from surface magnetometers to infer certain key parameters of the solar wind</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790022947','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790022947"><span><span class="hlt">Interplanetary</span> particles and fields, November 22 - December 6, 1977: Helios, Voyager, and IMP observations between 0.6 AU and 1.6 AU</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burlaga, L. F.; Lepping, R. P.; Weber, R.; Armstrong, T.; Goodrich, C.; Sullivan, J.; Gurnett, D.; Kellogg, P.; Keppler, E.; Mariani, F.</p> <p>1979-01-01</p> <p>The principal <span class="hlt">interplanetary</span> events observed are described and analyzed. Three flow systems were observed: (1) a corotating stream and a stream interface associated with a coronal hole; (2) a shock wave and an energetic particle event associated with a 2-B flare; and (3) an isolated shock wave of uncertain origin. Data from 28 experiments and 6 spacecraft provide measurements of solar wind plasma, <span class="hlt">magnetic</span> fields, plasma waves, radio waves, energetic electrons, and low energy protons.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSM52A..07K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSM52A..07K"><span>Radiation Belt response to the July 2017 Coronal Mass Ejection and the <span class="hlt">Interplanetary</span> Shock</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kanekal, S. G.; Baker, D. N.; Jones, A. D.; Schiller, Q. A.; Sibeck, D. G.; Elkington, S. R.; Hoxie, V. C.; Jaynes, A. N.; Li, X.; Zhao, H.; Blake, J. B.; Claudepierre, S. G.; Fennell, J. F.; Turner, D. L.</p> <p>2017-12-01</p> <p>A coronal mass ejection that erupted on July 14, 2017 impacted the radiation belts on July 16, 2017 and resulted in a moderate geomagnetic storm. The immediate response of the energetic electrons to the <span class="hlt">interplanetary</span> shock ahead of the CME, showed hock-induced energization as well as drift echoes in the L range of 4 to 5 . Increased electron fluxes were seen to energies up to 5 MeV as observed by the Relativistic Electron and Proton Telescope and the <span class="hlt">Magnetic</span> Electron and Ion Sensors on board NASA's Van Allen Probes. We report on these observations, both immediately after the IP shock passage and the more gradual response to the CME. we discuss the observation in the context of electron dynamics in the terrestrial radiation belts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150007933','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150007933"><span>Comparisons of Characteristics of <span class="hlt">Magnetic</span> Clouds and Cloud-Like Structures During 1995-2012</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wu, Chin-Chun; Lepping, Ronald P.</p> <p>2015-01-01</p> <p>Using eighteen years (1995 - 2012) of solar wind plasma and <span class="hlt">magnetic</span> field data (observed by the Wind spacecraft), solar activity (e.g. sunspot number: SSN), and the geomagnetic activity index (Dst), we have identified 168 <span class="hlt">magnetic</span> clouds (MCs) and 197 <span class="hlt">magnetic</span> cloud - like structures (MCLs), and we have made relevant comparisons. The following features are found during seven different periods (TP: Total period during 1995 - 2012, P1 and P2: first and second half period during 1995 - 2003 and 2004 - 2012, Q1 and Q2: quiet periods during 1995 - 1997 and 2007 - 2009, A1 and A2: active periods during 1998 - 2006 and 2010 - 2012). (1) During the total period the yearly occurrence frequency is 9.3 for MCs and 10.9 for MCLs. (2) In the quiet periods <NMCs>Q1 > <NMCLs>Q1 and <NMCs>Q2 > <NMCLs>Q2, but in the active periods <NMCs>A1 < <NMCLs>A1 and <NMCs>A2 < <NMCLs>A2. (3) The minimum Bz (Bzmin) inside of a MC is well correlated with the intensity of geomagnetic activity, Dstmin (minimum Dst found within a storm event) for MCs (with a Pearson correlation coefficient, c.c. = 0.75, and the fitting function is Dstmin = 0.90+7.78Bzmin), but Bzmin for MCLs is not well correlated with the Dst index (c.c. = 0.56, and the fitting function is Dstmin = -9.40+ 4.58 Bzmin). (4) MCs play a major role in producing geomagnetic storms: the absolute value of the <span class="hlt">average</span> Dstmin (<Dstmin>MC = -70 nT) for MCs associated geomagnetic storms is two times stronger than that for MCLs (<Dstmin>MCL = -35 nT), due to the difference in the IMF (<span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field) strength. (5) The SSN is not correlated with MCs (<NMCs>TP, c.c. = 0.27), but is well associated with MCLs (<NMCLs>TP, c.c. = 0.85). Note that the c.c. for SSN vs. <NMCs>P2 is higher than that for SSN vs. <NMCLs>P2. (6) <span class="hlt">Averages</span> of IMF, solar wind speed, and density inside of the MCs are higher than those inside of the MCLs. (7) The <span class="hlt">average</span> of MC duration (approx. = 18.82 hours) is approx. = 20 % longer than the <span class="hlt">average</span> of MCL</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810043222&hterms=Harvard&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHarvard','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810043222&hterms=Harvard&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DHarvard"><span>Solar and <span class="hlt">interplanetary</span> dynamics; Proceedings of the Symposium, Harvard University, Cambridge, Mass., August 27-31, 1979</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dryer, M. (Editor); Tandberg-Hanssen, E.</p> <p>1980-01-01</p> <p>The symposium focuses on solar phenomena as the source of transient events propagating through the solar system, and theoretical and observational assessments of the dynamic processes involved in these events. The topics discussed include the life history of coronal structures and fields, coronal and <span class="hlt">interplanetary</span> responses to long time scale phenomena, solar transient phenomena affecting the corona and <span class="hlt">interplanetary</span> medium, coronal and <span class="hlt">interplanetary</span> responses to short time scale phenomena, and future directions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018P%26SS..156....7O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018P%26SS..156....7O"><span>Effects of <span class="hlt">interplanetary</span> coronal mass ejections on the transport of nano-dust generated in the inner solar system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>O'Brien, Leela; Juhász, Antal; Sternovsky, Zoltan; Horányi, Mihály</p> <p>2018-07-01</p> <p>This article reports on an investigation of the effect of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) on the transport and delivery of nano-dust to 1 AU. Charged nanometer-sized dust particles are expected to be generated close to the Sun and interact strongly with the solar wind as well as solar transient events. Nano-dust generated outside of ∼0.2 AU are picked up and transported away from the Sun due to the electromagnetic forces exerted by the solar wind. A numerical model has been developed to calculate the trajectories of nano-dust through their interaction with the solar wind and explore the potential for their detection near Earth's orbit (Juhasz and Horanyi, 2013). Here, we extend the model to include the interaction with <span class="hlt">interplanetary</span> coronal mass ejections. We report that ICMEs can greatly alter nano-dust trajectories, their transport to 1 AU, and their distribution near Earth's orbit. The smallest nano-dust (<10 nm) can be delivered to 1 AU in high concentration. Thus, the nature of the interaction between nano-dust and ICMEs could potentially be revealed by simultaneous measurements of nano-dust fluxes and solar wind particles/<span class="hlt">magnetic</span> fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cosp...40E1802L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cosp...40E1802L"><span>Link between <span class="hlt">interplanetary</span> & cometary dust: Polarimetric observations and space studies with Rosetta & Eye-Sat</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Levasseur-Regourd, Anny-Chantal; Gaboriaud, Alain; Buil, Christian; Ressouche, Antoine; Lasue, J.; Palun, Adrien; Apper, Fabien; Elmaleh, Marc</p> <p></p> <p>Intensity and linear polarization observations of the solar light scattered by <span class="hlt">interplanetary</span> dust, the so-called zodiacal light, provide information on properties of the dust particles, such as their spatial density, local changes, morphology and albedo. Earth-based polarimetric observations, with a resolution of 5° or more, have been used to derive the polarization phase curve of <span class="hlt">interplanetary</span> dust particles and to establish that the polarization at 90° phase angle increases with increasing solar distance, at least up to 1.5 au in the ecliptic, while the albedo decreases [1, 2]. Analysis of such studies will be revisited. Numerical simulations of the polarimetric behavior of <span class="hlt">interplanetary</span> dust particles strongly suggest that, in the inner solar system, <span class="hlt">interplanetary</span> dust particles consist of absorbing (e.g., organic compounds) and less absorbing (e.g., silicates) materials, that radial changes originate in a decrease of organics with decreasing solar distance (probably due to alteration processes), and that a significant fraction of the <span class="hlt">interplanetary</span> dust is of cometary origin, in agreement with dynamical studies [3, 4]. The polarimetric behaviors of <span class="hlt">interplanetary</span> dust and cometary dust particles seem to present striking similarities. The properties of cometary dust particles, as derived from remote polarimetric observations of comets including 67P/Churyumov-Gerasimenko, the target of the Rosetta rendezvous mission, at various wavelengths, will be summarized [5, 6]. The ground truth expected from Rosetta dust experiments, i.e., MIDAS, COSIMA, GIADA, about dust particles’ morphology, composition, and evolution (with distance to the nucleus before Philae release and with distance to the Sun before and after perihelion passage) over the year and a half of nominal mission, will be discussed. Finally, the Eye-Sat nanosatellite will be presented. This triple cubesat, developed by students from engineering schools working as interns at CNES, is to be launched</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AdSpR..61..749Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AdSpR..61..749Y"><span>Science objectives of the <span class="hlt">magnetic</span> field experiment onboard Aditya-L1 spacecraft</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yadav, Vipin K.; Srivastava, Nandita; Ghosh, S. S.; Srikar, P. T.; Subhalakshmi, Krishnamoorthy</p> <p>2018-01-01</p> <p>The Aditya-L1 is first Indian solar mission scheduled to be placed in a halo orbit around the first Lagrangian point (L1) of Sun-Earth system in the year 2018-19. The approved scientific payloads onboard Aditya-L1 spacecraft includes a Fluxgate Digital Magnetometer (FGM) to measure the local <span class="hlt">magnetic</span> field which is necessary to supplement the outcome of other scientific experiments onboard. The in-situ vector <span class="hlt">magnetic</span> field data at L1 is essential for better understanding of the data provided by the particle and plasma analysis experiments, onboard Aditya-L1 mission. Also, the dynamics of Coronal Mass Ejections (CMEs) can be better understood with the help of in-situ <span class="hlt">magnetic</span> field data at the L1 point region. This data will also serve as crucial input for the short lead-time space weather forecasting models. The proposed FGM is a dual range <span class="hlt">magnetic</span> sensor on a 6 m long boom mounted on the Sun viewing panel deck and configured to deploy along the negative roll direction of the spacecraft. Two sets of sensors (tri-axial each) are proposed to be mounted, one at the tip of boom (6 m from the spacecraft) and other, midway (3 m from the spacecraft). The main science objective of this experiment is to measure the magnitude and nature of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) locally and to study the disturbed <span class="hlt">magnetic</span> conditions and extreme solar events by detecting the CME from Sun as a transient event. The proposed secondary science objectives are to study the impact of <span class="hlt">interplanetary</span> structures and shock solar wind interaction on geo-space environment and to detect low frequency plasma waves emanating from the solar corona at L1 point. This will provide a better understanding on how the Sun affects <span class="hlt">interplanetary</span> space. In this paper, we shall give the main scientific objectives of the <span class="hlt">magnetic</span> field experiment and brief technical details of the FGM onboard Aditya-1 spacecraft.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016LSSR....8....1G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016LSSR....8....1G"><span>Effect of zero <span class="hlt">magnetic</span> field on cardiovascular system and microcirculation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gurfinkel, Yu. I.; At'kov, O. Yu.; Vasin, A. L.; Breus, T. K.; Sasonko, M. L.; Pishchalnikov, R. Yu.</p> <p>2016-02-01</p> <p>The effects of zero <span class="hlt">magnetic</span> field conditions on cardiovascular system of healthy adults have been studied. In order to generate zero <span class="hlt">magnetic</span> field, the facility for <span class="hlt">magnetic</span> fields modeling ;ARFA; has been used. Parameters of the capillary blood flow, blood pressure, and the electrocardiogram (ECG) monitoring were measured during the study. All subjects were tested twice: in zero <span class="hlt">magnetic</span> field and, for comparison, in sham condition. The obtained results during 60 minutes of zero <span class="hlt">magnetic</span> field exposure demonstrate a clear effect on cardiovascular system and microcirculation. The results of our experiments can be used in studies of long-term stay in hypo-<span class="hlt">magnetic</span> conditions during <span class="hlt">interplanetary</span> missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920059359&hterms=dropout&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddropout','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920059359&hterms=dropout&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddropout"><span><span class="hlt">Interplanetary</span> <span class="hlt">magnetic</span> field connection to the sun during electron heat flux dropouts in the solar wind</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lin, R. P.; Kahler, S. W.</p> <p>1992-01-01</p> <p>The paper discusses observations of 2- to 8.5-keV electrons, made by measurements aboard the ISEE 3 spacecraft during the periods of heat flux decreases (HFDs) reported by McComas et al. (1989). In at least eight of the total of 25 HFDs observed, strong streaming of electrons that were equal to or greater than 2 keV outward from the sun was recorded. In one HFD, an impulsive solar electron event was observed with an associated type III radio burst, which could be tracked from the sun to about 1 AU. It is concluded that, in many HFDs, the <span class="hlt">interplanetary</span> field is still connected to the sun and that some energy-dependent process may produce HFDs without significantly perturbing electrons of higher energies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5376862-study-relationship-between-interplanetary-parameters-large-displacements-nightside-polar-cap-boundary','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5376862-study-relationship-between-interplanetary-parameters-large-displacements-nightside-polar-cap-boundary"><span>A study of the relationship between <span class="hlt">interplanetary</span> parameters and large displacements of the nightside polar cap boundary</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Lester, M.; Freeman, M.P.; Southwood, D.J.</p> <p></p> <p>On July 14, 1982 the Sweden and Britain Radar-Aurora Experiment (SABRE) observed the ionospheric flow reversal boundary at {approximately} 0400 MLT to move equatorward across the radar field of view and then later to return poleward. The polar cap appeared to be considerably inflated at this time. Concurrent observations by ISEE-3 at the L1 libration point of the solar wind speed and density, and of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) indicated that the solar wind conditions were unusual throughout the interval under consideration. A mapping of the solar wind parameters from the L1 point to the subsolar magnetopause and thencemore » to the SABRE local time sector indicates that the equatorward motion of the polar cap boundary was controlled by a southward turning of the IMF. The inference of a concomitant increase in open <span class="hlt">magnetic</span> flux is supported by a comparison of the magnetopause location observed by ISEE-1 on an inbound pass in the 2,100 MLT sector with a magnetopause model based upon the solar wind measurements made by ISEE-3. Some 20 minutes after the expansion of the polar cap boundary was first seen by SABRE, there was a rapid contraction of the boundary, the casue of which was independent of the INF and solar wind parameters, and which had a poleward velocity component in excess of 1,900 m s{sup {minus}1}. the boundary as it moved across the radar field of view was highly structured and oriented at a large angle to the ionospheric footprints of the <span class="hlt">magnetic</span> L shells. Observations in the premidnight sector by the Air Force Geophysics Laboratory (AFGL) magnetometer array indicate that the polar cap contraction is caused by substorm draining of the polar cap flux and occurs without a clearly associated trigger in the <span class="hlt">interplanetary</span> medium. The response time in the early morning local time sector to the substorm onset switch is approximately 20 minutes, equivalent to an ionospheric azimuthal phase velocity of some 5 km s{sup {minus}1}.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19960021340&hterms=solar+two&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Btwo','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19960021340&hterms=solar+two&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dsolar%2Btwo"><span>The solar origins of two high-latitude <span class="hlt">interplanetary</span> disturbances</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hudson, H. S.; Acton, L. W.; Alexander, D.; Harvey, K. L.; Kurokawa, H.; Kahler, S.; Lemen, J. R.</p> <p>1995-01-01</p> <p>Two extremely similar <span class="hlt">interplanetary</span> forward/reverse shock events, with bidirectional electron streaming were detected by Ulysses in 1994. Ground-based and Yohkoh/SXT observations show two strikingly different solar events that could be associated with them: an LDE flare on 20 Feb. 1994, and a extremely large-scale eruptive event on 14 April 1994. Both events resulted in geomagnetic storms and presumably were associated with coronal mass ejections. The sharply contrasting nature of these solar events argues against an energetic causal relationship between them and the bidirectional streaming events observed by Ulysses during its S polar passage. We suggest instead that for each pair of events. a common solar trigger may have caused independent instabilities leading to the solar and <span class="hlt">interplanetary</span> phenomena.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRA..123.1191B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRA..123.1191B"><span>Variations of the Electron Fluxes in the Terrestrial Radiation Belts Due To the Impact of Corotating Interaction Regions and <span class="hlt">Interplanetary</span> Coronal Mass Ejections</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Benacquista, R.; Boscher, D.; Rochel, S.; Maget, V.</p> <p>2018-02-01</p> <p>In this paper, we study the variations of the radiation belts electron fluxes induced by the interaction of two types of solar wind structures with the Earth magnetosphere: the corotating interaction regions and the <span class="hlt">interplanetary</span> coronal mass ejections. We use a statistical method based on the comparison of the preevent and postevent fluxes. Applied to the National Oceanic and Atmospheric Administration-Polar Operational Environmental Satellites data, this gives us the opportunity to extend previous studies focused on relativistic electrons at geosynchronous orbit. We enlighten how corotating interaction regions and <span class="hlt">Interplanetary</span> Coronal Mass Ejections can impact differently the electron belts depending on the energy and the L shell. In addition, we provide a new insight concerning these variations by considering their amplitude. Finally, we show strong relations between the intensity of the <span class="hlt">magnetic</span> storms related to the events and the variation of the flux. These relations concern both the capacity of the events to increase the flux and the deepness of these increases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800018764','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800018764"><span>Hourly <span class="hlt">average</span> values of solar wing parameters (flow rate and ion temperatures) according to data of measurements of the Venera-9 and Venera-10 automatic <span class="hlt">interplanetary</span> stations on an Earth-Venus during the period June 1975 - April 1976</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vaysberg, O. L.; Dyachkov, A. V.; Smirnov, V. N.; Tsyrkin, K. B.; Isaeva, R. A.</p> <p>1980-01-01</p> <p>Four electrostatic analyzers with channel electron multipliers as detectors were used to measure solar wind ionic flow. The axes of the fields of vision of two of these analyzers were directed along the axis of the automatic <span class="hlt">interplanetary</span> station, oriented towards the Sun, while the other two were turned in one plane at angles of +15 deg and -15 deg. The full hemisphere of the angular diagram of each analyzer was approximately 5 deg. The energetic resolution was approximately 6%, and the geometric energy was 0.002 sq cm ave. keV. Each analyzer covered an energetic range of approximately 10 in eight energetic intervals. Spectral distributions were processed in order to obtain the velocity and temperature of the protons. Tabular data show the hour interval (universal time) and the <span class="hlt">average</span> solar wind velocity in kilometers per second.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800063628&hterms=monsanto&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmonsanto','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800063628&hterms=monsanto&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dmonsanto"><span>Optical spectroscopy of <span class="hlt">interplanetary</span> dust collected in the earth's stratosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fraundorf, P.; Patel, R. I.; Shirck, J.; Walker, R. M.; Freeman, J. J.</p> <p>1980-01-01</p> <p>Optical absorption spectra of <span class="hlt">interplanetary</span> dust particles 2-30 microns in size collected in the atmosphere at an altitude of 20 km by inertial impactors mounted on NASA U-2 aircraft are reported. Fourier transform absorption spectroscopy of crushed samples of the particles reveals a broad feature in the region 1300-800 kaysers which has also been found in meteorite and cometary dust spectra, and a weak iron crystal field absorption band at approximately 9800 kaysers, as is observed in meteorites. Work is currently in progress to separate the various components of the <span class="hlt">interplanetary</span> dust particles in order to evaluate separately their contributions to the absorption.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002560&hterms=electrons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Delectrons','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002560&hterms=electrons&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Delectrons"><span>Electron-Scale Measurements of <span class="hlt">Magnetic</span> Reconnection in Space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burch, J. L.; Torbert, R. B.; Phan, T. D.; Chen, L.-J.; Moore, T. E.; Ergun, R. E.; Eastwood, J. P.; Gershman, D. J.; Cassak, P. A.; Argall, M. R.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20170002560'); toggleEditAbsImage('author_20170002560_show'); toggleEditAbsImage('author_20170002560_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20170002560_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20170002560_hide"></p> <p>2016-01-01</p> <p><span class="hlt">Magnetic</span> reconnection is a fundamental physical process in plasmas whereby stored <span class="hlt">magnetic</span> energy is converted into heat and kinetic energy of charged particles. Reconnection occurs in many astrophysical plasma environments and in laboratory plasmas. Using measurements with very high time resolution, NASA's Magnetospheric Multiscale (MMS) mission has found direct evidence for electron demagnetization and acceleration at sites along the sunward boundary of Earth's magnetosphere where the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field reconnects with the terrestrial <span class="hlt">magnetic</span> field. We have (i) observed the conversion of <span class="hlt">magnetic</span> energy to particle energy; (ii) measured the electric field and current, which together cause the dissipation of <span class="hlt">magnetic</span> energy; and (iii) identified the electron population that carries the current as a result of demagnetization and acceleration within the reconnection diffusion/dissipation region.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950029575&hterms=dependency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Ddependency','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950029575&hterms=dependency&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Ddependency"><span><span class="hlt">Interplanetary</span> <span class="hlt">magnetic</span> field dependency of stable Sun-aligned polar cap arcs</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Valladares, C. E.; Carlson, H. C., Jr.; Fukui, K.</p> <p>1994-01-01</p> <p>This is the first analysis, using a statistically significant data set, of the morphological dependence of the presence, orientation, and motion of stable sun-aligned polar cap arcs upon the vector <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF). For the one winter season analyzed we had 1392 all-sky 630.0-nm images of 2-min resolution containing a total of 150 polar cap arcs, all with corresponding values of the IMF as measured by International Monitoring Platform (IMP) 8 or International Sun Earth Explorer (ISEE) 2. After demonstrating an unbiased data set with smooth normal distributions of events versus the dimensions of time, space, and IMF component, we examine IMF dependencies of the properties of the optical arcs. A well-defined dependence for B(sub z) is found for the presence/absence of stable Sun-aligned polar cap arcs. Consistent with previous statistical studies, the probability of observing polar cap aurora steadily increases for larger positive values of B(sub z), and linearly decreases when B(sub z) becomes more negative. The probability of observing Sun-aligned arcs within the polar cap is determined to vary sharply as a function of the arc location; arcs were observed 40% of the time on the dawnside and only 10% on the duskside. This implies an overall probability of at least 40% for the whole polar cap. 20% of the arcs were observed during 'southward IMF conditions,' but in fact under closer inspection were found to have been formed under northward IMF conditions; these 'residual' positive B(sub z) arcs ha d a delayed residence time in the polar cap of about what would be expected after a north to south transition of B(sub z). A firm dependence on B(sub y) is also found for both the orientation and the dawn-dusk direction of motion of the arcs. All the arcs are Sun-aligned to a first approximation, but present deviations from this orientation, depending primarily upon the location of the arc in corrected geomagnetic (CG) coordinates. The arcs populating the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AAS...21010901Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AAS...21010901Q"><span>Amid the Tempest: An Observational View of <span class="hlt">Magnetic</span> Reconnection in Explosions on the Sun</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Qiu, Jiong</p> <p>2007-05-01</p> <p>Viewed through telescopes, the Sun is a restless star. Frequently, impulsive brightenings in the Sun's atmosphere, known as solar flares, are observed across a broad range of the electromagnetic spectrum. It is considered that solar flares are driven by <span class="hlt">magnetic</span> reconnection, when anti-parallel <span class="hlt">magnetic</span> field lines collide and reconnect with each other, efficiently converting free <span class="hlt">magnetic</span> energy into heating plasmas and accelerating charged particles. Over the past decades, solar physicists have discovered observational signatures as indirect evidence for <span class="hlt">magnetic</span> reconnection. Careful analyses of these observations lead to evaluation of key physical parameters of <span class="hlt">magnetic</span> reconnection. Growing efforts have been extended to understand the process of <span class="hlt">magnetic</span> reconnection in some of the most spectacular explosions on the Sun in the form of coronal mass ejections (CMEs). Often accompanied by flares, nearly once a day, a large bundle of plasma wrapped in <span class="hlt">magnetic</span> field lines is violently hurled out of the Sun into <span class="hlt">interplanetary</span> space. This is a CME. CMEs are driven <span class="hlt">magnetically</span>, although the exact mechanisms remain in heated debate. Among many mysteries of CMEs, a fundamental question has been the origin of the specific <span class="hlt">magnetic</span> structure of CMEs, some reaching the earth and being observed in-situ as a nested set of helical field lines, or a <span class="hlt">magnetic</span> flux rope. Analyses of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> flux ropes and their solar progenitors, including flares and CMEs, provide an observational insight into the role of <span class="hlt">magnetic</span> reconnection at the early stage of flux rope eruption.