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Sample records for krievs leonids ribickis

  1. Leonid electrophonic bursters

    NASA Astrophysics Data System (ADS)

    Beech, M.; Foschini, L.

    2001-03-01

    We investigate the conditions under which Leonid meteoroids might generate short duration (burster) electrophonic sounds. A ``first order'' theory is employed to estimate the approximate electron number density in the meteoroid ablation column as a function of time. Using the threshold conditions discussed in an earlier communication (Beech & Foschini \\cite{BEECH99fo}) we find that Leonid meteoroids more massive than about 0.1 kg can potentially generate short duration electrophonic bursters.

  2. Leonid STIS proposal

    NASA Astrophysics Data System (ADS)

    Baum, Stefi

    1997-07-01

    We propose to obtain STIS G750L slitless spectroscopy and a 50CCD image of the field around the quasar PKS 2200-238 during the Leonid meteor shower to identify high redshift galaxies associated with Lyman-alpha and metal absorption systems in the quasar spectrum. Our key aim is to achieve the direct optical identification of high redshift galaxies which produce absorption against the background QSO. Whilst there are many direct detections of Lyman alpha absorbing galaxies at low-intermediate redshifts {z<0.7; see Lanzetta et al 1995, ApJ, 442, 538}, there are currently no direct identifications of galaxies giving rise to Lyman-a forest lines at high redshifts. It is important to do this in order to understand the nature of Lyman forest absorbers over all redshifts, particularly in light of recent results claiming the existence of a break in the redshift distribution {dn/dz} for Lyman-a forest absorbers around z=1.7 {Weymann et al 1998, ApJ, 506}. Such a feature in the redshift distribution might indicate the onset of a new population of objects. The observations proposed here will address this issue.

  3. 1997 Leonid Shower From Space

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Nugent, David; Murthy, Jayant; Tedesco, Ed; DeVincenzi, Donal L. (Technical Monitor)

    2000-01-01

    In November 1997, the Midcourse Space Experiment satellite (MSX) was deployed to observe the Leonid shower from space. The shower lived up to expectations, with abundant bright fireballs. Twenty-nine meteors were detected by a wide-angle, visible wavelength, camera near the limb of the Earth in a 48-minute interval, and three meteors by the narrow field camera. This amounts to a meteoroid influx of 5.5 +/- 0.6 10(exp -5)/sq km hr for masses greater than 0.3 gram. The limiting magnitude for limb observations of Leonid meteors was measured at M(sub v) = -1.5 magn The Leonid shower magnitude population index was 1.6 +/- 0.2 down to M(sub v) = -7 magn., with no sign of an upper mass cut-off.

  4. 1997 Leonid Shower from Space

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter; Nugent, David; Tedesco, Ed; Murthy, Jayant

    In November 1997, the Midcourse Space Experiment satellite (MSX) was deployed to observe the Leonid shower from space. The shower lived up to expectations, with abundant bright fireballs. Twenty-nine meteors were detected by a wide-angle, visible wavelength, camera near the limb of the Earth in a 48-minute interval, and three meteors by the narrow field camera. This amounts to a meteoroid influx of 5.5 +/- 0.6 10^-5 km^-2 hr^-1 for masses > 0.3 gram. The limiting magnitude for limb observations of Leonid meteors was measured at M_v = -1.5 magn. The Leonid shower magnitude population index was 1.6 +/- 0.2 down to M_v = -7 magn., with no sign of an upper mass cut-off.

  5. Video Observations Of Leonids 1999

    NASA Astrophysics Data System (ADS)

    Molau, Sirko; Rendtel, Jürgen; Bellot-Rubio, Luis Ramon

    1999-07-01

    We analyse data obtained by different ground-based video camera systems during the 1999 Leonid meteor storm. We observe similar activity profiles at nearby observing sites, but significant differences over distances in the order of 4,000 km. The main peak occured at 02:03 UT (λ⊙=235.286, J2000, corrected for the time of the topocentric stream encounter). At the Iberian peninsula quasi-periodic activity fluctuations with a period of about 7 min were recorded. The camera in Jordan detected a broad plateau of activity at 01:39-01:53 UT, but no periodic variations. The Leonid brightness distribution derived from all cameras shows a lack of faint meteors with a turning point close to +3m, which corresponds to meteoroids of approximately 10-3 g. We find a pin-point radiant at αalpha=153.65 ±0.1, δ=21.80 ±0. (λ⊙=235.290). The radiant positionis identical before and after the storm, and also during the storm no driftis observed.

  6. Photographic Leonids 1998 Observed at Modra Observatory

    NASA Astrophysics Data System (ADS)

    Tóth, Juraj; Kornoš, Leonard; Porubčan, Vladimir

    Results of photographic observations of the 1998 Leonids performed at Modra Observatory (Slovakia) are presented and discussed. During an exposure time of 7 hr 14 min on November 16/17 a total of 168 meteors were recorded. Photographic rates of bright Leonid meteors as well as their magnitude distribution are presented and compared with the results obtained by other techniques. The photographic 1998 Leonids exhibit a maximum at the solar longitude 234.52°, Equinox 2000.0 (Nov. 17, 01:40 UT).

  7. Search for Organic Matter in Leonid Meteoroids

    NASA Technical Reports Server (NTRS)

    Rairden, Richard L.; Jenniskens, Peter; Laux, Christophe O.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Near-ultraviolet 300-410 nm spectra of Leonid meteors were obtained in an effort to measure the strong B to X emission band of the radical CN in Leonid meteor spectra at 387 nm. CN is an expected product of ablation of nitrogen containing organic carbon in the meteoroids as well as a possible product of the aerothermochemistry induced by the kinetic energy of the meteor. A slitless spectrograph with objective grating was deployed on FISTA during the 1999 Leonid Multi-Instrument Aircraft Campaign. Fifteen first-order UV spectra were captured near the 02:00 UT meteor storm peak on November 18. It is found that neutral iron lines dominate the spectrum, with no clear sign of the CN band. The meteor plasma contains less than one CN molecule per three Fe atoms at the observed altitude of about 100 km.

  8. The Leonid Fireball Night from Romania

    NASA Astrophysics Data System (ADS)

    Grigore, V.; Berinde, S.

    1999-02-01

    An overview of the 1998 Leonid activity as seen from Romania by SARM members, with a description of the event on November 16-17 as seen by Valentin Grigore (GRIVA) at Targoviste, lambda=25deg 29' 00'' E, phi=44deg 57' 18'' N, h=350m.

  9. Metallic abundances of the 2002 Leonid

    NASA Astrophysics Data System (ADS)

    Kasuga, T.; Yamamoto, T.; Watanabe, J.; Yano, H.

    The Leonid meteor shower is caused by the Earth's encountering dust trails ejected from Comet 55P/Tempel-Tuttle. After the return of this comet in 1998, a theoretical calculation predicted that the peak activities could go up to a `storm' level in next five years. From the latest study of comets, the measurements of the HDO/H2O ratio imply the possibility of delivering volatile materials to the Earth by cometary dust grains. To explore the possibility of delivering water and pre-biotic organics to the Earth, we developed a HDTV spectroscopic observational system. The system was focused on the near - ultraviolet wavelength range (300 nm - 600 nm) by combining reflective grating, UV lens (f=30 mm, F1.4), Image Intensifier (I.I.), and High Definition TV camera (HDTV). The field of view (FOV) was 23° × 13°, and the observable wavelength range was in 300 nm - 900 nm, with resolution of 1.0 - 1.5 nm. By using this system, we carried out spectroscopic observations at the SUBARU Telescope site and the Nobeyama Radio observatory site in 2001. In 2002, we participated in NASA's Leonid Multi - Instrument Aircraft Campaign (Leonid MAC), which had started since 1998. This campaign concept is to bring together world-wide scientists from different disciplines and cooperatively observe the Leonid meteors using a wide range of techniques. Scientists were divided into two airplanes. The one was the NASA DC-8 Airborne Laboratory, and the other one was FISTA. The route of the both aircrafts was from Torrejon, Spain to Offutt, Nebraska in order to encounter two predicted peaks. This observation also could decrease air extinction and Rayleigh scattering in the ultraviolet region. The High-Definition TV spectra in the visual--ultraviolet region were obtained during the 2002 Leonid aircraft campaign. The ultraviolet wavelengths of between 300--600 nm were observed, and the metallic atoms were identified, mainly MgI, MgII, FeI, CaI, CaII, NiI, NaI and MnI. From the analysis of the

  10. Leonid Pavlovich Shil'nikov (obituary)

    NASA Astrophysics Data System (ADS)

    Anosov, Dmitry V.; Afraimovich, Valentin S.; Bunimovich, Leonid A.; Gonchenko, Sergei V.; Grines, Vyacheslav Z.; Ilyashenko, Yulij S.; Katok, Anatolii B.; Kashchenko, Sergey A.; Kozlov, Valerii V.; Lerman, Lev M.; Morozov, Albert D.; Neishtadt, Anatolii I.; Pesin, Yakov B.; Samoilenko, Anatoly M.; Sinai, Yakov G.; Treschev, Dmitrii V.; Turaev, Dmitry V.; Sharkovskii, Aleksandr N.; Shil'nikov, Andrei L.

    2012-06-01

    A remarkable mathematician, one of the most prominent specialists in the theory of dynamical systems and bifurcation theory, a laureate of the Lyapunov Prize of the Russian Academy of Sciences and of the Lavren'ev Prize of the National Academy of Sciences of Ukraine, a Humboldt Professor, Head of the Department of Differential Equations of the Research Institute of Applied Mathematics and Cybernetics of Nizhnii Novgorod University, Professor Leonid Pavlovich Shil'nikov passed away on 26 December 2011.

  11. Leonid Storm Flux Analysis from One Leonid Mac Video AL50R

    NASA Astrophysics Data System (ADS)

    Gural, Peter S.; Jenniskens, Peter

    A detailed meteor flux analysis is presented of a seventeen-minute portion of one videotape, collected on November 18, 1999, during the Leonid Multi-instrument Aircraft Campaign. The data was recorded around the peak of the Leonid meteor storm using an intensified CCD camera pointed towards the low southern horizon. Positions of meteors on the sky were measured. These measured meteor distributions were compared to a Monte Carlo simulation, which is a new approach to parameter estimation for mass ratio and flux. Comparison of simulated flux versus observed flux levels, seen between 1:50:00 and 2:06:41 UT, indicate a magnitude population index of r = 1.8 +/- 0.1 and mass ratio of s = 1.64 +/- 0.06. The average spatial density of the material contributing to the Leonid storm peak is measured at 0.82 +/- 0.19 particles per square kilometer per hour for particles of at least absolute visual magnitude +6.5. Clustering analysis of the arrival times of Leonids impacting the earth's atmosphere over the total observing interval shows no enhancement or clumping down to time scales of the video frame rate. This indicates a uniformly random temporal distribution of particles in the stream encountered during the 1999 epoch. Based on the observed distribution of meteors on the sky and the model distribution, recommendations are made for the optimal pointing directions for video camera meteor counts during future ground and airborne missions.

  12. Leonid Storm Flux Analysis From One Leonid MAC Video AL50R

    NASA Technical Reports Server (NTRS)

    Gural, Peter S.; Jenniskens, Peter; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    A detailed meteor flux analysis is presented of a seventeen-minute portion of one videotape, collected on November 18, 1999, during the Leonid Multi-instrument Aircraft Campaign. The data was recorded around the peak of the Leonid meteor storm using an intensified CCD camera pointed towards the low southern horizon. Positions of meteors on the sky were measured. These measured meteor distributions were compared to a Monte Carlo simulation, which is a new approach to parameter estimation for mass ratio and flux. Comparison of simulated flux versus observed flux levels, seen between 1:50:00 and 2:06:41 UT, indicate a magnitude population index of r = 1.8 +/- 0.1 and mass ratio of s = 1.64 +/- 0.06. The average spatial density of the material contributing to the Leonid storm peak is measured at 0.82 +/- 0.19 particles per square kilometer per hour for particles of at least absolute visual magnitude +6.5. Clustering analysis of the arrival times of Leonids impacting the earth's atmosphere over the total observing interval shows no enhancement or clumping down to time scales of the video frame rate. This indicates a uniformly random temporal distribution of particles in the stream encountered during the 1999 epoch. Based on the observed distribution of meteors on the sky and the model distribution, recommendations am made for the optimal pointing directions for video camera meteor counts during future ground and airborne missions.

  13. Video Observation of the Leonids 2001 Activity

    NASA Astrophysics Data System (ADS)

    Lin, Chilong; Abe, Shinsuke; Koten, Pavel; Yang, I-Ching

    2012-02-01

    This paper presents an analysis of records obtained by video equipment of the 2001 Leonid meteor storm. Totally, 3712 meteors, including 22 non-Leonid ones, were recognized from the record of 247 min. The brightness of meteors was measured with the software ``LIMovie'', and a population index of r = 2.01 ± 0.05 (-8 ≤ mag ≤ -3) was thus derived. We proposed a way to derive the mass-distribution index, s = 1.82, from only our one-station data. The maximum of the activity appeared at 18h25m UT with an effective peak of ZHR90°×67° = 52606 (mag ≤ +6.5). There are also compatible sub-peaks and high plateaus beside the main peak. One of them may correspond to the predicted 9-revolution dust trail (ejection in 1699). In this article we treat the cross section of the influx zone as a trapezoid. The peak ``influx rate'' generated by the 4-revolution dust trail (ejection in 1866) thus derived would be 6.76 × 10-5km-2s-1 (mag ≤ +6.5), and the corresponding ``spatial number density'' would be 9.52 × 10-7km-3 (mag ≤ +6.5).

  14. Comet Tempel-Tuttle and the Leonid meteors

    NASA Technical Reports Server (NTRS)

    Yeomans, D. K.

    1981-01-01

    The distribution of dust surrounding periodic comet Tempel-Tuttle has been mapped by analyzing the associated Leonid meteor shower data over the 902-1969 interval. The majority of dust ejected from the parent comet evolves to a position lagging the comet and outside the comet's orbit. Hence, it appears that radiation pressure and planetary perturbations, rather than ejection processes, control the dynamic evolution of the Leonid particles. Significant Leonid meteor showers are possible roughly 2500 days before or after the parent comet reaches perihelion, but only if the comet passes closer than 0.025 AU inside or 0.010 AU outside the earth's orbit. Although the conditions in 1998-1999 are optimum for a significant Leonid meteor shower, the event is not certain because the dust particle distribution near the comet is far from uniform. The orbit of comet Tempel-Tuttle has been redetermined for the 1366-1966 observed interval.

  15. Observations of Leonids 2009 by the Tajikistan Fireball Network

    NASA Technical Reports Server (NTRS)

    Borovicka, J.; Borovicka, J.

    2011-01-01

    The fireball network in Tajikistan has operated since 2009. Five stations of the network covering the territory of near eleven thousands square kilometers are equipped with all-sky cameras with the Zeiss Distagon "fish-eye" objectives and by digital SLR cameras Nikon with the Nikkor "fish-eye" objectives. Observations of the Leonid activity in 2009 were carried out during November 13-21. In this period, 16 Leonid fireballs have been photographed. As a result of astrometric and photometric reductions, the precise data including atmospheric trajectories, velocities, orbits, light curves, photometric masses and densities were determined for 10 fireballs. The radiant positions during the maximum night suggest that the majority of the fireball activity was caused by the annual stream component with only minor contribution from the 1466 trail. According to the PE criterion, the majority of Leonid fireballs belonged to the most fragile and weak fireball group IIIB. However, one detected Leonid belonged to the fireball group I. This is the first detection of an anomalously strong Leonid individual.

  16. Very Precise Orbits of 1998 Leonid Meteors

    NASA Technical Reports Server (NTRS)

    Betlem, Hans; Jenniskens, Peter; vantLeven, Jaap; terKuile, Casper; Johannink, Carl; Zhao, Hai-Bin; Lei, Chen-Ming; Li, Guan-You; Zhu, Jin; Evans, Steve; DeVincenzi, Donald L. (Technical Monitor)

    1999-01-01

    Seventy-five orbits of Leonid meteors obtained during the 1998 outburst are presented. Thirty-eight are precise enough to recognize significant dispersion in orbital elements. Results from the nights of 1998 November 16/17 and 17/18 differ, in agreement with the dominant presence of different dust components. The shower rate profile of 1998 November 16/17 was dominated by a broad component, rich in bright meteors. The radiant distribution is compact. The semimajor axis is confined to values close to that of the parent comet, whereas the distribution of inclination has a central condensation in a narrow range. On the other hand, 1998 November 17/18 was dominated by dust responsible for a more narrow secondary peak in the flux curve. The declination of the radiant and the inclination of the orbit are more widely dispersed. The argument of perihelion, inclination, and the perihelion distance are displaced. These data substantiate the hypothesis that trapping in orbital resonances is important for the dynamical evolution of the broad component.

  17. The Leonid Meteors and Space Shuttle Risk Assessment

    NASA Technical Reports Server (NTRS)

    Pawlowski, James F.; Hebert, Thomas

    2000-01-01

    The November 1999 Leonid meteor shower was videotaped on the grounds of the NASA Johnson Space Center (JSC) and at the JSC Observatory in Cloudcroft, New Mexico. The videotapes were analyzed using a meteor analysis system developed at JSC. The results of the analysis were compared to the Leonid Meteors Mass Distribution Model derived at JSC and used for micrometeoroid and orbital debris risk assessment performed before each Space Shuttle mission. The observed data compared favorably to the model in the .001 to 0.2 gram range but diverged from the model for the smaller masses. We attribute the divergence to optical equipment limitations. These 1999 results will be compared with the 1998 results which were presented at the April 1999 Leonid Multi-Instrument Aircraft Campaign (MAC) Workshop.

  18. The 2002 Leonid MAC Airborne Mission: First Results

    NASA Astrophysics Data System (ADS)

    Jenniskens, P.

    2002-12-01

    The NASA- and USAF-sponsored 2002 Leonid Multi-Instrument Campaign consisted of two instrumented aircraft that flew from Madrid, Spain, to Omaha, Nebraska, with 38 researchers on board to cover the two Leonid storm peaks. Both aircraft were above clouds and under perfect observing conditions, with a radiant climbing from 35 to 67 degree elevation and the full Moon relatively low in the sky. All instruments worked as expected and aurora, moon, and meteors made the view scenic and truly spectacular at times. This report is a brief impression of the mission and a first look at some of the results in the weeks following the campaign.

  19. The Leonid Meteors and Space Shuttle Risk Assessment

    NASA Astrophysics Data System (ADS)

    Pawlowski, James F.; Hebert, Thomas T.

    The November 1999 Leonid meteor shower was videotaped with a low light level camera from the grounds of the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) in Houston, Texas. Additionally, observations of the Leonids were recorded both digitally with the Liquid Mirror Telescope (LMT) and with a low light level camera at the JSC Observatory near Cloudcroft, New Mexico. The tapes were analyzed using a computer-automated meteor analysis system developed at JSC. These results were used to form estimates of the Leonid mass-distribution. These estimates were compared to a Leonid mass distribution model used by NASA in risk assessment calculations associated with Space Shuttle missions. The observed data agrees favorably with the NASA model in the 0.002 to 0.02 milligram range (based upon the LMT observations) and in the 0.02 to 0.2 gram range (based upon the low light level camera observations). This comparison supports the continued use of this model.

  20. Leonid Dust Spheres Captured During the 2002 Storm?

    NASA Technical Reports Server (NTRS)

    Rietmeijer, Frans J. M.; Pfeffer, Melissa A.; Chizmadia, Lysa; Macy, B.; Fischer, T. P.; Zolensky, M. E.; Warren, J. L.; Jenniskens, P.

    2003-01-01

    An effort was made to collect dust from a known source, comet 55P/Tempel-Tuttle, in the form of Leonid meteor debris in the hours after the 2002 storm. No interplanetary dust particles (IDPs) have yet been recovered from a known source. We do not expect Leonid debris at 72 km/s to survive atmospheric entry as aggregates and our effort was predicated on the notion that mm-sized and larger meteoroids after extreme mass could survive as up to approximately 100 micron-sized silicate spheres. Two anticipated Leonid storms, rather than its annual shower activity, were the target of the last Leonid Multi-Aircraft Campaign during the Nov. 19, 2002 storm. Flying westwards from Spain to the US the mission covered both the 1767 and 1866 dust trails whereby early in the flight the aircraft flew several hours across the region exposed to the first storm peak that did not include the continental US of the second peak with 5,400 meteors.

  1. Visual Observations of the 1998 and 1999 Leonids in Israel

    NASA Astrophysics Data System (ADS)

    Mikishev, Alex; Levina, Anna

    Results from visual observations of the Leonid showers in 1998 and 1999 in Israel are presented. They were processed by the method which was developed at Engelhardt Astronomical Observatory (Kazan, Russia). The values of the mass index and the Zenithal hourly rate (ZHR) are estimated for both showers. The peak of the 1999 shower was over the Middle East and the conditions for observation were optimal. The calculated ZHR for 1999 Leonid shower was up to ZHR ~ 3,700 based on 2-minute intervals, while the peak time was at solar longitude λ_o = 235.281 +/- 0.001 (J2000), which corresponds to 1^h57^m +/- 2^m UT November 18. The shower width was 0.032 +/- 0.002 ° solar longitude. The population index was higher during the storm of 1999 than in 1998.

  2. Activity of the 1998 Leonid Shower From the Video Records

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter

    1999-01-01

    Video observations of the Leonid shower aboard two aircraft in the 1998 Leonid multi-instrument aircraft campaign and from ground locations in China are presented. Observing at altitude proved particularly effective, with four times higher rates due to low extinction and low angular velocity at the horizon. The rates, derived from a total of 2500 Leonid meteors, trace at least two distinct dust components. One dominated the night of 1998 November 16/17. This two-day wide component was rich in bright meteors with r = N (m + 1)/N (m) approximately equal 1.5 (s = 1.4) and peaked at an influx of 3.1 +/- 0.4 x 10(exp -12) /sq m.s (for particles of mass < 7 x 10(exp -5) g) at solar longitude lambda(sub 0) approximately equal 234.52 (Eq. J2000). The other more narrow component peaked on 1998 November 17/18 at lambda(sub 0) = 235.31 +/- 0.01. Rates were elevated above the broad component between lambda(sub 0) = 235.15 and 235.40, symmetric around the current node of the parent comet 55P/Tempel-Tuttle, peaking at 5.1 +/- 0.2 x 10(exp -12) /sq m.s. The population index was higher, r = 1.8 +/- 0.1 (s = 1.7), but not as high as in past Leonid storms (r = 3.0). The flux profile of this component has an unusual asymmetric shape, which implies a blend of contributions from at least two different but relatively recent epochs of ejection. The variation of r across the profile might be due to mass-dependent ejection velocities of the narrowest component. High rates of faint meteors occurred only in an isolated five-minute interval at lambda(sub 0) = 235.198, which is likely the result of a single meteoroid breakup in space.

  3. Possible satellite-based observations of the 1997 Leonid meteoroids

    SciTech Connect

    Pongratz, M.B.; Carlos, R.C.; Cayton, T.

    1998-12-01

    The Block IIA GPS satellites are equipped with a sensor designed to detect electromagnetic transients. Several phenomena will produce triggers in this sensor. They include earth-based electromagnetic transients such as lightning and two space-based phenomena--deep dielectric discharge and meteoroid or hyper-velocity micro-gram particle impact (HMPI). Energetic electrons in the GPS environment cause the deep dielectric charging. HMPIs cause triggers through the transient electric fields generated by the ejecta plasma. During the 1997 Leonid passage the energetic particle fluxes were very low. In the presence of such low fluxes the typical median trigger rate is 20 per minute with a standard deviation of about 20 per minute. Between 0800 UT and 1200 UT on November 17, 1997, the sensor on a specially configured satellite observed trigger rates more than 10 sigma above the nominal median rate. Sensors on other Block IIA GPS satellites also observed excess triggers during November. Detection is enhanced when the sensor antenna is oriented into the Leonid radiant. While many questions persist the authors feel that it is likely that the excess events during the November interval were caused by the close approach of the satellites to the Leonid meteoroid path.

  4. Fluctuations in the Activity Curve of the 2002 Leonids

    NASA Astrophysics Data System (ADS)

    Ruiz Herrera, Lola; Bellot Rubio, Luis R.; Serra-Ricart, Miquel

    We present observations of the 2002 Leonid meteor shower taken with four intensified video cameras from Teide Observatory (Tenerife Spain) on November 19 2002. The cameras fitted with f/1.4 85 mm objectives were aimed at 6 deg above the horizon in order to monitor the largest atmospheric volume possible. The most sensitive camera detected 1300 meteors between 0312 and 0456 UT i.e. the period covering the European Leonid storm of 2002. The activity curve constructed from these data peaks at 0401 UT about 9 minutes earlier than indicated by the visual observations analyzed by the International Meteor Organization. Our results thus favor the model of Lyytinen and van Flandern who predicted the first maximum at 0402 UT. We find statistically significant oscillations in the activity curve. A Fourier analysis delivers a period of about 7 minutes. These observations confirm the discovery of Singer et al. (2000) that density fluctuations exist in the Leonid dust trails at spatial scales of 10000-30000 km. The oscillations we observe are very similar to those detected by Singer et al. the only difference being that the dust trail is 132 years older.

  5. Fluctuations in the activity curve of the 2002 Leonids

    NASA Astrophysics Data System (ADS)

    Herrara Ruiz, Lola; Rubio Bellot, Luis R.; Serra-Ricart, Miquel

    2005-01-01

    We present observations of the 2002 Leonid meteor shower taken with four intensified video cameras from Teide Observatory (Tenerife Spain) on November 19 2002. The cameras fitted with f/1.4 85 mm objectives were aimed at 6 deg above the horizon in order to monitor the largest atmospheric volume possible. The most sensitive camera detected 1300 meteors between 0312 and 0456 UT i.e. the period covering the European Leonid storm of 2002. The activity curve constructed from these data peaks at 0401 UT about 9 minutes earlier than indicated by the visual observations analyzed by the International Meteor Organization. Our results thus favor the model of Lyytinen and van Flandern who predicted the first maximum at 0402 UT. We find statistically significant oscillations in the activity curve. A Fourier analysis delivers a period of about 7 minutes. These observations confirm the discovery of Singer et al. (2000) that density fluctuations exist in the Leonid dust trails at spatial scales of 10000-30000 km. The oscillations we observe are very similar to those detected by Singer et al. the only difference being that the dust trail is 132 years older.

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    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-18

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  7. Comparison of 1998 and 1999 Leonid Light Curve Morphology and Meteoroid Structure

    NASA Technical Reports Server (NTRS)

    Murray, Ian S.; Beech, Martin; Taylor, Michael J.; Jenniskens, Peter; Hawkes, Robert L.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Photometric low-light level video observations of 1999 Leonid storm meteors have been obtained from airborne platforms during the Leonid multi-instrument aircraft campaign (Leonid MAC). The 1999 Leonid light curves tend to be skewed towards the end point of the trajectory, while the 1998 Leonid light curves were not. The variation in the light curves from 1998 and 1999 can be explained as an overall reduction in the mass distribution index, alpha from approximately 1.95 in 1998 to approximately 1.75 in 1999. We have interpreted this behavior as being either indicative of a gradual loss of the "glue" that keeps the grains together, or the fact that the meteoroids sampled in 1998 had a different morphological structure to those sampled in 1999. The early fragmentation of a dustball meteoroid results in a light curve that peaks sooner than that predicted by classical single body ablation theory.

  8. Results from 2002 Leonid meteor storm TV observations in Kyiv

    NASA Astrophysics Data System (ADS)

    Kozak, P. M.; Rozhilo, O. O.; Kruchynenko, V. G.; Kazantsev, A. M.; Taranukha, Y. G.

    Results are presented from double-station TV observations of the 2002 Leonids meteor storm as seen from Kyiv (Ukraine). The observations were carried out from two observational stations 54 km apart. The total observation time was five hours: from 23:30 till 4:30 UT on 18/19 November, 2002. The total number of two-station meteors was 38, 28 of which allowed for precise processing. The trajectories of the meteors in Earth’s atmosphere, their radiant coordinates, heliocentric orbital elements, etc., were calculated. The highest beginning height observed was 151.53 ± 2.79 km, and distributions of beginning and end heights are presented. Leonids registered during the onset of the storm between 3:00 and 4:00 UT had geocentric radiants (J2000.0) concentrated into a compact group with mean RA = 154°.43 ± 0°.55 and Decl. = 21°.91 ± 0°.58. The corresponding mean inclination and argument of perihelion of the orbit are i = 162°.62 ± 0°.61 and ω = 175°.13 ± 1°.37, respectively. The initial masses of meteoroids were calculated from photometry, from which a mass distribution index s = 1.43 ± 0.02 was derived. We determined that the number of meteors brighter than 4m (1.54 × 10-4 g) that crossed a horizontal circular area of radius 100 km at an altitude of 100 km, for an assumed radiant in zenith, changed during the observations from 350/h to 1400/h. The corresponding spatial density of Leonid stream particles was 4.3 × 10-8 1.7 × 10-7 km-3.

  9. Forecast for the Remainder of the Leonid Storm Season

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The dust trails of comet 55P/Tempel-Tuttle lead to Leonid storms on Earth, threatening satellites in orbit. We present a new model that accounts in detail for the observed properties of dust tails evolved by the comet at previous oppositions. The prediction model shows the 1767-dust trail closer to Earth's orbit in 2001 than originally thought; increasing expected peak rates for North America observers. Predictions for the 2002 storms are less affected. We demonstrate that the observed shower profiles can be understood as a projection of the comet lightcurve.

  10. The 2002 Leonid Multi-Instrument Aircraft Campaign

    NASA Astrophysics Data System (ADS)

    Jenniskens, P.

    2003-04-01

    The final mission in the NASA and USAF sponsored Leonid Multi-Instrument Campaign consisted of two instrumented aircraft that flew from Madrid, Spain, to Omaha, Nebraska, putting 38 participating researchers from seven nationalities in a position to study both November 19, 2002, Leonid meteor storms under excellent observing conditions. Two storms were anticipated to result from Earth's encounter with dust ejected by comet 55P/Tempel-Tuttle in 1767 and 1866 (peak at 04:00 and 10:40 UT). Planetary perturbations directed these dust trails in Earth's path. The mission was deployed out of Torrejon de Ardoz, near Madrid, where we were hosted by the Centro de Astrobiologia. In the night of November 19, both aircraft were above clouds en route to Omaha, with a radiant climbing from 35 to 67 degrees and the full Moon relatively low in the sky. All instruments worked as expected. Meteor storms were observed peaking at 04:06 and 10:47 UT, much as predicted. The presentations is a brief overview of experiments and first results, which include new insight into comet dust trail formation and dynamics, comet mass loss, and measurements of elemental abundances of cometary dust and of grain morphology.

  11. Russian Revolutions, Lenin and Trotzky in a Book by Leonid Dobronravov (Donitch)

    NASA Astrophysics Data System (ADS)

    Gaina, Alex

    Some reflections concerning the role of Communist Party in the development of sciences and arts in the Soviet Union, following from the book by Leonid Dobronravov (Donitch)(Russian Revolution) and writings by Gennady Gorelik are given.

  12. Complex Traits and Simple Systems: An Interview with Leonid Kruglyak.

    PubMed

    Kruglyak, Leonid

    2016-07-01

    The Genetics Society of America's Edward Novitski Prize recognizes an extraordinary level of creativity and intellectual ingenuity in the solution of significant problems in genetics research. The 2016 winner, Leonid Kruglyak, has made innovative contributions to the fields of linkage analysis, population genetics, and genomics, while drawing on a combination of mathematical, computational, and experimental approaches. Among other achievements, his work on statistical standards for genome-wide linkage studies has transformed their experimental design, and the linkage analysis program GENEHUNTER has been used to identify hundreds of human disease loci. Kruglyak's group also pioneered expression quantitative trait locus studies, which enabled variation in global gene expression to shed light on the genetics of complex human diseases. In recent years, his laboratory has focused on using genomic technology to establish Saccharomyces cerevisiae and Caenorhabditis elegans as model organisms for studies of complex genetic variation. PMID:27384025

  13. Formation of the Leonid meteor stream and storm

    NASA Technical Reports Server (NTRS)

    Wu, Zidian; Williams, I. P.

    1992-01-01

    It is well known that some meteor showers display a very high level of activity at certain times, the most famous being the Leonid shower with very spectacular displays at roughly 33 year intervals. This period being also the period of the parent comet of the stream, Comet Tempel-Tuttle. An investigation of the geometry of the comet and the Earth at the time of each high activity occurrence by Yeomans suggests that most of the meteoroids are found outside the cometary orbit and lagging the comet. The formation process of such a stream by numerically integrating the orbits of dust particles ejected from the comet and moving under the influence of gravity and radiation pressure are simulated. The intersection of these dust particles with the Earth is also considered and it is concluded that about 12 percent of the ejected particles may be observed and that of those observable, 63 percent will be outside the cometary orbit and behind the comet.

  14. STS-87 Payload Specialist Leonid K. Kadenyuk suits up

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine gives a thumbs up in his launch and entry suit in the Operations and Checkout Building. He and the five other crew members of STS-87will depart shortly for Launch Pad 39B, where the Space Shuttle Columbia awaits liftoff on a 16-day mission to perform microgravity and solar research. Kadenyuk will be flying his first mission on STS-87. During the mission, Kadenyuk will pollinate Brassica rapa plants as part of the Collaborative Ukrainian Experiment, or CUE, aboard Columbia. The CUE experiment is a collection of 10 plant space biology experiments that will fly in Columbias middeck and features an educational component that involves evaluating the effects of microgravity on Brassica rapa seedlings.

  15. Mid-Infrared Spectroscopy of Persistent Leonid Trains

    NASA Technical Reports Server (NTRS)

    Russell, Ray W.; Rossano, George S.; Chatelain, Mark A.; Lynch, David K.; Tessensohn, Ted K.; Abendroth, Eric; Kim, Daryl; Jenniskens, Peter; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The first infrared spectroscopy in the 3-13 micron region has been obtained of several persistent Leonid meteor trains with two different instrument types, one at a desert ground-based site and the other on-board a high-flying aircraft. The spectra exhibit common structures assigned to enhanced emissions of warm CH4, CO2, CO and H2O which may originate from heated trace air compounds or materials created in the wake of the meteor. This is the first time that any of these molecules has been observed in the spectra of persistent trains. Hence, the mid-IR observations offer a new perspective on the physical processes that occur in the path of the meteor at some time after the meteor itself has passed by. Continuum emission is observed also, but its origin has not yet been established. No 10 micron dust emission feature has been observed.

  16. Observations of Leonid Meteors Using a Mid-Wave Infrared Imaging Spectrograph

    NASA Astrophysics Data System (ADS)

    Rossano, George S.; Russell, Ray W.; Lynch, David K.; Tessensohn, Ted K.; Warren, David; Jenniskens, Peter

    We report broadband 3-5.5 µm detections of two Leonid meteors observed during the 1998 Leonid Multi-Instrument Aircraft Campaign. Each meteor was detected at only one position along their trajectory just prior to the point of maximum light emission. We describe the particular aspects of the Aerospace Corp. Mid-wave Infra-Red Imaging Spectrograph (MIRIS) developed for the observation of short duration transient events that impact its ability to detect Leonid meteors. This instrument had its first deployment during the 1998 Leonid MAC. We infer from our observations that the mid-wave IR light curves of two Leonid meteors differed from the visible light curve. At the points of detection, the infrared emission in the MIRIS passband was 25 +/- 4 times that at optical wavelengths for both meteors. In addition, we find an upper limit of 800 K for the solid body temperature of the brighter meteor we observed, at the point in the trajectory where we made our mid-wave IR detection.

  17. C-H Hot Bands in the Near-IR Emission Spectra of Leonids

    NASA Technical Reports Server (NTRS)

    Freund, F. T.; Scoville, J.; Holm, R.; Seelemann, R.; Freund, M. M.

    2002-01-01

    The reported infrared (IR) emission spectra from 1999 Leonid fireballs show a 3.4 micron C-H emission band and unidentified bands at longer wavelengths. Upon atmospheric entry, the Leonid meteorites were flash-heated to temperatures around 2400K, which would destroy any organics on the surface of the meteorite grains. We propose that the nu(sub )CH emission band in the Leonid emission spectra arises from matrix-embedded C(sub n)-H-O entities that are protected from instant pyrolysis. Our model is based on IR absorption nu(sub )CH bands, which we observed in laboratory-grown MgO and natural olivine single crystals, where they arise from C(sub n)-H-O units imbedded in the mineral matrix, indicative of aliphatic -CH2- and -CH3 organics. Instead of being pyrolyzed, the C(sub n)-H-O entities in the Leonid trails become vibrationally excited to higher levels n = 1, 2, 3 etc. During de-excitation they emit at 3.4 microns, due to the (0 => 1) transition, and at longer wavelengths, due to hot bands. As a first step toward verifying this hypothesis we measured the C-H vibrational manifold of hexane (C6H14). The calculated positions of the (2 => l ) , (3 => 2), and possibly (4 => 3) hot bands agree with the Leonid emission bands at 3.5, 3.8 and 4.l microns.

  18. What did Recent Leonid Meteor Storms Teach Us?

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter

    Two research aircraft operated by NASA and USAF provided an international team of 38 researchers prime viewing of two Leonid meteor storms on 19 November 2002. En route from Madrid Spain to Omaha Nebraska the storms were observed to peak at 04:06 UT and 10:47 UT respectively. A range of spectroscopic and imaging techniques were used to measure the physical properties and composition of the meteors. Highlights include the first near-IR spectra of meteors high frame-rate (1000/s) images mid-IR spectra of persistent trains and spectacular video images with a back ground of aurora. The meteoroids derive from comet 55P/Tempel-Tuttle and were ejected in 1866 and 1767 respectively only 4 and 7 orbits ago. The measured spatial and particle size distribution of dust still reflect the conditions of ejection and the influence of radiation pressures on the grains and provide unique insight into the dust-to-ice ratio in cometary matter. We will briefly review the properties of the comet's dust as it emerges from these concerted multi-spectral and imaging studies.

  19. A micrometeor component of the 1998 Leonid shower

    NASA Astrophysics Data System (ADS)

    Ma, Yuehua; He, Youwen; Williams, I. P.

    2001-08-01

    Most astronomers expected a significant meteor shower associated with the Leonid meteoroid stream to appear in 1998 and 1999. An enhanced shower was widely observed in both years, and details can be found in many published articles. In 1998, one remarkable feature was the appearance of a strong component, rich in bright meteors, which appeared about 16h before the expected maximum of the main shower, but another observed feature was an abnormal peak in the ionosphere characteristic value fbEs which was detected about 18h after the main shower. A very high value of fbEs persisted for over an hour. The likely explanation is that the ionosphere was bombarded by an additional swarm of meteoroids, much smaller than those that produce a visible trail or an ionization trail that can be picked up by radio detectors. The different dynamical behaviours between small and large meteoroids are investigated and, in consequence, an explanation for the observed phenomena is offered and 1933 is suggested as being the likely ejection time.

  20. Recognizing Leonid Meteoroids among the Collected Stratospheric Dust

    NASA Astrophysics Data System (ADS)

    Rietmeijer, Frans J. M.; Jenniskens, Peter

    Three chemical groups of primary "silicate" spheres <30 µm in diameter of cometary origin were collected in the lower stratosphere between 1981 May and 1994 July. The "silicate" sphere abundances represent an annual background from contributions by sporadic meteor and weak annual meteor shower activities. During two collection periods, from 06/22 until 08/18, 1983 (U2015), and from 09/15-12/15, 1981 (W7027/7029), a higher number of spheres was collected compared to other periods of the year represented by the other collectors studied here. This study links two different data sets, viz. the NASSA/JSC Cosmic Dust Catalogs and peak activities of annual meteor showers, and identified high-velocity cometary sources for collected stratospheric "silicate" spheres. The majority of spheres on flag U2015 may originate from comet P/Swift-Tuttle (Perseids), while the majority of spheres on flags W7027/7029 could be from comet P/Halley (Orionids) or comet P/Tempel-Tuttle (Leonids). Variations in relative proportions of the Mg,Si,Ca +/- Al, Mg,Si +/- Fe and Al, Si,Ca spheres may offer a hint of chemical differences among high-velocity comets. Proof for the findings reported here might be obtained by targeted cosmic dust collections in the lower stratosphere including periods of meteor shower and storm activity.

  1. Leonid meteor ablation, energy exchange and trail morphology

    SciTech Connect

    Zinn, John; Judd, O'Dean P.; ReVelle, D. O.

    2002-01-01

    This paper describes theoretical model studies of the interaction of Leonid meteoroids with the earth's atmosphere. Subject to some modest-to-strenuous approximations we compute the rates of ablation and deceleration, energy deposition, and terminal altitudes of the meteors as functions of their initial mass and bulk density, velocity, trajectory entry angle, drag coefficient, heat of ablation, and an ablation energy transfer fraction. We find that the dominant energy deposition in the atmosphere is associated with the stopping of the ablated meteor particles and vapor by the surrounding air. Then having computed the energy deposition rates versus altitude we compute the hydrodynamic and radiative expansion of the hot wake material in the radial direction, along with the associated air chemistry. From the computed results we can then plot two-dimensional temperature contours -- as functions of the instantaneous distance behind the meteor and radial distance from the center of the wake, at various altitudes along the meteor's path. We also compute the rates of emission of radiation and the radiative efficiency, and discuss comparisons with observations.

  2. Leonid's Particle Analyses from Stratospheric Balloon Collection on Xerogel Surfaces

    NASA Technical Reports Server (NTRS)

    Noever, David; Phillips, Tony; Horack, John; Porter, Linda; Myszka, Ed

    1999-01-01

    Recovered from a stratospheric balloon above 20 km on 17-18 November 1998, at least eight candidate microparticles were collected and analyzed from low-density silica xerogel collection plates. Capture time at Leonids' storm peak was validated locally along the balloon trajectory by direct video imaging of meteor fluence up to 24/hr above 98% of the Earth's atmosphere. At least one 30 micron particle agrees morphologically to a smooth, unmelted spherule and compares most closely in non-volatile elemental ratios (Mg/Si, Al/Si, and Fe/Si) to compositional data in surface/ocean meteorite collections. A Euclidean tree diagram based on composition makes a most probable identification as a non-porous stratospherically collected particle and a least probable identification as terrestrial matter or an ordinary chondrite. If of extraterrestrial origin, the mineralogical class would be consistent with a stony (S) type of silicate, olivine [(Mg,Fe)2SiO4] and pyroxene [(Mg, Fe)Si!O3)--or oxides, herecynite [(Fe,Mg) Al2O4].

  3. LEONID METEOROIDS: RECONCILIATION OF COMETARY OUTGASSING THEORY AND ELECTROPHONIC SOUND DATA

    SciTech Connect

    Molina, A.

    2011-05-15

    We determine the size of the largest particles that can be lifted from the nuclear surface of the comet 55P/Tempel-Tuttle using a classical outgassing model. The values obtained are in agreement with the estimated lower bound to the diameter of a Leonid meteoroid just capable of producing electrophonic sounds. Thus, we reconcile the discrepancy found by Beech between the estimated value for the maximum diameter of the particle ejected from the parent comet and the size of the 1833 Leonid meteoroid calculated as necessary to produce electrophonic sound.

  4. Successful Hybrid Approach to Visual and Video Observations of the 1999 Leonid Storm

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Crawford, Chris; Butow, Steve; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    A new hybrid technique of visual and video meteor observations is described. The method proved particularly effective for airborne observations of meteor shower activity. Results from the 1999 Leonid Multi-Instrument Aircraft Campaign are presented, and the profile shape of the 1999 Leonid storm is discussed in relation to meteor shower models. We find that the storm is best described with a Lorentz profile. Application to past meteor outbursts shows that the cui,rent multi-trailet model of a dust trail is slightly shifted and we crossed deeper into the 1899 epoch trallet than expected.

  5. Leonid Meteoroids: Reconciliation of Cometary Outgassing Theory and Electrophonic Sound Data

    NASA Astrophysics Data System (ADS)

    Molina, A.; Moreno, F.

    2011-05-01

    We determine the size of the largest particles that can be lifted from the nuclear surface of the comet 55P/Tempel-Tuttle using a classical outgassing model. The values obtained are in agreement with the estimated lower bound to the diameter of a Leonid meteoroid just capable of producing electrophonic sounds. Thus, we reconcile the discrepancy found by Beech between the estimated value for the maximum diameter of the particle ejected from the parent comet and the size of the 1833 Leonid meteoroid calculated as necessary to produce electrophonic sound.

  6. The Dynamical Evolution of A Tubular Leonid Persistent Train

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Nugent, David; Plane, John M. C.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The dynamical evolution of the persistent train of a bright Leonid meteor was examined for evidence of the source of the luminosity and the physical conditions in the meteor path. The train consisted of two parallel somewhat diffuse luminous tracks, interpreted as the walls of a tube. A general lack of wind shear along the trail allowed these structures to remain intact for nearly 200 s, from which it was possible to determine that the tubular structure expanded at a near constant 10.5 m/s, independent of altitude between 86 and 97 km. An initial fast decrease of train intensity below 90 km was followed by an increase in intensity and then a gradual decrease at longer times, whereas at high attitudes the integrated intensity was nearly constant with time. These results are compared to a model that describes the dynamical evolution of the train by diffusion, following an initial rapid expansion of the hot gaseous trail behind the meteoroid. The train luminosity is produced by O ((sup 1)S) emission at 557 nm, driven by elevated atomic O levels produced by the meteor impact, as well as chemiluminescent reactions of the ablated metals Na and Fe with O3. Ozone is rapidly removed within the train, both by thermal decomposition and catalytic destruction by the metallic species. Hence, the brightest emission occurs at the edge of the train between outwardly diffusing metallic species and inwardly diffusing O3. Although the model is able to account plausibly for a number of characteristic features of the train evolution, significant discrepancies remain that cannot easily be resolved.

  7. The Dynamical Evolution of a Tubular Leonid Persistent Train

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter; Nugent, David; Plane, John M. C.

    The dynamical evolution of the persistent train of a bright Leonid meteor was examined for evidence of the source of the luminosity and the physical conditions in the meteor path. The train consisted of two parallel somewhat diffuse luminous tracks, interpreted as the walls of a tube. A general lack of wind shear along the trail allowed these structures to remain intact for nearly 200 s, from which it was possible to determine that the tubular structure expanded at a near constant 10.5 ms^-1, independent of altitude between 86 and 97 km. An initial fast decrease of train intensity below 90 km was followed by an increase in intensity and then a gradual decrease at longer times, whereas at high altitudes the integrated intensity was nearly constant with time. These results are compared to a model that describes the dynamical evolution of the train by diffusion, following an initial rapid expansion of the hot gaseous trail behind the meteoroid. The train luminosity is produced by O (^1S) emission at 557 nm, driven by elevated atomic O levels produced by the meteor impact, as well as chemiluminescent reactions of the ablated metals Na and Fe with O_3. Ozone is rapidly removed within the train, both by thermal decomposition and catalytic destruction by the metallic species. Hence, the brightest emission occurs at the edge of the train between outwardly diffusing metallic species and inwardly diffusing O_3. Although the model is able to account plausibly for a number of characteristic features of the train evolution, significant discrepancies remain that cannot casily be resolved.