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008JASS...25...33J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008JASS...25...33J"><span>TEC Variations Over Korean Peninsula During <span class="hlt">Magnetic</span> Storm</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ji, E.-Y.; Choi, B.-K.; Kim, K.-H.; Lee, D.-H.; Cho, J.-H.; Chung, J.-K.; Park, J.-U.</p> <p>2008-03-01</p> <p>By analyzing the observations from a number of ground- and space-based instruments, including ionosonde, magnetometers, and ACE <span class="hlt">interplanetary</span> data, we examine the response of the ionospheric TEC over Korea during 2003 <span class="hlt">magnetic</span> storms. We found that the variation of vertical TEC is correlated with the southward turning of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field B_z. It is suggested that the electric fields produced by the dynamo process in the high-latitude region and the prompt penetration in the low-latitude region are responsible for TEC increases. During the June 16 event, dayside TEC values increase more than 15%. And the ionospheric F2-layer peak height (hmF2) was ˜300km higher and the vertical E×B drift (estimated from ground-based magnetometer equatorial electrojet delta H) showed downward drift, which may be due to the ionospheric disturbance dynamo electric field produced by the large amount of energy dissipation into high-latitude regions. In contr! ast, during November 20 event, the nightside TEC increases may be due to the prompt penetration westward electric field. The ionospheric F2-layer peak height was below 200km and the vertical E×B drift showed downward drift. Also, a strong correlation is observed between enhanced vertical TEC and enhanced <span class="hlt">interplanetary</span> electric field. It is shown that, even though TEC increases are caused by the different processes, the electric field disturbances in the ionosphere play an important role in the variation of TEC over Korea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005DPS....37.1702G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005DPS....37.1702G"><span>GEO Debris and <span class="hlt">Interplanetary</span> Dust: Fluxes and Charging Behavior</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Graps, A. L.; Green, S. F.; McBride, N. M.; McDonnell, J. A. M.; Drolshagen, G.; Svedhem, H.; Bunte, K. D.</p> <p>2005-08-01</p> <p>A population of cosmic dust mixed with a population of man-made debris exists within the Earth's magnetosphere. Measurements of these provide the data samples for studies of the <span class="hlt">interplanetary</span> dust particles that travel through our magnetosphere from the outside and for studies of the local byproducts of our space endeavours. Even though instruments to detect natural meteoroids and space debris particles have been flown in Low Earth Orbits (LEO) and on <span class="hlt">interplanetary</span> missions, very little information on the particle environment for Earth orbits above about 600 km altitude have been available. In particular, knowledge about particles smaller than 1 m in the geostationary (GEO) region was largely unknown before GORID. In September 1996, a dust/debris detector: GORID was launched into GEO as a piggyback instrument on the Russian Express-2 telecommunications spacecraft. The instrument began its normal operation in April 1997 and ended its mission in July 2002. The goal of this work was to use GORID's particle data to identify and separate the space debris from the <span class="hlt">interplanetary</span> dust particles (IDPs) in GEO, to more finely determine the instrument's measurement characteristics and to derive impact fluxes. Here we present some results of that study. We give GORID flux distributions for debris and IDPs and then present intriguing debris clustering features that might be the result of electrostatic fragmentation of the rocket slag particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18218892','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18218892"><span>Comparison of comet 81P/Wild 2 dust with <span class="hlt">interplanetary</span> dust from comets.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ishii, Hope A; Bradley, John P; Dai, Zu Rong; Chi, Miaofang; Kearsley, Anton T; Burchell, Mark J; Browning, Nigel D; Molster, Frank</p> <p>2008-01-25</p> <p>The Stardust mission returned the first sample of a known outer solar system body, comet 81P/Wild 2, to Earth. The sample was expected to resemble chondritic porous <span class="hlt">interplanetary</span> dust particles because many, and possibly all, such particles are derived from comets. Here, we report that the most abundant and most recognizable silicate materials in chondritic porous <span class="hlt">interplanetary</span> dust particles appear to be absent from the returned sample, indicating that indigenous outer nebula material is probably rare in 81P/Wild 2. Instead, the sample resembles chondritic meteorites from the asteroid belt, composed mostly of inner solar nebula materials. This surprising finding emphasizes the petrogenetic continuum between comets and asteroids and elevates the astrophysical importance of stratospheric chondritic porous <span class="hlt">interplanetary</span> dust particles as a precious source of the most cosmically primitive astromaterials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSA43B2363D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSA43B2363D"><span>Time-dependent radiation dose estimations during <span class="hlt">interplanetary</span> space flights</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dobynde, M. I.; Shprits, Y.; Drozdov, A.</p> <p>2015-12-01</p> <p>Time-dependent radiation dose estimations during <span class="hlt">interplanetary</span> space flights 1,2Dobynde M.I., 2,3Drozdov A.Y., 2,4Shprits Y.Y.1Skolkovo institute of science and technology, Moscow, Russia 2University of California Los Angeles, Los Angeles, USA 3Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, Moscow, Russia4Massachusetts Institute of Technology, Cambridge, USASpace radiation is the main restriction for long-term <span class="hlt">interplanetary</span> space missions. It induces degradation of external components and propagates inside providing damage to internal environment. Space radiation particles and induced secondary particle showers can lead to variety of damage to astronauts in short- and long- term perspective. Contribution of two main sources of space radiation- Sun and out-of-heliosphere space varies in time in opposite phase due to the solar activity state. Currently the only habituated mission is the international <span class="hlt">interplanetary</span> station that flights on the low Earth orbit. Besides station shell astronauts are protected with the Earth magnetosphere- a natural shield that prevents significant damage for all humanity. Current progress in space exploration tends to lead humanity out of magnetosphere bounds. With the current study we make estimations of spacecraft parameters and astronauts damage for long-term <span class="hlt">interplanetary</span> flights. Applying time dependent model of GCR spectra and data on SEP spectra we show the time dependence of the radiation in a human phantom inside the shielding capsule. We pay attention to the shielding capsule design, looking for an optimal geometry parameters and materials. Different types of particles affect differently on the human providing more or less harm to the tissues. Incident particles provide a large amount of secondary particles while propagating through the shielding capsule. We make an attempt to find an optimal combination of shielding capsule parameters, namely material and thickness, that will effectively decrease</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22667509-small-scale-magnetic-islands-solar-wind-role-particle-acceleration-ii-particle-energization-inside-magnetically-confined-cavities','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22667509-small-scale-magnetic-islands-solar-wind-role-particle-acceleration-ii-particle-energization-inside-magnetically-confined-cavities"><span>SMALL-SCALE <span class="hlt">MAGNETIC</span> ISLANDS IN THE SOLAR WIND AND THEIR ROLE IN PARTICLE ACCELERATION. II. PARTICLE ENERGIZATION INSIDE <span class="hlt">MAGNETICALLY</span> CONFINED CAVITIES</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Khabarova, Olga V.; Zank, Gary P.; Li, Gang</p> <p>2016-08-20</p> <p>We explore the role of heliospheric <span class="hlt">magnetic</span> field configurations and conditions that favor the generation and confinement of small-scale <span class="hlt">magnetic</span> islands associated with atypical energetic particle events (AEPEs) in the solar wind. Some AEPEs do not align with standard particle acceleration mechanisms, such as flare-related or simple diffusive shock acceleration processes related to <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) and corotating interaction regions (CIRs). As we have shown recently, energetic particle flux enhancements may well originate locally and can be explained by particle acceleration in regions filled with small-scale <span class="hlt">magnetic</span> islands with a typical width of ∼0.01 au or less, whichmore » is often observed near the heliospheric current sheet (HCS). The particle energization is a consequence of <span class="hlt">magnetic</span> reconnection-related processes in islands experiencing either merging or contraction, observed, for example, in HCS ripples. Here we provide more observations that support the idea and the theory of particle energization produced by small-scale-flux-rope dynamics (Zank et al. and Le Roux et al.). If the particles are pre-accelerated to keV energies via classical mechanisms, they may be additionally accelerated up to 1–1.5 MeV inside <span class="hlt">magnetically</span> confined cavities of various origins. The <span class="hlt">magnetic</span> cavities, formed by current sheets, may occur at the interface of different streams such as CIRs and ICMEs or ICMEs and coronal hole flows. They may also form during the HCS interaction with <span class="hlt">interplanetary</span> shocks (ISs) or CIRs/ICMEs. Particle acceleration inside <span class="hlt">magnetic</span> cavities may explain puzzling AEPEs occurring far beyond ISs, within ICMEs, before approaching CIRs as well as between CIRs.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005BAAA...48...93N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005BAAA...48...93N"><span>Study of an expanding <span class="hlt">magnetic</span> cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakwacki, M. S.; Dasso, S.; Mandrini, C. H.; Démoulin, P.</p> <p></p> <p><span class="hlt">Magnetic</span> Clouds (MCs) transport into the <span class="hlt">interplanetary</span> medium the <span class="hlt">magnetic</span> flux and helicity released in coronal mass ejections by the Sun. At 1 AU from the Sun, MCs are generally modelled as static flux ropes. However, the velocity profile of some MCs presents signatures of expansion. We analise here the <span class="hlt">magnetic</span> structure of an expanding <span class="hlt">magnetic</span> cloud observed by Wind spacecraft. We consider a dynamical model, based on a self-similar behaviour for the cloud radial velocity. We assume a free expansion for the cloud, and a cylindrical linear force free field (i.e., the Lundquist's field) as the initial condition for its <span class="hlt">magnetic</span> configuration. We derive theoretical expressions for the <span class="hlt">magnetic</span> flux across a surface perpendicular to the cloud axis, for the <span class="hlt">magnetic</span> helicity and <span class="hlt">magnetic</span> energy per unit length along the tube using the self-similar model. Finally, we compute these magntitudes with the fitted parameters. FULL TEXT IN SPANISH</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800012928','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800012928"><span><span class="hlt">Interplanetary</span> monitoring platform engineering history and achievements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Butler, P. M.</p> <p>1980-01-01</p> <p>In the fall of 1979, last of ten <span class="hlt">Interplanetary</span> Monitoring Platform Satellite (IMP) missions ended a ten year series of flights dedicated to obtaining new knowledge of the radiation effects in outer space and of solar phenomena during a period of maximum solar flare activity. The technological achievements and scientific accomplishments from the IMP program are described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060036834&hterms=WIND+STORMS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWIND%2BSTORMS','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060036834&hterms=WIND+STORMS&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DWIND%2BSTORMS"><span>The Distant Tail Behavior During High Speed Solar Wind Streams and <span class="hlt">Magnetic</span> Storms</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ho, C. M.; Tsurutani, B. T.</p> <p>1996-01-01</p> <p>We have examined the ISEE-3 distant tail data during three intense (Dst< -100(sub n)T) <span class="hlt">magnetic</span> storms and have identified the tail response to high speed solar wind streams, <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> clouds, and near-Earth storms. The three storms have a peak Dst ranging from -150 to -220 nT, and occur on Jan. 9, Feb. 4, and Aug. 8, 1993.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20010026435','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20010026435"><span>Asynchronous Laser Transponders for Precise <span class="hlt">Interplanetary</span> Ranging and Time Transfer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Degnan, John J.; Smith, David E. (Technical Monitor)</p> <p>2001-01-01</p> <p>The feasibility of a two-way asynchronous (i.e. independently firing) <span class="hlt">interplanetary</span> laser transponder pair, capable of decimeter ranging and subnanosecond time transfer from Earth to a spacecraft anywhere within the inner Solar System, is discussed. In the Introduction, we briefly discuss the current state-of-the-art in Satellite Laser Ranging (SLR) and Lunar Laser Ranging (LLR) which use single-ended range measurements to a passive optical reflector, and the limitations of this approach in ranging beyond the Moon to the planets. In Section 2 of this paper, we describe two types of transponders (echo and asynchronous), introduce the transponder link equation and the concept of "balanced" transponders, describe how range and time can be transferred between terminals, and preview the potential advantages of photon counting asynchronous transponders for <span class="hlt">interplanetary</span> applications. In Section 3, we discuss and provide mathematical models for the various sources of noise in an <span class="hlt">interplanetary</span> transponder link including planetary albedo, solar or lunar illumination of the local atmosphere, and laser backscatter off the local atmosphere. In Section 4, we introduce the key engineering elements of an <span class="hlt">interplanetary</span> laser transponder and develop an operational scenario for the acquisition and tracking of the opposite terminal. In Section 5, we use the theoretical models of th previous sections to perform an Earth-Mars link analysis over a full synodic period of 780 days under the simplifying assumption of coaxial, coplanar, circular orbits. We demonstrate that, using slightly modified versions of existing space and ground based laser systems, an Earth-Mars transponder link is not only feasible but quite robust. We also demonstrate through analysis the advantages and feasibility of compact, low output power (<300 mW photon-counting transponders using NASA's developmental SLR2000 satellite laser ranging system as the Earth terminal. Section 6 provides a summary of the results</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38..712H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38..712H"><span>Physical properties of <span class="hlt">interplanetary</span> dust: laboratory and numerical simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hadamcik, Edith; Lasue, Jeremie; Levasseur-Regourd, Anny-Chantal; Renard, Jean-Baptiste; Buch, Arnaud; Carrasco, Nathalie; Cottin, Hervé; Fray, Nicolas; Guan, Yuan Yong; Szopa, Cyril</p> <p></p> <p>Laboratory light scattering measurements with the PROGRA2 experiment, in A300-CNES and ESA dedicated microgravity flights or in ground based configurations, offer an alternative to models for exploring the scattering properties of particles with structures too complex to be easily handled by computer simulations [1,2]. The technique allows the use of large size distributions (nanometers to hundreds of micrometers) and a large variety of materials, similar to those suspected to compose the <span class="hlt">interplanetary</span> particles [3]. Asteroids are probably the source of compact particles, while comets have been shown to eject compact and fluffy materials [4]. Moreover giant planets provide further a small number of <span class="hlt">interplanetary</span> particles. Some interstellar particles are also present. To choose the best samples and size distributions, we consider previous numerical models for the <span class="hlt">interplanetary</span> particles and their evolution with solar distance. In this model, fluffy particles are simulated by fractal aggregates and compact particles by ellipsoids. The materials considered are silicates and carbonaceous compound. The silicate grains can be coated by the organics. Observations are fitted with two parameters: the size distribution of the particles and the ratio of silicates over carbonaceous compounds. From the light scattering properties of the particles, their equilibrium temperature can be calculated for different structures and composition. The variation of their optical properties and temperatures are studied with the heliocentric distance [5,6]. Results on analogs of cometary particles [7] and powdered meteorites as asteroidal particles will be presented and compared to numerical simulations as well as observations. Organics on cometary grains can constitute distributed sources if degraded by solar UV and heat [8, 9]. The optical properties of CxHyNz compounds are studied after thermal evolution [10]. As a first approach, they are used to simulate the evolution of cometary or</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19890023530&hterms=Singled&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSingled','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19890023530&hterms=Singled&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DSingled"><span>The search for refractory <span class="hlt">interplanetary</span> dust particles from preindustrial aged Antarctic ice</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zolensky, Michael E.; Webb, Susan J.; Thomas, Kathie</p> <p>1988-01-01</p> <p>In a study of refractory <span class="hlt">interplanetary</span> dust particles, preindustrial-aged Antarctic ice samples have been collected, melted, and filtered to separate the particle load. Particles containing a significant amount of aluminum, titanium, and/or calcium were singled out for detailed SEM and STEM characterization. The majority of these particles are shown to be volcanic tephra from nearby volcanic centers. Six spherical aggregates were encountered that consist of submicron-sized grains of rutile within polycrystalline cristobalite. These particles are probably of terrestrial volcanic origin, but have not been previously reported from any environment. One aggregate particle containing fassaite and hibonite is described as a probable <span class="hlt">interplanetary</span> dust particle. The constituent grain sizes of this particle vary from 0.1 to 0.3 microns, making it significantly more fine-grained than meteoritic calcium-aluminum-rich inclusions. This particle is mineralogically and morphologically similar to recently reported refractory <span class="hlt">interplanetary</span> dust particles collected from the stratosphere, and dissimilar to the products of modern spacecraft debris.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH11B2388N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH11B2388N"><span>Modeling <span class="hlt">Magnetic</span> Flux-Ropes Structures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nieves-Chinchilla, T.; Linton, M.; Hidalgo, M. A. U.; Vourlidas, A.; Savani, N.; Szabo, A.; Farrugia, C. J.; Yu, W.</p> <p>2015-12-01</p> <p>Flux-ropes are usually associated with <span class="hlt">magnetic</span> structures embedded in the <span class="hlt">interplanetary</span> Coronal Mass Ejections (ICMEs) with a depressed proton temperature (called <span class="hlt">Magnetic</span> Clouds, MCs). However, small-scale flux-ropes in the solar wind are also identified with different formation, evolution, and dynamic involved. We present an analytical model to describe <span class="hlt">magnetic</span> flux-rope topologies. The model is generalized to different grades of complexity. It extends the circular-cylindrical concept of Hidalgo et al. (2002) by introducing a general form for the radial dependence of the current density. This generalization provides information on the force distribution inside the flux rope in addition to the usual parameters of flux-rope geometrical information and orientation. The generalized model provides flexibility for implementation in 3-D MHD simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19850002589','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19850002589"><span>Structure and evolution of the large scale solar and heliospheric <span class="hlt">magnetic</span> fields. Ph.D. Thesis</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hoeksema, J. T.</p> <p>1984-01-01</p> <p>Structure and evolution of large scale photospheric and coronal <span class="hlt">magnetic</span> fields in the interval 1976-1983 were studied using observations from the Stanford Solar Observatory and a potential field model. The solar wind in the heliosphere is organized into large regions in which the <span class="hlt">magnetic</span> field has a componenet either toward or away from the sun. The model predicts the location of the current sheet separating these regions. Near solar minimum, in 1976, the current sheet lay within a few degrees of the solar equator having two extensions north and south of the equator. Soon after minimum the latitudinal extent began to increase. The sheet reached to at least 50 deg from 1978 through 1983. The complex structure near maximum occasionally included multiple current sheets. Large scale structures persist for up to two years during the entire interval. To minimize errors in determining the structure of the heliospheric field particular attention was paid to decreasing the distorting effects of rapid field evolution, finding the optimum source surface radius, determining the correction to the sun's polar field, and handling missing data. The predicted structure agrees with direct <span class="hlt">interplanetary</span> field measurements taken near the ecliptic and with coronameter and <span class="hlt">interplanetary</span> scintillation measurements which infer the three dimensional <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> structure. During most of the solar cycle the heliospheric field cannot be adequately described as a dipole.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20080048006','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20080048006"><span>The <span class="hlt">Interplanetary</span> Overlay Networking Protocol Accelerator</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pang, Jackson; Torgerson, Jordan L.; Clare, Loren P.</p> <p>2008-01-01</p> <p>A document describes the <span class="hlt">Interplanetary</span> Overlay Networking Protocol Accelerator (IONAC) an electronic apparatus, now under development, for relaying data at high rates in spacecraft and <span class="hlt">interplanetary</span> radio-communication systems utilizing a delay-tolerant networking protocol. The protocol includes provisions for transmission and reception of data in bundles (essentially, messages), transfer of custody of a bundle to a recipient relay station at each step of a relay, and return receipts. Because of limitations on energy resources available for such relays, data rates attainable in a conventional software implementation of the protocol are lower than those needed, at any given reasonable energy-consumption rate. Therefore, a main goal in developing the IONAC is to reduce the energy consumption by an order of magnitude and the data-throughput capability by two orders of magnitude. The IONAC prototype is a field-programmable gate array that serves as a reconfigurable hybrid (hardware/ firmware) system for implementation of the protocol. The prototype can decode 108,000 bundles per second and encode 100,000 bundles per second. It includes a bundle-cache static randomaccess memory that enables maintenance of a throughput of 2.7Gb/s, and an Ethernet convergence layer that supports a duplex throughput of 1Gb/s.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19407194','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19407194"><span>MESSENGER observations of <span class="hlt">magnetic</span> reconnection in Mercury's magnetosphere.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Slavin, James A; Acuña, Mario H; Anderson, Brian J; Baker, Daniel N; Benna, Mehdi; Boardsen, Scott A; Gloeckler, George; Gold, Robert E; Ho, George C; Korth, Haje; Krimigis, Stamatios M; McNutt, Ralph L; Raines, Jim M; Sarantos, Menelaos; Schriver, David; Solomon, Sean C; Trávnícek, Pavel; Zurbuchen, Thomas H</p> <p>2009-05-01</p> <p>Solar wind energy transfer to planetary magnetospheres and ionospheres is controlled by <span class="hlt">magnetic</span> reconnection, a process that determines the degree of connectivity between the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) and a planet's <span class="hlt">magnetic</span> field. During MESSENGER's second flyby of Mercury, a steady southward IMF was observed and the magnetopause was threaded by a strong <span class="hlt">magnetic</span> field, indicating a reconnection rate ~10 times that typical at Earth. Moreover, a large flux transfer event was observed in the magnetosheath, and a plasmoid and multiple traveling compression regions were observed in Mercury's magnetotail, all products of reconnection. These observations indicate that Mercury's magnetosphere is much more responsive to IMF direction and dominated by the effects of reconnection than that of Earth or the other <span class="hlt">magnetized</span> planets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016IAUTA..29..365J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016IAUTA..29..365J"><span>Division F Commission 22: Meteors, Meteorites, and <span class="hlt">Interplanetary</span> Dust</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jenniskens, Peter; Borovička, Jiří; Watanabe, Jun-Ichi; Jopek, Tadeusz; Abe, Shinsuke; Consolmagno, Guy J.; Ishiguro, Masateru; Janches, Diego; Ryabova, Galina O.; Vaubaillon, Jérémie; Zhu, Jin</p> <p>2016-04-01</p> <p>Commission 22 (Meteors, Meteorites and <span class="hlt">Interplanetary</span> Dust) was established at the first IAU General Assembly held in Rome in 1922, with William Frederick Denning as its first President. Denning was an accountant by profession, but as an amateur astronomer he contributed extensively to meteor science. Commission 22 thus established a pattern that has continued to this day that non-professional astronomers were welcomed and valued and could play a significant role in its affairs. The field of meteors, meteorites and <span class="hlt">interplanetary</span> dust has played a disproportional role in the astronomical perception of the general public through the majestic displays of our annual meteor showers. Those in the field deployed many techniques uncommon in other fields of astronomy, studying the ``vermin of space'', the small solid bodies that pervade <span class="hlt">interplanetary</span> space and impact Earth's atmosphere, the surface of the Moon, and that of our satellites in orbit. Over time, the field has tackled a wide array of problems, from predicting the encounter with meteoroid streams, to the origin of our meteorites and the nature of the zodiacal cloud. Commission 22 has played an important role in organizing the field through dedicated meetings, a data centre, and working groups that developed professional-amateur relationships and that organized the nomenclature of meteor showers. The contribution of Commission 22 to the field is perhaps most readily seen in the work of the presidents that followed in the footsteps of Denning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900023755&hterms=seeds&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dseeds','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900023755&hterms=seeds&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dseeds"><span>Seed population for about 1 MeV per nucleon heavy ions accelerated by <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tan, L. C.; Mason, G. M.; Klecker, B.; Hovestadt, D.