  8. Observations of the Leonid Meteoroid Stream by a Multistation FS Radio System

    NASA Astrophysics Data System (ADS)

    Cevolani, Giordano; Pupillo, Giuseppe; Hajduk, Anton; Porubčan, Vladimir

    Results of joint campaigns of the Leonid meteoroid stream performed throughout the 1995-1999 years by the BLM (Bologna-Lecce-Modra) forward scatter (FS) radar, are shown and compared with visual observations. In 1998 and 1999 at both the stations of Lecce and Modra, the total reflection time is shown to give a better indication of the Leonid activity. For the two years the trends of the reflection time and of the overdense echoes (T > 8 sec duration) exhibit multiple peaks just at the maximum of the shower activity. In 1999, strong evidence of a short and extremely intense activity at the nodal longitude of the parent comet (November 18, 02h UT), is deduced from the radio data. The Leonid display is shown to follow a Gaussian activity profile and the particle density/stream width relationship is found to match observations of IRAS dust trails of comparable short-period comets. The mass distribution exponent shows a representation of an extended component of larger particles (brighter Leonids) in 1996 and especially in 1998. Average mass and population indices of radio and visual data show a similar trend in the 1995-1999 period.

  9. Large Leonid entry modeling : application to the bolide of 11/17/1998

    SciTech Connect

    ReVelle, D. O.

    2001-01-01

    In this paper we apply the theoretical entry model of ReVelle (2001c) to the large Leonid bolide of November 17, 1998. We modeled the entry both using hypersonic aerodynamics and compared the results to the infrasonic detection and interpretation of the event by ReVelle and Whitaker (1999).

  10. Low-Density Silica Xerogel Capture of Leonids Meteor Storm Dust Candidates by Stratospheric Balloon Return

    NASA Technical Reports Server (NTRS)

    Noever, David; Phillips, Tony; Horack, John; Myszka, Ed; Porter, Linda; Jerman, Greg

    1999-01-01

    High altitude balloon (20 km) and low-density capture media were explored to return meteor-related dust during the November 1998 Leonids meteor storm. One 20-30 micron particle captured showed a characteristic signature of extraterrestrial origin, featuring high aluminum, magnesium and other non-volatile metals. The technique of balloon capture will be optimized for March and November 1999 reflights.

  11. An ET Origin for Stratospheric Particles Collected during the 1998 Leonids Meteor Shower

    NASA Technical Reports Server (NTRS)

    Noever, David A.; Phillips, James A.; Horack, John M.; Jerman, Gregory; Myszka, Ed

    1999-01-01

    On 17 November 1998, a helium-filled weather balloon was launched into tfle strato- sphere, equipped with a xerogel microparticle collector. The three-hour flight was designed to sample the dust environment in the stratosphere during the Leonid meteor shower, and possibly to capture Leonid meteoroids. Environmental Scanning Election Microscope analyses of the returned collectors revealed the capture of a -30-pm particle. with a smooth, multigranular shape, and partially melted, translucent rims; similar to known Antarctic micrometeorites. Energy-dispersive X-ray Mass Spectroscopy shows en- riched concentrations of the non-volatile elements, Mg, Al, and Fe. The particle possesses a high magnesium to iron ratio of 2.96, similar to that observed in 1998 Leonids meteors (Borovicka, et al. 1999) and sharply higher than the ratio expected for typical material from the earth's crust. A statistical nearest-neighbor analysis of the abundance ratios Mg/Si, Al/Si, and Fe/Si demonstrates that the particle is most similar in composition to cosmic spherules captured during airplane flights throucrh the stratosphere. The mineralogical class is consistent with a stony (S) type of silicates. olivine [(Mg, Fe)2SiO4] and pyroxene [(Mg,Fe)SiO3]-or oxides, herecynite [(Fe,Mg) Al2O4]. Attribution to the debris stream of the Leonids' parent body, comet Tempel-Tuttle, would make it the first such material from beyond the orbit of Uranus positively identified on Earth.

  12. Modeling an enhancement of the lunar sodium tail during the Leonid Meteor Shower of 1998

    NASA Astrophysics Data System (ADS)

    Wilson, Jody K.; Smith, Steven M.; Baumgardner, Jeffrey; Mendillo, Michael

    A region of non-terrestrial sodium emission seen in the sky on the nights of November 18-20, 1998, has been interpreted as the Moon's distant sodium tail, possibly enhanced by micrometeor impact vaporization of the lunar regolith by the Leonid meteor shower. We show that the location and morphology of the spot can be explained by standard steady-state models of the Moon's sodium atmosphere. Moreover, using a new time-dependent simulation of the lunar atmosphere, we find that the Na escape rate from the Moon increased to 2 or 3 times its normal level during the most intense period of the 1998 Leonid meteor shower on November 16th and 17th.

  13. A Study Of Leonid Impact Flashes On The Moon In 2004

    NASA Astrophysics Data System (ADS)

    Ortiz, J. L.; Aceituno, F. J.; Santos-Sanz, P.; Quesada, J. A.

    2005-08-01

    In November 2004 the lunar phase was adequate to observe lunar impact flashes at the time of the Leonid meteor shower, as it was the case in 1999 and 2001, because a large number of meteoroidal impacts were expected to hit the night part of the Moon visible from Earth. We again arranged a special multisite observing campaign with telescopes aiming at the night part of the Moon in order to detect and analyze such flashes. In this paper we report our unambiguous detections, our computations of the energy released in each impact, their locations on the Moon and possible inferences on crater sizes. Those fresh craters might perhaps be observable from SMART-1. Some implications on Leonid meteor fluxes on Earth and size distribution of the particles are also discussed. This research was supported by the spanish AYA-2002-0382 project. FEDER funds are also acknowledged.

  14. Interplanetary Dust Particles of Micron Size Probably Associated with the Leonid Meteor Stream

    NASA Technical Reports Server (NTRS)

    Alexander, W. M.; McCracken, C. W.; LaGow, H. E.

    1961-01-01

    An interplanetary dust particle event, coincident with the Leonid meteor shower and lasting approximately 70 hours, was recorded by a sensor on the Vanguard III satellite. During this interval the satellite's microphone system registered impacts of approximately 2800 dust particles with momenta exceeding 10(exp -2) dyne-second. The impact rate varied by as much as two orders of magnitude within a few hours. The microphone system was almost omnidirectional, so the radiants of the dust particles cannot be defined. Association of these dust particles with the Leonid meteor stream is suggested by the coincidence in time and by the location of the satellite. Vanguard III traversed five major meteor streams, but the impact rates significantly exceeded the background rate only during this one interval. This is the first case in which a significant increase in the directly measured impact rate of dust particles possibly can be associated with a major meteor stream.

  15. The 1999 Leonid Multi-Instrument Aircraft Campaign - An Early Review

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter; Butow, Steven J.; Fonda, Mark

    Two B707-type research aircraft of the 452^nd Flight Test Squadron at Edwards Air Force Base were deployed to study the Leonid meteor storm of 1999 over the Mediterranean Sea on Nov. 18. The mission was sponsored by various science programs of NASA, and offered an international team of 35 researchers observing conditions free of clouds and low altitude extinction at a prime location for viewing the storm. This 1999 Leonid Multi-Instrument Aircraft Campaign followed a similar effort in 1998, improving upon mission strategy and scope. As before, spectroscopic and imaging experiments targeted meteors and persistent trains, but also airglow, aurora, elves and sprites. The research aimed to address outstanding questions in astrobiology, planetary science, astronomy, and upper atmospheric research. In addition, USAF co-sponsored the mission to provide near real-time flux measurements for space weather awareness. First results are presented in these issues of Earth, Moon, and Planets in preparation for future missions that will target the exceptional Leonid returns of 2001 and 2002. An early review of the scientific achievements in the context of campaign objectives is given.

  16. Characteristics of Fe Ablation Trials Observed During the 1998 Leonid Meteor Shower

    NASA Technical Reports Server (NTRS)

    Chu, Xin-Zhao; Pan, Wei-Lin; Papen, George; Swenson, Gary; Gardner, Chester S.; Jenniskens, Peter; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Eighteen Fe ablation trails were observed during the 17/18 Nov 1998 Leonid meteor shower with an airborne Fe lidar aboard the National Simulation Facility/National Center for Atmospheric Research (NSF/NCAR) Electra aircraft over Okinawa. The average altitude of the 18 trails from the high velocity (72 km/s) Leonid meteors, 95.67 +/- 0.93 km, is approximately 6.7 km higher than previously observed for slower (approx. 30 km/s) sporadic meteors. This height difference is consistent with the assumption that meteors ablate when the kinetic energy imparted to the atmosphere reaches a critical threshold. The average age of the Fe trails, determined by a diffusion model, is 10.1 min. The youngest ages were observed below 92 km and above 98 km where chemistry and diffusion dominate, respectively. The average abundance of the trails is ten percent of the abundance of the background Fe layer. Observations suggest that the 1998 Leonid shower did not have a significant impact on the abundance of the background Fe layer.

  17. [Discovering a masterpiece--the Russian physician and author Leonid Tsypkin (1926-82)].

    PubMed

    Skårderud, Finn

    2008-11-01

    The paper presents a literary work unknown to most readers. The Russian author Leonid Tsypkin (1926 - 82) is among those who were discovered and even declared literary geniuses after their dead. He never saw a line of his own fiction published. Tsypkin studied medicine in Minsk in Belarus and later practiced as a pathologist in Moscow where he obtained two PhDs and authored numerous scientific publications. In his novel "Summer in Baden-Baden", the Jew Tsypkin declares his love to the anti-Semitic author Fjodor Dostojevskij. Tsypkins' own life became more and more complicated due to anti-Semitism in the Soviet Union. PMID:19096477

  18. Leonid Vital'evich Kantorovich (on the 100th anniversary of his birth)

    NASA Astrophysics Data System (ADS)

    Vershik, Anatolii M.; Kutateladze, Semen S.; Novikov, Sergei P.

    2012-06-01

    The 19th of January 2012 was the 100th anniversary of the birth of Leonid Vital'evich Kantorovich, an outstanding mathematician and economist of international fame. A child prodigy, who graduated from the university at 18 and became a professor at 20, an academician in the mathematical sciences and a laureate of the Nobel Prize in economics, - these are extraordinary circumstances of his life. They are remarkable in themselves, but also the results he achieved were exceptional and immensely impressive, and the younger generations of researchers, first and foremost mathematicians and economists, must know about them.

  19. Origin and evolution of recent Leonid meteor showers. [perturbed motion of meteor stream

    NASA Technical Reports Server (NTRS)

    Mcintosh, B. A.

    1973-01-01

    The four most prominent returns of the Leonid shower in the past decade fall into two broad classes. The 1966 and 1969 showers were of short duration, had a high proportion of small particles, and occured with the longest apparent delay after the perihelion passage of the parent comet Temple-Tuttle. By contrast, the 1961 and 1965 returns were of long duration, and had more large particles. The 1961 return preceded the comet. There are three major influences on particle orbits: ejection velocity, radiation pressure, and close encounters with planets. The observations are explainable in a qualitative way on the basis of the first two. But some speculation concerning the results of planetary perturbations are invoked.

  20. Leonid Shower Probe of Aerothermochemistry in Meteoric Plasmas and Implication for the Origin of Life

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter S. I.; Packan, D.; Laux, C.; Wilson, Mike; Boyd, I. D.; Kruger, C. H.; Popova, O.; Fonda, M.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The rarefied and high Mach number (up to 270) of the flow field of a typical meteoroid as it enters the Earth's atmosphere implies conditions of ablation and atmospheric chemistry that have proven to be as difficult to grasp as the proverbial shooting star. An airborne campaign was organized to study these processes during an intense Leonid shower. A probe of molecular band emission now demonstrates that the flash of light from a common meteor originates in the wake of the object rather than in the meteor head. A new theoretical approach using the direct simulation Monte Carlo technique demonstrates that the ablation process is critical in heating the air in that wake. Air molecules impinge on a dense cloud of ablated material in front of the meteoroid head into an extended wake that has the observed excitation temperatures. These processes determine what extraterrestrial materials may have been delivered to Earth at the time of the origin of life.

  1. Precise Trajectories and Orbits of Meteoroids from the 1999 Leonid Meteor Storm

    NASA Technical Reports Server (NTRS)

    Betlem, Hans; Jenniskens, Peter; Spurny, Pavel; VanLeeuwen, Guus Docters; Miskotte, Koen; TerKuile, Casper R.; Zerubin, Peter; Angelos, Chris; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Photographic multi-station observations of 47 Leonid meteors are presented that were obtained from two ground locations in Spain during the 1999 meteor storm. We find an unresolved compact cluster of radiants at alpha = 153.67 +/- 0.05 and delta = 21.70 +/- 0.05 for a mean solar longitude of 235.282 (J2000). The position is identical to that of the November 17/18 outburst of 1998, which implies that both are due to comet 55P/Tempel-Tuttle's ejecta from 1899. We also find a halo which contains about 28% of all meteors. The spatial distribution of radiant positions appears to be Lorentzian, with a similar fraction of meteors in the profile wings as the meteor storm activity curve.

  2. The 1999 Leonid Multi-Instrument Aircraft Campaign - An Early Review

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Butow, Steven J.; Fonda, Mark; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The Leonid meteor storm of 1999 was observed from two B707-type research aircraft by a team of 35 scientists of seven nationalities over the Mediterranean Sea on Nov. 18, 1999. The mission was sponsored by various science programs of NASA, and offered the best possible observing conditions, free of clouds and at a prime location for viewing the storm. The 1999 mission followed a similar effort in 1998, improving upon mission strategy and scope. As before, spectroscopic and imaging experiments targeted meteors and persistent trains, but also airglow, aurora, elves and sprites. The research aimed to address outstanding questions in Planetary Science, Astronomy, Astrobiology and upper atmospheric research, including Aeronornie. In addition, near real-time flux measurements contributed to a USAF sponsored program for space weather awareness. An overview of the first results is given, which are discussed in preparation for future missions.

  3. Video Observations Encompassing the 2002 Leonid Storm: First Results and a Revised Photometric Procedure for Video Meteor Analysis

    NASA Technical Reports Server (NTRS)

    Cooke, William J.; Suggs, Robert M.; Swift, Wesley; Gural, Peter S.; Brown, Peter; Parker, Nelson C. (Technical Monitor)

    2002-01-01

    During the 2001 Leonid storm, Marshall Space Flight Center, with the cooperation of the University of Western Ontario and the United States Air Force, deployed 6 teams of observers equipped with intensified video systems to sites located in North America, the Pacific, and Mongolia. The campaign was extremely successful, with the entire period of enhanced Leonid activity (over 16 hours) captured on video tape in a consistent manner. We present the first results from the analysis of this unique, 2 terabyte data set and discuss the problems involved in reducing large amounts of video meteor data. In particular, the question of how to determine meteor masses though photometric analysis will be re-examined, and new techniques will be proposed that eliminate some of the deficiencies suffered by the techniques currently employed in video meteor analysis.

  4. Enhancement of the Moon's Sodium Tail Following the Leonid Meteor Shower of 1998.

    NASA Astrophysics Data System (ADS)

    Wilson, J. K.; Smith, S. M.; Baumgardner, J.; Mendillo, M.

    1999-09-01

    We have made the first detections of the distant lunar sodium tail with an all-sky camera on the nights of August 21-22 and November 18-20, 1998. The lunar sodium tail represents the escaping component of the lunar sodium atmosphere, which is generated from the Moon's regolith by a combination of surface processes. On nights near new Moon, the sodium tail appears in the sky as a spot near the anti-solar point; the location and morphology of this spot are consistent with standard models of the Moon's atmosphere. We interpret the changing brightness of the spot from night to night using a new time-dependent model of the lunar atmosphere, and we find that the atomic sodium escape rate from the Moon temporarily increased by a factor of 2 to 3 during the most intense period of the 1998 Leonid meteor shower on November 16 and 17. This is the most significant meteor-related atmospheric enhancement yet observed, and it may help to quantify the contribution of micrometeor bombardment to the lunar atmosphere.

  5. Search for Extraterrestrial Origin of Atmospheric Trace Molecules Radio Sub-MM Observations During The Leonids

    NASA Technical Reports Server (NTRS)

    Depois, D.; Ricaud, P.; Lautie, N.; Schneider, N.; Jacq, T.; Biver, N.; Lis, D.; Chamberlain, R.; Phillips, T.; Miller, M.; Jenniskens, P.

    2000-01-01

    HCN is a minor constituent of the Earth atmosphere, with a typical volume mixing ratio around 10(exp -10) HCN per air molecule. At present, the main source of HCN in the lower atmosphere is expected to be biomass burning. The atmospheric HCN has been observed since 1981, first in the infrared, then at microwave radio frequencies. Globally, above 30 km, HCN measurements are in excess of model predictions based on standard photochemistry and biomass burning as the only HCN source. This excess has been explained by: 1) ion-catalyzed reactions in the entire stratosphere, involving CH.3CN as a precursor and/or 2) a high altitude source as a result of chemical production from the methyl radical CH3, or from injection or production by meteors. HCN is a minor constituent of cometary ices. HCN polymers or copolymers have been suggested as constituents of cometary refractory organic matter, and would thus be present in the incoming meteoroids, if these polymers survived their stay in interplanetary space after ejection. HCN may also be created from the CN radical decomposition product of organic carbon, after reaction with hydrogen-bearing molecules. To test the hypothesis of HCN input by meteoroids or the formation in the upper atmosphere from meteoric ablation products, we decided to monitor the HCN submillimeter lines around a major shower: the Leonids.

  6. MSFC Stream Model Preliminary Results: Modeling Recent Leonid and Perseid Encounters

    NASA Technical Reports Server (NTRS)

    Cooke, William J.; Moser, Danielle E.

    2004-01-01

    The cometary meteoroid ejection model of Jones and Brown (1996b) was used to simulate ejection from comets 55P/Tempel-Tuttle during the last 12 revolutions, and the last 9 apparitions of 109P/Swift-Tuttle. Using cometary ephemerides generated by the Jet Propulsion Laboratory s (JPL) HORIZONS Solar System Data and Ephemeris Computation Service, two independent ejection schemes were simulated. In the first case, ejection was simulated in 1 hour time steps along the comet s orbit while it was within 2.5 AU of the Sun. In the second case, ejection was simulated to occur at the hour the comet reached perihelion. A 4th order variable step-size Runge-Kutta integrator was then used to integrate meteoroid position and velocity forward in time, accounting for the effects of radiation pressure, Poynting-Robertson drag, and the gravitational forces of the planets, which were computed using JPL s DE406 planetary ephemerides. An impact parameter was computed for each particle approaching the Earth to create a flux profile, and the results compared to observations of the 1998 and 1999 Leonid showers, and the 1993 and 2004 Perseids.

  7. STS-87 Payload Specialist Leonid Kadenyuk chats with NASA Administrator Daniel Goldin shortly after

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine (NSAU), at left, chats with NASA Administrator Daniel Goldin shortly after the landing of Columbia at Kennedy Space Center. Looking on is back-up Payload Specialist Yaroslav Pustovyi, also of NSAU. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, at KSC's Shuttle Landing Facility Runway 33, drawing the 15-day, 16-hour and 34- minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Commander Kevin Kregel; Pilot Steven Lindsey; and Mission Specialists Winston Scott, Kalpana Chawla, Ph.D., and Takao Doi, Ph.D., of the National Space Development Agency of Japan. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  8. STS-87 P.S. Leonid Kadenyuk of NSAU and Daniel Goldin after landing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine (NSAU), at left, greets NASA Administrator Daniel Goldin, at right, as back-up Payload Specialist Yaroslav Pustovyi, also of NSAU, looks on. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, at KSC's Shuttle Landing Facility Runway 33, drawing the 15-day, 16-hour and 34-minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Commander Kevin Kregel; Pilot Steven Lindsey; and Mission Specialists Winston Scott; Kalpana Chawla, Ph.D.; and Takao Doi, Ph.D. of the National Space Development Agency of Japan. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  9. Lorentz Shaped Comet Dust Trail Cross Section from New Hybrid Visual and Video Meteor Counting Technique - Implications for Future Leonid Storm Encounters

    NASA Astrophysics Data System (ADS)

    Jenniskens, Peter; Crawford, Chris; Butow, Steven J.; Nugent, David; Koop, Mike; Holman, David; Houston, Jane; Jobse, Klaas; Kronk, Gary; Beatty, Kelly

    A new hybrid technique of visual and video meteor observations was developed to provide high precision near real-time flux measurements for satellite operators from airborne platforms. A total of 33,000 Leonids, recorded on video during the 1999 Leonid storm, were watched by a team of visual observers using a video head display and an automatic counting tool. The counts reveal that the activity profile of the Leonid storm is a Lorentz profile. By assuming a radial profile for the dust trail that is also a Lorentzian, we make predictions for future encounters. If that assumption is correct, we passed 0.0003 AU deeper into the 1899 trailet than expected during the storm of 1999 and future encounters with the 1866 trailet will be less intense than predicted elsewhere.

  10. Lorentz-Shaped Comet Dust Trail Cross Section from New Hybrid Visual and Video Meteor Counting Technique - Implications for Future Leonid Storm Encounters

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Crawford, Chris; Butow, Steven J.; Nugent, David; Koop, Mike; Holman, David; Houston, Jane; Jobse, Klaas; Kronk, Gary

    2000-01-01

    A new hybrid technique of visual and video meteor observations was developed to provide high precision near real-time flux measurements for satellite operators from airborne platforms. A total of 33,000 Leonids. recorded on video during the 1999 Leonid storm, were watched by a team of visual observers using a video head display and an automatic counting tool. The counts reveal that the activity profile of the Leonid storm is a Lorentz profile. By assuming a radial profile for the dust trail that is also a Lorentzian, we make predictions for future encounters. If that assumption is correct, we passed 0.0003 AU deeper into the 1899 trailet than expected during the storm of 1999 and future encounters with the 1866 trailet will be less intense than. predicted elsewhere.

  11. Buoyancy of the ''Y2K'' Persistent Train and the Trajectory of the 04:00:29 UT Leonid Fireball

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Rairden, Rick L.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The atmospheric trajectory is calculated of a particularly well studied fireball and train during the 1999 Leonid Multi-Instrument Aircraft Campaign. Less than a minute after the meteor's first appearance, the train curves into a '2'-shape, which persisted until at least 13 minutes after the fireball. We conclude that the shape results because of horizontal winds from gravity waves with a scale height of 8.3 km at 79-91 km altitude, as well as a westerly wind gradient with altitude. In addition, there is downward drift that affects the formation of loops in the train early on.

  12. Investigation of the Ejection and Physical Properties of Large Comet Dust Grains and Their Interaction with Earth's Atmosphere During the 2002 Leonid Multi-Instrument Aircraft Campaign

    NASA Astrophysics Data System (ADS)

    Jenniskens, P.; Russell, R. W.; Yano, H.; Plane, J. M. C.; Murray, I. S.; Taylor, M. J.; Borovicka, J.; Kuenzi, K.; Smith, W. H.; Rairden, R. L.; Stenbaek-Nielsen, H. C.; Rietmeijer, F. J. M.; Betlem, H.; Martinez-Frias, J.