</p> <p>1989-01-01</p> <p>Data obtained between 1977 and 1982 by the ISEE 1 and ISEE 3 satellites on the composition of heavy ions of about 1 MeV per nucleon, accelerated in <span class="hlt">interplanetary</span> shock events which followed solar flare events, are examined. It was found that the <span class="hlt">average</span> relative abundances for C, O, and Fe in the shock events were very close to those found for energetic ions in the solar flares, suggesting that, at these energies, the shock accelerated particles have the solar energetic particles as their seed population. This hypothesis is supported by the fact that the Fe/O ratio in the solar particle events is very strongly correlated with the Fe/O ratio in associated diffusive shock events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17833558','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17833558"><span>The <span class="hlt">magnetic</span> field of saturn: pioneer 11 observations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Acuña, M H; Ness, N F</p> <p>1980-01-25</p> <p>The intrinsic <span class="hlt">magnetic</span> field of Saturn measured by the high-field fluxgate magnetometer is much weaker than expected. An analysis of preliminary data combined with the preliminary trajectory yield a model for the main planetary field which is a simple centered dipole of moment 0.20 +/- 0.01 gauss-Rs(3) = 4.3 +/- 0.2 x 10(28) gauss-cm(3) (1 Rs = 1 Saturn radius = 60,000 km). The polarity is opposite that of Earth, and, surprisingly, the tilt is small, within 2 degrees +/- 1 degrees of the rotation axis. The equatorial field intensity at the cloud tops is 0.2 gauss, and the polar intensity is 0.56 gauss. The unique moon Titan is expected to be located within the magnetosheath of Saturn or the <span class="hlt">interplanetary</span> medium about 50 percent of the time because the <span class="hlt">average</span> subsolar point distance to the magnetosphere is estimated to be 20 Rs, the orbital distance to Titan.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1113L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1113L"><span>Radio Emmision during the interaction of two <span class="hlt">Interplanetary</span> Coronal Mass Ejections</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lara, Alejandro; Niembro, Tatiana; González, Ricardo</p> <p>2016-07-01</p> <p>We show that some sporadic radio emission observed by the WIND/WAVES experiment in the decametric/kilometric bands are due to the interaction of two <span class="hlt">interplanetary</span> Coronal Mass Ejections. We have performed hydrodynamic simulations of the evolution of two consecutive Coronal Mass ejections in the <span class="hlt">interplanetary</span> medium. With these simulations it is possible to follow the density evolution of the merged structure, and therefore, compute the frequency limits of the possible plasma emission. We study four well documented ICME interaction events, and found radio emission at the time and frequencies predicted by the simulations. This emission may help to anticipate the complexity of the merged region before it reaches one AU.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AdSpR..59.1425S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AdSpR..59.1425S"><span>The role of <span class="hlt">interplanetary</span> shock orientation on SC/SI rise time and geoeffectiveness</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Selvakumaran, R.; Veenadhari, B.; Ebihara, Y.; Kumar, Sandeep; Prasad, D. S. V. V. D.</p> <p>2017-03-01</p> <p><span class="hlt">Interplanetary</span> (IP) shocks interact with the Earth's magnetosphere, resulting in compression of the magnetosphere which in turn increases the Earth's <span class="hlt">magnetic</span> field termed as Sudden commencement/Sudden impulse (SC/SI). Apart from IP shock speed and solar wind dynamic pressure, IP shock orientation angle also plays a major role in deciding the SC rise time. In the present study, the IP shock orientation angle and SC/SI rise time for 179 IP shocks are estimated which occurred during solar cycle 23. More than 50% of the Shock orientations are in the range of 140°-160°. The SC/SI rise time decreases with the increase in the orientation angle and IP shock speed. In this work, the type of IP shocks i.e., Radio loud (RL) and Radio quiet (RQ) are examined in connection with SC/SI rise time. The RL associated IP shock speeds show a better correlation than RQ shocks with SC/SI rise time irrespective of the orientation angle. <span class="hlt">Magnetic</span> Cloud (MC) associated shocks dominate in producing less rise time when compared to Ejecta (EJ) shocks. Magneto hydrodynamic (MHD) simulations are used for three different IP shock orientation categories to see the importance of orientation angle in determining the geoeffectiveness. Simulations results reveal that shocks hitting parallel to the magnetosphere are more geoeffective as compared to oblique shocks by means of change in <span class="hlt">magnetic</span> field, pressure and Field Aligned Current (FAC).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1326029-time-dependent-mhd-simulations-solar-wind-outflow-using-interplanetary-scintillation-observations','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1326029-time-dependent-mhd-simulations-solar-wind-outflow-using-interplanetary-scintillation-observations"><span>Time-dependent MHD simulations of the solar wind outflow using <span class="hlt">interplanetary</span> scintillation observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Kim, Tae K.; Pogorelov, Nikolai V.; Borovikov, Sergey N.; ...</p> <p>2012-11-20</p> <p>Numerical modeling of the heliosphere is a critical component of space weather forecasting. The accuracy of heliospheric models can be improved by using realistic boundary conditions and confirming the results with in situ spacecraft measurements. To accurately reproduce the solar wind (SW) plasma flow near Earth, we need realistic, time-dependent boundary conditions at a fixed distance from the Sun. We may prepare such boundary conditions using SW speed and density determined from <span class="hlt">interplanetary</span> scintillation (IPS) observations, <span class="hlt">magnetic</span> field derived from photospheric magnetograms, and temperature estimated from its correlation with SW speed. In conclusion, we present here the time-dependent MHD simulationmore » results obtained by using the 2011 IPS data from the Solar-Terrestrial Environment Laboratory as time-varying inner boundary conditions and compare the simulated data at Earth with OMNI data (spacecraft-interspersed, near-Earth solar wind data).« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110011249','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110011249"><span><span class="hlt">Interplanetary</span> Propagation of Coronal Mass Ejections</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, Nat</p> <p>2011-01-01</p> <p>Although more than ten thousand coronal mass ejections (CMEs) are produced during each solar cycle at the Sun, only a small fraction hits the Earth. Only a small fraction of the Earth-directed CMEs ultimately arrive at Earth depending on their interaction with the solar wind and other large-scale structures such as coronal holes and CMEs. The <span class="hlt">interplanetary</span> propagation is essentially controlled by the drag force because the propelling force and the solar gravity are significant only near the Sun. Combined remote-sensing and in situ observations have helped us estimate the influence of the solar wind on the propagation of CMEs. However, these measurements have severe limitations because the remote-sensed and in-situ observations correspond to different portions of the CME. Attempts to overcome this problem are made in two ways: the first is to model the CME and get the space speed of the CME, which can be compared with the in situ speed. The second method is to use stereoscopic observation so that the remote-sensed and in-situ observations make measurements on the Earth-arriving part of CMEs. The Solar Terrestrial Relations Observatory (STEREO) mission observed several such CMEs, which helped understand the <span class="hlt">interplanetary</span> evolution of these CMEs and to test earlier model results. This paper discusses some of these issues and updates the CME/shock travel time estimates for a number of CMEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950017408','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950017408"><span>LDEF <span class="hlt">Interplanetary</span> Dust Experiment (IDE) results</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Oliver, John P.; Singer, S. F.; Weinberg, J. L.; Simon, C. G.; Cooke, W. J.; Kassel, P. C.; Kinard, W. H.; Mulholland, J. D.; Wortman, J. J.</p> <p>1995-01-01</p> <p>The <span class="hlt">Interplanetary</span> Dust Experiment (IDE) provided high time resolution detection of microparticle impacts on the Long Duration Exposure Facility satellite. Particles, in the diameter range from 0.2 microns to several hundred microns, were detected impacting on six orthogonal surfaces of the gravity-gradient stabilized LDEF spacecraft. The total sensitive surface area was about one square meter, distributed between LDEF rows 3 (Wake or West), 6 (South), 9 (Ram or East), 12 (North), as well as the Space and Earth ends of LDEF. The time of each impact is known to an accuracy that corresponds to better than one degree in orbital longitude. Because LDEF was gravity-gradient stabilized and <span class="hlt">magnetically</span> damped, the direction of the normal to each detector panel is precisely known for each impact. The 11 1/2 month tape-recorded data set represents the most extensive record gathered of the number, orbital location, and incidence direction for microparticle impacts in low Earth orbit. Perhaps the most striking result from IDE was the discovery that microparticle impacts, especially on the Ram, South, and North surfaces, were highly episodic. Most such impacts occurred in localized regions of the orbit for dozens or even hundreds of orbits in what we have termed Multiple Orbit Event Sequences (MOES). In addition, more than a dozen intense and short-lived 'spikes' were seen in which impact fluxes exceeded the background by several orders of magnitude. These events were distributed in a highly non-uniform fashion in time and terrestrial longitude and latitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150020817','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150020817"><span>Global Optimization of <span class="hlt">Interplanetary</span> Trajectories in the Presence of Realistic Mission Contraints</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hinckley, David, Jr.; Englander, Jacob; Hitt, Darren</p> <p>2015-01-01</p> <p><span class="hlt">Interplanetary</span> missions are often subject to difficult constraints, like solar phase angle upon arrival at the destination, velocity at arrival, and altitudes for flybys. Preliminary design of such missions is often conducted by solving the unconstrained problem and then filtering away solutions which do not naturally satisfy the constraints. However this can bias the search into non-advantageous regions of the solution space, so it can be better to conduct preliminary design with the full set of constraints imposed. In this work two stochastic global search methods are developed which are well suited to the constrained global <span class="hlt">interplanetary</span> trajectory optimization problem.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012cosp...39.1998T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012cosp...39.1998T"><span>Shielding Structures for <span class="hlt">Interplanetary</span> Human Mission</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tracino, Emanuele; Lobascio, Cesare</p> <p>2012-07-01</p> <p>Since the end of Apollo missions, human spaceflight has been limited to the Low Earth Orbit (LEO), inside the protective <span class="hlt">magnetic</span> field of the Earth, because astronauts are, to the largest degree, protected from the harsh radiation environment of the <span class="hlt">interplanetary</span> space. However, this situation will change when space exploration missions beyond LEO will become the real challenge of the human exploration program. The feasibility of these missions in the solar system is thus strongly connected to the capability to mitigate the radiation-induced biological effects on the crew during the journey and the permanence on the intended planet surface. Inside the International Space Station (ISS), the volumes in which the crew spends most of the time, namely the crew quarters are the only parts that implement dedicated additional radiation shielding made of polyethylene tiles designed for mitigating SPE effects. Furthermore, specific radiation shielding materials are often added to the described configuration to shield crew quarters or the entire habitat example of these materials are polyethylene, liquid hydrogen, etc. but, increasing the size of the exploration vehicles to bring humans beyond LEO, and without the magnetosphere protection, such approach is unsustainable because the mass involved is a huge limiting factor with the actual launcher engine technology. Moreover, shielding against GCR with materials that have a low probability of nuclear interactions and in parallel a high ionizing energy loss is not always the best solution. In particular there is the risk to increase the LET of ions arriving at the spacecraft shell, increasing their Radio-Biological Effectiveness. Besides, the production of secondary nuclei by projectile and target fragmentation is an important issue when performing an engineering assessment of materials to be used for radiation shielding. The goal of this work is to analyze different shielding solutions to increase as much as possible the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19910038864&hterms=quasi+particle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dquasi%2Bparticle','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19910038864&hterms=quasi+particle&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dquasi%2Bparticle"><span><span class="hlt">Interplanetary</span> particle beams</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dulk, G. A.</p> <p>1990-01-01</p> <p>This paper reviews observations of <span class="hlt">interplanetary</span> particle beams of the kind that frequently accompany a solar flare. It is shown that the most frequently observed beams are beams of electrons which are associated with radio bursts of type III, but occasionally with flares and X-ray bursts. Although the main features of these beams and their associated plasma waves and radio bursts are known, uncertainties remain in terms of the correlation between electron beams and filamentary structures, the relative importance of the quasi-linear and the nonlinear wave emissions as the dominant process, and the mechanism of conversion of some of the Langmuir wave energy into radio emissions. Other particle beams discussed are those composed of protons, neutrons, He ions, or heavy ions. While most of these beams originate from sun flares, the source of some of particle beams may be the earth, Jupiter, or other planets as well as comets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110007248','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110007248"><span>CME Interaction with Coronal Holes and Their <span class="hlt">Interplanetary</span> Consequences</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, N.; Makela, P.; Xie, H.; Akiyama, S.; Yashiro, S.</p> <p>2008-01-01</p> <p>A significant number of <span class="hlt">interplanetary</span> (IP) shocks (-17%) during cycle 23 were not followed by drivers. The number of such "driverless" shocks steadily increased with the solar cycle with 15%, 33%, and 52% occurring in the rise, maximum, and declining phase of the solar cycle. The solar sources of 15% of the driverless shocks were very close the central meridian of the Sun (within approx.15deg), which is quite unexpected. More interestingly, all the driverless shocks with their solar sources near the solar disk center occurred during the declining phase of solar cycle 23. When we investigated the coronal environment of the source regions of driverless shocks, we found that in each case there was at least one coronal hole nearby suggesting that the coronal holes might have deflected the associated coronal mass ejections (CMEs) away from the Sun-Earth line. The presence of abundant low-latitude coronal holes during the declining phase further explains why CMEs originating close to the disk center mimic the limb CMEs, which normally lead to driverless shocks due to purely geometrical reasons. We also examined the solar source regions of shocks with drivers. For these, the coronal holes were located such that they either had no influence on the CME trajectories. or they deflected the CMEs towards the Sun-Earth line. We also obtained the open <span class="hlt">magnetic</span> field distribution on the Sun by performing a potential field source surface extrapolation to the corona. It was found that the CMEs generally move away from the open <span class="hlt">magnetic</span> field regions. The CME-coronal hole interaction must be widespread in the declining phase, and may have a significant impact on the geoeffectiveness of CMEs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19990100646','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19990100646"><span><span class="hlt">Interplanetary</span> Fast Shocks and Associated Drivers Observed through the Twenty-Third Solar Minimum by WIND Over its First 2.5 Years</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mariani, F.; Berdichevsky, D.; Szabo, A.; Lepping, R. P.; Vinas, A. F.</p> <p>1999-01-01</p> <p>A list of the <span class="hlt">interplanetary</span> (IP) shocks observed by WIND from its launch (in November 1994) to May 1997 is presented. Forty two shocks were identified. The magnetohydrodynamic nature of the shocks is investigated, and the associated shock parameters and their uncertainties are accurately computed using a practical scheme which combines two techniques. These techniques are a combination of the "pre-<span class="hlt">averaged</span>" <span class="hlt">magnetic</span>-coplanarity, velocity-coplanarity, and the Abraham-Schrauner-mixed methods, on the one hand, and the Vinas and Scudder [1986] technique for solving the non-linear least-squares Rankine-Hugoniot shock equations, on the other. Within acceptable limits these two techniques generally gave the same results, with some exceptions. The reasons for the exceptions are discussed. It is found that the mean strength and rate of occurrence of the shocks appears to correlated with the solar cycle. Both showed a decrease in 1996 coincident with the time of the lowest ultraviolet solar radiance, indicative of solar minimum and start of solar cycle 23, which began around June 1996. Eighteen shocks appeared to be associated with corotating interaction regions (CIRs). The distribution of their shock normals showed a mean direction peaking in the ecliptic plane and with a longitude (phi(sub n)) in that plane between perpendicular to the Parker spiral and radial from the Sun. When grouped according to the sense of the direction of propagation of the shocks the mean azimuthal (longitude) angle in GSE coordinates was approximately 194 deg for the fast-forward and approximately 20 deg for the fast-reverse shocks. Another 16 shocks were determined to be driven by solar transients, including <span class="hlt">magnetic</span> clouds. These shocks had a broader distribution of normal directions than those of the CIR cases with a mean direction close to the Sun-Earth line. Eight shocks of unknown origin had normal orientation well off the ecliptic plane. No shock propagated with longitude phi(sub n) >= 220</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19730060305&hterms=method+magnetic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmethod%2Bmagnetic','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19730060305&hterms=method+magnetic&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmethod%2Bmagnetic"><span>A variation of the Davis-Smith method for in-flight determination of spacecraft <span class="hlt">magnetic</span> fields.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Belcher, J. W.</p> <p>1973-01-01</p> <p>A variation of a procedure developed by Davis and Smith (1968) is presented for the in-flight determination of spacecraft <span class="hlt">magnetic</span> fields. Both methods take statistical advantage of the observation that fluctuations in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field over short periods of time are primarily changes in direction rather than in magnitude. During typical solar wind conditions between 0.8 and 1.0 AU, a statistical analysis of 2-3 days of continuous <span class="hlt">interplanetary</span> field measurements yields an estimate of a constant spacecraft field with an uncertainty of plus or minus 0.25 gamma in the direction radial to the sun and plus or minus 15 gammas in the directions transverse to the radial. The method is also of use in estimating variable spacecraft fields with gradients of the order of 0.1 gamma/day and less and in other special circumstances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22521503-do-legs-magnetic-clouds-contain-twisted-flux-rope-magnetic-fields','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22521503-do-legs-magnetic-clouds-contain-twisted-flux-rope-magnetic-fields"><span>DO THE LEGS OF <span class="hlt">MAGNETIC</span> CLOUDS CONTAIN TWISTED FLUX-ROPE <span class="hlt">MAGNETIC</span> FIELDS?</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Owens, M. J.</p> <p>2016-02-20</p> <p><span class="hlt">Magnetic</span> clouds (MCs) are a subset of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs) characterized primarily by a smooth rotation in the <span class="hlt">magnetic</span> field direction indicative of the presence of a <span class="hlt">magnetic</span> flux rope. Energetic particle signatures suggest MC flux ropes remain <span class="hlt">magnetically</span> connected to the Sun at both ends, leading to widely used model of global MC structure as an extended flux rope, with a loop-like axis stretching out from the Sun into the heliosphere and back to the Sun. The time of flight of energetic particles, however, suggests shorter <span class="hlt">magnetic</span> field line lengths than such a continuous twisted flux ropemore » would produce. In this study, two simple models are compared with observed flux rope axis orientations of 196 MCs to show that the flux rope structure is confined to the MC leading edge. The MC “legs,” which <span class="hlt">magnetically</span> connect the flux rope to the Sun, are not recognizable as MCs and thus are unlikely to contain twisted flux rope fields. Spacecraft encounters with these non-flux rope legs may provide an explanation for the frequent observation of non-MC ICMEs.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPSC...10..744G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPSC...10..744G"><span>CLIpSAT for <span class="hlt">Interplanetary</span> Missions: Common Low-cost <span class="hlt">Interplanetary</span> Spacecraft with Autonomy Technologies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grasso, C.</p> <p>2015-10-01</p> <p>Blue Sun Enterprises, Inc. is creating a common deep space bus capable of a wide variety of Mars, asteroid, and comet science missions, observational missions in and near GEO, and <span class="hlt">interplanetary</span> delivery missions. The spacecraft are modular and highly autonomous, featuring a common core and optional expansion for variable-sized science or commercial payloads. Initial spacecraft designs are targeted for Mars atmospheric science, a Phobos sample return mission, geosynchronous reconnaissance, and en-masse delivery of payloads using packetized propulsion modules. By combining design, build, and operations processes for these missions, the cost and effort for creating the bus is shared across a variety of initial missions, reducing overall costs. A CLIpSAT can be delivered to different orbits and still be able to reach <span class="hlt">interplanetary</span> targets like Mars due to up to 14.5 km/sec of delta-V provided by its high-ISP Xenon ion thruster(s). A 6U version of the spacecraft form fits PPOD-standard deployment systems, with up to 9 km/s of delta-V. A larger 12-U (with the addition of an expansion module) enables higher overall delta-V, and has the ability to jettison the expansion module and return to the Earth-Moon system from Mars orbit with the main spacecraft. CLIpSAT utilizes radiation-hardened electronics and RF equipment, 140+ We of power at earth (60 We at Mars), a compact navigation camera that doubles as a science imager, and communications of 2000 bps from Mars to the DSN via X-band. This bus could form the cornerstone of a large number asteroid survey projects, comet intercept missions, and planetary observation missions. The TugBot architecture uses groups of CLIpSATs attached to payloads lacking innate high-delta-V propulsion. The TugBots use coordinated trajectory following by each individual spacecraft to move the payload to the desired orbit - for example, a defense asset might be moved from GEO to lunar transfer orbit in order to protect and hide it, then returned</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840005034','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840005034"><span><span class="hlt">Interplanetary</span> scintillation observations of the solar wind close to the Sun and out of the ecliptic</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sime, D. G.</p> <p>1983-01-01</p> <p>A brief review is given of recent developments in the observation of the solar wind by the method of <span class="hlt">interplanetary</span> scintillation. The emphasis is on observations of the velocity structure, the electron density and the effect of propagating disturbances in the <span class="hlt">interplanetary</span> medium as detected principally by intensity and phase scintillation and by spectral broadening.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910973D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910973D"><span>MAVEN observations of complex <span class="hlt">magnetic</span> field topology in the Martian magnetotail</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DiBraccio, Gina A.; Espley, Jared R.; Luhmann, Janet G.; Curry, Shannon M.; Gruesbeck, Jacob R.; Connerney, John E. P.; Soobiah, Yasir; Xu, Shaosui; Mitchell, David M.; Harada, Yuki; Halekas, Jasper S.; Brain, David A.; Dong, Chuanfei; Hara, Takuya; Jakosky, Bruce M.</p> <p>2017-04-01</p> <p>MAVEN observations have revealed an unexpectedly complex <span class="hlt">magnetic</span> field configuration in the magnetotail of Mars. This planetary magnetotail forms as the solar wind interacts with the Martian upper atmosphere and the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) drapes around the planet. This interaction is classically defined as an induced magnetosphere similar to the plasma environments of Venus and comets. However, unlike at these induced <span class="hlt">magnetic</span> environments, Mars is complicated by the existence of crustal <span class="hlt">magnetic</span> fields, which are able to reconnect with the IMF to produce open <span class="hlt">magnetic</span> fields. Preliminary magnetohydrodynamic simulation results have suggested that this <span class="hlt">magnetic</span> reconnection may be responsible for creating a hybrid magnetotail configuration between intrinsic and induced magnetospheres. This hybrid tail is composed of the closed planetary fields, draped IMF, and two distinct lobes of open <span class="hlt">magnetic</span> fields. More importantly, these open lobes appear to be twisted by roughly 45°, either clockwise or counterclockwise, from the ecliptic plane with a strong dependence on the east-west component of the IMF and negligible influence from crustal field orientation. To explore this unexpected twisted-tail configuration, we analyze MAVEN Magnetometer (MAG) and Solar Wind Ion Analyzer (SWIA) data to examine <span class="hlt">magnetic</span> field topology in the Martian magnetotail. We compare the <span class="hlt">average</span> <span class="hlt">magnetic</span> field orientation, directed toward and away from the planet, for a variety of solar wind parameters at various downtail distances. We conclude that the east-west IMF component strongly affects the magnetotail structure, as predicted by simulations. Furthermore, these data reveal that the tail lobes are indeed twisted, which we infer based on model results, to be regions of open <span class="hlt">magnetic</span> fields that are likely reconnected crustal fields. These MAVEN observations confirm that the Martian magnetotail has a hybrid configuration between an intrinsic and induced magnetosphere, shifting</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840031228&hterms=deutsche+forschungsgemeinschaft&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Ddeutsche%2Bforschungsgemeinschaft','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840031228&hterms=deutsche+forschungsgemeinschaft&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Ddeutsche%2Bforschungsgemeinschaft"><span>A case study of the response of the magnetosphere to changes in the <span class="hlt">interplanetary</span> medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rostoker, G.; Baumjohann, W.; Russell, C. T.</p> <p>1983-01-01</p> <p>A detailed analysis of world-wide ground based magnetometer data is presented, together with information on the plasma and <span class="hlt">magnetic</span> field properties of the <span class="hlt">interplanetary</span> medium and magnetosheath obtained from the ISEE 1 and 2 and IMP 8 spacecraft. The event concerned exhibited an interval of relatively stable southward IMF followed by a sharp northward turning. It is pointed out that during the interval of southward IMF there were occasional transient northward turnings with significant substorm expansive phase activity appearing to be triggered by these transient northward turnings. The final northward turning of the IMF was linked with an episode of strong magnetospheric substorm expansive phase activity after which the level of high latitude <span class="hlt">magnetic</span> activity declined to a low level. Evidence is presented indicating that the driven system auroral electrojets begin to decay at the time of the northward turning of the IMF, even as the substorm expansive phase activity is initiated in the midnight sector. The collapse of the substorm current wedge during the final decay of high latitude activity is described in some detail, and it is shown that this collapse occurs progressively from east to west in a series of impulsive episodes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38.2017Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38.2017Z"><span>Energetic electrons response to ULF waves induced by <span class="hlt">interplanetary</span> shocks in the outer radiation belt</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zong, Qiugang</p> <p></p> <p>Strong <span class="hlt">interplanetary</span> shocks interaction with the Earth's magnetosphere would have great impacts on the Earth's magnetosphere. Cluster and Double Star constellation provides an ex-cellent opportunity to study the inner magnetospheric response to a powerful <span class="hlt">interplanetary</span> solar wind forcing. An <span class="hlt">interplanetary</span> shock on Nov.7 2004 with the solar wind dynamic pres-sure ˜ 70 nPa (Maximum) induced a large bipolar electric field in the plasmasphere boundary layer as observed by Cluster fleet, the peak-to-peak ∆Ey is more than 60 mV/m. Energetic elec-trons in the outer radiation belt are accelerated almost simultaneously when the <span class="hlt">interplanetary</span> shock impinges upon the Earth's magnetosphere. Energetic electron bursts are coincident with the induced large electric field, energetic electrons (30 to 500 keV) with 900 pitch angles are accelerated first whereas those electrons are decelerated when the shock-induced electric field turns to positive value. Both toroidal and poloidal mode waves are found to be important but interacting with energetic electron at a different L-shell and a different period. At the Cluster's position (L = 4.4,), poloidal is predominant wave mode whereas at the geosynchronous orbits (L = 6.6), the ULF waves observed by the GOES -10 and -12 satellites are mostly toroidal. For comparison, a rather weak <span class="hlt">interplanetary</span> shock on Aug. 30, 2001 (dynamic pressure ˜ 2.7 nPa) is also investigated in this paper. It is found that <span class="hlt">interplanetary</span> shocks or solar wind pressure pulses with even small dynamic pressure change would have non-ignorable role in the radiation belt dynamic. Further, in this paper, our results also reveal the excitation of ULF waves re-sponses on the passing <span class="hlt">interplanetary</span> shock, especially the importance of difference ULF wave modes when interacting with the energetic electrons in the radiation belt. The damping of the shock induced ULF waves could be separated into two terms: one term corresponds to the generalized Landau damping, the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770023199','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770023199"><span>Research in space science and technology. [including X-ray astronomy and <span class="hlt">interplanetary</span> plasma physics</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Beckley, L. E.</p> <p>1977-01-01</p> <p>Progress in various space flight research programs is reported. Emphasis is placed on X-ray astronomy and <span class="hlt">interplanetary</span> plasma physics. Topics covered include: infrared astronomy, long base line interferometry, geological spectroscopy, space life science experiments, atmospheric physics, and space based materials and structures research. Analysis of galactic and extra-galactic X-ray data from the Small Astronomy Satellite (SAS-3) and HEAO-A and <span class="hlt">interplanetary</span> plasma data for Mariner 10, Explorers 47 and 50, and Solrad is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH53A2539L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH53A2539L"><span>Predicting ICME properties at 1AU</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lago, A.; Braga, C. R.; Mesquita, A. L.; De Mendonça, R. R. S.</p> <p>2017-12-01</p> <p>Coronal mass ejections (CMEs) are among the main origins of geomagnetic disturbances. They change the properties of the near-earth <span class="hlt">interplanetary</span> medium, enhancing some key parameters, such as the southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and the solar wind speed. Both quantities are known to be related to the energy transfer from the solar wind to the Earth's magnetosphere via the <span class="hlt">magnetic</span> reconnection process. Many attempts have been made to predict the <span class="hlt">magnetic</span> filed and the solar wind speed from coronagraph observations. However, we still have much to learn about the dynamic evolution of ICMEs as they propagate through the <span class="hlt">interplanetary</span> space. Increased observation capability is probably needed. Among the several attempts to establish correlations between CME and ICME properties, it was found that the <span class="hlt">average</span> CME propagation speed to 1AU is highly correlated to the ICME peak speed (Dal Lago et al, 2004). In this work, we present an extended study of such correlation, which confirms the results found in our previous study. Some suggestions on how to use this kind of results for space weather estimates are explored.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009SPIE.7385E..0XY','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009SPIE.7385E..0XY"><span>The use of x-ray pulsar-based navigation method for <span class="hlt">interplanetary</span> flight</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Bo; Guo, Xingcan; Yang, Yong</p> <p>2009-07-01</p> <p>As <span class="hlt">interplanetary</span> missions are increasingly complex, the existing unique mature <span class="hlt">interplanetary</span> navigation method mainly based on radiometric tracking techniques of Deep Space Network can not meet the rising demands of autonomous real-time navigation. This paper studied the applications for <span class="hlt">interplanetary</span> flights of a new navigation technology under rapid development-the X-ray pulsar-based navigation for spacecraft (XPNAV), and valued its performance with a computer simulation. The XPNAV is an excellent autonomous real-time navigation method, and can provide comprehensive navigation information, including position, velocity, attitude, attitude rate and time. In the paper the fundamental principles and time transformation of the XPNAV were analyzed, and then the Delta-correction XPNAV blending the vehicles' trajectory dynamics with the pulse time-of-arrival differences at nominal and estimated spacecraft locations within an Unscented Kalman Filter (UKF) was discussed with a background mission of Mars Pathfinder during the heliocentric transferring orbit. The XPNAV has an intractable problem of integer pulse phase cycle ambiguities similar to the GPS carrier phase navigation. This article innovatively proposed the non-ambiguity assumption approach based on an analysis of the search space array method to resolve pulse phase cycle ambiguities between the nominal position and estimated position of the spacecraft. The simulation results show that the search space array method are computationally intensive and require long processing time when the position errors are large, and the non-ambiguity assumption method can solve ambiguity problem quickly and reliably. It is deemed that autonomous real-time integrated navigation system of the XPNAV blending with DSN, celestial navigation, inertial navigation and so on will be the development direction of <span class="hlt">interplanetary</span> flight navigation system in the future.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005JGRA..110.4201V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005JGRA..110.4201V"><span>Solar, <span class="hlt">interplanetary</span>, and magnetospheric parameters for the radiation belt energetic electron flux</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vassiliadis, D.; Fung, S. F.; Klimas, A. J.</p> <p>2005-04-01</p> <p>In developing models of the radiation belt energetic electron flux, it is important to include the states of the <span class="hlt">interplanetary</span> medium and the magnetosphere, as well as the solar activity. In this study we choose the log flux je(t;L;E) at 2-6 MeV, as measured by the Proton-Electron Telescope (PET) on SAMPEX in the period 1993-2002, as a representative flux variable and evaluate the usefulness of 17 <span class="hlt">interplanetary</span> and magnetospheric (IP/MS) parameters in its specification. The reference parameter is the solar wind velocity, chosen because of its known high geoeffectiveness. We use finite impulse response filters to represent the effective coupling of the individual parameters to the log flux. We measure the temporal and spatial scales of the coupling using the impulse response function and the input's geoeffectiveness using the data-model correlation. The correlation profile as a function of L is complex, and we identify its peaks in reference to the radial regions P0 (L = 3.1-4.0, inner edge of the outer belt), P1 (4.1-7.5, main outer belt), and P2 (>7.5, quasi-trapped population), whose boundaries are determined from a radial correlative analysis (Vassiliadis et al., 2003b). Using the profiles, we classify the IP/MS parameters in four categories: (1) For the solar wind velocity and pressure the correlation is high and largely independent of L across P0 and P1, reaching its maximum in L = 4.8-6.1, or the central part of P1. (2) The IMF BSouth component and related IP/MS parameters have a bimodal correlation function, with peaks in region P0 (L = 3.0-4.1) and the geosynchronous orbit region within P1. (3) The IMF BNorth and four other <span class="hlt">interplanetary</span> or solar irradiance parameters have a minimum correlation in P1, while the highest correlation is in the slot-outer belt boundary (L = 2.5). (4) Finally, the solar wind density has a unique correlation profile, which is anticorrelated with that of the solar wind velocity for certain L shells. We verify this</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AnGeo..26.2937C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AnGeo..26.2937C"><span>The effects of an <span class="hlt">interplanetary</span> shock on the high-latitude ionospheric convection during an IMF By-dominated period</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Coco, I.; Amata, E.; Marcucci, M. F.; Ambrosino, D.; Villain, J.-P.; Hanuise, C.</p> <p>2008-09-01</p> <p>On 6 January 1998 an <span class="hlt">interplanetary</span> shock hit the magnetosphere around 14:15 UT and caused a reconfiguration of the northern high-latitude ionospheric convection. We use SuperDARN, spacecraft and ground magnetometer data to study such reconfiguration. We find that the shock front was tilted towards the morning flank of the magnetosphere, while the <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field (IMF) was By-dominated, with By<0, IMF Bz>0 and |By|>>Bz. As expected, the magnetospheric compression started at the first impact point of the shock on the magnetopause causing an increase of the Chapman-Ferraro current from dawn to dusk and yielding an increase of the geomagnetic field at the geostationary orbit and on the ground. Moreover, the high-latitude magnetometer data show vortical structures clearly related to the interaction of the shock with the magnetosphere-ionosphere system. In this context, the SuperDARN convection maps show that at very high latitudes above the northern Cusp and in the morning sector, intense sunward convection fluxes appear, well correlated in time with the SI arrival, having a signature typical for Bz>0 dominated lobe reconnection. We suggest that in this case the dynamic pressure increase associated to the shock plays a role in favouring the setting up of a new lobe merging line albeit |By|>>Bz≥0.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012PhDT.......113C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012PhDT.......113C"><span>Autonomous <span class="hlt">interplanetary</span> constellation design</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chow, Cornelius Channing, II</p> <p></p> <p>According to NASA's integrated space technology roadmaps, space-based infrastructures are envisioned as necessary ingredients to a sustained effort in continuing space exploration. Whether it be for extra-terrestrial habitats, roving/cargo vehicles, or space tourism, autonomous space networks will provide a vital communications lifeline for both future robotic and human missions alike. Projecting that the Moon will be a bustling hub of activity within a few decades, a near-term opportunity for in-situ infrastructure development is within reach. This dissertation addresses the anticipated need for in-space infrastructure by investigating a general design methodology for autonomous <span class="hlt">interplanetary</span> constellations; to illustrate the theory, this manuscript presents results from an application to the Earth-Moon neighborhood. The constellation design methodology is formulated as an optimization problem, involving a trajectory design step followed by a spacecraft placement sequence. Modeling the dynamics as a restricted 3-body problem, the investigated design space consists of families of periodic orbits which play host to the constellations, punctuated by arrangements of spacecraft autonomously guided by a navigation strategy called LiAISON (Linked Autonomous <span class="hlt">Interplanetary</span> Satellite Orbit Navigation). Instead of more traditional exhaustive search methods, a numerical continuation approach is implemented to map the admissible configuration space. In particular, Keller's pseudo-arclength technique is used to follow folding/bifurcating solution manifolds, which are otherwise inaccessible with other parameter continuation schemes. A succinct characterization of the underlying structure of the local, as well as global, extrema is thus achievable with little a priori intuition of the solution space. Furthermore, the proposed design methodology offers benefits in computation speed plus the ability to handle mildly stochastic systems. An application of the constellation design</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150002546','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150002546"><span>Development and Transition of the Radiation, <span class="hlt">Interplanetary</span> Shocks, and Coronal Sources (RISCS) Toolset</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spann, James F.; Zank, G.</p> <p>2014-01-01</p> <p>We outline a plan to develop and transition a physics based predictive toolset called The Radiation, <span class="hlt">Interplanetary</span> Shocks, and Coronal Sources (RISCS) to describe the <span class="hlt">interplanetary</span> energetic particle and radiation environment throughout the inner heliosphere, including at the Earth. To forecast and "nowcast" the radiation environment requires the fusing of three components: 1) the ability to provide probabilities for incipient solar activity; 2) the use of these probabilities and daily coronal and solar wind observations to model the 3D spatial and temporal heliosphere, including <span class="hlt">magnetic</span> field structure and transients, within 10 Astronomical Units; and 3) the ability to model the acceleration and transport of energetic particles based on current and anticipated coronal and heliospheric conditions. We describe how to address 1) - 3) based on our existing, well developed, and validated codes and models. The goal of RISCS toolset is to provide an operational forecast and "nowcast" capability that will a) predict solar energetic particle (SEP) intensities; b) spectra for protons and heavy ions; c) predict maximum energies and their duration; d) SEP composition; e) cosmic ray intensities, and f) plasma parameters, including shock arrival times, strength and obliquity at any given heliospheric location and time. The toolset would have a 72 hour predicative capability, with associated probabilistic bounds, that would be updated hourly thereafter to improve the predicted event(s) and reduce the associated probability bounds. The RISCS toolset would be highly adaptable and portable, capable of running on a variety of platforms to accommodate various operational needs and requirements. The described transition plan is based on a well established approach developed in the Earth Science discipline that ensures that the customer has a tool that meets their needs</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AstPo...6...95H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AstPo...6...95H"><span>Problems of <span class="hlt">Interplanetary</span> and Interstellar Trade</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hickman, John</p> <p>2008-01-01</p> <p>If and when <span class="hlt">interplanetary</span> and interstellar trade develops, it will be novel in two respects. First, the distances and time spans involved will reduce all or nearly all trade to the exchange of intangible goods. That threatens the possibility of conducting business in a genuinely common currency and of enforcing debt agreements, especially those involving sovereign debt. Second, interstellar trade suggests trade between humans and aliens. Cultural distance is a probable obstacle to initiating and sustaining such trade. Such exchange also threatens the release of new and potentially toxic memes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/servlets/purl/869326','DOE-PATENT-XML'); return false;" href="https://www.osti.gov/servlets/purl/869326"><span>High <span class="hlt">average</span> power <span class="hlt">magnetic</span> modulator for metal vapor lasers</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Ball, Don G.; Birx, Daniel L.; Cook, Edward G.; Miller, John L.</p> <p>1994-01-01</p> <p>A three-stage <span class="hlt">magnetic</span> modulator utilizing <span class="hlt">magnetic</span> pulse compression designed to provide a 60 kV pulse to a copper vapor laser at a 4.5 kHz repetition rate is disclosed. This modulator operates at 34 kW input power. The circuit includes a step up auto transformer and utilizes a rod and plate stack construction technique to achieve a high packing factor.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRA..120.5805F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRA..120.5805F"><span>Interhemispheric differences in ionospheric convection: Cluster EDI observations revisited</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Förster, M.; Haaland, S.</p> <p>2015-07-01</p> <p>The interaction between the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and the geomagnetic field sets up a large-scale circulation in the magnetosphere. This circulation is also reflected in the <span class="hlt">magnetically</span> connected ionosphere. In this paper, we present a study of ionospheric convection based on Cluster Electron Drift Instrument (EDI) satellite measurements covering both hemispheres and obtained over a full solar cycle. The results from this study show that <span class="hlt">average</span> flow patterns and polar cap potentials for a given orientation of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field can be very different in the two hemispheres. In particular during southward directed <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field conditions, and thus enhanced energy input from the solar wind, the measurements show that the southern polar cap has a higher cross polar cap potential. There are persistent north-south asymmetries, which cannot easily be explained by the influence of external drivers. These persistent asymmetries are primarily a result of the significant differences in the strength and configuration of the geomagnetic field between the Northern and Southern Hemispheres. Since the ionosphere is <span class="hlt">magnetically</span> connected to the magnetosphere, this difference will also be reflected in the magnetosphere in the form of different feedback from the two hemispheres. Consequently, local ionospheric conditions and the geomagnetic field configuration are important for north-south asymmetries in large regions of geospace.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH31D..08R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH31D..08R"><span>Predicting the <span class="hlt">Magnetic</span> Properties of ICMEs: A Pragmatic View</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Riley, P.; Linker, J.; Ben-Nun, M.; Torok, T.; Ulrich, R. K.; Russell, C. T.; Lai, H.; de Koning, C. A.; Pizzo, V. J.; Liu, Y.; Hoeksema, J. T.</p> <p>2017-12-01</p> <p>The southward component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field plays a crucial role in being able to successfully predict space weather phenomena. Yet, thus far, it has proven extremely difficult to forecast with any degree of accuracy. In this presentation, we describe an empirically-based modeling framework for estimating Bz values during the passage of <span class="hlt">interplanetary</span> coronal mass ejections (ICMEs). The model includes: (1) an empirically-based estimate of the <span class="hlt">magnetic</span> properties of the flux rope in the low corona (including helicity and field strength); (2) an empirically-based estimate of the dynamic properties of the flux rope in the high corona (including direction, speed, and mass); and (3) a physics-based estimate of the evolution of the flux rope during its passage to 1 AU driven by the output from (1) and (2). We compare model output with observations for a selection of events to estimate the accuracy of this approach. Importantly, we pay specific attention to the uncertainties introduced by the components within the framework, separating intrinsic limitations from those that can be improved upon, either by better observations or more sophisticated modeling. Our analysis suggests that current observations/modeling are insufficient for this empirically-based framework to provide reliable and actionable prediction of the <span class="hlt">magnetic</span> properties of ICMEs. We suggest several paths that may lead to better forecasts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040171195','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040171195"><span>Identification of <span class="hlt">Interplanetary</span> Coronal Mass Ejections at 1 AU Using Multiple Solar Wind Plasma Composition Anomalies</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, I. G.; Cane, H. V.</p> <p>2004-01-01</p> <p>We investigate the use of multiple simultaneous solar wind plasma compositional anomalies, relative to the composition of the ambient solar wind, for identifying <span class="hlt">interplanetary</span> coronal mass ejection (ICME) plasma. We first summarize the characteristics of several solar wind plasma composition signatures (O(+7)/O(+6), Mg/O, Ne/O, Fe charge states, He/p) observed by the ACE and WIND spacecraft within the ICMEs during 1996 - 2002 identsed by Cane and Richardson. We then develop a set of simple criteria that may be used to identify such compositional anomalies, and hence potential ICMEs. To distinguish these anomalies from the normal variations seen in ambient solar wind composition, which depend on the wind speed, we compare observed compositional signatures with those 'expected' in ambient solar wind with the same solar wind speed. This method identifies anomalies more effectively than the use of fixed thresholds. The occurrence rates of individual composition anomalies within ICMEs range from approx. 70% for enhanced iron and oxygen charge states to approx. 30% for enhanced He/p (> 0.06) and Ne/O, and are generally higher in <span class="hlt">magnetic</span> clouds than other ICMEs. Intervals of multiple anomalies are usually associated with ICMEs, and provide a basis for the identification of the majority of ICMEs. We estimate that Cane and Richardson, who did not refer to composition data, probably identitied approx. 90% of the ICMEs present. However, around 10% of their ICMEs have weak compositional anomalies, suggesting that the presence of such signatures does not provide a necessary requirement for an ICME. We note a remarkably similar correlation between the Mg/O and O(7)/O(6) ratios in hourly-<span class="hlt">averaged</span> data both within ICMEs and the ambient solar wind. This 'universal' relationship suggests that a similar process (such as minor ion heating by waves inside coronal <span class="hlt">magnetic</span> field loops) produces the first-ionization potential bias and ion freezing-in temperatures in the source regions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000065622','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000065622"><span><span class="hlt">Magnetic</span> Flux Compression Concept for Aerospace Propulsion and Power</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Litchford, Ron J.; Robertson, Tony; Hawk, Clark W.; Turner, Matt; Koelfgen, Syri</p> <p>2000-01-01</p> <p>The objective of this research is to investigate system level performance and design issues associated with <span class="hlt">magnetic</span> flux compression devices for aerospace power generation and propulsion. The proposed concept incorporates the principles of <span class="hlt">magnetic</span> flux compression for direct conversion of nuclear/chemical detonation energy into electrical power. Specifically a <span class="hlt">magnetic</span> field is compressed between an expanding detonation driven diamagnetic plasma and a stator structure formed from a high temperature superconductor (HTSC). The expanding plasma cloud is entirely confined by the compressed <span class="hlt">magnetic</span> field at the expense of internal kinetic energy. Electrical power is inductively extracted, and the detonation products are collimated and expelled through a <span class="hlt">magnetic</span> nozzle. The long-term development of this highly integrated generator/propulsion system opens up revolutionary NASA Mission scenarios for future <span class="hlt">interplanetary</span> and interstellar spacecraft. The unique features of this concept with respect to future space travel opportunities are as follows: ability to implement high energy density chemical detonations or ICF microfusion bursts as the impulsive diamagnetic plasma source; high power density system characteristics constrain the size, weight, and cost of the vehicle architecture; provides inductive storage pulse power with a very short pulse rise time; multimegajoule energy bursts/terawatt power bursts; compact pulse power driver for low-impedance dense plasma devices; utilization of low cost HTSC material and casting technology to increase <span class="hlt">magnetic</span> flux conservation and inductive energy storage; improvement in chemical/nuclear-to-electric energy conversion efficiency and the ability to generate significant levels of thrust with very high specific impulse; potential for developing a small, lightweight, low cost, self-excited integrated propulsion and power system suitable for space stations, planetary bases, and <span class="hlt">interplanetary</span> and interstellar space travel</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060029791&hterms=internet&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dinternet','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060029791&hterms=internet&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dinternet"><span>Towards an <span class="hlt">interplanetary</span> internet: a proposed strategy for standardization</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hooke, A. J.</p> <p>2002-01-01</p> <p>This paper reviews the current set of standard data communications capabilities that exist to support advanced missions, discusses the architectural concepts for the future <span class="hlt">Interplanetary</span> Internet, and suggests how a standardized set of space communications protocols that can grow to support future scenarios where human intelligence is widely distributed across the Solar System.