    2003-05-01

    In November 2002, the Leonid Multi-Instrument Aircraft Campaign had its final mission to explore the Leonid meteor storms for what they can tell us about comets, meteors, and how they may have contributed prebiotic compounds to the origin of life. The mission provided an airborne platform to 36 researchers of seven countries. The storms were caused by Earth's crossing of the 1767 and 1866 dust ejecta of comet 55P/Tempel-Tuttle. The Center for Astrobiology (CAB) hosted the mission at Torrejon AB in Spain. In a westward flight back to Omaha, Nebraska, the aircraft encountered the first storm at 04:06 UT on Nov. 19, with rates of ZHR 2,300 /hr, and the second peak at 10:47 UT, when rates increased again to ZHR 2,600 /hr. The wealth of faint meteors made the showers difficult to observe from the ground. The narrow and slightly asymmetric flux profiles add to a three-dimensional map of the dust density in 55P/Tempel-Tuttle's one-revolution dust trail. Meteoroid composition and morphology were measured for numerous individual particles. The first near-IR spectra of meteors were recorded. High frame-rate imaging confirmed the formation of a shock-like feature in bright Leonids, adding to a new understanding of the physical conditions in the rarefied flow of meteors. The interaction of meteors with the atmosphere was investigated at optical and sub-mm wavelengths. Optical and mid-IR emissions of persistent trains were recorded. We will briefly review these first results and their implication for comet dust ejection and evolution in the interplanetary and Earth environment. The 2002 Leonid MAC mission was supported by NASA's Astrobiology and Planetary Astronomy programs, by ESA, and by CAB. NASA's DC-8 Airborne Laboratory was operated by NASA DFRC and the NKC-135 "FISTA" aircraft by Edwards AFB. Leonid MAC was organized by the SETI Institute and NASA Ames Research Center.

  13. MSFC Stream Model Preliminary Results: Modeling the 1998-2002 Leonid Encounters and the 1993,1994, and 2004 Perseid Encounters

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Cooke, W. J.

    2004-01-01

    The cometary meteoroid ejection models of Jones (1996) and Crifo (1997) were used to simulate ejection from comets 55P/Tempel-Tuttle during the last 12 revolutions, and the 1862, 1737, and 161 0 apparitions of 1 OSP/Swift-Tuttle. Using cometary ephemerides generated by the JPL HORIZONS Solar System Data and Ephemeris Computation Service, ejection was simulated in 1 hour time steps while the comet was within 2.5 AU of the Sun. Also simulated was ejection occurring at the hour of perihelion passage. An RK4 variable step integrator was then used to integrate meteoroid position and velocity forward in time, accounting for the effects of radiation pressure, Poynting-Robertson drag, and the gravitational forces of the planets, which were computed using JPL's DE406 planetary ephemerides. An impact parameter is computed for each particle approaching the Earth, and the results are compared to observations of the 1998-2002 Leonid showers, and the 1993-1 994 Perseids. A prediction for Earth's encounter with the Perseid stream in 2004 is also presented.

  14. Characterization of Leonid meteor head echo data collected using the VHF-UHF Advanced Research Projects Agency Long-Range Tracking and Instrumentation Radar (ALTAIR)

    NASA Astrophysics Data System (ADS)

    Close, S.; Hunt, S. M.; McKeen, F. M.; Minardi, M. J.

    2002-02-01

    The Leonid meteor shower, which was predicted to hit storm-like activity on 17 November 1998, was observed using radar and optical sensors at the Kwajalein Missile Range in order to study potential threats to orbiting spacecraft. Meteor head echo data were collected during the predicted peak of the ``storm'' primarily using the Advanced Research Projects Agency Long-Range Tracking and Instrumentation Radar (ALTAIR). ALTAIR is a dual-frequency radar at VHF (160 MHz) and UHF (422 MHz) that is uniquely suited for detecting meteor head echoes due to high sensitivity, precise calibration, and the ability to record radar data at a high rate (Gb/min). ALTAIR transmits right-circular (RC) polarized energy and records left-circular (LC) sum, RC sum, LC azimuth angle difference, and LC elevation angle difference channels; these four measurements facilitate the determination of three-dimensional target position and velocity as a function of radar cross section and time. During the predicted peak of the storm, ALTAIR detected 734 VHF head echoes in 29 min of data and 472 UHF head echoes in 17 min of data, as well as numerous specular and nonspecular ionization trails. This paper contains analysis on the head echo data, including dual-frequency statistics and the variability of head echo decelerations. We also include results from the analysis of the radius-density parameter, which shows a strong correlation with deceleration.

  15. Meteor radar wind over Chung-Li (24.9°N, 121°E), Taiwan, for the period 10-25 November 2012 which includes Leonid meteor shower: Comparison with empirical model and satellite measurements

    NASA Astrophysics Data System (ADS)

    Su, C. L.; Chen, H. C.; Chu, Y. H.; Chung, M. Z.; Kuong, R. M.; Lin, T. H.; Tzeng, K. J.; Wang, C. Y.; Wu, K. H.; Yang, K. F.

    2014-08-01

    The neutral winds in the mesosphere and lower thermosphere (MLT) region are measured by a newly installed meteor trail detection system (or meteor radar) at Chung-Li, Taiwan, for the period 10-25 November 2012, which includes the Leonid meteor shower period. In this study, we use the 3 m field-aligned plasma irregularities in the sporadic E (Es) region in combination with the International Geomagnetic Reference Field model to calibrate the system phase biases such that the true positions of the meteor trails can be correctly determined with interferometry technique. The horizontal wind velocities estimated from the radial velocities of the meteor trails and their locations by using a least squares method show that the diurnal tide dominates the variation of the MLT neutral wind with time over Chung-Li, which is in good agreement with the horizontal wind model (HWM07) prediction. However, harmonic analysis reveals that the amplitudes of the mean wind, diurnal, and semidiurnal tides of the radar-measured winds in height range 82-100 km are systematically larger than those of the model-predicted winds by up to a factor of 3. A comparison shows that the overall pattern of the height-local time distribution of the composite radar-measured meteor wind is, in general, consistent with that of the TIMED Doppler Interferometer-observed wind, which is dominated by a diurnal oscillation with downward phase progression at a rate of about 1.3 km/h. The occurrences of the Es layers retrieved from fluctuations of the amplitude and excess phase of the GPS signal received by the FORMOSAT-3/COSMIC satellites during the GPS radio occultation (RO) process are compared with the shear zones of the radar-measured meteor wind and HWM07 wind. The result shows that almost all of the RO-retrieved Es layers occur within the wind shear zones that favor the Es layer formation based on the wind shear theory, suggesting that the primary physical process responsible for the Es layer events

  16. Mission goals of a 1998/1999 Leonid storm Multi-instrument Aircraft Campaign (MAC)

    NASA Technical Reports Server (NTRS)

    Jenniskens, P.; Butow, S.

    1998-01-01

    In November of 1998 (or in 1999 with about equal probability) will be our one chance in a lifetime to anticipate with some certainty the occurrence of a meteor storm. For a period of up to 2 hours, rates are expected to increase above 1 meteor per second for a naked eye observer. At that time, Earth passes through the outer regimes of the dust trail of comet 55P/Tempel-Tuttle. The high meteor flux offers unprecedented precision in characterizing the dust trail in terms of spatial and particle size distributions of dust grains and allows the measurement of composition, morphology and orbits of individual cometary grains relatively soon after ejection from the comet. By using the Earth's atmosphere as a detector for the dust trains, grains are sampled over a wide mass range, from the typical grain size of zodiacal dust (40 - 200 micron) up until the rare boulders that can still be lifted off the comet nucleus.

  17. FROM THE HISTORY OF PHYSICS: The forefather (about Leonid Isaakovich Mandelstam)

    NASA Astrophysics Data System (ADS)

    Feinberg, Evgenii L.

    2002-01-01

    An essay and some private reminiscences on the life, work, public activities, and the personality of the prominent scientist who established the Moscow school of theoretical physics in the second quarter of the 20th century.

  18. Dust Acoustic Mode Manifestations in Earth's Dusty Ionosphere

    SciTech Connect

    Kopnin, S.I.; Popel, S.I.

    2005-10-31

    Dust acoustic mode manifestations in the dusty ionosphere are studied. The reason for an appearance of the low-frequency radio noises associated with such meteor fluxes as Perseids, Orionids, Leonids, and Gemenids is determined.

  19. 73X Faster Than a Speeding Bullet

    NASA Video Gallery

    On Nov. 17, 2011, a NASA camera in Tullahoma, Tenn., saw a Leonid meteor -- moving 73 times faster than a bullet fired from an M-16 rifle -- as it burned up 71 miles above Nolensville, Tenn., at an...

  20. Constraining the Physical Properties of Meteor Stream Particles by Light Curve Shapes Using the Virtual Meteor Observatory

    NASA Technical Reports Server (NTRS)

    Koschny, D.; Gritsevich, M.; Barentsen, G.

    2011-01-01

    Different authors have produced models for the physical properties of meteoroids based on the shape of a meteor's light curve, typically from short observing campaigns. We here analyze the height profiles and light curves of approx.200 double-station meteors from the Leonids and Perseids using data from the Virtual Meteor Observatory, to demonstrate that with this web-based meteor database it is possible to analyze very large datasets from different authors in a consistent way. We compute the average heights for begin point, maximum luminosity, and end heights for Perseids and Leonids. We also compute the skew of the light curve, usually called the F-parameter. The results compare well with other author's data. We display the average light curve in a novel way to assess the light curve shape in addition to using the F-parameter. While the Perseids show a peaked light curve, the average Leonid light curve has a more flat peak. This indicates that the particle distribution of Leonid meteors can be described by a Gaussian distribution; the Perseids can be described with a power law. The skew for Leonids is smaller than for Perseids, indicating that the Leonids are more fragile than the Perseids.

  1. Meteoric activities during the 11th century

    NASA Astrophysics Data System (ADS)

    Ahn, Sang-Hyeon

    2005-04-01

    We have analysed the meteor records in the chronicles that describe the era of the Song dynasty (AD 960-1279). The data are complementary to the record-vacant 10th century of the Koryo dynasty (AD 918-1392). The annual activity of sporadic meteors analysed shows a generic sinusoidal behaviour as in modern observations. In addition, we have also found that there are two prominent meteor showers, one in August and the other in November, appearing on the fluctuating sporadic meteors. The date of occurrence of the August shower indicates it to be the Perseids. By comparing the date of occurrence of the November shower with those of the Leonid showers of the Koryo dynasty, recent visual observations and the world-wide historical meteor storms, we conclude that the November shower is the Leonids. The regression rate of the Leonids is obtained to be days per century, which agrees with recent observations.

  2. PF191012 Myszyniec - highest Orionid meteor ever recorded

    NASA Astrophysics Data System (ADS)

    Olech, A.; Żołaḑek, P.; Wiśniewski, M.; Fietkiewicz, K.; Maciejewski, M.; Tymiński, Z.; Krzyżanowski, T.; Krasnowski, M.; Kwinta, M.; Myszkiewicz, M.; Polakowski, K.; Zarȩba, P.

    2013-09-01

    On the night of Oct. 18/19, 2012, at 00:23 UT, a -14.7 mag Orionid fireball occurred over northeastern Poland. The precise orbit and atmospheric trajectory of the event are presented, based on the data collected by five video stations and one photographic Polish Fireball Network station. The beginning height of the meteor is 168.4 ± 0.6 km, which makes the PF191012 Myszyniec fireball the highest ever observed, well-documented meteor not belonging to the Leonid shower. The ablation became the dominant source of light of the meteor at a height of around 115 km. The thermalization of sputtered particles is suggested to be the source of radiation above that value. The transition height of 115 km is 10-15 km below the transition heights derived for Leonids and might suggest that the material of Leonids is more fragile and probably has smaller bulk density than that of Orionids.

  3. Meteoroids and Meteor Storms: A Threat to Spacecraft

    NASA Technical Reports Server (NTRS)

    Anderson, B. Jeffrey

    1999-01-01

    Robust system design is the best protection against meteoroid damage. Impacts by small meteoroids are common on satellite surfaces, but impacts by meteoroids large enough to damage well designed systems are very rare. Estimating the threat from the normal meteoroid environment is difficult. Estimates for the occasional "storm" are even more uncertain. Common sense precautions are in order for the 1999 Leonids, but wide-spread catastrophic damage is highly unlikely. Strong Leonid showers are also expected in 2000 and 2001, but these pose much less threat than 1999.

  4. From Brezhnev Doctrine to New Thinking: Soviet Reforms and European Security.

    ERIC Educational Resources Information Center

    Lukaszewski, Witold J.

    Mikhail Gorbachev has drastically altered the foreign policy of the Soviet Union, and in so doing has also brought about a new international political reality for all of Europe. This paper contrasts Gorbachev's "New Thinking" in foreign policy with the Brezhnev Doctrine (an approach associated with former USSR leader Leonid Brezhnev that…

  5. Perspectivas Pedagogicas. Documentos-Ponencias Y Ensayos Proyecto Teacher Corps, Ciclo XII (Pedagogical Perspectives. Documents, Papers and Essays, Teacher Corps Project, Cycle XII).

    ERIC Educational Resources Information Center

    Albino, Isidra, Ed.; Davila, Sonia, Ed.

    The purpose of this book is to stimulate ideas leading to a sharing of approaches, strategies, and methodologies applicable to the education of Puerto Ricans. Following introductory material, 18 papers are presented, the first 10 of which are in Spanish. Titles and authors are: (1) "El maestro que Puerto Rico necesita," Leonides Santos Vargas; (2)…

  6. The First Confirmed Videorecordings of Lunar Meteor Impacts

    NASA Technical Reports Server (NTRS)

    Dunham, D. W.; Cudnik, B.; Palmer, D. M.; Sada, P. V.; Melosh, J.; Beech, M.; Pellerin, L.; Asher, D.; Frankenberger R.; Venable R.

    2000-01-01

    North American observers recorded at least six meteors striking the Moon's surface during the Leonid meteor shower on 1999 Nov. 18. Each meteor produced a flash that was recorded from at least two separate locations, marking the first confirmed lunar meteor impacts.

  7. 75 FR 15772 - Additional Designations, Foreign Narcotics Kingpin Designation Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-30

    ...; Leonides Guerra No. 97 y Eugenio Lopez No. 97, Colonia San Rafael, Matamoros, Tamaulipas, Mexico; Claveles... RIOJAS, Eleazar; a.k.a. GONZALEZ MARTINEZ, Erick); Cuauhtemoc 805, Nuevo Laredo, Tamaulipas, Mexico; Diaz... Valle Hermoso, Tamaulipas; Alt. POB La Libertad, Cunduacan, Tabasco, Mexico; Alt. POB San...

  8. Onboard photo: Astronauts at work

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Onboard Space Shuttle Columbia (STS-87) mid-deck, Leonid Kadenyuk, Ukrainian payload specialist, works with the Brassica rapa plants being grown for the Collaborative Ukrainian Experiment (CUE). Kadenyuk joined five astronauts for 16-days in Earth-orbit in support of the United States Microgravity Payload 4 (USMP-4) mission.

  9. The Politics of Drug Trafficking in Mexican and Mexico-Related Narconovelas

    ERIC Educational Resources Information Center

    Palaversich, Diana

    2006-01-01

    This essay traces the emergence of the Mexican and Mexico-related narconovela. It examines perspectives on drug trafficking and traffickers expressed in novels by Elmer Mendoza, Leonides Alfaro, Gerardo Cornejo, Homero Aridjis, Arturo Perez-Reverte, and Paul Flores. The variety of positions taken refutes the tendency of the Mexican mainstream…

  10. Meteor Outbursts and Storms from the Spacecraft Hazard Perspective

    NASA Technical Reports Server (NTRS)

    Cooke, William; Moser, Danielle; Suggs, Rob

    2004-01-01

    The recent Leonid meteor storms have propelled meteor shower forecasting from an idea into the realm of practical application, invoked several times per year by numerous spacecraft. This paper will describe shower activity predictions, which give zenith hourly rate (ZHR) as a function of time, and how these are translated into spacecraft risks. Common spacecraft meteor shower mitigation strategies will also be discussed, and the important issue as to when to implement such operations considered. It should be noted that, while the recent meteor storms did not result in the loss of a vehicle, there were a few spacecraft anomalies attributed to Leonid strikes, and the nature of these will be commented upon. Finally, we assess the current state of the art in shower forecasting, and take a look "down the road" at some possible outbursts in the near future.

  11. Generation of infrasonic waves by low-frequency dust acoustic perturbations in the Earth's lower ionosphere

    SciTech Connect

    Kopnin, S. I.; Popel, S. I.

    2008-06-15

    It is shown that, during Perseid, Geminid, Orionid, and Leonid meteor showers, the excitation of low-frequency dust acoustic perturbations by modulational instability in the Earth's ionosphere can lead to the generation of infrasonic waves. The processes accompanying the propagation of these waves are considered, and the possibility of observing the waves from the Earth's surface is discussed, as well as the possible onset of acoustic gravitational vortex structures in the region of dust acoustic perturbations. The generation of such structures during Perseid, Geminid, Orionid, and Leonid meteor showers can show up as an increase in the intensity of green nightglow by an amount on the order of 10% and can be attributed to the formation of nonlinear (vortex) structures at altitudes of 110-120 km.

  12. Polish Automated Video Observations (PAVO)

    NASA Astrophysics Data System (ADS)

    Wiśniewski, M.; Kědzierski, P.; Mularczyk, K.; Złoczewski, K.

    2003-02-01

    We describe the current status of video observations of meteors in Poland. The setup contains four very low light CCTV cameras. The video system has so far made 185 hours of observations. Most of the data comes from Leonids nights. We decided to use the MetRec program for video tape analysis. The data will be fully reduced and presented soon. We made a visual inspection of tapes of the period 03h04m -- 04h13m UT from the night 2002 November 18/19. We detected a rapidly growing number of meteors near the start of the predicted maximum of the Leonid shower. At 04h13m UT clouds fully covered the sky at the Ostrowik Observatory. -------------------------cut here ------------------------------ --0-788132870-1049954275=:69287--

  13. Analysis of Historical Meteor and Meteor shower Records: Korea, China and Japan

    NASA Astrophysics Data System (ADS)

    Yang, Hong-Jin; Park, Changbom; Park, Myeong-Gu

    2015-03-01

    We have compiled and analyzed historical meter and meteor shower records in Korean, Chinese, and Japanese chronicles. We have confirmed the peaks of Perseids and an excess due to the mixture of Orionids, north-Taurids, or Leonids through the Monte-Carlo test from the Korean records. The peaks persist for almost one thousand years. We have also analyzed seasonal variation of sporadic meteors from Korean records. Major features in Chinese meteor shower records are quite consistent with those of Korean records, particularly for the last millennium. Japanese records also show Perseids feature and Orionids/north-Taurids/Leonids feature, although they are less prominent compared to those of Korean or Chinese records.

  14. Stratospheric Sampling and In Situ Atmospheric Chemical Element Analysis During Meteor Showers: A Resource Study

    NASA Technical Reports Server (NTRS)

    Noever, David A.

    2000-01-01

    Resources studies for asteroidal mining evaluation have depended historically on remote sensing analysis for chemical elements. During the November 1998 Leonids meteor shower, a stratospheric balloon and various low-density capture media were used to sample fragments from Comet Tempel-Tuttle debris during a peak Earth crossing. The analysis not only demonstrates how potential sampling strategies may improve the projections for metals or rare elements in astromining, but also benchmarks materials during low temperature (-60 F), high dessication environments as seen during atmospheric exposure. The results indicate high aluminum, magnesium and iron content for various sampled particles recovered, but generalization to the sporadic meteors expected from asteroidal sources will require future improvements in larger sampling volumes before a broad-use strategy for chemical analysis can be described. A repeat of the experimental procedure is planned for the November 1999 Leonids' shower, and various improvements for atmospheric sampling will be discussed.

  15. Ancient Chinese Observations and Modern Cometary Models

    NASA Technical Reports Server (NTRS)

    Yeomans, D. K.

    1995-01-01

    Ancient astronomical observations, primarily by Chinese, represent the only data source for discerning the long-term behavior of comets. These sky watchers produced astrological forecasts for their emperors. The comets Halley, Swift-Tuttle, and Tempel-Tuttle have been observed for 2000 years. Records of the Leonid meteor showers, starting from A.D.902, are used to guide predictions for the 1998-1999 reoccurrence.

  16. Redefinition of the meteor storm from the point of view of spaceflight security

    NASA Astrophysics Data System (ADS)

    Ma, Yuehua; Xu, Pinxin; Li, Guangyu

    ZHR∗ is defined as number of meteoroids passing 1000 km2 zenith area per hour which can produce craters no less than 1 cm in diameter on an aluminum material. The relationship between ZHR and ZHR∗ is deduced. We evaluate the strong meteor showers since 1990s by ZHR∗ instead of ZHR and find the Giacobinid (Draconid) shower in 1998 is much stronger than the Leonid shower in 1999, 2001 and 2002.

  17. Archive of radar observations of meteors in Tomsk in 1965-1966. (Russian Title: Архив радиолокационных наблюдений метеоров в Томске в 1965-1966 гг.)

    NASA Astrophysics Data System (ADS)

    Ryabova, G. O.

    2010-12-01

    The archive of data of radar observations of Geminid, Quadrantid, Daytime Arietid, Perseid, Ursid, Lyrid, Orionid and Leonid meteor showers in Tomsk in 1965-1966 is described. In certain cases registrations of the sporadic background before and after a shower exist. Primary data of echo registrations contain time of a registration, distance, duration and amplitude of an echo, allowing to obtain corresponding distributions essential for calculation of the incident flux density of meteors. Work on the archive digitization has been started.

  18. First years of the Polish Fireball Network

    NASA Astrophysics Data System (ADS)

    Zoladek, P.

    2012-01-01

    The first attempts of video and photographic meteor observations in Poland are presented. The Polish Fireball Network (PFN) was estabilished in 2004 after a succesfull Leonid campaign and the appearance of the Laskarzew fireball. Typical fireball stations were equiped with CCTV systems, with METREC software running. The first digital fireball stations have been created in 2005. Currently, PFN consists of 20 fireball stations and uses 54 CCTV cameras.

  19. Recent meteor showers - models and observations

    NASA Astrophysics Data System (ADS)

    Koten, P.; Vaubaillon, J.

    2015-10-01

    A number of meteor shower outbursts and storms occurred in recent years starting with several Leonid storms around 2000 [1]. The methods of modeling meteoroid streams became better and more precise. An increasing number of observing systems enabled better coverage of such events. The observers provide modelers with an important feedback on precision of their models. Here we present comparison of several observational results with the model predictions.

  20. Meteor Beliefs Project: Seven years and counting

    NASA Astrophysics Data System (ADS)

    McBeath, A.; Drobnock, G. J.; Gheorghe, A. D.

    2010-04-01

    The Meteor Beliefs Project's seventh anniversary is celebrated with an eclectic mixture of meteor beliefs from the 1799 Leonids in Britain, the folkloric link between meteors and wishing in some Anglo-American sources, how a meteoric omen came to feature in Nathaniel Hawthorne's 1850 novel The Scarlet Letter, and a humorous item from the satirical magazine Punch in 1861, all helping to show how meteor beliefs can be transformed by different parts of society.