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780019090','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780019090"><span>Research in space physics at the University of Iowa. [energetic particles and electric, <span class="hlt">magnetic</span>, and electromagnetic fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Vanallen, J. A.</p> <p>1978-01-01</p> <p>Specific fields of current investigation by satellite observation and ground-based radio-astronomical and optical techniques are discussed. Topics include: aspects of energetic particles trapped in the earth's <span class="hlt">magnetic</span> field and transiently present in the outer magnetosphere and the solar, <span class="hlt">interplanetary</span>, and terrestrial phenomena associated with them; plasma flows in the magnetosphere and the ionospheric effects of particle precipitation, with corresponding studies of the magnetosphere of Jupiter, Saturn, and possibly Uranus; the origin and propagation of very low frequency radio waves in the earth's magnetosphere and ionosphere; solar particle emissions and their <span class="hlt">interplanetary</span> propagation and acceleration; solar modulation and the heliocentric radial dependence of the intensity of galactic cosmic rays; radio frequency emissions from the quintescent and flaring sun; shock waves in the <span class="hlt">interplanetary</span> medium; radio emissions from Jupiter; and radio astronomy of pulsars, flare stars, and other stellar sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMSH53A2137C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMSH53A2137C"><span>Ring current-energy balance during intense <span class="hlt">magnetic</span> storms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clua de Gonzalez, A. L.; Gonzalez, W. D.</p> <p>2013-12-01</p> <p>The energy-rate balance that governs the storm-time ring current is analyzed in terms of the Burton-McPherron-Russell equation (Burton et al., 1975). This is a first order differential equation relating the time variation of the pressure corrected Dst index, with the energy input to the magnetosphere. Based on the Burton et al. equation, we have analyzed in detail the geomagnetic storm of February 11, 2004. The energy input is taken proportional to the <span class="hlt">interplanetary</span> electric field, Q(t) = αBsV, where Bs is the southward component of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field in GSM coordinates, V is the flow speed of the solar wind and α a constant. The equation is integrated using the OMNI-combined <span class="hlt">interplanetary</span> data and, the value of the decay time is estimated from a best fit of the response to the observed curve. For this storm we also use a rectangular approximation for the energy input function, thus allowing an analytical solution of the Burton et al. equation. The results from this approximation are then compared to the numerical solution. The study is also extended to the geomagnetic storm of April 22, 2001. This analysis seems to indicate that the Burton et al. equation should contain also a corrective term proportional to the second time derivative of the Dst index. This corrective term might become important for intense storms, with an effect of counteracting the growth of |Dst| before the energy input from the <span class="hlt">interplanetary</span> medium declines, such that the value of |Dst| starts to decrease instead of continuing to grow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AcAau.139..102T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AcAau.139..102T"><span>Cultural ethology as a new approach of <span class="hlt">interplanetary</span> crew's behavior</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tafforin, Carole; Giner Abati, Francisco</p> <p>2017-10-01</p> <p>From an evolutionary perspective, during short-term and medium-term orbital flights, human beings developed new spatial and motor behaviors to compensate for the lack of terrestrial gravity. Past space ethological studies have shown adaptive strategies to the tri-dimensional environment, with the goal of optimizing relationships between the astronaut and unusual sensorial-motor conditions. During a long-term <span class="hlt">interplanetary</span> journey, crewmembers will have to develop new individual and social behaviors to adapt, far from earth, to isolation and confinement and as a result to extreme conditions of living and working together. Recent space psychological studies pointed out that heterogeneity is a feature of <span class="hlt">interplanetary</span> crews, based on personality, gender mixing, internationality and diversity of backgrounds. Intercultural issues could arise between space voyagers. As a new approach we propose to emphasize the behavioral strategies of human groups' adaptation to this new multicultural dimension of the environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830009164','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830009164"><span>Type 2 radio bursts, <span class="hlt">interplanetary</span> shocks and energetic particle events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cane, H. V.; Stone, R. G.</p> <p>1982-01-01</p> <p>Using the ISEE-3 radio astronomy experiment data 37 <span class="hlt">interplanetary</span> (IP) type II bursts have been identified in the period September 1978 to December 1981. These events and the associated phenomena are listed. The events are preceded by intense, soft X ray events with long decay times (LDEs) and type II and/or type IV bursts at meter wavelengths. The meter wavelength type II bursts are usually intense and exhibit herringbone structure. The extension of the herringbone structure into the kilometer wavelength range results in the occurrence of a shock accelerated (SA) event. The majority of the <span class="hlt">interplanetary</span> type II bursts are associated with energetic particle events. These results support other studies which indicate that energetic solar particles detected at 1 A.U. are generated by shock acceleration. From a preliminary analysis of the available data there appears to be a high correlation with white light coronal transients.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoRL..44.7643N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoRL..44.7643N"><span>Response of Jupiter's auroras to conditions in the <span class="hlt">interplanetary</span> medium as measured by the Hubble Space Telescope and Juno</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nichols, J. D.; Badman, S. V.; Bagenal, F.; Bolton, S. J.; Bonfond, B.; Bunce, E. J.; Clarke, J. T.; Connerney, J. E. P.; Cowley, S. W. H.; Ebert, R. W.; Fujimoto, M.; Gérard, J.-C.; Gladstone, G. R.; Grodent, D.; Kimura, T.; Kurth, W. S.; Mauk, B. H.; Murakami, G.; McComas, D. J.; Orton, G. S.; Radioti, A.; Stallard, T. S.; Tao, C.; Valek, P. W.; Wilson, R. J.; Yamazaki, A.; Yoshikawa, I.</p> <p>2017-08-01</p> <p>We present the first comparison of Jupiter's auroral morphology with an extended, continuous, and complete set of near-Jupiter <span class="hlt">interplanetary</span> data, revealing the response of Jupiter's auroras to the <span class="hlt">interplanetary</span> conditions. We show that for ˜1-3 days following compression region onset, the planet's main emission brightened. A duskside poleward region also brightened during compressions, as well as during shallow rarefaction conditions at the start of the program. The power emitted from the noon active region did not exhibit dependence on any <span class="hlt">interplanetary</span> parameter, though the morphology typically differed between rarefactions and compressions. The auroras equatorward of the main emission brightened over ˜10 days following an interval of increased volcanic activity on Io. These results show that the dependence of Jupiter's magnetosphere and auroras on the <span class="hlt">interplanetary</span> conditions are more diverse than previously thought.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900049938&hterms=SMM&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSMM','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900049938&hterms=SMM&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DSMM"><span>Solar wind and coronal structure near sunspot minimum - Pioneer and SMM observations from 1985-1987</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mihalov, J. D.; Barnes, A.; Hundhausen, A. J.; Smith, E. J.</p> <p>1990-01-01</p> <p>Changes in solar wind speed and <span class="hlt">magnetic</span> polarity observed at the Pioneer spacecraft are discussed here in terms of the changing <span class="hlt">magnetic</span> geometry implied by SMM coronagraph observations over the period 1985-1987. The pattern of recurrent solar wind streams, the long-term <span class="hlt">average</span> speed, and the sector polarity of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field all changed in a manner suggesting both a temporal variation, and a changing dependence on heliographic latitude. Coronal observations during this epoch show a systematic variation in coronal structure and the <span class="hlt">magnetic</span> structure imposed on the expanding solar wind. These observations suggest interpretation of the solar wind speed variations in terms of the familiar model where the speed increases with distance from a nearly flat <span class="hlt">interplanetary</span> current sheet, and where this current sheet becomes aligned with the solar equatorial plane as sunspot minimum approaches, but deviates rapidly from that orientation after minimum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20100015562&hterms=Total+Care&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DTotal%2BCare','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20100015562&hterms=Total+Care&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DTotal%2BCare"><span>Estimating Total Heliospheric <span class="hlt">Magnetic</span> Flux from Single-Point in Situ Measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Owens, M. J.; Arge, C. N.; Crooker, N. U.; Schwardron, N. A.; Horbury, T. S.</p> <p>2008-01-01</p> <p>A fraction of the total photospheric <span class="hlt">magnetic</span> flux opens to the heliosphere to form the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field carried by the solar wind. While this open flux is critical to our understanding of the generation and evolution of the solar <span class="hlt">magnetic</span> field, direct measurements are generally limited to single-point measurements taken in situ by heliospheric spacecraft. An observed latitude invariance in the radial component of the <span class="hlt">magnetic</span> field suggests that extrapolation from such single-point measurements to total heliospheric <span class="hlt">magnetic</span> flux is possible. In this study we test this assumption using estimates of total heliospheric flux from well-separated heliospheric spacecraft and conclude that single-point measurements are indeed adequate proxies for the total heliospheric <span class="hlt">magnetic</span> flux, though care must be taken when comparing flux estimates from data collected at different heliocentric distances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AcAau..67.1391R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AcAau..67.1391R"><span>The pioneers of <span class="hlt">interplanetary</span> communication: From Gauss to Tesla</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Raulin-Cerceau, Florence</p> <p>2010-12-01</p> <p>The present overview covers the period from 1820 to the beginning of the 20th century. Emphasis is laid on the latter half of the 19th century because many efforts have been done at that time to elaborate schemes for contacting our neighboring planets by <span class="hlt">interplanetary</span> telegraphy. This period knew many advances not only in planetary studies but also in the nascent field of telecommunications. Such a context led astronomers who were also interested in the problem of planetary habitability, to envisage that other planets could be contacted, especially the planet Mars. <span class="hlt">Interplanetary</span> communication using a celestial telegraphy was planned during this period of great speculations about life on Mars. This paper focuses on four authors: the Frenchmen C. Flammarion, Ch. Cros, A. Mercier and the Serbian N. Tesla, who formulated early proposals to communicate with Mars or Venus. The first proposals (which remained only theoretical) showed that an initial reflection had started as early as the second part of the 19th century on the type of language that could be both universal and distinguishable from a natural signal. Literary history of <span class="hlt">interplanetary</span> communication preceded by far the scientific one. Authors of the 1900s were very prolific on this topic. French fictions are mentioned in this paper as examples of such a literature. This incursion into selected texts stresses the fact that the problem of techniques and messages employed to communicate with other planets goes beyond the strict scientific framework. Finally, this paper aims to highlight the similarities as well as the differences between the different proposals and to underline what that could possibly help present SETI research to define messages supposed to be sent to other planetary systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22663351-prospective-out-ecliptic-white-light-imaging-interplanetary-corotating-interaction-regions-solar-maximum','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22663351-prospective-out-ecliptic-white-light-imaging-interplanetary-corotating-interaction-regions-solar-maximum"><span>Prospective Out-of-ecliptic White-light Imaging of <span class="hlt">Interplanetary</span> Corotating Interaction Regions at Solar Maximum</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Xiong, Ming; Yang, Liping; Liu, Ying D.</p> <p></p> <p><span class="hlt">Interplanetary</span> corotating interaction regions (CIRs) can be remotely imaged in white light (WL), as demonstrated by the Solar Mass Ejection Imager (SMEI) on board the Coriolis spacecraft and Heliospheric Imagers (HIs) on board the twin Solar TErrestrial RElations Observatory ( STEREO ) spacecraft. The <span class="hlt">interplanetary</span> WL intensity, due to Thomson scattering of incident sunlight by free electrons, is jointly determined by the 3D distribution of electron number density and line-of-sight (LOS) weighting factors of the Thomson-scattering geometry. The 2D radiance patterns of CIRs in WL sky maps look very different from different 3D viewpoints. Because of the in-ecliptic locations ofmore » both the STEREO and Coriolis spacecraft, the longitudinal dimension of <span class="hlt">interplanetary</span> CIRs has, up to now, always been integrated in WL imagery. To synthesize the WL radiance patterns of CIRs from an out-of-ecliptic (OOE) vantage point, we perform forward magnetohydrodynamic modeling of the 3D inner heliosphere during Carrington Rotation CR1967 at solar maximum. The mixing effects associated with viewing 3D CIRs are significantly minimized from an OOE viewpoint. Our forward modeling results demonstrate that OOE WL imaging from a latitude greater than 60° can (1) enable the garden-hose spiral morphology of CIRs to be readily resolved, (2) enable multiple coexisting CIRs to be differentiated, and (3) enable the continuous tracing of any <span class="hlt">interplanetary</span> CIR back toward its coronal source. In particular, an OOE view in WL can reveal where nascent CIRs are formed in the extended corona and how these CIRs develop in <span class="hlt">interplanetary</span> space. Therefore, a panoramic view from a suite of wide-field WL imagers in a solar polar orbit would be invaluable in unambiguously resolving the large-scale longitudinal structure of CIRs in the 3D inner heliosphere.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApJ...844...76X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApJ...844...76X"><span>Prospective Out-of-ecliptic White-light Imaging of <span class="hlt">Interplanetary</span> Corotating Interaction Regions at Solar Maximum</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xiong, Ming; Davies, Jackie A.; Li, Bo; Yang, Liping; Liu, Ying D.; Xia, Lidong; Harrison, Richard A.; Keiji, Hayashi; Li, Huichao</p> <p>2017-07-01</p> <p><span class="hlt">Interplanetary</span> corotating interaction regions (CIRs) can be remotely imaged in white light (WL), as demonstrated by the Solar Mass Ejection Imager (SMEI) on board the Coriolis spacecraft and Heliospheric Imagers (HIs) on board the twin Solar TErrestrial RElations Observatory (STEREO) spacecraft. The <span class="hlt">interplanetary</span> WL intensity, due to Thomson scattering of incident sunlight by free electrons, is jointly determined by the 3D distribution of electron number density and line-of-sight (LOS) weighting factors of the Thomson-scattering geometry. The 2D radiance patterns of CIRs in WL sky maps look very different from different 3D viewpoints. Because of the in-ecliptic locations of both the STEREO and Coriolis spacecraft, the longitudinal dimension of <span class="hlt">interplanetary</span> CIRs has, up to now, always been integrated in WL imagery. To synthesize the WL radiance patterns of CIRs from an out-of-ecliptic (OOE) vantage point, we perform forward magnetohydrodynamic modeling of the 3D inner heliosphere during Carrington Rotation CR1967 at solar maximum. The mixing effects associated with viewing 3D CIRs are significantly minimized from an OOE viewpoint. Our forward modeling results demonstrate that OOE WL imaging from a latitude greater than 60° can (1) enable the garden-hose spiral morphology of CIRs to be readily resolved, (2) enable multiple coexisting CIRs to be differentiated, and (3) enable the continuous tracing of any <span class="hlt">interplanetary</span> CIR back toward its coronal source. In particular, an OOE view in WL can reveal where nascent CIRs are formed in the extended corona and how these CIRs develop in <span class="hlt">interplanetary</span> space. Therefore, a panoramic view from a suite of wide-field WL imagers in a solar polar orbit would be invaluable in unambiguously resolving the large-scale longitudinal structure of CIRs in the 3D inner heliosphere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.8502W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.8502W"><span>Linear response of field-aligned currents to the <span class="hlt">interplanetary</span> electric field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weimer, D. R.; Edwards, T. R.; Olsen, Nils</p> <p>2017-08-01</p> <p>Many studies that have shown that the ionospheric, polar cap electric potentials (PCEPs) exhibit a "saturation" behavior in response to the level of the driving by the solar wind. As the magnitudes of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) and electric field (IEF) increase, the PCEP response is linear at low driving levels, followed with a rollover to a more constant level. While there are several different theoretical explanations for this behavior, so far, no direct observational evidence has existed to confirm any particular model. In most models of this saturation, the interaction of the field-aligned currents (FACs) with the solar wind/magnetosphere/ionosphere system has a role. As the FACs are more difficult to measure, their behavior in response to the level of the IEF has not been investigated as thoroughly. In order to resolve the question of whether or not the FAC also exhibit saturation, we have processed the <span class="hlt">magnetic</span> field measurements from the Ørsted, CHAMP, and Swarm missions, spanning more than a decade. As the amount of current in each region needs to be known, a new technique is used to separate and sum the current by region, widely known as R0, R1, and R2. These totals are found separately for the dawnside and duskside. Results indicate that the total FAC has a response to the IEF that is highly linear, continuing to increase well beyond the level at which the electric potentials saturate. The currents within each region have similar behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH51A2480G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH51A2480G"><span>STEREO observations of insitu waves in the vicinity of <span class="hlt">interplanetary</span> shocks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Golla, T.; MacDowall, R. J.</p> <p>2017-12-01</p> <p>We present the high time resolution observations of the in situ waves obtained by the time domain sampler (TDS) of the WAVES experiment on the STEREO spacecraft in the vicinity of typical quasi-perpendicular super-critical <span class="hlt">interplanetary</span> shocks. We show that often Langmuir waves occur as coherent one dimensional <span class="hlt">magnetic</span> field aligned wave packets in the upstream regions and persist over large distances. The characteristics of these wave packets are consistent with those of Langmuir solitons formed as a result of oscillatting two stream instability (OTSI). Very intense high frequency waves which are completely different from Langmuir waves occur in the transition regions. These waves occur as very incoherent emissions and exhibit broad fundamental and second harmonic spectral peaks. We identify these waves as electron acoustic waves excited by the electron beams in the transition regions. We also show that very intense low frequency ion sound waves occur in the downstream regions. We discuss the implications of these observations on the theories of (1) strong Langmuir turbulence, (2) beam stabilization, (3) emission mechanisms of solar type II radio bursts, (4) wave-particle interactions responsible for collisionless dissipation, and (5) heating of the downstream plasmas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19720006153&hterms=theory+relativity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtheory%2Brelativity','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19720006153&hterms=theory+relativity&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D90%26Ntt%3Dtheory%2Brelativity"><span>Applications of presently planned <span class="hlt">interplanetary</span> missions to testing gravitational theories</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Friedman, L. D.</p> <p>1971-01-01</p> <p>A summary of the probable <span class="hlt">interplanetary</span> missions for the 1970's is presented, which may prove useful in testing the general theory of relativity. Mission characteristics are discussed, as well as instrumentation. This last includes a low-level accelerometer and S-/X-band transponders and antennas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950004531','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950004531"><span>Workshop on the Analysis of <span class="hlt">Interplanetary</span> Dust Particles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zolensky, Michael E. (Editor)</p> <p>1994-01-01</p> <p>Great progress has been made in the analysis of <span class="hlt">interplanetary</span> dust particles (IDP's) over the past few years. This workshop provided a forum for the discussion of the following topics: observation and modeling of dust in the solar system, mineralogy and petrography of IDP's, processing of IDP's in the solar system and terrestrial atmosphere, comparison of IDP's to meteorites and micrometeorites, composition of IDP's, classification, and collection of IDP's.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1998ATel...19....1H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1998ATel...19....1H"><span>3rd <span class="hlt">Interplanetary</span> Network Gamma-Ray Burst Website</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hurley, Kevin</p> <p>1998-05-01</p> <p>We announce the opening of the 3rd <span class="hlt">Interplanetary</span> Network web site at http://ssl.berkeley.edu/ipn3/index.html This site presently has four parts: 1. A bibliography of over 3000 publications on gamma-ray bursts, 2. IPN data on all bursts triangulated up to February 1998, 3. A master list showing which spacecraft observed which bursts, 4. Preliminary IPN data on the latest bursts observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900004862','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900004862"><span>Shear-induced inflation of coronal <span class="hlt">magnetic</span> fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Klimchuk, James A.</p> <p>1989-01-01</p> <p>Using numerical models of force-free <span class="hlt">magnetic</span> fields, the shearing of footprints in arcade geometries leading to an inflation of the coronal <span class="hlt">magnetic</span> field was examined. For each of the shear profiles considered, all of the field lines become elevated compared with the potential field. This includes cases where the shear is concentrated well away from the arcade axis, such that B(sub z), the component of field parallel to the axis, increases outward to produce an inward B(sub z)squared/8 pi <span class="hlt">magnetic</span> pressure gradient force. These results contrast with an earlier claim, shown to be incorrect, that field lines can sometimes become depressed as a result of shear. It is conjectured that an inflation of the entire field will always result from the shearing of simple arcade configurations. These results have implications for prominence formation, the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> flux, and possibly also coronal holes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900047481&hterms=inflation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dinflation','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900047481&hterms=inflation&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dinflation"><span>Shear-induced inflation of coronal <span class="hlt">magnetic</span> fields</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Klimchuk, James A.</p> <p>1990-01-01</p> <p>Using numerical models of force-free <span class="hlt">magnetic</span> fields, the shearing of footprints in arcade geometries leading to an inflation of the coronal <span class="hlt">magnetic</span> field was examined. For each of the shear profiles considered, all of the field lines become elevated compared with the potential field. This includes cases where the shear is concentrated well away from the arcade axis, such that B(sub z), the component of field parallel to the axis, increases outward to produce an inward B(sub z) squared/8 pi <span class="hlt">magnetic</span> pressure gradient force. These results contrast with an earlier claim, shown to be incorrect, that field lines can sometimes become depressed as a result of shear. It is conjectured that an inflation of the entire field will always result from the shearing of simple arcade configurations. These results have implications for prominence formation, the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> flux, and possibly also coronal holes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170008211&hterms=earth+system+modeling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dearth%2Bsystem%2Bmodeling','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170008211&hterms=earth+system+modeling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dearth%2Bsystem%2Bmodeling"><span>Integrated Vehicle and Trajectory Design of Small Spacecraft with Electric Propulsion for Earth and <span class="hlt">Interplanetary</span> Missions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spangelo, Sara; Dalle, Derek; Longmier, Benjamin</p> <p>2015-01-01</p> <p>This paper investigates the feasibility of Earth-transfer and <span class="hlt">interplanetary</span> mission architectures for miniaturized spacecraft using emerging small solar electric propulsion technologies. Emerging small SEP thrusters offer significant advantages relative to existing technologies and will enable U-class systems to perform trajectory maneuvers with significant Delta V requirements. The approach in this paper is unique because it integrates trajectory design with vehicle sizing and accounts for the system and operational constraints of small U-class missions. The modeling framework includes integrated propulsion, orbit, energy, and external environment dynamics and systems-level power, energy, mass, and volume constraints. The trajectory simulation environment models orbit boosts in Earth orbit and flyby and capture trajectories to <span class="hlt">interplanetary</span> destinations. A family of small spacecraft mission architectures are studied, including altitude and inclination transfers in Earth orbit and trajectories that escape Earth orbit and travel to <span class="hlt">interplanetary</span> destinations such as Mercury, Venus, and Mars. Results are presented visually to show the trade-offs between competing performance objectives such as maximizing available mass and volume for payloads and minimizing transfer time. The results demonstrate the feasibility of using small spacecraft to perform significant Earth and <span class="hlt">interplanetary</span> orbit transfers in less than one year with reasonable U-class mass, power, volume, and mission durations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940007787&hterms=Organic+mars&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DOrganic%2Bmars','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940007787&hterms=Organic+mars&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DOrganic%2Bmars"><span>Organic matter on the early surface of Mars: An assessment of the contribution by <span class="hlt">interplanetary</span> dust</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Flynn, G. J.</p> <p>1993-01-01</p> <p>Calculations by Anders and Chyba et al. have recently revived interest in the suggestion that organic compounds important to the development of life were delivered to the primitive surface of the Earth by comets, asteroids or the <span class="hlt">interplanetary</span> dust derived from these two sources. Anders has shown that the major post-accretion contribution of extraterrestrial organic matter to the surface of the Earth is from <span class="hlt">interplanetary</span> dust. Since Mars is a much more favorable site for the gentle deceleration of <span class="hlt">interplanetary</span> dust particles than is Earth, model calculations show that biologically important organic compounds are likely to have been delivered to the early surface of Mars by the <span class="hlt">interplanetary</span> dust in an order-of-magnitude higher surface density than onto the early Earth. Using the method described by Flynn and McKay, the size frequency distribution, and the atmospheric entry velocity distribution of IDP's at Mars were calculated. The entry velocity distribution, coupled with the atmospheric entry heating model developed by Whipple and extended by Fraundorf was used to calculate the fraction of the particles in each mass decade which survives atmospheric entry without melting (i.e., those not heated above 1600K). The incident mass and surviving mass in each mass decade are shown for both Earth and Mars.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19940033532&hterms=magnetic+particles&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmagnetic%2Bparticles','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19940033532&hterms=magnetic+particles&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmagnetic%2Bparticles"><span>Simultaneous observations of solar MeV particles in a <span class="hlt">magnetic</span> cloud and in the earth's northern tail lobe - Implications for the global field line topology of <span class="hlt">magnetic</span> clouds and for the entry of solar particles into the magnetosphere during cloud passage</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Farrugia, C. J.; Richardson, I. G.; Burlaga, L. F.; Lepping, R. P.; Osherovich, V. A.</p> <p>1993-01-01</p> <p>Simultaneous ISEE 3 and IMP 8 spacecraft observations of <span class="hlt">magnetic</span> fields and flow anisotropies of solar energetic protons and electrons during the passage of an <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> cloud show various particle signature differences at the two spacecraft. These differences are interpretable in terms of the <span class="hlt">magnetic</span> line topology of the cloud, the connectivity of the cloud field lines to the solar surface, and the interconnection between the <span class="hlt">magnetic</span> fields of the <span class="hlt">magnetic</span> clouds and of the earth. These observations are consistent with a <span class="hlt">magnetic</span> cloud model in which these mesoscale configurations are curved <span class="hlt">magnetic</span> flux ropes attached at both ends to the sun's surface, extending out to 1 AU.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19750052795&hterms=solar+pumping&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsolar%2Bpumping','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19750052795&hterms=solar+pumping&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dsolar%2Bpumping"><span>Measuring the <span class="hlt">magnetic</span> fields of Jupiter and the outer solar system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Smith, E. J.; Connor, B. V.; Foster, G. T., Jr.</p> <p>1975-01-01</p> <p>The vector helium magnetometer, one of the Pioneer-Jupiter experiments, has measured the <span class="hlt">magnetic</span> field of Jupiter and the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field in the outer solar system. The comprehensive scientific objectives of the investigations are explained and are then translated into the major instrument requirements. The principles of operation of the magnetometer, which involve the optical pumping of metastable helium, are discussed and the Pioneer instrument is described. The in-flight performance of the magnetometer is discussed and principal scientific results obtained thus far by the Pioneer investigation are summarized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19780016071','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19780016071"><span><span class="hlt">Interplanetary</span> propagation of flare-associated energetic particles</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Masung, L. L.; Earl, J. A.</p> <p>1978-01-01</p> <p>A propagation model which combines a Gaussian profile for particle release from the sun, with <span class="hlt">interplanetary</span> particle densities predicted by focused diffusion, was proposed to explain the propagation history of flare associated energetic particles. This model, which depends on only two parameters, successfully describes the time-intensity profiles of 30 proton and electron events originating from the western hemisphere of the sun. Generally, particles are released from the sun over a finite interval. In almost all events, particle release begins at the time of flare acceleration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850035588&hterms=monsanto&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dmonsanto','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850035588&hterms=monsanto&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dmonsanto"><span>Discovery of nuclear tracks in <span class="hlt">interplanetary</span> dust</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bradley, J. P.; Brownlee, D. E.; Fraundorf, P.</p> <p>1984-01-01</p> <p>Nuclear tracks have been identified in <span class="hlt">interplanetary</span> dust particles (IDP's) collected from the stratosphere. The presence of tracks unambiguously confirms the extraterrestrial nature of IDP's, and the high track densities (10 to the 10th to 10 to the 11th per square centimeter) suggest an exposure age of approximately 10,000 years within the inner solar system. Tracks also provide an upper temperature limit for the heating of IDP's during atmospheric entry, thereby making it possible to distinguish between pristine and thermally modified micrometeorites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19760020248','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19760020248"><span><span class="hlt">Magnetic</span> bearing reaction wheel. [for spacecraft attitude control</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sabnis, A.; Schmitt, F.; Smith, L.</p> <p>1976-01-01</p> <p>The results of a program for the development, fabrication and functional test of an engineering model <span class="hlt">magnetically</span> suspended reaction wheel are described. The reaction wheel develops an angular momentum of + or - 0.5 foot-pound-second and is intended for eventual application in the attitude control of long-life <span class="hlt">interplanetary</span> and orbiting spacecraft. A description of the wheel design and its major performance characteristics is presented. Recommendations for flight prototype development are made.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19820039098&hterms=magnetic+vector+potential&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmagnetic%2Bvector%2Bpotential','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19820039098&hterms=magnetic+vector+potential&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dmagnetic%2Bvector%2Bpotential"><span>Determination of <span class="hlt">magnetic</span> helicity in the solar wind and implications for cosmic ray propagation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Matthaeus, W. M.; Goldstein, M. L.</p> <p>1981-01-01</p> <p><span class="hlt">Magnetic</span> helicity (Hm) is the mean value of the correlation between a turbulent <span class="hlt">magnetic</span> field and the <span class="hlt">magnetic</span> vector potential. A technique is described for determining Hm and its 'reduced' spectrum from the two point <span class="hlt">magnetic</span> correlation matrix. The application of the derived formalism to solar wind <span class="hlt">magnetic</span> fluctuations is discussed, taking into account cases for which only single point measurements are available. The application procedure employs the usual 'frozen in approximation' approach. The considered method is applied to an analysis of several periods of Voyager 2 <span class="hlt">interplanetary</span> magnetometer data near 2.8 AU. During these periods the correlation length, or energy containing length, was found to be approximately 3 x 10 to the 11th cm</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730002044','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730002044"><span>Large-scale solar <span class="hlt">magnetic</span> fields and H-alpha patterns</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mcintosh, P. S.</p> <p>1972-01-01</p> <p>Coronal and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields computed from measurements of large-scale photospheric <span class="hlt">magnetic</span> fields suffer from interruptions in day-to-day observations and the limitation of using only measurements made near the solar central meridian. Procedures were devised for inferring the lines of polarity reversal from H-alpha solar patrol photographs that map the same large-scale features found on Mt. Wilson magnetograms. These features may be monitored without interruption by combining observations from the global network of observatories associated with NOAA's Space Environment Services Center. The patterns of inferred <span class="hlt">magnetic</span> fields may be followed accurately as far as 60 deg from central meridian. Such patterns will be used to improve predictions of coronal features during the next solar eclipse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900016720','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900016720"><span>The effect of <span class="hlt">interplanetary</span> trajectory options on a manned Mars aerobrake configuration</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Braun, Robert D.; Powell, Richard W.; Hartung, Lin C.</p> <p>1990-01-01</p> <p>Manned Mars missions originating in low Earth orbit (LEO) in the time frame 2010 to 2025 were analyzed to identify preferred mission opportunities and their associated vehicle and trajectory characteristics. <span class="hlt">Interplanetary</span> and Mars atmospheric trajectory options were examined under the constraints of an initial manned exploration scenario. Two chemically propelled vehicle options were considered: (1) an all propulsive configuration, and (2) a configuration which employs aerobraking at Earth and Mars with low lift/drag (L/D) shapes. Both the <span class="hlt">interplanetary</span> trajectory options as well as the Mars atmospheric passage are addressed to provide a coupled trajectory simulation. Direct and Venus swingby <span class="hlt">interplanetary</span> transfers with a 60 day Mars stopover are considered. The range and variation in both Earth and Mars entry velocity are also defined. Two promising mission strategies emerged from the study: (1) a 1.0 to 2.0 year Venus swingby mission, and (2) a 2.0 to 2.5 year direct mission. Through careful trajectory selection, 11 mission opportunities are identified in which the Mars entry velocity is between 6 and 10 km/sec and Earth entry velocity ranges from 11.5 to 12.5 km/sec. Simulation of the Earth return aerobraking maneuver is not performed. It is shown that a low L/D configuration is not feasible for Mars aerobraking without substantial improvements in the <span class="hlt">interplanetary</span> navigation system. However, even with an advanced navigation system, entry corridor and aerothermal requirements restrict the number of potential mission opportunities. It is also shown that for a large blunt Mars aerobrake configuration, the effects of radiative heating can be significant at entry velocities as low as 6.2 km/sec and will grow to dominate the aerothermal environment at entry velocities above 8.5 km/sec. Despite the additional system complexity associated with an aerobraking vehicle, the use of aerobraking was shown to significantly lower the required initial LEO weight. In</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002JGRA..107.1398H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002JGRA..107.1398H"><span>An evaluation of the statistical significance of the association between northward turnings of the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and substorm expansion onsets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hsu, Tung-Shin; McPherron, R. L.</p> <p>2002-11-01</p> <p>An outstanding problem in magnetospheric physics is deciding whether substorms are always triggered by external changes in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) or solar wind plasma, or whether they sometimes occur spontaneously. Over the past decade, arguments have been made on both sides of this issue. In fact, there is considerable evidence that some substorms are triggered. However, equally persuasive examples of substorms with no obvious trigger have been found. Because of conflicting views on this subject, further work is required to determine whether there is a physical relation between IMF triggers and substorm onset. In the work reported here a list of substorm onsets was created using two independent substorm signatures: sudden changes in the slope of the AL index and the start of a Pi 2 pulsation burst. Possible IMF triggers were determined from ISEE-2 observations. With the ISEE spacecraft near local noon immediately upstream of the bow shock, there can be little question about propagation delay to the magnetopause or whether a particular IMF feature hits the subsolar magnetopause. Thus it eliminates the objections that the calculated arrival time is subject to a large error or that the solar wind monitor missed a potential trigger incident at the subsolar point. Using a less familiar technique, statistics of point process, we find that the time delay between substorm onsets and the propagated arrival time of IMF triggers are clustered around zero. We estimate for independent processes that the probability of this clustering by chance alone is about 10-11. If we take into account the requirement that the IMF must have been southward prior to the onset, then the probability of clustering is higher, ˜10-5, but still extremely unlikely. Thus it is not possible to ascribe the apparent relation between IMF northward turnings and substorm onset to coincidence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22663343-polarized-line-formation-arbitrary-strength-magnetic-fields-angle-averaged-angle-dependent-partial-frequency-redistribution','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22663343-polarized-line-formation-arbitrary-strength-magnetic-fields-angle-averaged-angle-dependent-partial-frequency-redistribution"><span>Polarized Line Formation in Arbitrary Strength <span class="hlt">Magnetic</span> Fields Angle-<span class="hlt">averaged</span> and Angle-dependent Partial Frequency Redistribution</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Sampoorna, M.; Nagendra, K. N.; Stenflo, J. O., E-mail: sampoorna@iiap.res.in, E-mail: knn@iiap.res.in, E-mail: stenflo@astro.phys.ethz.ch</p> <p></p> <p><span class="hlt">Magnetic</span> fields in the solar atmosphere leave their fingerprints in the polarized spectrum of the Sun via the Hanle and Zeeman effects. While the Hanle and Zeeman effects dominate, respectively, in the weak and strong field regimes, both these effects jointly operate in the intermediate field strength regime. Therefore, it is necessary to solve the polarized line transfer equation, including the combined influence of Hanle and Zeeman effects. Furthermore, it is required to take into account the effects of partial frequency redistribution (PRD) in scattering when dealing with strong chromospheric lines with broad damping wings. In this paper, we presentmore » a numerical method to solve the problem of polarized PRD line formation in <span class="hlt">magnetic</span> fields of arbitrary strength and orientation. This numerical method is based on the concept of operator perturbation. For our studies, we consider a two-level atom model without hyperfine structure and lower-level polarization. We compare the PRD idealization of angle-<span class="hlt">averaged</span> Hanle–Zeeman redistribution matrices with the full treatment of angle-dependent PRD, to indicate when the idealized treatment is inadequate and what kind of polarization effects are specific to angle-dependent PRD. Because the angle-dependent treatment is presently computationally prohibitive when applied to realistic model atmospheres, we present the computed emergent Stokes profiles for a range of <span class="hlt">magnetic</span> fields, with the assumption of an isothermal one-dimensional medium.« less</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990GMS....58..385S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990GMS....58..385S"><span>Energetic ion and cosmic ray characteristics of a <span class="hlt">magnetic</span> cloud</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sanderson, T. R.; Beeck, J.; Marsden, R. G.; Tranquille, C.; Wenzel, K.-P.; McKibben, R. B.; Smith, E. J.</p> <p></p> <p>The large <span class="hlt">interplanetary</span> shock event of February 11, 1982, has yielded ISEE-3 energetic ion and <span class="hlt">magnetic</span> field data as well as ground-based neutron-monitor cosmic-ray data. The timing and the onset of the Forbush decrease associated with this shock event coincide with the arrival at the earth of its <span class="hlt">magnetic</span> cloud component; the duration of the decrease, similarly, corresponds to that of the cloud's passage past the earth. The large scattering mean free path readings suggest that while <span class="hlt">magnetic</span> cloud ions can easily travel along <span class="hlt">magnetic</span> field lines, they cannot travel across them, so that they cannot escape the cloud after entering it. Similarly, the cloud field lines prevented cosmic ray entrance, and could have prevented their reaching the earth. The cloud is therefore a major basis for the Forbush decrease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19840060501&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwhite%2Bcane','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19840060501&hterms=white+cane&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwhite%2Bcane"><span>Type II solar radio bursts, <span class="hlt">interplanetary</span> shocks, and energetic particle events</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cane, H. V.; Stone, R. G.</p> <p>1984-01-01</p> <p>Using the ISEE-3 radio astronomy experiment data 37 <span class="hlt">interplanetary</span> (IP) type II bursts have been identified in the period September 1978 to December 1981. These events and the associated phenomena are listed. The events are preceded by intense, soft X ray events with long decay times (LDEs) and type II and/or type IV bursts at meter wavelengths. The meter wavelength type II bursts are usually intense and exhibit herringbone structure. The extension of the herringbone structure into the kilometer wavelength range results in the occurrence of a shock accelerated (SA) event. The majority of the <span class="hlt">interplanetary</span> type II bursts are associated with energetic particle events. These results support other studies awhich indicate that energetic solar particles detected at 1 A.U. are generated by shock acceleration. From a preliminary analysis of the available data there appears to be a high correlation with white light coronal transients.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1402595-electron-dropout-echoes-induced-interplanetary-shock-van-allen-probes-observations','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1402595-electron-dropout-echoes-induced-interplanetary-shock-van-allen-probes-observations"><span>Electron dropout echoes induced by <span class="hlt">interplanetary</span> shock: Van Allen Probes observations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Hao, Y. X.; Zong, Q. -G.; Zhou, X. -Z.; ...</p> <p>2016-06-07</p> <p>On 23 November 2012, a sudden dropout of the relativistic electron flux was observed after an <span class="hlt">interplanetary</span> shock arrival. The dropout peaks at ~1 MeV and more than 80% of the electrons disappeared from the drift shell. Van Allen twin Probes observed a sharp electron flux dropout with clear energy dispersion signals. The repeating flux dropout and recovery signatures, or “dropout echoes”, constitute a new phenomenon referred to as a “drifting electron dropout” with a limited initial spatial range. The azimuthal range of the dropout is estimated to be on the duskside, from ~1300 to 0100 LT. We then concludemore » that the shock-induced electron dropout is not caused by the magnetopause shadowing. Furthermore, the dropout and consequent echoes suggest that the radial migration of relativistic electrons is induced by the strong dusk-dawn asymmetric <span class="hlt">interplanetary</span> shock compression on the magnetosphere.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160003117','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160003117"><span>Potential Cislunar and <span class="hlt">Interplanetary</span> Proving Ground Excursion Trajectory Concepts</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McGuire, Melissa L.; Strange, Nathan J.; Burke, Laura M.; MacDonald, Mark A.; McElrath, Timothy P.; Landau, Damon F.; Lantoine, Gregory; Hack, Kurt J.; Lopez, Pedro</p> <p>2016-01-01</p> <p>NASA has been investigating potential translunar excursion concepts to take place in the 2020s that would be used to test and demonstrate long duration life support and other systems needed for eventual Mars missions in the 2030s. These potential trajectory concepts could be conducted in the proving ground, a region of cislunar and near-Earth <span class="hlt">interplanetary</span> space where international space agencies could cooperate to develop the technologies needed for <span class="hlt">interplanetary</span> spaceflight. Enabled by high power Solar Electric Propulsion (SEP) technologies, the excursion trajectory concepts studied are grouped into three classes of increasing distance from the Earth and increasing technical difficulty: the first class of excursion trajectory concepts would represent a 90-120 day round trip trajectory with abort to Earth options throughout the entire length, the second class would be a 180-210 day round trip trajectory with periods in which aborts would not be available, and the third would be a 300-400 day round trip trajectory without aborts for most of the length of the trip. This paper provides a top-level summary of the trajectory and mission design of representative example missions of these three classes of excursion trajectory concepts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030022667','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030022667"><span><span class="hlt">Interplanetary</span> Coronal Mass Ejections in the Near-Earth Solar Wind During 1996-2002</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cane, H. V.; Richardson, I. G.</p> <p>2003-01-01</p> <p>We summarize the occurrence of <span class="hlt">interplanetary</span> coronal mass injections (ICMEs) in the near-Earth solar wind during 1996-2002, corresponding to the increasing and maximum phases of solar cycle 23. In particular, we give a detailed list of such events. This list, based on in-situ observations, is not confined to subsets of ICMEs, such as <span class="hlt">magnetic</span> clouds or those preceded by halo CMEs observed by the SOHO/LASCO coronagraph, and provides an overview of 214 ICMEs in the near-Earth solar wind during this period. The ICME rate increases by about an order of magnitude from solar minimum to solar maximum (when the rate is approximately 3 ICMEs/solar rotation period). The rate also shows a temporary reduction during 1999, and another brief, deeper reduction in late 2000-early 2001, which only approximately track variations in the solar 10 cm flux. In addition, there are occasional periods of several rotations duration when the ICME rate is enhanced in association with high solar activity levels. We find an indication of a periodic variation in the ICME rate, with a prominent period of approximately 165 days similar to that previously reported in various solar phenomena. It is found that the fraction of ICMEs that are <span class="hlt">magnetic</span> clouds has a solar cycle variation, the fraction being larger near solar minimum. For the subset of events that we could associate with a CME at the Sun, the transit speeds from the Sun to the Earth were highest after solar maximum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhDT.......119H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhDT.......119H"><span>Stormtime and <span class="hlt">Interplanetary</span> <span class="hlt">Magnetic</span> Field Drivers of Wave and Particle Acceleration Processes in the Magnetosphere-Ionosphere Transition Region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hatch, Spencer Mark</p> <p></p> <p>The magnetosphere-ionosphere (M-I) transition region is the several thousand-kilometer stretch between the cold, dense and variably resistive region of ionized atmospheric gases beginning tens of kilometers above the terrestrial surface, and the hot, tenuous, and conductive plasmas that interface with the solar wind at higher altitudes. The M-I transition region is therefore the site through which magnetospheric conditions, which are strongly susceptible to solar wind dynamics, are communicated to ionospheric plasmas, and vice versa. We systematically study the influence of geomagnetic storms on energy input, electron precipitation, and ion outflow in the M-I transition region, emphasizing the role of inertial Alfven waves both as a preferred mechanism for dynamic (instead of static) energy transfer and particle acceleration, and as a low-altitude manifestation of high-altitude interaction between the solar wind and the magnetosphere, as observed by the FAST satellite. Via superposed epoch analysis and high-latitude distributions derived as a function of storm phase, we show that storm main and recovery phase correspond to strong modulations of measures of Alfvenic activity in the vicinity of the cusp as well as premidnight. We demonstrate that storm main and recovery phases occur during 30% of the four-year period studied, but together account for more than 65% of global Alfvenic energy deposition and electron precipitation, and more than 70% of the coincident ion outflow. We compare observed <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) control of inertial Alfven wave activity with Lyon-Fedder-Mobarry global MHD simulations predicting that southward IMF conditions lead to generation of Alfvenic power in the magnetotail, and that duskward IMF conditions lead to enhanced prenoon Alfvenic power in the Northern Hemisphere. Observed and predicted prenoon Alfvenic power enhancements contrast with direct-entry precipitation, which is instead enhanced postnoon. This situation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUSMSH51B..02F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUSMSH51B..02F"><span>Operational, Real-Time, Sun-to-Earth <span class="hlt">Interplanetary</span> Shock Predictions During Solar Cycle 23</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fry, C. D.; Dryer, M.; Sun, W.; Deehr, C. S.; Smith, Z.; Akasofu, S.