  1. ESA's experts are ready for a storm of comet dust

    NASA Astrophysics Data System (ADS)

    1998-11-01

    Minute grains of dust create the glowing heads and tails that make comets famous. A trail of dust traces the orbit of each comet, and when the Earth encounters a comet trail the result is a meteor shower. Comet Tempel-Tuttle has just refreshed its dust trail on a visit to the Sun's vicinity, which it makes every 33 years. The Leonids approach the Earth from the direction of the constellation Leo. As a precaution, the Hubble Space Telescope will turn its back on Leo for ten hours around the predicted peak of the Leonid event, which is at about 20:30 CET on 17 November. Astronomers will take the opportunity to look for undiscovered galaxies in the opposite direction in the sky. Any disturbances caused to the 11.6-tonne Hubble spacecraft by the Leonid dust impacts will be recorded for analysis by dust specialists. One of the teams chosen for this study includes ESA and UK scientists and is headed by John Zarnecki of the University of Kent. Zarnecki comments: "It seems like doing an experiment with the crown jewels. But Hubble is a fantastically accurate star pointer, so we should detect wobbles due to quite small impacts. We hope to check our theories about the numbers of grains of different masses. But I'd hate to see any harm come to Hubble," Zarnecki adds. "Or any other spacecraft for that matter." Taking account of the risk to spacecraft This year Comet Tempel-Tuttle passed within 1.2 million kilometres of the Earth's orbit, which is very near by astronomical standards. Similar close encounters have produced widely differing results in the past. In 1932 the count of visible meteors in the Leonids reached an unremarkable rate of 240 per hour, compared with a normal background of about 10-20 sporadic meteors per hour at quiet times. Yet in 1966 the count-rate for the Leonids was 15,000 per hour, or 4 per second, and some observers reported even higher rates. If the rate is again 15,000 per hour, a spacecraft presenting a target of 10 square metres to the Leonid

  2. The Heavens on Fire

    NASA Astrophysics Data System (ADS)

    Littmann, Mark

    1998-10-01

    Meteor succeeded meteor in such rapid succession that it was impossible to count them; at times the sky seemed full of them, and the earth was illuminated as with a morning light. Eye-witness accounts such as this, and every spectacular detail of the Leonids, the greatest meteor showers of all, can be found in the acclaimed The Heavens on Fire. In this volume, author Mark Littmann vividly tells the history of meteors, and especially the Leonids, whose terrifying beauty established meteor science. He traces the history and mythology of meteors, profiles the fascinating figures whose discoveries advanced the field, and explores how meteors have changed the course of life on Earth. Crisp illustrations capture the excitement of past meteor showers and help elucidate important concepts. The returning Leonids are now reaching their peak with great activity expected in 1999 and 2000. For all those who wish to take part in this rare experience, Littmann offers advice on how and where to find the best view. Filled with practical tips, clear explanations, and descriptions of a sight that more than one observer has called "brilliant beyond conception," The Heavens on Fire will delight every reader. Mark Littmann teaches astronomy at the University of Tennessee. His previous books include Comet Halley: Once in a Lifetime and Planets Beyond: Discovering the Outer Solar System. Both books were chosen by the Astronomical Society of the Pacific as Astronomy Books of the Year.

  3. The wave of the future - Searching for gravity waves

    NASA Astrophysics Data System (ADS)

    Goldsmith, Donald

    1991-04-01

    Research on gravity waves conducted by such scientists as Gamov, Wheeler, Weber and Zel'dovich is discussed. Particular attention is given to current trends in the theoretical analysis of gravity waves carried out by theorists Kip Thorne and Leonid Grishchuk. The problems discussed include the search for gravity waves; calculation of the types of gravity waves; the possibility of detecting gravity waves from localized sources, e.g., from the collision of two black holes in a distant galaxy or the collapse of a star, through the Laser Interferometer Gravitational Wave Observatory; and detection primordial gravity waves from the big bang.

  4. Meteor storms and showers with the IMEX model

    NASA Astrophysics Data System (ADS)

    Soja, R. H.; Herzog, J. T.; Sommer, M.; Rodmann, J.; Vaubaillon, J.; Strub, P.; Albin, T.; Sterken, V.; Hornig, A.; Bausch, L.; Grün, E.; Srama, R.

    2015-01-01

    The Interplanetary Meteoroid Environment for Exploration (IMEX) provides a model of meteoroid streams in the inner solar system. It is primarily designed to provide hazard estimations for interplanetary spacecraft. However, such a model is also suited for studying the impact of recently created meteoroid streams at the Earth. It also allows us to study meteor storms, and to automatically determine the streams that can be observed at the Earth at any time. Here we describe the application to Leonid meteor storms of 1999-2002, and provide the results of the automatic stream determination for 2015.

  5. Optical detection of meteoroidal impacts on the Moon

    PubMed

    Ortiz; Sada; Bellot Rubio LR; Aceituno; Aceituno; Gutierrez; Thiele

    2000-06-22

    Impacts of meteoroids on the Moon should cause detectable optical flashes, but the population of objects that are big enough is very low, and hitherto no unambiguous impact flashes have been recorded. The flux of meteoroids associated with the Leonid meteor shower of 18 November 1999 was predicted to produce observable flashes on the night side of the Moon. Here we report the unambiguous detection of five such impact flashes, three of which were seen simultaneously by other observers. We also observed a possible impact flash on 16 July 1999. All of the flashes were of very brief duration (<0.02 s), as expected for high-speed impacts. PMID:10879526

  6. About origin of comet 55P

    NASA Astrophysics Data System (ADS)

    Guliyev, R. A.

    2014-12-01

    55P is a periodic comet with an orbital period of 33 years. It fits the classical definition of a Halley-type comet. The comet is the parent body of the Leonid meteor shower. Orbital simulation of the comet's 55P/Tempel-Tuttle orbit for 5000 years before its discovery by a variety of integrators is provided in this work. In particular the idea of capturing the comet 55P by Uranus from the field of long-period comets during the integration period is checked. The hypothesis about its capture from the Kuiper belt for the study period is checked also. Both ideas have not been confirmed.

  7. STS-87 Payload Specialist Kadenyuk in white room

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine is assisted with final preparations before launch in the white room at Launch Pad 39B by Danny Wyatt, NASA quality assurance specialist, at left; Dave Law, USA mechanical technician, facing Kadenyuk; and Travis Thompson, USA orbiter vehicle closeout chief, at right. STS-87 is the fourth flight of the United States Microgravity Payload and Spartan-201. The 16- day mission will include the Collaborative Ukrainian Experiment (CUE), a collection of 10 plant space biology experiments that will fly in Columbias middeck and will feature an educational component that involves evaluating the effects of microgravity on Brassica rapa seedlings.

  8. The history of meteors and meteor showers

    NASA Astrophysics Data System (ADS)

    Hughes, David W.

    The history of meteors and meteor showers can effectively start with the work of Edmond Halley who overcome the Aristotelean view of meteors as being an upper atmospheric phenomenon and introduced their extraterrestrial nature. Halley also estimated their height and velocity. The observations of the Leonids in 1799, 1833 and 1866 established meteoroids as cometary debris. Two red herrings were caught — fixed radiants and hyperbolic velocities. But the 1890 to 1950 period with two-station meteor photography, meteor spectroscopy and the radar detection of meteors saw the subject well established.

  9. From H.G. Wells to Unmanned Planetary Exploration

    NASA Technical Reports Server (NTRS)

    Boyd, John W.

    2005-01-01

    The possibility of planetary exploration has been a dream of the human race since Galileo discovered the moons of Jupiter in 1610. Visual sightings of bodies entering Earth s atmosphere have been made by Earth s inhabitants over the centuries. Over time, the many meteor showers (Leonid, Perseid) have provided dramatic evidence of the intense heat generated by a body entering Earth s atmosphere at hypervelocity speeds. More recently (in 1908), few viewed the Tunguska meteor that impacted in Siberia, but the destructive power on the countryside was awesome.

  10. Conjoined twins: scientific cinema and Pavlovian physiology.

    PubMed

    Krementsov, Nikolai

    2015-01-01

    Through the lens of a 1957 documentary film, "Neural and humoral factors in the regulation of bodily functions (research on conjoined twins)," produced by the USSR Academy of Medical Sciences, this essay traces the entwined histories of Soviet physiology, studies of conjoined twins and scientific cinema. It examines the role of Ivan Pavlov and his students, including Leonid Voskresenkii, Dmitrii Fursikov and Petr Anokhin, in the development of "scientific film" as a particular cinematographic genre in Soviet Russia and explores numerous puzzles hidden behind the film's striking visuals. PMID:26601729

  11. Prospects for Ukrainian denuclearization after the Moscow trilateral statement

    SciTech Connect

    1994-03-01

    On January 14, at the Moscow summit, Presidents Bill Clinton, Boris Yeltsin of Russia and Leonid Kravchuk of Ukraine issued a trilateral statement that again commits Ukraine to denuclearize in compliance with START I and the Lisbon Protocol and to join the nuclear Non-Proliferation Treaty (NPT) as a non-nuclear-weapon state. Recognizing that scant media attention had been paid to the importance of the trilateral statement, the Arms Control Association (ACA) held a news conference on January 28 to provide background and context on the many issues that affect prospects for Ukrainian denuclearization.

  12. STS-87 Ukrainian Payload Specialist Kadenyuk addresses the media

    NASA Technical Reports Server (NTRS)

    1997-01-01

    As STS-87 Commander Kevin Kregel looks on, Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine addresses members of the press and media at Kennedy Space Center's Shuttle Landing Facility after arriving for the final prelaunch activities leading up to the scheduled Nov. 19 liftoff. Other STS-87 crew members not pictured are Pilot Steven Lindsey; and Mission Specialists Kalpana Chawla, Ph.D.; Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Winston Scott. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  13. STS-87 Ukrainian Payload Specialist Kadenyuk arrives at SLF

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine arrives at Kennedy Space Center's Shuttle Landing Facility aboard a T-38 jet for the final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Commander Kevin Kregel; Pilot Steven Lindsey; and Mission Specialists Kalpana Chawla, Ph.D.; Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Winston Scott. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  14. STS-87 Mission Specialist Chawla and her husband pose at LC 39B

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Mission Specialist Kalpana Chawla, Ph.D., poses with her husband, Jean-Pierre Harrison, in front of Kennedy Space Center's Launch Pad 39B during final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Commander Kevin Kregel; Pilot Steven Lindsey; Mission Specialists Winston Scott and Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  15. STS-87 Commander Kregel and his wife pose at LC 39B

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Commander Kevin Kregel poses with his wife, Jeannie Kregel, in front of Kennedy Space Center's Launch Pad 39B during final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Pilot Steven Lindsey; Mission Specialists Kalpana Chawla, Ph.D., Winston Scott, and Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  16. STS-87 Commander Kregel addresses the media at the SLF

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Commander Kevin Kregel addresses members of the press and media at Kennedy Space Center's Shuttle Landing Facility after arriving for the final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The STS-87 crew members are, from left to right, Mission Specialists Winston Scott and Takao Doi, Ph.D., of the National Space Development Agency of Japan; Commander Kevin Kregel; Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; Mission Specialist Kalpana Chawla, Ph.D.; and Pilot Steven Lindsey. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  17. STS-87 Payload Specialist Kadenyuk and his wife pose at LC 39B

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine poses with his wife, Vera Kadenyuk, in front of Kennedy Space Center's Launch Pad 39B during final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Commander Kevin Kregel; Pilot Steven Lindsey; and Mission Specialists Kalpana Chawla, Ph.D.; Winston Scott; and Takao Doi, Ph.D., National Space Development Agency of Japan. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  18. STS-87 Mission Specialist Doi addresses the media at the SLF

    NASA Technical Reports Server (NTRS)

    1997-01-01

    As STS-87 Commander Kevin Kregel looks on, Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan addresses members of the press and media at Kennedy Space Center's Shuttle Landing Facility after arriving for the final prelaunch activities leading up to the scheduled Nov. 19 liftoff. Other STS-87 crew members not pictured are Pilot Steven Lindsey; Mission Specialists Kalpana Chawla, Ph.D., and Winston Scott; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  19. STS-87 Commander Kregel arrives at the SLF aboard a T-38 jet

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Commander Kevin Kregel arrives at Kennedy Space Center's Shuttle Landing Facility aboard a T-38 jet for the final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Pilot Steven Lindsey; Mission Specialists Kalpana Chawla, Ph.D.; Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Winston Scott; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  20. STS-87 Mission Specialist Doi and his wife pose at LC 39B

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan poses with his wife, Hitomi Doi, in front of Kennedy Space Center's Launch Pad 39B during final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Commander Kevin Kregel; Pilot Steven Lindsey; Mission Specialists Kalpana Chawla, Ph.D., and Winston Scott; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan- 201 deployable satellite.

  1. STS-87 Pilot Lindsey arrives at the SLF aboard a T-38 jet

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Pilot Steven Lindsey arrives at Kennedy Space Center's Shuttle Landing Facility aboard a T-38 jet for the final prelaunch activities leading up to the scheduled Nov. 19 liftoff. The other STS-87 crew members are Commander Kevin Kregel; Mission Specialists Kalpana Chawla, Ph.D.; Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Winston Scott; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  2. Results of forward-scatter radio echo observations in 2000

    NASA Astrophysics Data System (ADS)

    Ueda, Masayoshi; Maegawa, Kimio

    2001-11-01

    We had been performing a forward scatter radio observation of meteor since 1996. The transmitting station was at Fukui (Japan), and the frequency is 53.750 MHz and the power is 50W. The receiving station is Osaka (Japan) and base line has 160 km distance and NE-SW direction. 504,588 meteor echoes have been observed from January to December 2000. Total of radio observation was 8,238 hours. We made the activities of these showers (June), δ Aquarids (July), Perseids (August), Leonids (November), Geminids (December) and Ursids (December). Moreover, we reported the daily variation of mean meteor rates and the annual variation of mean meteor rates.

  3. Meteor44 Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Cooke, William J.

    2004-01-01

    Meteor44 is a software system developed at MSFC for the calibration and analysis of video meteor data. The dynamic range of the (8bit) video data is extended by approximately 4 magnitudes for both meteors and stellar images using saturation compensation. Camera and lens specific saturation compensation coefficients are derived from artificial variable star laboratory measurements. Saturation compensation significantly increases the number of meteors with measured intensity and improves the estimation of meteoroid mass distribution. Astrometry is automated to determine each image's plate coefficient using appropriate star catalogs. The images are simultaneously intensity calibrated from the contained stars to determine the photon sensitivity and the saturation level referenced above the atmosphere. The camera s spectral response is used to compensate for stellar color index and typical meteor spectra in order to report meteor light curves in traditional visual magnitude units. Recent efforts include improved camera calibration procedures, long focal length 'streak' meteor photometry and two-station track determination. Meteor44 has been used to analyze data from the 2001, 2002 and 2003 MSFC Leonid observational campaigns as well as several lesser showers. The software is interactive and can be demonstrated using data from recent Leonid campaigns.

  4. Meteor44 Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Cooke, William J.

    2004-01-01

    Meteor44 is a software system developed at MSFC for the calibration and analysis of video meteor data. The dynamic range of the (8bit) video data is extended by approximately 4 magnitudes for both meteors and stellar images using saturation compensation. Camera and lens specific saturation compensation coefficients are derived from artificial variable star laboratory measurements. Saturation compensation significantly increases the number of meteors with measured intensity and improves the estimation of meteoroid mass distribution. Astrometry is automated to determine each image s plate coefficient using appropriate star catalogs. The images are simultaneously intensity calibrated from the contained stars to determine the photon sensitivity and the saturation level referenced above the atmosphere. The camera s spectral response is used to compensate for stellar color index and typical meteor spectra in order to report meteor light curves in traditional visual magnitude units. Recent efforts include improved camera calibration procedures, long focal length "streak" meteor photome&y and two-station track determination. Meteor44 has been used to analyze data from the 2001.2002 and 2003 MSFC Leonid observational campaigns as well as several lesser showers. The software is interactive and can be demonstrated using data from recent Leonid campaigns.

  5. Possible detection of meteor stream effects on the lunar sodium atmosphere

    NASA Astrophysics Data System (ADS)

    Verani, S.; Barbieri, C.; Benn, C.; Cremonese, G.

    1998-08-01

    We report two sets of observations of sodium emission from the lunar atmosphere. The spectra were taken on two nights having very similar lunar phases, at various distances from the limb. Using Chamberlains model of the exosphere, we obtained values of the temperature, scale height and number density at the surface. These values differ significantly between the two nights. The spectra of the first night were taken when the Earth-Moon system was entering the Leonid meteor stream and show a marked increase in intensity, temperature and scale height relative to those of the second night, and relative to data for similar lunar phases published in the literature. We believe that this increase is related to an enhanced flux of micrometeoroids associated with the Leonid and possible with the Taurid meteor streams. The micrometeoroid component is generally considered the least important contribution to the sodium flux, and its distribution is assumed to be isotropic. We have previously suggested that an anisotropic and enhanced micrometeor component could be associated with meteor streams. The results reported below support this suggestion.

  6. Impact of a major meteor storm on Earth's ionosphere: A modeling study

    NASA Astrophysics Data System (ADS)

    McNeil, William J.; Dressler, Rainer A.; Murad, Edmond

    2001-06-01

    A comprehensive model of the effect of a major meteor storm on Earth's ionosphere is presented. The model includes meteor stream mass distributions based on visual magnitude observations, a differential ablation model of major meteoric metals, Fe and Mg, and state-of-the-art modeling of the chemistry and transport of meteoric metal atoms and ions subsequent to deposition. Particular attention is paid to the possibility of direct ionic deposition of metallic species. The model is validated by calculating the effect of annual meteor showers on the background metal atom and ion abundances. A metallic ion density increase of up to 1 order of magnitude is observed, in agreement with in situ measurements during showers. The model is exercised for a hypothetical Leonid meteor storm of the magnitude reported in 1966. The model predicts the formation of a layer of metal ions in the ionospheric E region that reaches peak densities of around 1×105cm-3, corresponding to a 2 order of magnitude increase of the quiescent nighttime E region density. Although sporadic E layers reaching or exceeding this density are relatively common, the effect is different in that it persists on the order of days and would be observed over nearly one-half the globe. The model predictions are consistent with the available 1966 Leonid storm data. In particular, the observation of enhanced, predawn sporadic E activity points to efficient collisional ionization of meteoric metals, as assumed in the model.

  7. Search for the OH (X(2)Pi) Meinel band emission in meteors as a tracer of mineral water in comets: detection of N(2)(+) (A-X)

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Laux, Christophe O.

    2004-01-01

    We report the discovery of the N(2)(+) A-X Meinel band in the 780-840 nm meteor emission from two Leonid meteoroids that were ejected less than 1000 years ago by comet 55P/Tempel-Tuttle. Our analysis indicates that the N(2)(+) molecule is at least an order of magnitude less abundant than expected, possibly as a result of charge transfer reactions with meteoric metal atoms. This new band was found while searching for rovibrational transitions in the X(2)Pi electronic ground state of OH (the OH Meinel band), a potential tracer of water bound to minerals in cometary matter. The electronic A-X transition of OH has been identified in other Leonid meteors. We did not detect this OH Meinel band, which implies that the excited A state is not populated by thermal excitation but by a mechanism that directly produces OH in low vibrational levels of the excited A(2)Sigma state. Ultraviolet dissociation of atmospheric or meteoric water vapor is such a mechanism, as is the possible combustion of meteoric organics.

  8. The mass and speed dependence of meteor air plasma temperatures

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Laux, Christophe O.; Wilson, Michael A.; Schaller, Emily L.

    2004-01-01

    The speed and mass dependence of meteor air plasma temperatures is perhaps the most important data needed to understand how small meteoroids chemically change the ambient atmosphere in their path and enrich the ablated meteoric organic matter with oxygen. Such chemistry can play an important role in creating prebiotic compounds. The excitation conditions in various air plasma emissions were measured from high-resolution optical spectra of Leonid storm meteors during NASA's Leonid Multi-Instrument Aircraft Campaign. This was the first time a sufficient number and range of temperature measurements were obtained to search for meteoroid mass and speed dependencies. We found slight increases in temperature with decreasing altitude, but otherwise nearly constant values for meteoroids with speeds between 35 and 72 km/s and masses between 10(-5) g and 1 g. We conclude that faster and more massive meteoroids produce a larger emission volume, but not a higher air plasma temperature. We speculate that the meteoric plasma may be in multiphase equilibrium with the ambient atmosphere, which could mean lower plasma temperatures in a CO(2)-rich early Earth atmosphere.

  9. Ukraine President Leonis Kuchma with P.S. Kadenyuk

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Kennedy Space Center, Fla. The president of the Ukraine, Leonid Kuchma, is flanked by Payload Specialist Leonid Kadenyuk, at left, and backup Payload Specialist Yaroslav Pustovyi, at right, both of the National Space Agency of Ukraine, during pre-launch activities leading up to the scheduled Nov. 19 launch of STS-87. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite. During the mission, Kadenyuk will pollinate Brassica rapa plants as part of the Collaborative Ukrainian Experiment, or CUE, aboard Columbia during its 16-day mission. The CUE experiment is a collection of 10 plant space biology experiments that will fly in Columbias middeck and features an educational component that involves evaluating the effects of microgravity on Brassica rapa seedlings. Students in Ukrainian and American schools will participate in the same experiment on the ground and have several live opportunities to discuss the experiment with Kadenyuk in Space. Kadenyuk will be flying his first Shuttle mission on STS- 87.

  10. Astronomical and physical data for meteoroids recorded by the ALTAIR radar

    NASA Astrophysics Data System (ADS)

    Brown, P.; Hunt, S.; Close, S.

    2001-11-01

    We present preliminary results of orbital and physical measurements of a small selection of meteoroids observed at UHF frequencies by the ALTAIR radar on Kwajalein island on November 17, 1998. The head echoes observed by ALTAIR allowed precise determination of velocities and decelerations from which orbits and masses of individual meteoroids derived from numerical modelling have been measured. During these observations, the ALTAIR radar detected average head echo rates of 1665 per hour. The effective system limiting magnitude is found to be between magnitude +10.5 and +11 corresponding to masses near 6×10-10kg using an observed mean velocity of our analyzed sample of 56 km s-1. This compares favorably to a mean modelled initial mass from the observed decelerations of the largest events of near 2×10-9kg. All observations were made with the antenna beam pointing very near the center of the north apex sporadic source. The resulting orbits determined from modelling are largely consistent with the orbital characteristics of that source derived from other radar orbital surveys. Despite these observations occurring near the time of the expected Leonid maximum in 1998, no definite Leonids were detected in our analyzed sample.

  11. On fragmentation of meteoroids in interplanetary space

    NASA Astrophysics Data System (ADS)

    Porubčan, V.; Tóth, J.; Yano, H.

    2002-10-01

    A possible fragmentation of meteoroids in interplanetary space inferred from grouping of particles in meteor streams is discussed. There is a conviction maintained by many observers that meteors within the streams are observed to be clustered in pairs or larger groups more frequently than one could expect from random distribution. The rate of dispersive effects indicates that the lifetime of any such a group of meteoroids is very limited. Therefore, if real, the pairs or groups must be due to recent fragmentation of larger meteoroids. Analyses based on visual observations of meteor streams lead to contradictory results. More conclusive are analyses based on radio measurements, which present a negative result concerning the permanent meteor showers with the stream structures at their middle and late evolutionary stages, and an indication of a positive result for younger dense stream structures of recent origin. Analysis of the 1969 Leonid display obtained by the Springhill high-power radar shows that about 10% of the population around the shower maximum is associated in close groups, within a distance up to of about 10 km and confined to an effective stream width comparable to the diameter of the Earth. The recent Leonid returns with the storm in 1999 provided a possibility to verify a non-random grouping of particles within this young filament of the stream. The analysis and results based on TV observations of the storm are presented and discussed.