</p> <p>2002-05-01</p> <p>We report on our progress in predicting <span class="hlt">interplanetary</span> shock arrival time (SAT) in real-time, using three forecast models: the Hakamada-Akasofu-Fry (HAF) modified kinematic model, the <span class="hlt">Interplanetary</span> Shock Propagation Model (ISPM) and the Shock Time of Arrival (STOA) model. These models are run concurrently to provide real-time predictions of the arrival time at Earth of <span class="hlt">interplanetary</span> shocks caused by solar events. These "fearless forecasts" are the first, and presently only, publicly distributed predictions of SAT and are undergoing quantitative evaluation for operational utility and scientific benchmarking. All three models predict SAT, but the HAF model also provides a global view of the propagation of <span class="hlt">interplanetary</span> shocks through the pre-existing, non-uniform heliospheric structure. This allows the forecaster to track the propagation of the shock and to differentiate between shocks caused by solar events and those associated with co-rotating interaction regions (CIRs). This study includes 173 events during the period February, 1997 to October, 2000. Shock predictions were compared with spacecraft observations at the L1 location to determine how well the models perform. Sixty-eight shocks were observed at L1 within 120 hours of an event. We concluded that 6 of these observed shocks were caused by CIRs, and the remainder were caused by solar events. The forecast skill of the models are presented in terms of RMS errors, contingency tables and skill scores commonly used by the weather forecasting community. The false alarm rate for HAF was higher than for ISPM or STOA but much lower than for predictions based upon empirical studies or climatology. Of the parameters used to characterize a shock source at the Sun, the initial speed of the coronal shock, as represented by the observed metric type II speed, has the largest influence on the predicted SAT. We also found that HAF model predictions based upon type II speed are generally better for shocks originating from</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160008249&hterms=earth+system+modeling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dearth%2Bsystem%2Bmodeling','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160008249&hterms=earth+system+modeling&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dearth%2Bsystem%2Bmodeling"><span>Small Spacecraft System-Level Design and Optimization for <span class="hlt">Interplanetary</span> Trajectories</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Spangelo, Sara; Dalle, Derek; Longmier, Ben</p> <p>2014-01-01</p> <p>The feasibility of an <span class="hlt">interplanetary</span> mission for a CubeSat, a type of miniaturized spacecraft, that uses an emerging technology, the CubeSat Ambipolar Thruster (CAT) is investigated. CAT is a large delta-V propulsion system that uses a high-density plasma source that has been miniaturized for small spacecraft applications. An initial feasibility assessment that demonstrated escaping Low Earth Orbit (LEO) and achieving Earth-escape trajectories with a 3U CubeSat and this thruster technology was demonstrated in previous work. We examine a mission architecture with a trajectory that begins in Earth orbits such as LEO and Geostationary Earth Orbit (GEO) which escapes Earth orbit and travels to Mars, Jupiter, or Saturn. The goal was to minimize travel time to reach the destinations and considering trade-offs between spacecraft dry mass, fuel mass, and solar power array size. Sensitivities to spacecraft dry mass and available power are considered. CubeSats are extremely size, mass, and power constrained, and their subsystems are tightly coupled, limiting their performance potential. System-level modeling, simulation, and optimization approaches are necessary to find feasible and optimal operational solutions to ensure system-level interactions are modeled. Thus, propulsion, power/energy, attitude, and orbit transfer models are integrated to enable systems-level analysis and trades. The CAT technology broadens the possible missions achievable with small satellites. In particular, this technology enables more sophisticated maneuvers by small spacecraft such as polar orbit insertion from an equatorial orbit, LEO to GEO transfers, Earth-escape trajectories, and transfers to other <span class="hlt">interplanetary</span> bodies. This work lays the groundwork for upcoming CubeSat launch opportunities and supports future development of <span class="hlt">interplanetary</span> and constellation CubeSat and small satellite mission concepts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMSH51A2441T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMSH51A2441T"><span>Diffuse <span class="hlt">Interplanetary</span> Radio Emission (DIRE) Accompanying Type II Radio Bursts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Teklu, T. B.; Gopalswamy, N.; Makela, P. A.; Yashiro, S.; Akiyama, S.; Xie, H.</p> <p>2015-12-01</p> <p>We report on an unusual drifting feature in the radio dynamic spectra at frequencies below 14 MHz observed by the Radio and Plasma Wave (WAVES) experiment on board the Wind spacecraft. We call this feature as "Diffuse <span class="hlt">Interplanetary</span> Radio Emission (DIRE)". The DIRE events are generally associated with intense <span class="hlt">interplanetary</span> type II radio bursts produced by shocks driven by coronal mass ejections (CMEs). DIREs drift like type II bursts in the dynamic spectra, but the drifting feature consist of a series of short-duration spikes (similar to a type I chain). DIREs occur at higher frequencies than the associated type II bursts, with no harmonic relationship with the type II burst. The onset of DIREs is delayed by several hours from the onset of the eruption. Comparing the radio dynamic spectra with white-light observations from the Solar and Heliospheric Observatory (SOHO) mission, we find that the CMEs are generally very energetic (fast and mostly halos). We suggest that the DIRE source is typically located at the flanks of the CME-driven shock that is still at lower heliocentric distances.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22521487-density-fluctuations-upstream-downstream-interplanetary-shocks','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22521487-density-fluctuations-upstream-downstream-interplanetary-shocks"><span>DENSITY FLUCTUATIONS UPSTREAM AND DOWNSTREAM OF <span class="hlt">INTERPLANETARY</span> SHOCKS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Pitňa, A.; Šafránková, J.; Němeček, Z.</p> <p>2016-03-01</p> <p><span class="hlt">Interplanetary</span> (IP) shocks as typical large-scale disturbances arising from processes such as stream–stream interactions or <span class="hlt">Interplanetary</span> Coronal Mass Ejection (ICME) launching play a significant role in the energy redistribution, dissipation, particle heating, acceleration, etc. They can change the properties of the turbulent cascade on shorter scales. We focus on changes of the level and spectral properties of ion flux fluctuations upstream and downstream of fast forward oblique shocks. Although the fluctuation level increases by an order of magnitude across the shock, the spectral slope in the magnetohydrodynamic range is conserved. The frequency spectra upstream of IP shocks are the same as those inmore » the solar wind (if not spoiled by foreshock waves). The spectral slopes downstream are roughly proportional to the corresponding slopes upstream, suggesting that the properties of the turbulent cascade are conserved across the shock; thus, the shock does not destroy the shape of the spectrum as turbulence passes through it. Frequency spectra downstream of IP shocks often exhibit “an exponential decay” in the ion kinetic range that was earlier reported at electron scales in the solar wind or at ion scales in the interstellar medium. We suggest that the exponential shape of ion flux spectra in this range is caused by stronger damping of the fluctuations in the downstream region.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19830042535&hterms=Wave+Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DWave%2BEnergy','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19830042535&hterms=Wave+Energy&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DWave%2BEnergy"><span>Acceleration of low-energy protons and alpha particles at <span class="hlt">interplanetary</span> shock waves</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scholer, M.; Hovestadt, D.; Ipavich, F. M.; Gloeckler, G.</p> <p>1983-01-01</p> <p>The low-energy protons and alpha particles in the energy range 30 keV/charge to 150 keV/charge associated with three different <span class="hlt">interplanetary</span> shock waves in the immediate preshock and postshock region are studied using data obtained by the ISEE 3. The spatial distributions in the preshock and postshock medium are presented, and the dependence of the phase space density at different energies on the distance from the shock and on the form of the distribution function of both species immediately at the shock is examined. It is found that in the preshock region the particles are flowing in the solar wind frame of reference away from the shock and in the postshock medium the distribution is more or less isotropic in this frame of reference. The distribution function in the postshock region can be represented by a power law in energy which has the same spectral exponent for both protons and alpha particles. It is concluded that the first-order Fermi acceleration process can consistently explain the data, although the spectra of diffuse bow shock associated particles are different from the spectra of the <span class="hlt">interplanetary</span> shock-associated particles in the immediate vicinity of the shock. In addition, the mean free path of the low energy ions in the preshock medium is found to be considerably smaller than the mean free path determined by the turbulence of the background <span class="hlt">interplanetary</span> medium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810044425&hterms=radiation+Solar&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dradiation%2BSolar','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810044425&hterms=radiation+Solar&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dradiation%2BSolar"><span>Polar solar wind and interstellar wind properties from <span class="hlt">interplanetary</span> Lyman-alpha radiation measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Witt, N.; Blum, P. W.; Ajello, J. M.</p> <p>1981-01-01</p> <p>The analysis of Mariner 10 observations of Lyman-alpha resonance radiation shows an increase of <span class="hlt">interplanetary</span> neutral hydrogen densities above the solar poles. This increase is caused by a latitudinal variation of the solar wind velocity and/or flux. Using both the Mariner 10 results and other solar wind observations, the values of the solar wind flux and velocity with latitude are determined for several cases of interest. The latitudinal variation of <span class="hlt">interplanetary</span> hydrogen gas, arising from the solar wind latitudinal variation, is shown to be most pronounced in the inner solar system. From this result it is shown that spacecraft Lyman-alpha observations are more sensitive to the latitudinal anisotropy for a spacecraft location in the inner solar system near the downwind axis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SoPh..284...77K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SoPh..284...77K"><span>Propagation Characteristics of CMEs Associated with <span class="hlt">Magnetic</span> Clouds and Ejecta</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kim, R.-S.; Gopalswamy, N.; Cho, K.-S.; Moon, Y.-J.; Yashiro, S.</p> <p>2013-05-01</p> <p>We have investigated the characteristics of <span class="hlt">magnetic</span> cloud (MC) and ejecta (EJ) associated coronal mass ejections (CMEs) based on the assumption that all CMEs have a flux rope structure. For this, we used 54 CMEs and their <span class="hlt">interplanetary</span> counterparts (<span class="hlt">interplanetary</span> CMEs: ICMEs) that constitute the list of events used by the NASA/LWS Coordinated Data Analysis Workshop (CDAW) on CME flux ropes. We considered the location, angular width, and speed as well as the direction parameter, D. The direction parameter quantifies the degree of asymmetry of the CME shape in coronagraph images, and shows how closely the CME propagation is directed to Earth. For the 54 CDAW events, we found the following properties of the CMEs: i) the <span class="hlt">average</span> value of D for the 23 MCs (0.62) is larger than that for the 31 EJs (0.49), which indicates that the MC-associated CMEs propagate more directly toward the Earth than the EJ-associated CMEs; ii) comparison between the direction parameter and the source location shows that the majority of the MC-associated CMEs are ejected along the radial direction, while many of the EJ-associated CMEs are ejected non-radially; iii) the mean speed of MC-associated CMEs (946 km s-1) is faster than that of EJ-associated CMEs (771 km s-1). For seven very fast CMEs (≥ 1500 km s-1), all CMEs with large D (≥ 0.4) are associated with MCs and the CMEs with small D are associated with EJs. From the statistical analysis of CME parameters, we found the superiority of the direction parameter. Based on these results, we suggest that the CME trajectory essentially determines the observed ICME structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930005579','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930005579"><span><span class="hlt">Interplanetary</span> program to optimize simulated trajectories (IPOST). Volume 4: Sample cases</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hong, P. E.; Kent, P. D; Olson, D. W.; Vallado, C. A.</p> <p>1992-01-01</p> <p>The <span class="hlt">Interplanetary</span> Program to Optimize Simulated Trajectories (IPOST) is intended to support many analysis phases, from early <span class="hlt">interplanetary</span> feasibility studies through spacecraft development and operations. The IPOST output provides information for sizing and understanding mission impacts related to propulsion, guidance, communications, sensor/actuators, payload, and other dynamic and geometric environments. IPOST models three degree of freedom trajectory events, such as launch/ascent, orbital coast, propulsive maneuvering (impulsive and finite burn), gravity assist, and atmospheric entry. Trajectory propagation is performed using a choice of Cowell, Encke, Multiconic, Onestep, or Conic methods. The user identifies a desired sequence of trajectory events, and selects which parameters are independent (controls) and dependent (targets), as well as other constraints and the cost function. Targeting and optimization are performed using the Standard NPSOL algorithm. The IPOST structure allows sub-problems within a master optimization problem to aid in the general constrained parameter optimization solution. An alternate optimization method uses implicit simulation and collocation techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19930010932','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19930010932"><span><span class="hlt">Interplanetary</span> Program to Optimize Simulated Trajectories (IPOST). Volume 2: Analytic manual</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hong, P. E.; Kent, P. D.; Olson, D. W.; Vallado, C. A.</p> <p>1992-01-01</p> <p>The <span class="hlt">Interplanetary</span> Program to Optimize Space Trajectories (IPOST) is intended to support many analysis phases, from early <span class="hlt">interplanetary</span> feasibility studies through spacecraft development and operations. The IPOST output provides information for sizing and understanding mission impacts related to propulsion, guidance, communications, sensor/actuators, payload, and other dynamic and geometric environments. IPOST models three degree of freedom trajectory events, such as launch/ascent, orbital coast, propulsive maneuvering (impulsive and finite burn), gravity assist, and atmospheric entry. Trajectory propagation is performed using a choice of Cowell, Encke, Multiconic, Onestep, or Conic methods. The user identifies a desired sequence of trajectory events, and selects which parameters are independent (controls) and dependent (targets), as well as other constraints and the cost function. Targeting and optimization is performed using the Stanford NPSOL algorithm. IPOST structure allows subproblems within a master optimization problem to aid in the general constrained parameter optimization solution. An alternate optimization method uses implicit simulation and collocation techniques.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19770019111','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19770019111"><span>The mean <span class="hlt">magnetic</span> field of the sun: Observations at Stanford</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Scherrer, P. H.; Wilcox, J. M.; Svalgaard, L.; Duvall, T. L., Jr.; Dittmer, P. H.; Gustafson, E. K.</p> <p>1977-01-01</p> <p>A solar telescope was built at Stanford University to study the organization and evolution of large-scale solar <span class="hlt">magnetic</span> fields and velocities. The observations are made using a Babcock-type magnetograph which is connected to a 22.9 m vertical Littrow spectrograph. Sun-as-a-star integrated light measurements of the mean solar <span class="hlt">magnetic</span> field were made daily since May 1975. The typical mean field magnitude is about 0.15 gauss with typical measurement error less than 0.05 gauss. The mean field polarity pattern is essentially identical to the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field sector structure (seen near the earth with a 4 day lag). The differences in the observed structures can be understood in terms of a warped current sheet model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820021375','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820021375"><span>Pioneer 10/11 data analysis of the <span class="hlt">magnetic</span> field experiment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Jones, D. E.</p> <p>1982-01-01</p> <p>Work conducted in support of the Pioneer missions to Jupiter (10,11), and Saturn (11) as well as the reduction, analysis and interpretation of <span class="hlt">magnetic</span> field data obtained by the vector helium magnetometer on the Pioneer 10 and 11 spacecraft is summarized. Initial efforts concentrated primarily on the <span class="hlt">interplanetary</span> data, and those aspcts of the data of relevance to obtaining a better understanding of the interaction of the <span class="hlt">magnetized</span> solar wind with the terrestrial <span class="hlt">magnetic</span> field. After encounters of Jupiter and Saturn, the emphasis of research was directed primarily to an analysis of the planetary data. In particular, it soon became clear that there was a need for modelling of the various candidate magnetospheric currents suggested by the data. Results not published as yet, are also summarized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015A%26A...583A.127N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015A%26A...583A.127N"><span>North-south asymmetry in the <span class="hlt">magnetic</span> deflection of polar coronal hole jets</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nisticò, G.; Zimbardo, G.; Patsourakos, S.; Bothmer, V.; Nakariakov, V. M.</p> <p>2015-11-01</p> <p>Context. Measurements of the sunspots area, of the <span class="hlt">magnetic</span> field in the <span class="hlt">interplanetary</span> medium, and of the heliospheric current sheet (HCS) position, reveal a possible north-south (N-S) asymmetry in the <span class="hlt">magnetic</span> field of the Sun. This asymmetry could cause the bending of the HCS of the order of 5-10 deg in the southward direction, and it appears to be a recurrent characteristic of the Sun during the minima of solar activity. Aims: We study the N-S asymmetry as inferred from measurements of the deflection of polar coronal hole jets when they propagate throughout the corona. Methods: Since the corona is an environment where the <span class="hlt">magnetic</span> pressure is greater than the kinetic pressure (β ≪ 1), we can assume that the <span class="hlt">magnetic</span> field controls the dynamics of plasma. On <span class="hlt">average</span>, jets follow <span class="hlt">magnetic</span> field lines during their propagation, highlighting their local direction. We measured the position angles at 1 R⊙ and at 2 R⊙ of 79 jets, based on the Solar TErrestrial RElations Observatory (STEREO) ultraviolet and white-light coronagraph observations during the solar minimum period March 2007-April 2008. The <span class="hlt">average</span> jet deflection is studied both in the plane perpendicular to the line of sight and, for a reduced number of jets, in 3D space. The observed jet deflection is studied in terms of an axisymmetric <span class="hlt">magnetic</span> field model comprising dipole (g1), quadrupole (g2), and esapole (g3) moments. Results: We found that the propagation of the jets is not radial, which is in agreement with the deflection due to <span class="hlt">magnetic</span> field lines. Moreover, the amount of the deflection is different between jets over the north and those from the south pole. A comparison of jet deflections and field line tracing shows that a ratio g2/g1 ≃ -0.5 for the quadrupole and a ratio g3/g1 ≃ 1.6-2.0 for the esapole can describe the field. The presence of a non-negligible quadrupole moment confirms the N-S asymmetry of the solar <span class="hlt">magnetic</span> field for the considered period. Conclusions: We find that the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150007929','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150007929"><span><span class="hlt">Interplanetary</span> and Interstellar Dust Observed by the Wind/WAVES Electric Field Instrument</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Malaspina, David; Horanyi, M.; Zaslavsky, A.; Goetz, K.; Wilson, L. B., III; Kersten, K.</p> <p>2014-01-01</p> <p>Observations of hypervelocity dust particles impacting the Wind spacecraft are reported here for the first time using data from the WindWAVES electric field instrument. A unique combination of rotating spacecraft, amplitude-triggered high-cadence waveform collection, and electric field antenna configuration allow the first direct determination of dust impact direction by any spacecraft using electric field data. Dust flux and impact direction data indicate that the observed dust is approximately micron-sized with both <span class="hlt">interplanetary</span> and interstellar populations. Nanometer radius dust is not detected by Wind during times when nanometer dust is observed on the STEREO spacecraft and both spacecraft are in close proximity. Determined impact directions suggest that <span class="hlt">interplanetary</span> dust detected by electric field instruments at 1 AU is dominated by particles on bound trajectories crossing Earths orbit, rather than dust with hyperbolic orbits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140006922','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140006922"><span>The Radiation, <span class="hlt">Interplanetary</span> Shocks, and Coronal Sources (RISCS) Toolset</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Zank, G. P.; Spann, J.</p> <p>2014-01-01</p> <p>We outline a plan to develop a physics based predictive toolset RISCS to describe the <span class="hlt">interplanetary</span> energetic particle and radiation environment throughout the inner heliosphere, including at the Earth. To forecast and "nowcast" the radiation environment requires the fusing of three components: 1) the ability to provide probabilities for incipient solar activity; 2) the use of these probabilities and daily coronal and solar wind observations to model the 3D spatial and temporal heliosphere, including <span class="hlt">magnetic</span> field structure and transients, within 10 AU; and 3) the ability to model the acceleration and transport of energetic particles based on current and anticipated coronal and heliospheric conditions. We describe how to address 1) - 3) based on our existing, well developed, and validated codes and models. The goal of RISCS toolset is to provide an operational forecast and "nowcast" capability that will a) predict solar energetic particle (SEP) intensities; b) spectra for protons and heavy ions; c) predict maximum energies and their duration; d) SEP composition; e) cosmic ray intensities, and f) plasma parameters, including shock arrival times, strength and obliquity at any given heliospheric location and time. The toolset would have a 72 hour predicative capability, with associated probabilistic bounds, that would be updated hourly thereafter to improve the predicted event(s) and reduce the associated probability bounds. The RISCS toolset would be highly adaptable and portable, capable of running on a variety of platforms to accommodate various operational needs and requirements.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20040047163&hterms=SPIRAL+MODEL&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DSPIRAL%2BMODEL','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20040047163&hterms=SPIRAL+MODEL&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DSPIRAL%2BMODEL"><span>Semiempirical Two-Dimensional Magnetohydrodynamic Model of the Solar Corona and <span class="hlt">Interplanetary</span> Medium</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Sittler, Edward C., Jr.; Guhathakurta, Madhulika</p> <p>1999-01-01</p> <p>We have developed a two-dimensional semiempirical MHD model of the solar corona and solar wind. The model uses empirically derived electron density profiles from white-light coronagraph data measured during the Skylub period and an empirically derived model of the <span class="hlt">magnetic</span> field which is fitted to observed streamer topologies, which also come from the white-light coronagraph data The electron density model comes from that developed by Guhathakurta and coworkers. The electron density model is extended into <span class="hlt">interplanetary</span> space by using electron densities derived from the Ulysses plasma instrument. The model also requires an estimate of the solar wind velocity as a function of heliographic latitude and radial component of the <span class="hlt">magnetic</span> field at 1 AU, both of which can be provided by the Ulysses spacecraft. The model makes estimates as a function of radial distance and latitude of various fluid parameters of the plasma such as flow velocity V, effective temperature T(sub eff), and effective heat flux q(sub eff), which are derived from the equations of conservation of mass, momentum, and energy, respectively. The term effective indicates that wave contributions could be present. The model naturally provides the spiral pattern of the <span class="hlt">magnetic</span> field far from the Sun and an estimate of the large-scale surface <span class="hlt">magnetic</span> field at the Sun, which we estimate to be approx. 12 - 15 G. The <span class="hlt">magnetic</span> field model shows that the large-scale surface <span class="hlt">magnetic</span> field is dominated by an octupole term. The model is a steady state calculation which makes the assumption of azimuthal symmetry and solves the various conservation equations in the rotating frame of the Sun. The conservation equations are integrated along the <span class="hlt">magnetic</span> field direction in the rotating frame of the Sun, thus providing a nearly self-consistent calculation of the fluid parameters. The model makes a minimum number of assumptions about the physics of the solar corona and solar wind and should provide a very accurate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750020523','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750020523"><span>The source of the electric field in the nightside magnetosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stern, D. P.</p> <p>1975-01-01</p> <p>In the open magnetosphere model <span class="hlt">magnetic</span> field lines from the polar caps connect to the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field and conduct an electric field from <span class="hlt">interplanetary</span> space to the polar ionosphere. By examining the <span class="hlt">magnetic</span> flux involved it is concluded that only slightly more than half of the <span class="hlt">magnetic</span> flux in the polar caps belongs to open field lines and that such field lines enter or leave the magnetosphere through narrow elongated windows stretching the tail. These window regions are identified with the tail's boundary region and shift their position with changes in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field, in particular when a change of <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> sector occurs. The circuit providing electric current in the magnetopause and the plasma sheet is extended across those windows; thus energy is drained from the <span class="hlt">interplanetary</span> electric field and an electric potential drop is produced across the plasma sheet. The polar cap receives its electric field from <span class="hlt">interplanetary</span> space on the day side from open <span class="hlt">magnetic</span> field lines and on the night side from closed field lines leading to the plasma sheet. The theory described provides improved understanding of <span class="hlt">magnetic</span> flux bookkeeping, of the origin of Birkeland currents, and of the boundary layer of the geomagnetic tail.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19750032539&hterms=luck&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dluck','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19750032539&hterms=luck&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dluck"><span>The long life of Pioneer <span class="hlt">interplanetary</span> spacecraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dixon, W. J.</p> <p>1974-01-01</p> <p>The Pioneer 6 to 9 <span class="hlt">interplanetary</span> spacecraft were launched in 1965, 66, 67, and 68. All continue to operate in various orbits about the sun, gathering data on the solar system environment. Pioneer 10 was launched in 1972, and is now more than halfway to Jupiter, with all systems performing their required functions. The paper reviews these programs and the few anomalies which have been observed. The long-term mission success is discussed in terms of possible causative factors: simplicity in design and operation, redundancy in function and in equipment, comprehensive development and acceptance tests, the mildness of the space environment, and luck.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH21A2650J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH21A2650J"><span>An Iterative <span class="hlt">Interplanetary</span> Scintillation (IPS) Analysis Using Time-dependent 3-D MHD Models as Kernels</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jackson, B. V.; Yu, H. S.; Hick, P. P.; Buffington, A.; Odstrcil, D.; Kim, T. K.; Pogorelov, N. V.; Tokumaru, M.; Bisi, M. M.; Kim, J.; Yun, J.