  12. An Evaluation of the Accuracy of Meteor Shower Forecasts

    NASA Technical Reports Server (NTRS)

    Cooke, W.; Moser, D.

    2004-01-01

    Brought into being by the recent Leonid meteor storms, meteor shower forecasts are now regarded by many spacecraft projects as necessary inputs into the planning of spacecraft operations. We compare the shower forecasts made by various researchers over the past six years to actual shower observations in an attempt to create an overall picture of forecast accuracy, specifically focusing on the three aspects most important to space vehicles: 1) the time of shower maximum, 2) the half-width (duration), and 3) the maximum Zenith Hourly Rate (ZHR). It will be noted that, while the times of maxima are generally predicted to within several minutes, the peak ZHRs are often overestimated and shower half-widths are frequently not even calculated. The difficulties involved in converting shower ZHRs into the meteoroid fluxes needed to assess spacecraft risk are also discussed.

  13. Bridging the Gap Between Atomistics and Structural Engineering

    NASA Astrophysics Data System (ADS)

    Langer, J. S.

    When Sid Yip asked me to write a commentary for this section of the handbook, I promptly reminded him that I am a co-author of a longer article in the section on mathematical methods. I told him that my article on amorphous plasticity, written with Michael Falk and Leonid Pechenik, already is more of a departure from conventional ideas than may be appropriate for a book like this one, which should serve as a reliable reference for years into the future; and I asked whether I really ought to be given yet more space for expressing my opinions. Sid insisted that I should write the commentary anyway. So here are some remarks about one of the topics of interest in this book, the search for predictive models of deformation and failure of solids, and the role of nonequilibrium physics in this effort.

  14. SPA Meteor Section Results: 2007

    NASA Astrophysics Data System (ADS)

    McBeath, Alastair

    2013-08-01

    Information extracted from analyses carried out by the SPA Meteor Section from 2007 is presented and discussed. Events covered include: the radio Quadrantid maximum on January 4; a bright fireball seen from parts of England and imaged from the Netherlands at 19h56m UT on February 6, for which an approximate trajectory was established; radio results from the Lyrids in late April; the Perseid near-peak activity from August and a note on some daylight Perseid observing from Britain using thermal imagers; the radio α-Aurigid maximum on September 1; the Orionid return, which again provided enhanced activity over several consecutive dates in October for visual and radio observers; the radio Leonids, although the probably main peak found visually on November 19 was not recorded thus due to its timing; the typically protracted Geminid maximum period around December 13-15 as observed visually and by radio; and the Ursid outburst, primarily as detected by radio on December 22.

  15. Radar meteors range distribution model. III. Ablation, shape-density and self-similarity parameters

    NASA Astrophysics Data System (ADS)

    Pecinová, D.; Pecina, P.

    2007-10-01

    The theoretical radar meteors Range Distribution of the overdense echoes developed by Pecinová and Pecina (2007 a) is applied here to observed range distributions of meteors belonging to the Quadrantid, Perseid, Leonid, Geminid, γ Draconid (Giacobinid), ζ Perseid and β Taurid streams to study the variability of the shape-density, ablation, and self-similarity parameters of meteoroids of these streams. We have found in accordance with results of photographical observations that ablation parameter σ is higher for members of showers of clearly cometary origin, and is lower for Geminid and daytime shower meteoroids. Levin's self-similarity parameter μ was found to be much greater than the classical value 2/3 for all investigated streams with the exception of Geminids, for which the value found is almost classical, i.e. 0.66 ± 0.01. The method of getting μ by means of fitting the light curve of faint TV meteors is also suggested.

  16. STS-87 crew members in front of T-38 at SLF

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 astronaut crew members prepare to fly back to Johnson Space Center in Houston after participating in the Crew Equipment Integration Test (CEIT) at Kennedy Space Center (KSC) in early October. From left are Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Mission Specialist Winston Scott; Commander Kevin Kregel; Pilot Steven Lindsey; and Mission Specialist Kalpana Chawla, Ph.D. The CEIT gives astronauts an opportunity to get a hands-on look at the payloads with which they will be working on-orbit. STS-87 will be the fourth United States Microgravity Payload and flight of the Spartan-201 deployable satellite. During the STS-87 mission, scheduled for a Nov. 19 liftoff from KSC, Dr. Doi and Scott will both perform spacewalks.

  17. The breast: from Ancient Greek myths to Hippocrates and Galen.

    PubMed

    Iavazzo, C R; Trompoukis, C; Siempos, I I; Falagas, M E

    2009-01-01

    This is a historical article about Ancient Greek literature from mythological times until the first centuries AD with regard to the female breast. We endeavoured to collect several elegant narratives on the topic as well as to explore the knowledge of Ancient Greek doctors on the role, physiology and pathology of breast and the treatment of its diseases. We identified such descriptions in myths regarding Amazons, Hercules, Zeus, Hera and Amaltheia. Furthermore, descriptions on the topic were also found in the work of Hippocrates, Aristoteles, Soranos, Alexander of Aphrodisias, Celsus, Archigenis, Leonides, Galen and Oribasius. We may conclude that some of today's medical knowledge or practice regarding the breast was also known in the historical period. PMID:19891848

  18. Extraterrestrial meteors: a martian meteor and its parent comet.

    PubMed

    Selsis, Franck; Lemmon, Mark T; Vaubaillon, Jérémie; Bell, James F

    2005-06-01

    Regular meteor showers occur when a planet approaches the orbit of a periodic comet--for example, the Leonid shower is evident around 17 November every year as Earth skims past the dusty trail of comet Tempel-Tuttle. Such showers are expected to occur on Mars as well, and on 7 March last year, the panoramic camera of Spirit, the Mars Exploration Rover, revealed a curious streak across the martian sky. Here we show that the timing and orientation of this streak, and the shape of its light curve, are consistent with the existence of a regular meteor shower associated with the comet Wiseman-Skiff, which could be characterized as martian Cepheids. PMID:15931208

  19. Systolic time intervals after a seven-day orbital flight

    NASA Astrophysics Data System (ADS)

    Groza, P.; Vrâncianu, R.; Lazǎr, M.; Baevski, R. M.; Funtova, V. L.

    Heart rate, systolic time intervals (pre-ejection period, left ventricular ejection time), ejection fraction, stroke volume and QT interval of two cosmonauts (Leonid Popov - L.P. and Dumitru Prunariu - D.P.) were studied before, during, and after an ergometric bicycle exercise test performed before and after the seven-day Soviet-Romanian orbital flight on the Soyuz 40 - Salyut 6 Complex in May 1981. For this purpose one precordial electrocardiogram (ecg) and the ear photodensitogram (den) were recorded stimulaneously. The method used permitted recording even during exercise, Ecg and den signals were stored on magnetic tape, processed in an analogue device and in a digital computer. The data obtained after landing suggest a slight cardiac deconditioning in L.P., demonstrated especially by augmentation of the pre-ejection period, which was unchanged in D.P. corresponding to a sympathoadrenergic hypertonia. The seven-day orbital flight has not produced important cardiovascular changes.

  20. Massive Remnant of Evolved Cometary Dust Trail Detected in the Orbit of Halley-Type Comet 55P/Tempel-Tuttle

    NASA Technical Reports Server (NTRS)

    Jenniskens, P.; Betlem, H.

    2000-01-01

    There is a subpopulation of Leonid meteoroid stream particles that appear to form a region of enhanced numbers density along the path of the stream. This structure has been detected in the vicinity of the parent comet, and its variation from one apparition to the next has been traced. A significant amount of known comet 55P/Tempel-Tuttle debris is in this component, called a "filament," which has dimensions exceeding by an order of magnitude that expected for a cometary dust trail. As filament particles are of a size comparable to those found in trails, the emission ages of the particles comprising the filament must be intermediate between the age of the current trail particles (which have not been observed) and the age of the background particles comprising the annual showers. The most likely explanation for this structure is planetary perturbations acting differently on the comet and large particles while at different mean anomalies relative to each other.

  1. Anomalous meteors from the observations with super-isocon TV systems

    NASA Astrophysics Data System (ADS)

    Kozak, P.; Watanabe, J.; Sato, M.

    2014-07-01

    There is a range of both optical and radar observations of meteors the behavior of which essentially differs from the behavior of most meteors. In some cases such meteors cannot be explained in the frame of the classic physical theory of meteors, in other cases the meteors are just of rare type. First of all these are the meteors with true hyperbolic velocities. In spite of the fact that most of hyperbolic orbits are the results of calculation errors, the meteors with extremely high velocities appreciably exceeding the hyperbolic limit of 73 km/s exist and can be of interstellar origin [1--3]. Another very rare phenomenon describes the possible cluster structure of meteor streams, which could be connected with the ejection of the substance from the cometary nucleus shortly before collision of the particles with the Earth [4]. Among anomalies connected with the meteor motion in the atmosphere one can note, first of all, the ultra-high altitudes of meteor beginnings exceeding 130--140 km [5--7]. Some other observations point to the beginning heights of bright meteors from Leonid shower on altitudes near 200 km [8]. The classic physical theory of meteors cannot explain their radiation on such high altitudes because of low air density [9]. Recently the results of TV observations of meteors with diffusive and cloudy structure appeared [9,10]. The results of observations in which, according to author's opinion, the meteors have a few kilometers transverse jets [9--11] were presented as well. There are video frames with bright meteor obtained with high temporal resolution, where authors declared the radiation, which could be an effect of a spread directly of the shock wave [12]. During many years' double-station observations of meteors which have been carrying out at Astronomical Observatory of Kyiv National Taras Shevchenko University the ultra-sensitive TV transmitting tubes of super-isocon type were used [7]. Given type of the tube is one of the most sensitive in the

  2. Some problems of the theory of gravitation

    NASA Astrophysics Data System (ADS)

    Verozub, Leonid

    Leonid Verozub, lverozub@gmail.com Kharkov National University, Kharkov, Ukraine The contemporary observations pose serious challenges to the fundamental physics and astro-physics. We proceed from the equations of gravitation, based on an examination of foundations of the theory. (Ann. Phys. (Leipzig) 17, No. 1, 28 -51 (2008)). Namely, these equations are based on going back to Poincare's ideas about the relativity of geometry of space and time to the properties of measuring instruments, and on the consideration of the geodesic invariance as gauge invariance in the theory of gravitation. These equations do not contradict the observa-tional data, however, lead to two unexpected consequences, which allow you to test the theory: 1. They predict the existence of super-massive compact objects without event horizons, which are an alternative to black holes in the centers of galaxies. 2. They provide a simple and natural explanation for the accelerating expansion of the universe.

  3. STS 87: Meal - Suit Up - Depart O&C - Launch Columbia On Orbit - Landing - Crew Egress

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The STS-87 Space Shuttle Columbia mission begins with the introduction of the seven crew members. The seven crew members include: Commander Kevin R. Kregel, pilot Steven W. Lindsey, mission specialists: Winston E. Scott, Kalpana Chawla and Takao Doi and payload specialist Leonid K. Kadenyuk. The United States Microgravity Payload (USMP-4), Orbital Acceleration Research Experiment (OARE), the EVA Demonstration Flight Test 5 (EDFT-05), Shuttle Ozone Limb Sending Experiment (SOLSE), Loop Heat Pump (LHP), and Sodium Sulfur Battery Experiment (NaSBE) were all shown during this video presentation. The launch of the STS-87 from different Kennedy Space Flight Center (KSFC) areas and Pre-flight training at the Johnson Space Center is presented. The retrieve and recovery spot satellite are also shown. Also, the landing of the Space Shuttle Columbia is presented from different areas at Kennedy Space Flight Center.

  4. Meteor storm evidence against the recent formation of lunar crater Giordano Bruno

    NASA Astrophysics Data System (ADS)

    Withers, Paul

    2001-04-01

    It has been suggested that the formation of the 22 km diameter lunar crater Giordano Bruno was witnessed in June 1178 A.D. To date, this hypothesis has not been well tested. Such an impact on the Earth would be "civilization threatening". Previous studies have shown that the formation of Giordano Bruno would lead to the arrival of 10 million tonnes of ejecta in the Earth's atmosphere in the following week. I calculate that this would cause a week-long meteor storm potentially comparable to the peak of the 1966 Leonids storm. The lack of any known historical records of such a storm is evidence against the recent formation of Giordano Bruno. Other tests of the hypothesis are also discussed, with emphasis on the lack of corroborating evidence for a very recent formation of the crater.

  5. STS-87 crew participates in Crew Equipment Interface Test

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 astronaut crew members participate in the Crew Equipment Integration Test (CEIT) with the Spartan-201 payload in Kennedy Space Centers (KSC's) Vertical Processing Facility. From left are Pilot Steven Lindsey; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Mission Specialist Kalpana Chawla, Ph.D.; Commander Kevin Kregel; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. The CEIT gives astronauts an opportunity to get a hands- on look at the payloads with which they will be working on-orbit. STS-87 will be the fourth United States Microgravity Payload and flight of the Spartan-201 deployable satellite. During the mission, Dr. Doi will be the first Japanese astronaut to perform a spacewalk. STS-87 is scheduled for a Nov. 19 liftoff from KSC.

  6. STS-87 Payload Specialist Kadenyuk participates in the CEIT for his mission

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Participating in the Crew Equipment Integration Test (CEIT) at Kennedy Space Center is STS-87 Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine (NSAU). Here, Cosmonaut Kadenyuk is inspecting flowers for pollination and fertilization, which will occur as part of the Collaborative Ukrainian Experiment, or CUE, aboard Columbia during its 16-day mission, scheduled to take off from KSC's Launch Pad 39-B on Nov. 19. The CUE experiment is a collection of 10 plant space biology experiments that will fly in Columbia's middeck and feature an educational component that involves evaluating the effects of microgravity on the pollinating Brassica rapa seedlings. Students in Ukrainian and American schools will participate in the same experiment on the ground and have several live opportunities to discuss the experiment with Kadenyuk in Space. Kadenyuk of the Ukraine will be flying his first Shuttle mission on STS-87.

  7. STS-87 Columbia Launch

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Like a rising sun lighting up the afternoon sky, the Space Shuttle Columbia soars from Launch Pad 39B at 2:46:00 p.m. EST, November 19, on the fourth flight of the United States Microgravity Payload and Spartan-201 satellite. The crew members include Mission Commander Kevin Kregel.; Pilot Steven Lindsey; Mission Specialists Kalpana Chawla, Ph.D., Winston Scott, and Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 16-day STS-87 mission, the crew will oversee experiments in microgravity; deploy and retrieve a solar satellite; and test a new experimental camera, the AERCam Sprint. Dr. Doi and Scott also will perform a spacewalk to practice International Space Station maneuvers.

  8. STS-87 Columbia Landing at KSC

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With Commander Kevin Kregel and Pilot Steven Lindsey at the controls, the orbiter Columbia touches its main gear down on Runway 33 at KSCs Shuttle Landing Facility at 7:20:04 a.m. EST Dec. 5 to complete the 15-day, 16-hour and 34-minute-long STS-87 mission of 6.5 million miles. Also onboard the orbiter are Mission Specialists Winston Scott; Kalpana Chawla, Ph.D.; and Takao Doi, Ph.D., of the National Space Development Agency of Japan; along with Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  9. STS-87 Columbia landing at KSC (Drag Chute Deployed)

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With Commander Kevin Kregel and Pilot Steven Lindsey at the controls, the orbiter Columbia touches its main gear down on Runway 33 at KSCs Shuttle Landing Facility at 7:20:04 a.m. EST Dec. 5 to complete the 15-day, 16-hour and 34-minute-long STS-87 mission of 6.5 million miles. Also onboard the orbiter are Mission Specialists Winston Scott; Kalpana Chawla, Ph.D.; and Takao Doi, Ph.D., of the National Space Development Agency of Japan; along with Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  10. STS-87 concludes with landing of orbiter Columbia at KSC

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With Commander Kevin Kregel and Pilot Steven Lindsey at the controls, the orbiter Columbia makes a smooth touchdown on Runway 33 at KSC's Shuttle Landing Facility at 7:20:04 a.m. EST Dec. 5, completing the 15-day, 16-hour and 34-minute-long STS-87 mission of 6.5 million miles. Also onboard the orbiter are Mission Specialists Winston Scott; Kalpana Chawla, Ph.D.; and Takao Doi, Ph.D., of the National Space Development Agency of Japan; along with Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  11. STS-87 Crew walkout of O&C building

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of Mission STS-87 depart from the Operations and Checkout Building en route to Launch Pad 39B, where the Space Shuttle Columbia awaits liftoff on the fourth flight of the United States Microgravity Payload and the Spartan-201deployable satellite. They are, from left to right, front to back: Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Mission Specialist Winston Scott (near van); Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; and Pilot Steven Lindsey (near van). Missing from this photo are Commander Kevin Kregel and Mission Specialist Kalpana Chawla, Ph.D. The Space Shuttle Columbia and its crew of six members are scheduled to lift off during a two-and-a-half hour launch window, which opens at 2:46 p.m.

  12. STS-87 Crew Breakfast

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The STS-87 flight crew enjoys the traditional pre-liftoff breakfast in the crew quarters of the Operations and Checkout Building. They are, from left, Mission Specialist Winston Scott; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Commander Kevin Kregel; Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; Mission Specialist Kalpana Chawla, Ph.D.; and Pilot Steven Lindsey. After a weather briefing, the flight crew will be fitted with their launch and entry suits and depart for Launch Pad 39B. Once there, they will take their positions in the crew cabin of the Space Shuttle Columbia to await liftoff during a two-and-a-half-hour window that will open at 2:46 p.m. EDT, Nov. 19.

  13. STS-87 Crew walkout of O&C building

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of Mission STS-87 depart from the Operations and Checkout Building en route to Launch Pad 39B, where the Space Shuttle Columbia awaits liftoff on the fourth flight of the United States Microgravity Payload and the Spartan-201deployable satellite. Leading the way are, from left to right, front to back: Mission Specialist Kalpana Chawla, Ph.D.; Commander Kevin Kregel; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Mission Specialist Winston Scott; Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; and Pilot Steven Lindsey. The Space Shuttle Columbia and its crew of six members are scheduled to lift off during a two-and-a-half hour launch window, which opens at 2:46 p.m.

  14. STS-87 Columbia landing at KSC

    NASA Technical Reports Server (NTRS)

    1997-01-01

    With Commander Kevin Kregel and Pilot Steven Lindsey at the controls, the orbiter Columbia makes a smooth touchdown on Runway 33 at KSCs Shuttle Landing Facility at 7:20:04 a.m. EST Dec. 5, completing the 15-day, 16-hour and 34-minute-long STS-87 mission of 6.5 million miles. Also onboard the orbiter are Mission Specialists Winston Scott; Kalpana Chawla, Ph.D.; and Takao Doi, Ph.D., of the National Space Development Agency of Japan; along with Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  15. The STS-87 crew members and their spouses pose in front of Columbia at LC 39B

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of STS-87 pose with their spouses in front of Kennedy Space Center's Launch Pad 39B during final prelaunch activities leading up to the scheduled Nov. 19 liftoff. From left to right are: Vera Kadenyuk, wife of Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine who is next to Vera; Mission Specialist Winston Scott and his wife, Marilyn; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan, and his wife, Hitomi; Jeannie Kregel, who is married to Commander Kevin Kregel standing next to her; Mission Specialist Kalpana Chawla, Ph.D., and her husband, Jean-Pierre Harrison; and Pilot Steven Lindsey and his wife Diane. STS-87 will be the fourth flight of the United States Microgravity Payload and the Spartan-201 deployable satellite.

  16. STS-87 Crew arrives at KSC for TCDT

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Kennedy Space Center (KSC) Director Roy Bridges, at far left, shakes the hand of Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency (NASDA) of Japan. During the STS-87 mission, scheduled for launch on Nov. 19, Dr. Doi will become the first Japanese astronaut to conduct a spacewalk. Pointing to Dr. Doi is Mission Commander Kevin Kregel, who will lead the crew of one other veteran space flyer and four rookies on mission STS-87 aboard the Shuttle Columbia. Kregel is a veteran of two space flights (STS-70 and -78). Next to Kregel is Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. The crew arrived at KSC on Nov. 3 to conduct the Terminal Countdown Demonstration Test (TCDT), held at KSC prior to each Space Shuttle flight to provide the crew with opportunities to participate in simulated countdown activities.

  17. STS-87 M.S. Doi and Chawla and P.S. Kadenyuk in slidewire basket

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of the STS-87 mission, scheduled for launch Nov. 19 aboard the Space Shuttle Columbia from pad 39B at Kennedy Space Center (KSC), participates in the Terminal Countdown Demonstration Test (TCDT) at KSC. Testing a slide wire basket that is part of the pads emergency egress system are, from left, Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine (NSAU); and Mission Specialist Kalpana Chawla, Ph.D. The TCDT is held at KSC prior to each Space Shuttle flight providing the crew of each mission opportunities to participate in simulated countdown activities. The TCDT ends with a mock launch countdown culminating in a simulated main engine cut-off. The crew also spends time undergoing emergency egress training exercises at the pad and has an opportunity to view and inspect the payloads in the orbiter's payload bay.

  18. Comment on the paper 'On the influx of small comets into the earth's upper atmosphere'

    NASA Technical Reports Server (NTRS)

    Soter, Steven

    1987-01-01

    The possibility that comets containing up to 100 tons of ice encounter the earth's atmosphere at a rate of one every 20 min is discussed. Cometary 'hail storms' were proposed to explain observed regular transient decreases in the atmospheric UV dayglow intensity. The decreases take the form of dark 'holes' up to 50 km across. The probability that clouds of objects assumed to be as dark as the nucleus of Comet Halley between the earth and moon would be detectable by ground-based electrooptical deep space telescopes is considered. Conflicting projections of the number of objects which would be detected per hour are examined. High correlations are noted between cometary passages (Comets Encke, Tuttle, Tempel) and intervals of meteor showers (Taurids, Leonids, Geminis, etc.). The holes, however, are not correlated or coincident with the showers. It is suggested that dedicated searches for the unclassified dark objects be carried out in November, when cometary fluxes are high.

  19. Near-Earth Object (NEO) Hazard Background

    NASA Technical Reports Server (NTRS)

    Mazanek, Daniel D.

    2005-01-01

    The fundamental problem regarding NEO hazards is that the Earth and other planets, as well as their moons, share the solar system with a vast number of small planetary bodies and orbiting debris. Objects of substantial size are typically classified as either comets or asteroids. Although the solar system is quite expansive, the planets and moons (as well as the Sun) are occasionally impacted by these objects. We live in a cosmic shooting gallery where collisions with Earth occur on a regular basis. Because the number of smaller comets and asteroids is believed to be much greater than larger objects, the frequency of impacts is significantly higher. Fortunately, the smaller objects, which are much more numerous, are usually neutralized by the Earth's protective atmosphere. It is estimated that between 1000 and 10,000 tons of debris fall to Earth each year, most of it in the form of dust particles and extremely small meteorites. With no atmosphere, the Moon's surface is continuously impacted with dust and small debris. On November 17 and 18, 1999, during the annual Leonid meteor shower, several lunar surface impacts were observed by amateur astronomers in North America. The Leonids result from the Earth's passage each year through the debris ejected from Comet Tempel-Tuttle. These annual showers provide a periodic reminder of the possibility of a much more consequential cosmic collision, and the heavily cratered lunar surface acts a constant testimony to the impact threat. The impact problem and those planetary bodies that are a threat have been discussed in great depth in a wide range of publications and books, such as The Spaceguard Survey , Hazards Due to Comets and Asteroids, and Cosmic Catastrophes. This paper gives a brief overview on the background of this problem and address some limitations of ground-based surveys for detection of small and/or faint near-Earth objects.

  20. Studies of Transient Meteor Activity

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter M. M.

    2002-01-01

    Meteoroids bombard Earth's atmosphere daily, but occasionally meteor rates increase to unusual high levels when Earth crosses the relatively fresh ejecta of comets. These transient events in meteor activity provide clues about the whereabouts of Earth-threatening long-period comets, the mechanisms of large-grain dust ejection from comets, and the particle composition and size distribution of the cometary ejecta. Observations of these transient events provide important insight in natural processes that determine the large grain dust environment of comets, in natural phenomena that were prevalent during the time of the origin of life, and in processes that determine the hazard of civilizations to large impacts and of man-made satellites to the periodic blizzard of small meteoroids. In this proposal, three tasks form a coherent program aimed at elucidating various aspects of meteor outbursts, with special reference to planetary astronomy and astrobiology. Task 1 was a ground-based effort to observe periods of transient meteor activity. This includes: (1) stereoscopic imaging of meteors during transient meteor events for measurements of particle size distribution, meteoroid orbital dispersions and fluxes; and (2) technical support for Global-MS-Net, a network of amateur-operated automatic counting stations for meteor reflections from commercial VHF radio and TV broadcasting stations, keeping a 24h vigil on the level of meteor activity for the detection of new meteor streams. Task 2 consisted of ground-based and satellite born spectroscopic observations of meteors and meteor trains during transient meteor events for measurements of elemental composition, the presence of organic matter in the meteoroids, and products generated by the interaction of the meteoroid with the atmosphere. Task 3 was an airborne effort to explore the 2000 Leonid meteor outbursts, which are anticipated to be the most significant of transient meteor activity events in the remainder of the

  1. The nature of near-Earth meteor streams from comets

    NASA Astrophysics Data System (ADS)

    Van Flandern, T.

    2002-05-01

    Following the embarrassing failure of the predicted return of a Leonid meteor storm in 1998 following the return of the parent comet, Tempel-Tuttle, a dozen groups of astronomers set out to solve the problem of predicting future meteor storms. The first success in history was achieved in 1999, when three of the groups predicted the time and place correctly to within ten minutes. These three successes were all based on the meteor stream concept, and the idea that comets release a new meteor stream at every return to perihelion. However, of the three successes, only the Lyytinen prediction based on the Van Flandern comet model got the meteor rates correct to within a factor of two. The next-best model by Asher & McNaught was off by a factor of eight. Continued success was achieved in 2000 and 2001, when the Earth again encountered various Leonid meteor streams released from the comet centuries ago. The Lyytinen-Van Flandern predictions were again closest, and that model was the only one to correctly predict an outburst of the Ursids in December 2001. This shows that the model is general enough to apply to other comets and meteor streams, and does not need a history of observed encounters to set various adjustable parameters as the other models do. In all, eight shower or storm peaks have now been predicted correctly. This tells us about the nature of comets, about how meteor streams in the inner solar system evolve over time, and about hazards in the near-Earth environment associated with these now-predictable meteor storms.

  2. Meteors do not break exogenous organic molecules into high yields of diatomics

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Schaller, Emily L.; Laux, Christophe O.; Wilson, Michael A.; Schmidt, Greg; Rairden, Rick L.

    2004-01-01

    Meteoroids that dominate the Earth's extraterrestrial mass influx (50-300 microm size range) may have contributed a unique blend of exogenous organic molecules at the time of the origin of life. Such meteoroids are so large that most of their mass is ablated in the Earth's atmosphere. In the process, organic molecules are decomposed and chemically altered to molecules differently from those delivered to the Earth's surface by smaller (<50 microm) micrometeorites and larger (>10 cm) meteorites. The question addressed here is whether the organic matter in these meteoroids is fully decomposed into atoms or diatomic compounds during ablation. If not, then the ablation products made available for prebiotic organic chemistry, and perhaps early biology, might have retained some memory of their astrophysical nature. To test this hypothesis we searched for CN emission in meteor spectra in an airborne experiment during the 2001 Leonid meteor storm. We found that the meteor's light-emitting air plasma, which included products of meteor ablation, contained less than 1 CN molecule for every 30 meteoric iron atoms. This contrasts sharply with the nitrogen/iron ratio of 1:1.2 in the solid matter of comet 1P/Halley. Unless the nitrogen content or the abundance of complex organic matter in the Leonid parent body, comet 55P/Tempel-Tuttle, differs from that in comet 1P/Halley, it appears that very little of that organic nitrogen decomposes into CN molecules during meteor ablation in the rarefied flow conditions that characterize the atmospheric entry of meteoroids approximately 50 microm-10 cm in size. We propose that the organics of such meteoroids survive instead as larger compounds.

  3. Scattering characteristics of high-resolution meteor head echoes detected at multiple frequencies

    NASA Astrophysics Data System (ADS)

    Close, S.; Oppenheim, M.; Hunt, S.; Dyrud, L.

    2002-10-01

    Meteor data collected at the Kwajalein Missile Range (KMR) during the peak of the 1998 Leonid storm comprise the only simultaneous observations of meteor head echoes and trails using seven frequencies (very high frequency (VHF), ultrahigh frequency (UHF), L-, S-, C-, Ka-, and W-band spanning 160 MHz to 95 GHz). The primary sensor was the ARPA Long-Range Tracking and Instrumentation Radar (ALTAIR) radar operating at 160 MHz with 30 m range resolution and 422 MHz with 7.5 m range resolution, including both interferometric and polarization capabilities. This paper presents an analysis of this high-resolution data set with the following results: First, these observations support the theory that head echo scattering arises from an ionized region with a density sufficiently high that its plasma frequency exceeds the radar frequency (overdense reflection). Second, radar cross section (RCS) decreases rapidly with decreasing wavelength because higher frequencies must penetrate further into the increasing density of the plasma surrounding the meteoroid to reach its reflection point. Third, head echo angle measurements indicate that most of the observed meteors are sporadics not originating from the Leonid radiant. Fourth, polarization ratios showed that head echo reflections result from plasmas with a circular cross section. Fifth, the highest RCS values are detected near 105 km altitude, where the meteoroid gives up the most kinetic energy during its decent. This paper presents the first analyses of a three-frequency head echo as well as the polarization ratios and RCS characteristics from numerous two-frequency head echoes, which will allow us to develop a better understanding of meteor physics.

  4. Obituary: Kenneth L. Franklin, 1923-2007

    NASA Astrophysics Data System (ADS)

    Rao, Joe; Degrasse Tyson, Neil

    2007-12-01

    Renowned astronomer and astronomy popularizer Kenneth L. Franklin died early Monday morning, June 18, 2007, in Boulder, Colorado, two weeks after undergoing heart surgery. He was 84 years old. Kenneth Linn Franklin, the only child of Myles and Ruth (Houston) Franklin, was born March 25, 1923 in Alemeda, California. Ken obtained his Ph.D. in astronomy in 1953 at the University of California, Berkeley. From 1954 to 1956 he was a research fellow in radio astronomy at the Department of Terrestrial Magnetism, Carnegie Institution of Washington, DC. While there, he and Bernard F. Burke discovered radio emissions from the planet Jupiter. They announced their find on April 6, 1955, at a meeting of the American Astronomical Society (AAS). In 1956 Ken joined the staff of the American Museum-Hayden Planetarium, where he later served as chairman and chief scientist. Over the course of thirty years he wrote and/or presented innumerable sky shows for the planetarium sky theater, taught popular and technical courses in astronomy, and answered questions from the public. Ken was frequently consulted by local industries engaged in the space program, as well as by the news media and publishers. He was often interviewed on local and national radio and television, especially when a celestial event of special interest was due to occur. On the first page of the November 1966 issue of Sky & Telescope, in comments about the upcoming Leonid meteor shower, Franklin stuck his neck out. Based on some calculations that he'd made, he said he felt we were going to be in for a "interesting display." His was one of the few forecasts that suggested the '66 Leonids might be memorable. As it turned out, he was right — that year observers experienced the now-legendary Leonid meteor storm. From 1973 to 1979, Ken was the AAS's public-affairs officer. For two decades he also served in the society's Harlow Shapley Visiting Lecturer Program, speaking at one or two colleges each year. Ken was an active

  5. The 2011 Draconid Shower Risk to Earth-Orbiting Satellites

    NASA Technical Reports Server (NTRS)

    Cooke, William J.; Moser, Danielle E.

    2010-01-01

    Current meteor shower forecast models project a strong Draconid outburst, possibly a storm, on October 8, 2011, with a duration of approximately 7 hours and peaking between 19 and 21 hours UT. Predicted rates span an order of magnitude, with maximum Zenithal Hourly Rates (ZHRs) ranging from a few tens to several hundred. Calibration of the NASA MSFC Meteoroid Stream Model 1 to radar and optical observations of past apparitions, particularly the 2005 Draconid outburst 2, suggest that the maximum rate will be several hundreds per hour. Given the high spatial density of the Draconid stream, this implies a maximum meteoroid flux of 5-10 Draconids km(exp -2)/hr (to a limiting diameter of 1 mm), some 25-50 times greater than the normal sporadic flux of 0.2 km(exp -2)/ hr for particles of this size. Total outburst fluence, assuming a maximum ZHR of 750, is 15.5 Draconids km(exp -2), resulting in an overall 10x risk increase to spacecraft surfaces vulnerable to hypervelocity impacts by 1 mm particles. It is now established that a significant fraction of spacecraft anomalies produced by shower meteoroids (e.g. OLYMPUS and LandSat 5) are caused by electrostatic discharges produced by meteoroid impacts. In these cases, the charge generated is roughly proportional to v(exp 3.5(4)), giving a Draconid moving at 20 km/s approximately 1/80th the electrical damage potential of a Leonid of the same mass. In other words, a Draconid outburst with a maximum ZHR of 800 presents the same electrical risk as a normal Leonid shower with a ZHR of 15, assuming the mass indices and shower durations are the same. This is supported by the fact that no spacecraft electrical anomalies were reported during the strong Draconid outbursts of 1985 and 1998. However, the lack of past anomalies should not be taken as carte blanche for satellite operators to ignore the 2011 Draconids, as the upcoming outburst will constitute a period of enhanced risk for vehicles in near-Earth space. Each spacecrft is

  6. Practical Meteor Stream Forecasting

    NASA Technical Reports Server (NTRS)

    Cooke, William J.; Suggs, Robert M.

    2003-01-01

    Inspired by the recent Leonid meteor storms, researchers have made great strides in our ability to predict enhanced meteor activity. However, the necessary calibration of the meteor stream models with Earth-based ZHRs (Zenith Hourly Rates) has placed emphasis on the terran observer and meteor activity predictions are published in such a manner to reflect this emphasis. As a consequence, many predictions are often unusable by the satellite community, which has the most at stake and the greatest interest in meteor forecasting. This paper suggests that stream modelers need to pay more attention to the needs of this community and publish not just durations and times of maxima for Earth, but everything needed to characterize the meteor stream in and out of the plane of the ecliptic, which, at a minimum, consists of the location of maximum stream density (ZHR) and the functional form of the density decay with distance from this point. It is also suggested that some of the terminology associated with meteor showers may need to be more strictly defined in order to eliminate the perception of crying wolf by meteor scientists. An outburst is especially problematic, as it usually denotes an enhancement by a factor of 2 or more to researchers, but conveys the notion of a sky filled with meteors to satellite operators and the public. Experience has also taught that predicted ZHRs often lead to public disappointment, as these values vastly overestimate what is seen.

  7. Double laminar and turbulent meteor trails observed in space and simulated in the laboratory

    NASA Astrophysics Data System (ADS)

    Kelley, M. C.; Williamson, C. H. K.; Vlasov, M. N.

    2013-06-01

    One of nature's most interesting and beautiful sights is meteor trails that are visible to the naked eye. The first published sketches of trails appeared in 1869 after the Leonids storm of 1868. One of the perplexing features of these trails is that very often they are double trails and seldom triple or quadruple, which rules out breaking up or fractioning as a source. The original observations were visual and reproduced in artwork. The photographs used now reveal the accuracy of the original 1868 drawings. Since 1907, scientific explanations have ruled out physical breakup as a source. The long-standing explanation by Trowbridge (1907) has also been ruled out using modern cameras, and several new explanations have been proposed. Here we modify the explanation by Zinn and Drummond (2005), who modeled the event as an explosion followed by buoyancy, and instead, explain the effect by showing that the trails are severely convectively unstable, leading to the vortices proposed by these authors. This idea is supported by lidar-based measurements of the temperature gradient in the trail. We also show laboratory experiments that are remarkably similar to the meteor trails in appearance, although we argue that buoyancy is not the effect in the natural case.

  8. SPA Meteor Section Results: 2008

    NASA Astrophysics Data System (ADS)

    McBeath, Alastair

    2013-10-01

    A report based on meteor data analyses from 2008 performed by the SPA Meteor Section is given with some discussion. Items detailed comprise: the Quadrantid peak on January 4 which may have had an unusual dip in activity partway through; the Perseid maximum, which seemed to produce two peaks, by far the strongest-recorded of which was around 02h UT on August 13; a meteor outburst on September 9 probably due to the September epsilon-Perseids, for which the radio results suggested activity was present at a stronger level for longer than previous visual and video findings had supposed, perhaps with more than one maximum; another stronger than expected return from the Orionids during October, part of the sequence of unusual events begun in 2006; a fresh Taurid ``swarm'' return in late October to early November, which probably produced somewhat higher activity than normal, if without the increased bright-meteor component observed at some previous returns; strong Leonid activity later in November, from the radio reports, possibly with two peaks; a Geminid maximum in December which showed some curious discrepancies between the limited visual and radio observations; and the Ursids, which may have provided another moderately-enhanced return, with up to four potential peaks recorded by radio observations in the first twelve hours UT of December 22.

  9. The Lunar Atmosphere as a Cosmic-Ray Detector

    NASA Technical Reports Server (NTRS)

    Wilson, T. L.

    2007-01-01

    The recent discovery of a tenuous sodium (Na) atmosphere on the Moon and Mercury has renewed interest in studying the lunar atmosphere since the physics involved for the two bodies is thought to be of similar nature. Na came as a surprise because it had been missed by in situ UV measurements made during the Apollo program. The new lunar observations involve the visible D1 (5896 ) and D2 (5890 ) wavelengths which are highly efficient at scattering sunlight. Although its lunar source and morphology is still not completely understood, Na is present as a collisionless exosphere - apparently in the form of a cometary-type coma with a tail that can extend hundreds of lunar radii during Leonid showers. The global shape of the atmosphere, in particular for the shaded antisolar side, has been modelled by Smyth. Since planetary atmospheres can be used as cosmic-ray (CR) spectrometers by means of their fluorescence excited by CR-induced air shower particles, the subject of the Moon s atmosphere as a CR detector will be discussed here.

  10. The activity of autumn meteor showers in 2006-2008

    NASA Astrophysics Data System (ADS)

    Kartashova, Anna

    2015-03-01

    The purpose of meteor observations in INASAN is the study of meteor showers, as the elements of the migrant substance of the Solar System, and estimation of risk of hazardous collisions of spacecrafts with the particles of streams. Therefore we need to analyze the meteor events with brightness of up to 8 m, which stay in meteoroid streams for a long time and can be a hazardous for the spacecraft. The results of our single station TV observations of autumn meteor showers for the period from 2006 to 2008 are presented. The high-sensitive hybrid camera (the system with coupled of the Image Intensifier) FAVOR with limiting magnitude for meteors about 9m. . .10m in the field of view 20 × 18 was used for observations. In 2006-2008 from October to November more than 3 thousand of meteors were detected, 65% from them have the brightness from 6m to 9m. The identification with autumn meteor showers (Orionids, Taurids, Draconids, Leonids) was carried out. In order to estimate the density of the influx of meteor matter to the Earth for these meteor showers the Index of meteor activity (IMA) was calculated. The IMA distribution for the period 2006 - 2008 is given. The distributions of autumn meteor showers (the meteors with brightness of up to 8 m) by stellar magnitude from 2006 to 2008 are also presented.

  11. Luminous Efficiency of Hypervelocity Meteoroid Impacts on the Moon Derived from the 2006 Geminids, 2007 Lyrids, and 2008 Taurids

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Suggs, R. M.; Swift, W. R.; Suggs, R. J.; Cooke, W. J.; Diekmann, A. M.; McNamara, H.

    2010-01-01

    Since early 2006 the Meteoroid Environment Office at NASA's Marshall Space Flight Center has been consistently monitoring the Moon for impact flashes produced by meteoroids striking the lunar surface. During this time, several meteor showers have produced multiple impact flashes on the Moon. The 2006 Geminids, 2007 Lyrids, and 2008 Taurids were observed with average rates of 5.5, 1.2, and 1.5 meteors/hr, respectively, for a total of 12 Geminid, 11 Lyrid, and 12 Taurid lunar impacts. These showers produced a sufficient, albeit small sample of impact flashes with which to perform a luminous efficiency analysis similar to that outlined in Bellot Rubio et al. for the 1999 Leonids. An analysis of the Geminid, Lyrid, and Taurid lunar impacts is carried out herein in order to determine the luminous efficiency in the 400-900 nm wavelength range for each shower. Using the luminous efficiency, the kinetic energies and masses of these lunar impactors can be calculated.

  12. Orbits and emission spectra from the 2014 Camelopardalids

    NASA Astrophysics Data System (ADS)

    Madiedo, José M.; Trigo-Rodríguez, Josep M.; Zamorano, Jaime; Izquierdo, Jaime; de Miguel, Alejandro Sánchez; Ocaña, Francisco; Ortiz, José L.; Espartero, Francisco; Morillas, Lorenzo G.; Cardeñosa, David; Moreno-Ibáñez, Manuel; Urzáiz, Marta

    2014-12-01

    We have analysed the meteor activity associated with meteoroids of fresh dust trails of Comet 209P/LINEAR, which produced an outburst of the Camelopardalid meteor shower (IAU code #451, CAM) in 2014 May. With this aim, we have employed an array of high-sensitivity CCD video devices and spectrographs deployed at 10 meteor observing stations in Spain in the framework of the Spanish Meteor Network. Additional meteoroid flux data were obtained by means of two forward-scatter radio systems. The observed peak zenithal hourly rate was much lower than expected, of around 20 meteors h-1. Despite of the small meteor flux in the optical range, we have obtained precise atmospheric trajectory, radiant and orbital information for 11 meteor and fireball events associated with this stream. The ablation behaviour and low tensile strength calculated for these particles reveal that Camelopardalid meteoroids are very fragile, mostly pristine aggregates with strength similar to that of the Orionids and the Leonids. The mineral grains seem to be glued together by a volatile phase. We also present and discuss two unique emission spectra produced by two Camelopardalid bright meteors. These suggest a non-chondritic nature for these particles, which exhibit Fe depletion in their composition.

  13. On the record in the night of April 5, 687B.C.: stars were not seen and stars fell like rain at midnight

    NASA Astrophysics Data System (ADS)

    Zhuang, T. S.

    2006-01-01

    A long time insoluble mystery is why the night stars were not seen; in a paragraph recorded in Chun Qiu which was one night during the ``Xin Mao'' in April in the seventh year of Lu Zhuang-gong (687.B.C) in night, the stars were not seen and in midnight the stars fell like rain. '' Historically, most of the scholars had considered that ``stars not seen '' and ``stars fell like rain ''as two phenomena not related. On the basis of the brightness in the sky when Leonids appeared in 1533 researched in 1994, collating the relative date ancient and modern, Chinese and foreign, the author found the reason that the stars were not seen in fact was the brightness in sky given by meteor shower. The phenomenon that the stars were not seen and the stars fell like rain at the same period, in midnight are proved concisely. The density of the meteor shower appeared, the sum total of the meteor, the mass of the meteor eclipsing the light of the stars and the area of the concealed stars are also estimated.

  14. Micrometeor Observations Using the Arecibo 430 MHz Radar. I. Determination of the Ballistic Parameter from Measured Doppler Velocity and Deceleration Results

    NASA Astrophysics Data System (ADS)

    Janches, D.; Mathews, J. D.; Meisel, D. D.; Zhou, Q.-H.

    2000-05-01

    We present a sample of radar meteors detected during the November 1997 Leonids shower period using the narrow-beam, high-power Arecibo Observatory 430-MHz radar. During this period ˜7700 events were detected over 73 h of observations that included six mornings. Near apex-crossing, 6-10 events per minute were observed in the ˜300-m diameter beam. From these events a total of 390 meteors are characterized by a clear linear deceleration as derived from the radial Doppler speed determined from the meteor-echo leading-edge (head-echo). We interpret our results in terms of the meteor ballistic parameter—the ratio of the meteoroid mass to cross-sectional area—yielding a physical characterization of these particles prior to any assumptions regarding meteoroid shape and mass density. In addition, we compare these measurements with the results of a numerical solution of the meteor deceleration equation and find them in good agreement. The size and dynamical mass of the meteoroids are estimated considering these particles to be spheres with densities of 3 g/cm 3. We also discuss atmospheric energy-loss mechanisms of these meteroids. We believe these are the first radar meteor decelerations detected since those ones reported by J. V. Evans (1966, J. Geophys. Res. 71, 171-188) and F. Verniani (1966, J. Geophys. Res. 71, 2749-2761; 1973, J. Geophys. Res. 78, 8429-8462) and the first ones for meteors of this size.

  15. Modulational excitation of low-frequency dust acoustic waves in the Earth's lower ionosphere

    SciTech Connect

    Kopnin, S. I.; Popel, S. I.; Yu, M. Y.

    2007-04-15

    During the observation of Perseid, Leonid, Gemenid, and Orionid meteor showers, stable low-frequency lines in the frequency range of 20-60 Hz were recorded against the radio-frequency noise background. A physical mechanism for this effect is proposed, and it is established that the effect itself is related to the modulational interaction between electromagnetic and dust acoustic waves. The dynamics of the components of a complex (dusty) ionospheric plasma with dust produced from the evolution of meteoric material is described. The conditions for the existence of dust acoustic waves in the ionosphere are considered, and the waves are shown to dissipate energy mainly in collisions of neutral particles with charged dust grains. The modulational instability of electromagnetic waves in a complex (dusty) ionospheric plasma is analyzed and is found to be driven by the nonlinear Joule heating, the ponderomotive force, and the processes governing dust charging and dynamics. The conditions for the onset of the modulational instability of electromagnetic waves, as well as its growth rate and threshold, are determined for both daytime and nighttime. It is shown that low-frequency perturbations generated in the modulational interaction are related to dust acoustic waves.

  16. Damping in the growth of plasma irregularities caused by meteoric dust particles in the equatorial E-region

    NASA Astrophysics Data System (ADS)

    Muralikrishna, Polinaya

    2016-07-01

    Two stream and gradient drift instability mechanisms operating in the E-region of the equatorial ionosphere can be affected by dust particles of meteoric origin. The dust particles can capture the ambient electrons and cause considerable increase in the loss rate of electrons thus affecting the growth rates and amplitudes of the plasma irregularities. The attachment of electrons on dust particles can increase the threshold velocities needed for the onset of two stream and gradient drift instability mechanisms responsible for the generation of Type I and Type II plasma irregularities respectively, observed in the equatorial E-region plasma. Also from simple theoretical considerations one can see that the growth rate and amplitude of both Type I and Type II irregularities can be reduced considerably by the meteoric dust particles by increasing the collision frequencies. Observation of persistence of Leonid meteor trails is probably due to the reduction in the wave amplitudes and their dependent diffusion rate caused by the electron bite outs produced by the ambient dust particles. In situ rocket observations also indicate that, under similar ambient conditions, the amplitudes of Type II irregularities observed in the lower E-region are considerably smaller than those observed at higher altitudes. This probably is a direct evidence for the effect of dust particles that dominate the lower E-region altitudes practically all the time.