</p> <p>2017-12-01</p> <p>The University of California, San Diego has developed an iterative remote-sensing time-dependent three-dimensional (3-D) reconstruction technique which provides volumetric maps of density, velocity, and <span class="hlt">magnetic</span> field. We have applied this technique in near real time for over 15 years with a kinematic model approximation to fit data from ground-based <span class="hlt">interplanetary</span> scintillation (IPS) observations. Our modeling concept extends volumetric data from an inner boundary placed above the Alfvén surface out to the inner heliosphere. We now use this technique to drive 3-D MHD models at their inner boundary and generate output 3-D data files that are fit to remotely-sensed observations (in this case IPS observations), and iterated. These analyses are also iteratively fit to in-situ spacecraft measurements near Earth. To facilitate this process, we have developed a traceback from input 3-D MHD volumes to yield an updated boundary in density, temperature, and velocity, which also includes <span class="hlt">magnetic</span>-field components. Here we will show examples of this analysis using the ENLIL 3D-MHD and the University of Alabama Multi-Scale Fluid-Kinetic Simulation Suite (MS-FLUKSS) heliospheric codes. These examples help refine poorly-known 3-D MHD variables (i.e., density, temperature), and parameters (gamma) by fitting heliospheric remotely-sensed data between the region near the solar surface and in-situ measurements near Earth.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810054119&hterms=electron+microscope&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Delectron%2Bmicroscope','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810054119&hterms=electron+microscope&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Delectron%2Bmicroscope"><span><span class="hlt">Interplanetary</span> dust in the transmission electron microscope - Diverse materials from the early solar system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fraundorf, P.</p> <p>1981-01-01</p> <p>An analytical electron microscope study of dispersed <span class="hlt">interplanetary</span> dust aggregates collected in the earth's stratosphere shows that, in spite of their similarities, the aggregates exhibit significant differences in composition, internal morphology, and mineralogy. Of 11 chondritic particles examined, two consist mostly of a noncrystalline chondritic material with an atomic S/Fe ratio equal to or greater than 2 in places, one consists of submicron metal and reduced silicate 'microchondrules' and sulfide grains embedded in a carbonaceous matrix, and another consists of submicron <span class="hlt">magnetic</span>-decorated unequilibrated silicate and sulfide grains with thick low-Z coatings. Although the particles are unmetamorphosed by criteria commonly applied for chondritic meteorites, the presence of reduced chemistries and the ubiquity of mafic, instead of hydrated, silicates confirm that they are not simply C1 or C2 chondrite matrix material. The observations indicate that portions of some particles have not been significantly altered by thermal or radiation processes since their assembly, and that the particles probably contain fine debris from diverse processes in the early solar system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24642508','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24642508"><span>Observations of an extreme storm in <span class="hlt">interplanetary</span> space caused by successive coronal mass ejections.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liu, Ying D; Luhmann, Janet G; Kajdič, Primož; Kilpua, Emilia K J; Lugaz, Noé; Nitta, Nariaki V; Möstl, Christian; Lavraud, Benoit; Bale, Stuart D; Farrugia, Charles J; Galvin, Antoinette B</p> <p>2014-03-18</p> <p>Space weather refers to dynamic conditions on the Sun and in the space environment of the Earth, which are often driven by solar eruptions and their subsequent <span class="hlt">interplanetary</span> disturbances. It has been unclear how an extreme space weather storm forms and how severe it can be. Here we report and investigate an extreme event with multi-point remote-sensing and in situ observations. The formation of the extreme storm showed striking novel features. We suggest that the in-transit interaction between two closely launched coronal mass ejections resulted in the extreme enhancement of the ejecta <span class="hlt">magnetic</span> field observed near 1 AU at STEREO A. The fast transit to STEREO A (in only 18.6 h), or the unusually weak deceleration of the event, was caused by the preconditioning of the upstream solar wind by an earlier solar eruption. These results provide a new view crucial to solar physics and space weather as to how an extreme space weather event can arise from a combination of solar eruptions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMSH53A2551G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMSH53A2551G"><span><span class="hlt">Magnetic</span> storm generation by large-scale complex structure Sheath/ICME</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grigorenko, E. E.; Yermolaev, Y. I.; Lodkina, I. G.; Yermolaev, M. Y.; Riazantseva, M.; Borodkova, N. L.</p> <p>2017-12-01</p> <p>We study temporal profiles of <span class="hlt">interplanetary</span> plasma and <span class="hlt">magnetic</span> field parameters as well as magnetospheric indices. We use our catalog of large-scale solar wind phenomena for 1976-2000 interval (see the catalog for 1976-2016 in web-side ftp://ftp.iki.rssi.ru/pub/omni/ prepared on basis of OMNI database (Yermolaev et al., 2009)) and the double superposed epoch analysis method (Yermolaev et al., 2010). Our analysis showed (Yermolaev et al., 2015) that <span class="hlt">average</span> profiles of Dst and Dst* indices decrease in Sheath interval (<span class="hlt">magnetic</span> storm activity increases) and increase in ICME interval. This profile coincides with inverted distribution of storm numbers in both intervals (Yermolaev et al., 2017). This behavior is explained by following reasons. (1) IMF magnitude in Sheath is higher than in Ejecta and closed to value in MC. (2) Sheath has 1.5 higher efficiency of storm generation than ICME (Nikolaeva et al., 2015). The most part of so-called CME-induced storms are really Sheath-induced storms and this fact should be taken into account during Space Weather prediction. The work was in part supported by the Russian Science Foundation, grant 16-12-10062. References. 1. Nikolaeva N.S., Y. I. Yermolaev and I. G. Lodkina (2015), Modeling of the corrected Dst* index temporal profile on the main phase of the <span class="hlt">magnetic</span> storms generated by different types of solar wind, Cosmic Res., 53(2), 119-127 2. Yermolaev Yu. I., N. S. Nikolaeva, I. G. Lodkina and M. Yu. Yermolaev (2009), Catalog of Large-Scale Solar Wind Phenomena during 1976-2000, Cosmic Res., , 47(2), 81-94 3. Yermolaev, Y. I., N. S. Nikolaeva, I. G. Lodkina, and M. Y. Yermolaev (2010), Specific <span class="hlt">interplanetary</span> conditions for CIR-induced, Sheath-induced, and ICME-induced geomagnetic storms obtained by double superposed epoch analysis, Ann. Geophys., 28, 2177-2186 4. Yermolaev Yu. I., I. G. Lodkina, N. S. Nikolaeva and M. Yu. Yermolaev (2015), Dynamics of large-scale solar wind streams obtained by the double superposed epoch</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PEPI..276...93T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PEPI..276...93T"><span>A time-<span class="hlt">averaged</span> regional model of the Hermean <span class="hlt">magnetic</span> field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thébault, E.; Langlais, B.; Oliveira, J. S.; Amit, H.; Leclercq, L.</p> <p>2018-03-01</p> <p>This paper presents the first regional model of the <span class="hlt">magnetic</span> field of Mercury developed with mathematical continuous functions. The model has a horizontal spatial resolution of about 830 km at the surface of the planet, and it is derived without any a priori information about the geometry of the internal and external fields or regularization. It relies on an extensive dataset of the MESSENGER's measurements selected over its entire orbital lifetime between 2011 and 2015. A first order separation between the internal and the external fields over the Northern hemisphere is achieved under the assumption that the <span class="hlt">magnetic</span> field measurements are acquired in a source free region within the magnetospheric cavity. When downward continued to the core-mantle boundary, the model confirms some of the general structures observed in previous studies such as the dominance of zonal field, the location of the North <span class="hlt">magnetic</span> pole, and the global absence of significant small scale structures. The transformation of the regional model into a global spherical harmonic one provides an estimate for the axial quadrupole to axial dipole ratio of about g20/g10 = 0.27 . This is much lower than previous estimates of about 0.40. We note that it is possible to obtain a similar ratio provided that more weight is put on the location of the <span class="hlt">magnetic</span> equator and less elsewhere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016cosp...41E1914T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016cosp...41E1914T"><span>Heliospheric Impact on Cosmic Rays Modulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tiwari, Bhupendra Kumar</p> <p>2016-07-01</p> <p>Heliospheric Impact on Cosmic RaysModulation B. K. Tiwari Department of Physics, A. P. S. University, Rewa (M.P.), btiwari70@yahoo.com Cosmic rays (CRs) flux at earth is modulated by the heliosphereric <span class="hlt">magnetic</span> field and the structure of the heliosphere, controls by solar outputs and their variability. Sunspots numbers (SSN) is often treated as a primary indicator of solar activity (SA). GCRs entering the helioshphere are affected by the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) and solar wind speed, their modulation varies with the varying solar activity. The observation based on data recoded from Omniweb data Centre for solar- <span class="hlt">interplanetary</span> activity indices and monthly mean count rate of cosmic ray intensity (CRI) data from neutron monitors of different cut-off rigidities(Rc) (Moscow Rc=2.42Gv and Oulu Rc=0.80Gv). During minimum solar activity periodof solar cycle 23/24, the sun is remarkably quiet, weakest strength of the IMF and least dense and slowest, solar wind speed, whereas, in 2003, highest value of yearly <span class="hlt">averaged</span> solar wind speed (~568 Km/sec) associated with several coronal holes, which generate high speed wind stream has been recorded. It is observed that GCRs fluxes reduces and is high anti-correlated with SSN (0.80) and IMF (0.86). CRI modulation produces by a strong solar flare, however, CME associated solar flare produce more disturbance in the <span class="hlt">interplanetary</span> medium as well as in geomagnetic field. It is found that count rate of cosmic ray intensity and solar- <span class="hlt">interplanetary</span> parameters were inverse correlated and solar indices were positive correlated. Keywords- Galactic Cosmic rays (GCRs), Sunspot number (SSN), Solar activity (SA), Coronal Mass Ejection (CME), <span class="hlt">Interplanetary</span> <span class="hlt">magnetic</span> field (IMF)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110012255','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110012255"><span>CFDP for <span class="hlt">Interplanetary</span> Overlay Network</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Burleigh, Scott C.</p> <p>2011-01-01</p> <p>The CCSDS (Consultative Committee for Space Data Systems) File Delivery Protocol for <span class="hlt">Interplanetary</span> Overlay Network (CFDP-ION) is an implementation of CFDP that uses IO' s DTN (delay tolerant networking) implementation as its UT (unit-data transfer) layer. Because the DTN protocols effect automatic, reliable transmission via multiple relays, CFDP-ION need only satisfy the requirements for Class 1 ("unacknowledged") CFDP. This keeps the implementation small, but without loss of capability. This innovation minimizes processing resources by using zero-copy objects for file data transmission. It runs without modification in VxWorks, Linux, Solaris, and OS/X. As such, this innovation can be used without modification in both flight and ground systems. Integration with DTN enables the CFDP implementation itself to be very simple; therefore, very small. Use of ION infrastructure minimizes consumption of storage and processing resources while maximizing safety.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22522322-solar-interacting-protons-versus-interplanetary-protons-core-plus-halo-model-diffusive-shock-acceleration-stochastic-re-acceleration','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22522322-solar-interacting-protons-versus-interplanetary-protons-core-plus-halo-model-diffusive-shock-acceleration-stochastic-re-acceleration"><span>SOLAR INTERACTING PROTONS VERSUS <span class="hlt">INTERPLANETARY</span> PROTONS IN THE CORE PLUS HALO MODEL OF DIFFUSIVE SHOCK ACCELERATION AND STOCHASTIC RE-ACCELERATION</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kocharov, L.; Laitinen, T.; Vainio, R.</p> <p>2015-06-10</p> <p>With the first observations of solar γ-rays from the decay of pions, the relationship of protons producing ground level enhancements (GLEs) on the Earth to those of similar energies producing the γ-rays on the Sun has been debated. These two populations may be either independent and simply coincident in large flares, or they may be, in fact, the same population stemming from a single accelerating agent and jointly distributed at the Sun and also in space. Assuming the latter, we model a scenario in which particles are accelerated near the Sun in a shock wave with a fraction transported backmore » to the solar surface to radiate, while the remainder is detected at Earth in the form of a GLE. <span class="hlt">Interplanetary</span> ions versus ions interacting at the Sun are studied for a spherical shock wave propagating in a radial <span class="hlt">magnetic</span> field through a highly turbulent radial ray (the acceleration core) and surrounding weakly turbulent sector in which the accelerated particles can propagate toward or away from the Sun. The model presented here accounts for both the first-order Fermi acceleration at the shock front and the second-order, stochastic re-acceleration by the turbulence enhanced behind the shock. We find that the re-acceleration is important in generating the γ-radiation and we also find that up to 10% of the particle population can find its way to the Sun as compared to particles escaping to the <span class="hlt">interplanetary</span> space.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860028042&hterms=Fast+radio+burst&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DFast%2Bradio%2Bburst','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860028042&hterms=Fast+radio+burst&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DFast%2Bradio%2Bburst"><span>Evidence of scattering effects on the sizes of <span class="hlt">interplanetary</span> Type III radio bursts</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Steinberg, J. L.; Hoang, S.; Dulk, G. A.</p> <p>1985-01-01</p> <p>An analysis is conducted of 162 <span class="hlt">interplanetary</span> Type III radio bursts; some of these bursts have been observed in association with fast electrons and Langmuir wave events at 1 AU and, in addition, have been subjected to in situ plasma parameter measurements. It is noted that the sizes of burst sources are anomalously large, compared to what one would anticipate on the basis of the <span class="hlt">interplanetary</span> plasma density distribution, and that the variation of source size with frequency, when compared with the plasma frequency variation measured in situ, implies that the source sizes expand with decreasing frequency to fill a cone whose apex is at the sun. It is also found that some local phenomenon near the earth controls the apparent size of low frequency Type III sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010cosp...38.2222F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010cosp...38.2222F"><span>Magnetosheath for almost-aligned solar wind <span class="hlt">magnetic</span> field and flow vectors: Windobservations across the dawnside magnetosheath at X = -12 Re</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farrugia, Charles</p> <p></p> <p>While there are many approximations describing the flow of the solar wind past the mag-netosphere in the magnetosheath, the case of perfectly aligned (parallel or anti-parallel) <span class="hlt">in-terplanetary</span> <span class="hlt">magnetic</span> field (IMF) and solar wind flow vectors can be treated exactly in an magnetohydrodynamic (MHD) approach (Spreiter and Rizzi, 1974). In this work we examine a case of nearly-opposed (to within 15 deg) <span class="hlt">interplanetary</span> field and flow vectors, which occurred on October 24-25, 2001 during passage of the last <span class="hlt">interplanetary</span> coronal mass ejection in an ejecta merger. <span class="hlt">Interplanetary</span> data are from the ACE spacecraft. Simultaneously Wind was crossing the near-Earth (X -13 Re) geomagnetic tail and subsequently made a 5-hour-long magnetosheath crossing close to the ecliptic plane (Z = -0.7 Re). Geomagnetic activity was returning steadily to quiet, "ground" conditions. We first compare the predictions of the Spre-iter and Rizzi theory with the Wind magnetosheath observations and find fair agreement, in particular as regards the proportionality of the <span class="hlt">magnetic</span> field strength and the product of the plasma density and bulk speed. We then carry out a small-perturbation analysis of the Spreiter and Rizzi solution to account for the small IMF components perpendicular to the flow vector. The resulting expression is compared to the time series of the observations and satisfactory agreement is obtained. We also present and discuss observations in the dawnside boundary layer of pulsed, high-speed (v 600 km/s) flows exceeding the solar wind flow speeds. We examine various generating mechanisms and suggest that the most likely causeis a wave of frequency 3.2 mHz excited at the inner edge of the boundary layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750004801','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750004801"><span>Features of polar cusp electron precipitation associated with a large <span class="hlt">magnetic</span> storm</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Berko, F. W.</p> <p>1974-01-01</p> <p>Measurements of precipitating electrons made by the OGO-4 satellite reveal several interesting phenomena in the polar cusp. Extremely high fluxes of 0.7 keV electrons were observed in the polar cusp ninety minutes following the sudden commencement of a very large <span class="hlt">magnetic</span> storm. Structured, fairly high fluxes of 7.3 keV electrons were also observed in the cusp region, accompanied by very strong search coil magnetometer fluctuations, indicative of strong field-aligned currents. The observations confirm previously reported latitudinal shifts in the location of the polar cusp in response to southward <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19800028904&hterms=1075&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2526%25231075','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19800028904&hterms=1075&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3D%2526%25231075"><span><span class="hlt">Interplanetary</span> dust - Trace element analysis of individual particles by neutron activation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ganapathy, R.; Brownlee, D. E.</p> <p>1979-01-01</p> <p>Although micrometeorites of cometary origin are thought to be the dominant component of <span class="hlt">interplanetary</span> dust, it has never been possible to positively identify such micrometer-sized particles. Two such particles have been identified as definitely micrometeorites since their abundances of volatile and nonvolatile trace elements closely match those of primitive solar system material.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AIPC..858..354Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AIPC..858..354Q"><span><span class="hlt">Interplanetary</span> Lyman α background and the heliospheric interface</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quémerais, Eric; Sander, Bill R.; Clarke, John T.</p> <p>2006-09-01</p> <p>We present some recent measurements of the <span class="hlt">interplanetary</span> Lyman α background which show a clear signature of the heliospheric interface. The Voyager 1 Ultraviolet Spectrometer has measured the variation of the upwind intensity from 1993 to 2006. The derived radial variation of the intensity is clearly slower than what is expected from a hot model computation. This shows that the hydrogen number density increases ahead of the spacecraft, toward the upwind direction. The data also show an abrupt change of slope in 1998 when the Voyager 1 spacecraft was at 65 AU from the sun. This may be linked to temporal variations induced at the heliospheric interface by the variations of solar activity. <span class="hlt">Interplanetary</span> Lyman α line profiles measured at one AU from the sun also show a clear signature of the heliospheric interface. The SWAN instrument on-board the SOHO spacecraft has studied the line profiles between 1996 and 2002. It was found that the variations seen in line of sight velocities from solar minimum to solar maximum have a larger amplitude than what is derived from hot model computations. The observed features can be better understood when considering that some of the hydrogen atoms crossing the interface region are slowed down and heated. These results are in good agreement with the present models of the interface. Independent spectral observations made by the Hubble Space Telescope in 1995-2001 confirm the SWAN/SOHO measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20110013494&hterms=Butterfly&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DButterfly','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20110013494&hterms=Butterfly&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DButterfly"><span><span class="hlt">Interplanetary</span> Shocks Lacking Type 2 Radio Bursts</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gopalswamy, N.; Xie, H.; Maekela, P.; Akiyama, S.; Yashiro, S.; Kaiser, M. L.; Howard, R. A.; Bougeret, J.-L.</p> <p>2010-01-01</p> <p>We report on the radio-emission characteristics of 222 <span class="hlt">interplanetary</span> (IP) shocks detected by spacecraft at Sun-Earth L1 during solar cycle 23 (1996 to 2006, inclusive). A surprisingly large fraction of the IP shocks (approximately 34%) was radio quiet (RQ; i.e., the shocks lacked type II radio bursts). We examined the properties of coronal mass ejections (CMEs) and soft X-ray flares associated with such RQ shocks and compared them with those of the radio-loud (RL) shocks. The CMEs associated with the RQ shocks were generally slow (<span class="hlt">average</span> speed approximately 535 km/s) and only approximately 40% of the CMEs were halos. The corresponding numbers for CMEs associated with RL shocks were 1237 km/s and 72%, respectively. Thus, the CME kinetic energy seems to be the deciding factor in the radio-emission properties of shocks. The lower kinetic energy of CMEs associated with RQ shocks is also suggested by the lower peak soft X-ray flux of the associated flares (C3.4 versus M4.7 for RL shocks). CMEs associated with RQ CMEs were generally accelerating within the coronagraph field of view (<span class="hlt">average</span> acceleration approximately +6.8 m/s (exp 2)), while those associated with RL shocks were decelerating (<span class="hlt">average</span> acceleration approximately 3.5 m/s (exp 2)). This suggests that many of the RQ shocks formed at large distances from the Sun, typically beyond 10 Rs, consistent with the absence of metric and decameter-hectometric (DH) type II radio bursts. A small fraction of RL shocks had type II radio emission solely in the kilometric (km) wavelength domain. Interestingly, the kinematics of the CMEs associated with the km type II bursts is similar to those of RQ shocks, except that the former are slightly more energetic. Comparison of the shock Mach numbers at 1 AU shows that the RQ shocks are mostly subcritical, suggesting that they were not efficient in accelerating electrons. The Mach number values also indicate that most of these are quasi-perpendicular shocks. The radio-quietness is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19950039553&hterms=neural+net&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dneural%2Bnet','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19950039553&hterms=neural+net&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dneural%2Bnet"><span>Neural net forecasting for geomagnetic activity</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hernandez, J. V.; Tajima, T.; Horton, W.</p> <p>1993-01-01</p> <p>We use neural nets to construct nonlinear models to forecast the AL index given solar wind and <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (IMF) data. We follow two approaches: (1) the state space reconstruction approach, which is a nonlinear generalization of autoregressive-moving <span class="hlt">average</span> models (ARMA) and (2) the nonlinear filter approach, which reduces to a moving <span class="hlt">average</span> model (MA) in the linear limit. The database used here is that of Bargatze et al. (1985).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21452847-major-electron-events-coronal-magnetic-configurations-related-solar-active-regions','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21452847-major-electron-events-coronal-magnetic-configurations-related-solar-active-regions"><span>MAJOR ELECTRON EVENTS AND CORONAL <span class="hlt">MAGNETIC</span> CONFIGURATIONS OF THE RELATED SOLAR ACTIVE REGIONS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Li, C.; Owen, C. J.; Matthews, S. A.</p> <p></p> <p>A statistical survey of 26 major electron events during the period 2002 February through the end of solar cycle 23 is presented. We have obtained electron solar onset times and the peak flux spectra for each event by fitting to a power-law spectrum truncated by an exponential high-energy tail, i.e., f(E){approx}E{sup -{delta}}e{sup -E/E{sub 0}}. We also derived the coronal <span class="hlt">magnetic</span> configurations of the related solar active regions (ARs) from the potential-field source-surface model. It is found that (1) 10 of the 11 well-connected open field-line events are prompt events whose solar onset times coincide with the maxima of flare emissionmore » and 13 of the 14 closed field-line events are delayed events. (2) A not-well-connected open field-line event and one of the closed field-line events are prompt events, they are both associated with large-scale coronal disturbances or dimming. (3) An <span class="hlt">averaged</span> harder spectrum is found in open field-line events compared with the closed ones. Specifically, the <span class="hlt">averaged</span> spectral index {delta} is of 1.6 {+-} 0.3 in open field-line events and of 2.0 {+-} 0.4 in closed ones. The spectra of three closed field-line events show infinite rollover energies E {sub 0}. These correlations clearly establish a significant link between the coronal <span class="hlt">magnetic</span> field-line topology and the escape of charged particles from the flaring ARs into <span class="hlt">interplanetary</span> space during the major solar energetic particle events.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14658294','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14658294"><span>[Some <span class="hlt">magnetic</span>-biological problems of distant and long-term space flights].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Trukhanov, K A</p> <p>2003-01-01</p> <p>Some magnetobiological problems of orbital (in the geomagnetic field--GMF) and <span class="hlt">interplanetary</span> (in hypomagnetic conditions) flights are considered. The influence of electromagnetic fields (EMF) created by systems and equipment of the space vehicle (SV) are touched also. A level of the geomagnetic field (GMF) onboard during the orbital flights is discussed. Its periodic variations onboard owing to movement of SV on an orbit are analyzed. The reader's attention in attracted to the papers by R.M. Baevsky et al. in which the influence of <span class="hlt">magnetic</span> storms and periodic variations of GMS on the cardiovascular system of astronauts onboard are shown. Possible ways and mechanisms of the influence are discussed. The wrong assertions in a number of works namely that at orbital flights an appreciable electrical field is induced in an organism of an astronaut in a space-craft and the electrical field may by responsible for some biological impacts are analyzed. The situation at the future in the terplanetary flights (for example Martian missions) when a crew and biological objects for a long time will be in the <span class="hlt">interplanetary</span> <span class="hlt">magnetic</span> field (by several orders less then GMF) is considered. As applied to the flights the opportunities of generation onboard the "artificial" GMF are outlined. The ensuing biological and technical questions are discussed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. 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