  17. Physics at the Moscow State University in 70-th. Photographs

    NASA Astrophysics Data System (ADS)

    Gaina, Alex B.; Perov, Nikolay S.

    The Internet proceeding contains various photographs and autographs of scientists from the Moscow State University, made during 70-th and 80-th years of XX-th Century. While no the album refers to Physics in totality, the main part of the album does refer. It includes photographs and autographs of the Members of the Academy of Sciences of U.S.S.R. Il'ya M. Lifshitz, Alexander I. Ishlinskii, Leonid V. Keldysh, Nobel Prize Winners Vitaly L. Ginzburg and Andrej D. Sakharov, Professors: I.M. Ternov, M.I. Kaganov, V.I. Grigor'ev, V.R. Khalilov, V.Ch. Zhukovskij, V.G. Bagrov (Tomsk State University) and other. Another part of peoples on the photographs became later University professors and Members of Academies. A photo concerns the graduated from the Moscow University, astronomer Vladimir A. Albitzky (1892-1952) made in Odessa during the First World War, while another concerns the School "Quantum Particles in intense fields" held in Chisinau in May 1985.

  18. Luminous Efficiency of Hypervelocity Meteoroid Impacts on the Moon Derived from the 2006 Geminids, 2007 Lyrids, and 2008 Taurids

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Suggs, R. M.; Swift, W. R.; Suggs, R. J.; Cooke, W. J.; Diekmann, A. M.; Koehler, H. M.

    2010-01-01

    Since early 2006 the Meteoroid Environment Office (MEO) at NASA s Marshall Space Flight Center has been consistently monitoring the Moon for impact flashes produced by meteoroids striking the lunar surface. During this time, several meteor showers have produced multiple impact flashes on the Moon. The 2006 Geminids, 2007 Lyrids, and 2008 Taurids were observed with average rates of 5.5, 1.2, and 1.5 meteors/hr, respectively, for a total of 12 Geminid, 12 Lyrid, and 12 Taurid lunar impacts. These showers produced a sufficient, albeit small sample of impact flashes with which to perform a luminous efficiency analysis similar to that outlined in Bellot Rubio et al. (2000) for the 1999 Leonids. An analysis of the Geminid, Lyrid, and Taurid lunar impacts is carried out herein in order to determine the luminous efficiency in the 400-800 nm wavelength range for each shower. Using the luminous efficiency, the kinetic energies and masses of these lunar impactors can be calculated.

  19. History of dermatologic surgery. From the beginnings to late antiquity.

    PubMed

    Marmelzat, W L

    1987-01-01

    We stop short, with Celsus, our glimpse of ancient dermatologic surgery in the West. As was stated at the beginning of the chapter, only a few examples and speculations are mentioned in this brief account. Much has gone unmentioned, including the contributions of great Eastern civilizations, such as ancient India, China, and Persia; the Bible; and the "ancient" inhabitants of the "new" world. We note especially the omission of the amazing ancient Hindu cosmetic operations that successfully employed rotating pedicle flaps in reconstructing amputated ears and noses. Important names before Celsus are missing from this account, especially the two Alexandrian physician-surgeons who flourished three centuries earlier--Herophilus (the Father of Anatomy) and Erasistratus (the Father of Physiology). Except for a few extant anatomic fragments, the works of Herophilus and Erasistratus are completely lost. We may with confidence, however, infer from the writings of Celsus and Galen that the brillant anatomy and physiology of the Alexandrian period made for good surgical diagnosis and practice. We must remember, too, that after Celsus' time, the slow disintergration of the Roman Empire took more than 500 years. This period of 500 years saw a number of important Roman physician-surgeons who contributed significantly with daring new operations and original surgical concepts and techniques: Heliodorus, Soranus, Rufus, Archigenes, Galen, Antyllus, Leonides, Oribasius, Aetius, Paulus, and others. The positive surgical contributions of these giants would be lost and rediscovered, many times. PMID:3328643

  20. Major safety provisions in nuclear-powered ships

    SciTech Connect

    Khlopkin, N.S.; Belyaev, V.M.; Dubrovin, A.M.; Mel'nikov, E.M.; Pologikh, B.G.; Samoilov, O.B.

    1984-12-01

    Considerable experience has been accumulated in the Soviet Union on the design, construction and operation of nuclear-powered civilian ships: the icebreakers Lenin, Leonid Brezhnev and Sibir. The nuclear steam plants (NSP) used on these as the main energy source have been found to be highly reliable and safe, and it is desirable to use them in the future not only in icebreakers but also in transport ships for use in ice fields. The Soviet program for building and developing nuclear-powered ships has involved careful attention to safety in ships containing NSP. The experience with the design and operation of nuclear icebreakers in recent years has led to the revision of safety standards for the nuclear ships and correspondingly ship NSP and international guidelines have been developed. If one meets the requirements as set forth in these documents, one has a safe basis for future Soviet nuclear-powered ships. The primary safety provisions for NSP are presented in this paper.

  1. Recent Advances in Video Meteor Photometry

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.; Meachem, Terry; Cooke, William J.

    2003-01-01

    One of the most common (and obvious) problems with video meteor data involves the saturation of the output signal produced by bright meteors, resulting in the elimination of such meteors from photometric determinations. It is important to realize that a "bright" meteor recorded by intensified meteor camera is not what would be considered "bright" by a visual observer - indeed, many Generation II or III camera systems are saturated by meteors with a visual magnitude of 3, barely even noticeable to the untrained eye. As the relatively small fields of view (approx.30 ) of the camera systems captures at best modest numbers of meteors, even during storm peaks, the loss of meteors brighter than +3 renders the determination of shower population indices from video observations even more difficult. Considerable effort has been devoted by the authors to the study of the meteor camera systems employed during the Marshall Space Flight Center s Leonid ground-based campaigns, and a calibration scheme has been devised which can extend the useful dynamic range of such systems by approximately 4 magnitudes. The calibration setup involves only simple equipment, available to amateur and professional, and it is hoped that use of this technique will make for better meteor photometry, and move video meteor analysis beyond the realm of simple counts.

  2. Remembering AB

    NASA Astrophysics Data System (ADS)

    Belyayev, S. T.

    2013-06-01

    In 1947 I became a second-year student at Moscow State University's Physics and Engineering Department, where a part of the week's classes were taught at base organizations. Our group's base was the future Kurchatov Institute, at that time known as the mysterious "Laboratory N^circ 2," and later as LIPAN. . Besides group lectures and practical work at the experimental laboratories, we also had access to the general seminars which Igor Vasilyevich Kurchatov tried to hold, with Leonid Vasilyevich Groshev filling in when he was absent. At the seminar, theorists spoke as welcome co-presenters and commentators. In 1949 I felt ready to approach A. B. Migdal to ask if I could transfer to his theoretical sector. In response, he suggested a number of simple qualitative problems, which I then successfully solved. (Incidentally, AB used the very same "introductory problems" for screening many generations of students.) So I wound up among AB's students. From 1952 on (for 10 years) I also served as an employee of the Migdal Sector. My memoirs here are mainly inspired by these years of constant communication with AB. After my departure for Novosibirsk in 1962, although our meetings still took place, they became occasional....

  3. Optical Pattern Recognition

    NASA Astrophysics Data System (ADS)

    Yu, Francis T. S.; Jutamulia, Suganda

    2008-10-01

    Contributors; Preface; 1. Pattern recognition with optics Francis T. S. Yu and Don A. Gregory; 2. Hybrid neural networks for nonlinear pattern recognition Taiwei Lu; 3. Wavelets, optics, and pattern recognition Yao Li and Yunglong Sheng; 4. Applications of the fractional Fourier transform to optical pattern recognition David Mendlovic, Zeev Zalesky and Haldum M. Oxaktas; 5. Optical implementation of mathematical morphology Tien-Hsin Chao; 6. Nonlinear optical correlators with improved discrimination capability for object location and recognition Leonid P. Yaroslavsky; 7. Distortion-invariant quadratic filters Gregory Gheen; 8. Composite filter synthesis as applied to pattern recognition Shizhou Yin and Guowen Lu; 9. Iterative procedures in electro-optical pattern recognition Joseph Shamir; 10. Optoelectronic hybrid system for three-dimensional object pattern recognition Guoguang Mu, Mingzhe Lu and Ying Sun; 11. Applications of photrefractive devices in optical pattern recognition Ziangyang Yang; 12. Optical pattern recognition with microlasers Eung-Gi Paek; 13. Optical properties and applications of bacteriorhodopsin Q. Wang Song and Yu-He Zhang; 14. Liquid-crystal spatial light modulators Aris Tanone and Suganda Jutamulia; 15. Representations of fully complex functions on real-time spatial light modulators Robert W. Cohn and Laurence G. Hassbrook; Index.

  4. Dynamical systems theory and applications

    NASA Astrophysics Data System (ADS)

    Awrejcewicz, Jan

    2006-08-01

    The 7th International Conference devoted to "Dynamical Systems-Theory and Applications" hold in 8-11 December, 2003 in Łódź, Poland, and it was organized by the staff of Department of Automatics and Biomechanics of the Technical University of Łódź. It was financially supported by the Rector of the Technical University of Łódź and the Department of Education and Physical Culture of the Łódź City Hall. The members of the International Scientific Committee included: Igor V. Andrianov (Dniepropetrovsk), Jan Awrejcewicz (Łódź), Iliya Blekhman (Sankt Petersburg), Roman Bogacz (Warszawa), Dick van Campen (Eindhoven), Zbigniew Engel (Kraków), Lothar Gaul (Stuttgart), Józef Giergiel (Kraków), Michał Kleiber (Warszawa), Vadim A. Krysko (Saratov), Włodzimierz Kurnik (Warszawa), Claude-Henri Lamarque (Lyon), Leonid I. Manevitch (Moscow), Jan Osiecki (Warszawa), Wiesaw Ostachowicz (Gdańsk), Ladislav Pust (Prague), Giuseppe Rega (Rome), Tsuneo Someya (Tokyo), Zbigniew Starczewski (Warszawa), Eugeniusz Świtoński (Gliwice), Andrzej Tylikowski (Warszawa), Tadeusz Uhl (Kraków), Aleksander F. Vakakis (Illinois), Józef Wojnarowski (Gliwice).

  5. American Zodiac: Astronomical signs in Dickinson, Melville, and Poe

    NASA Astrophysics Data System (ADS)

    Ricca, Bradley James

    2003-11-01

    Science and literature, two means of inquiry now thought in opposition (if not posed as outright contradiction) emerged for a moment in the nineteenth century as provocatively complimentary in their methods of reading. In America, astronomy in particular provided a rich, complex subject for writers of the imagination to think about in terms of content and methodology. The purpose of my study is to uncover these unacknowledged astronomical referents in the works of Emily Dickinson, Herman Melville, and Edgar Allan Poe, and engage them as interpretive contexts in new readings of their most esoteric projects; specifically, Dickinson's solstice and circumference poetry, the Plinlimmon pamphlet in Melville's Pierre, and Poe's Eureka. After providing historical context through the shared public experience of the 1833 Leonid Meteor Storm, I uncover several astronomical and scientific sources for these writers: Denison Olmsted for Dickinson; Gauss and Plotinus for Melville; and Kepler and Alexander von Humboldt for Poe, among others. Exploring these sources in close readings of their works, I find that these authors employ astronomical facts in very different, metaphorical ways in response to the larger challenge of navigating their own poetics between the emerging new laws of science and the immeasurability of human feeling evoked by the unknown Universe.

  6. Meteoroid mass determination using head echoes detected at multiple frequencies

    NASA Astrophysics Data System (ADS)

    Close, Sigrid; Oppenheim, Meers; Hunt, Stephen; McKeen, Fred; Coster, Anthea

    2002-11-01

    Meteor data collected at the Kwajalein Missile Range (KMR) during the peak of the 1998 Leonid storm comprise the only simultaneous data collection of meteor head echoes and trails using seven frequencies (VHF, UHF, L-, S-, C-, Ka- and W-band). The primary sensor was the ALTAIR radar operating at 160 MHz with 30-m range resolution and 422 MHz with 7.5-m range resolution, which has both interferometric and polarization capabilities. This paper presents an alaysis of these high-resolution data in support of the following ideas: First, head echo scattering appears to arise from an ionized region with a density sufficiently high that its plasma frequency exceeds the radar frequency (overdense reflection). Second, the Radar-cross-section (RCS) values, which decrease with decreasing wavelength, peak near 105 km altitude at the point where the meteoroid gives up the most kinetic energy during its descent. Third, these RCS measurements were used to compute electron line densities, which provide estimates of a meteoroid's mass. By combining these data and simple ablation models, we can constrain meteoroid mass as it loses material during its passage through the atmosphere.

  7. Hazards by meteoroid Impacts onto operational spacecraft

    NASA Astrophysics Data System (ADS)

    Landgraf, M.; Jehn, R.; Flury, W.

    Operational spacecraft in Earth orbit or on interplanetary trajectories are exposed to high-velocity particles that can cause damage to sensitive on-board instrumentation. In general there are two types of hazard: direct destruction of functional elements by impacts, and indirect disturbance of instruments by the generated impact plasma. The latter poses a threat especially for high-voltage instrumentation and electronics. While most meteoroids have sizes in the order of a few micrometre, and typical masses of 10-15 kg, the most dangerous population with sizes in the millimetre and masses in the milligramme range exhibits still substantial impact fluxes in the order of 2 × 10-11 m-2 s-1 . This level of activity can by significantly elevated during passages of the spacecraft through cometary trails, which on Earth cause events like the well-known Leonid and Perseid meteor streams. The total mass flux of micrometeoroids onto Earth is about 107 kg yr-1 , which is about one order of magnitude less than the estimated mass flux of large objects like comets and asteroids with individual masses above 105 kg. In order to protect spacecraft from the advert effects of meteoroid impacts, ESA performs safety operations on its spacecraft during meteor streams, supported by real-time measurements of the meteor activity. A summary of past and future activities is given.

  8. Luminous Efficiency of Hypervelocity Meteoroid Impacts on the Moon Derived from the 2006 Geminids, 2007 Lyrids, and 2008 Taurids

    NASA Technical Reports Server (NTRS)

    Moser, D. E.; Suggs, R. M.; Swift, W. R.; Suggs, R. J.; Cooke, W. J.; Diekmann, A. M.; Koehler, H. M.

    2011-01-01

    Since early 2006, NASA s Marshall Space Flight Center has been routinely monitoring the Moon for impact flashes produced by meteoroids striking the lunar surface. During this time, several meteor showers have produced multiple impact flashes on the Moon. The 2006 Geminids, 2007 Lyrids, and 2008 Taurids were observed with average rates of 5.5, 1.2, and 1.5 meteors/hr, respectively, for a total of 12 Geminid, 12 Lyrid, and 12 Taurid lunar impacts. These showers produced a sufficient, albeit small sample of impact flashes with which to perform a luminous efficiency analysis similar to that outlined in Bellot Rubio et al. (2000a, b) for the 1999 Leonids. An analysis of the Geminid, Lyrid, and Taurid lunar impacts is carried out herein in order to determine the luminous efficiency in the 400-800 nm wavelength range for each shower. Using the luminous efficiency, the kinetic energies and masses of these lunar impactors can be calculated from the observed flash intensity.

  9. Meteors: A Delivery Mechanism of Organic Matter to The Early Earth

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Wilson, Mike A.; Packan, Dennis; Laux, Christophe O.; Krueger, Charles H.; Boyd, Iain, D.; Popova, Olga P.; Fonda, Mark; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    All potential exogenous pre-biotic matter arrived to Earth by ways of our atmosphere, where much material was ablated during a luminous phase called 1. meteors" in rarefied flows of high (up to 270) Mach number. The recent Leonid showers offered a first glimpse into the elusive physical conditions of the ablation process and atmospheric chemistry associated with high-speed meteors. Molecular emissions were detected that trace a meteor's brilliant light to a 4,300 K warm wake rather than to the meteor's head. A new theoretical approach using the direct simulation by Monte Carlo technique identified the source-region and demonstrated that the ablation process is critical in the heating of the meteor's wake. In the head of the meteor, organic carbon appears to survive flash heating and rapid cooling. The temperatures in the wake of the meteor are just right for dissociation of CO and the formation of more complex organic compounds. The resulting materials could account for the bulk of pre-biotic organic carbon on the early Earth at the time of the origin of life.

  10. STS-87 crew greet VIPs after successful landing at KSC

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Commander Kevin Kregel, center, shakes hands with the deputy director general of the National Space Agency of Ukraine (NSAU), Eduard Kuznetsov, at far right. Next to Kuznetsov is the Honorable Yuri Shcherbak, Ukraine's ambassador to the United States, standing with the president of the National Space Development Agency (NASDA) of Japan, Isao Uchida, and NASA Administrator Daniel Goldin (center). Approaching the VIPs from the left of the photo are Mission Specialists Kalpana Chawla, Ph.D., and Takao Doi, Ph.D., of NASDA. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, at KSC's Shuttle Landing Facility Runway 33, drawing the 15-day, 16- hour and 34-minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Pilot Steven Lindsey; Mission Specialist Winston Scott; and Payload Specialist Leonid Kadenyuk of NSAU. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  11. STS-87 crew participate in TCDT activities

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of the STS-87 mission, scheduled for launch Nov. 19 aboard the Space Shuttle Columbia from Pad 39B at Kennedy Space Center (KSC), participates in the Terminal Countdown Demonstration Test (TCDT) at KSC. Getting a look at the Space Shuttle Columbia are, from left, Commander Kevin Kregel; Pilot Steven Lindsey; Mission Specialist Kalpana Chawla, Ph.D.; Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine (NSAU); Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Kadenyuks back-up, Yaroslav Pustovyi, Ph.D., also of NSAU; and Mission Specialist Winston Scott. The TCDT is held at KSC prior to each Space Shuttle flight providing the crew of each mission opportunities to participate in simulated countdown activities. The TCDT ends with a mock launch countdown culminating in a simulated main engine cut-off. The crew also spends time undergoing emergency egress training exercises at the pad and has an opportunity to view and inspect the payloads in the orbiter's payload bay.

  12. STS-87 crew pose in front of the orbiter Columbia after landing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The STS-87 crew pose in front of the orbiter Columbia shortly after landing on Runway 33 at KSC's Shuttle Landing Facility. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, drawing the 15-day, 16-hour and 34- minute-long mission of 6.5 million miles to a close. From left to right are Mission Specialists Winston Scott and Takao Doi, Ph.D., of the National Space Development Agency of Japan; Commander Kevin Kregel; Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; Mission Specialist Kalpana Chawla, Ph.D.; and Pilot Steven Lindsey. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  13. NASDA President Isao Uchida shakes hands with STS-87 Mission Specialist Takao Doi, Ph.D., after land

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The president of the National Space Development Agency (NASDA) of Japan, Isao Uchida, at left, shakes hands with STS-87 Mission Specialist Takao Doi, Ph.D., of NASDA, shortly after the landing of Columbia at Kennedy Space Center. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, at KSC's Shuttle Landing Facility Runway 33, drawing the 15-day, 16-hour and 34-minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Commander Kevin Kregel; Pilot Steven Lindsey; Mission Specialists Winston Scott and Kalpana Chawla, Ph.D.; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  14. STS-87 crew walkout for TCDT

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of the STS-87 mission, scheduled for launch Nov. 19 aboard the Space Shuttle Columbia from pad 39B at Kennedy Space Center (KSC), participated in the Terminal Countdown Demonstration Test (TCDT) at KSC. Simulating the walk-out from the Operations and Checkout Building before entering a van to take them to the launch pad are (left to right) Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine; Mission Specialist Kalpana Chawla, Ph.D.; Pilot Steve Lindsey; Mission Specialist Winston Scott; Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Commander Kevin Kregel. The TCDT is held at KSC prior to each Space Shuttle flight providing the crew of each mission opportunities to participate in simulated countdown activities. The TCDT ends with a mock launch countdown culminating in a simulated main engine cut-off. The crew also spends time undergoing emergency egress training exercises at the pad and has an opportunity to view and inspect the payloads in the orbiter's payload bay.

  15. STS-87 Post Flight Presentation

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The flight crew, Cmdr. Kevin R. Kregel, Pilot Steven W. Lindsey, Mission Specialists Winston E. Scott, Kalpana Chawla, and Takao Doi, and Payload Specialist Leonid K. Kadenyuk present an overview of their mission. In the first part they can be seen performing pre-launch activities such as eating the traditional breakfast, crew suit-up, and the ride out to the launch pad. Also, included are various panoramic views of the shuttle on the pad. The crew is seen being readied in the 'white room' for their mission. After the closing of the hatch and arm retraction, launch activities are shown including countdown, engine ignition, launch, and the separation of the Solid Rocket Boosters. In the second part of the video the crew turn their attention to a variety of experiments inside the Shuttle's cabin. These experiments include the processing of several samples of materials in the glovebox facility in Columbia's middeck; the experiment called PEP, which involves heating samples and then recording the mixture as it resolidifies; and the study of plant growth in space.

  16. STS-87 M.S. Takao Doi, Ph.D., of NASDA after landing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency (NASDA) of Japan greets a NASDA official shortly after the orbiter Columbia returned to KSC, touching down on Runway 33 at KSC's Shuttle Landing Facility. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, drawing the 15-day, 16-hour and 34-minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Commander Kevin Kregel; Pilot Steven Lindsey; Mission Specialists Winston Scott and Kalpana Chawla, Ph.D.; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  17. STS-87 crew in LC-39B white room during TCDT

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of the STS-87 mission, scheduled for launch Nov. 19 aboard the Space Shuttle Columbia from pad 39B at Kennedy Space Center (KSC), participates in the Terminal Countdown Demonstration Test (TCDT) at KSC. Standing, from left, Mission Specialist Winston Scott; Backup Payload Specialist Yaroslav Pustovyi, Ph.D., of the National Space Agency of Ukraine (NSAU); Payload Specialist Leonid Kadenyuk of NSAU; Pilot Steven Lindsey; Commander Kevin Kregel; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; and Mission Specialist Kalpana Chawla, Ph.D. The TCDT is held at KSC prior to each Space Shuttle flight providing the crew of each mission opportunities to participate in simulated countdown activities. The TCDT ends with a mock launch countdown culminating in a simulated main engine cut-off. The crew also spends time undergoing emergency egress training exercises at the pad and has an opportunity to view and inspect the payloads in the orbiter's payload bay.

  18. STS-87 crew in front of LC-39B during TCDT

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of the STS-87 mission, scheduled for launch Nov. 19 aboard the Space Shuttle Columbia from Pad 39B at Kennedy Space Center (KSC), poses at the pad during a break in the Terminal Countdown Demonstration Test (TCDT) at KSC. Standing in front of the Shuttle Columbia are, from left, Commander Kevin Kregel; Mission Specialist Kalpana Chawla, Ph.D.; Pilot Steven Lindsey; Mission Specialist Takao Doi, Ph.D., of the National Space Development Agency of Japan; Backup Payload Specialist Yaroslav Pustovyi, Ph.D., of the National Space Agency of Ukraine (NSAU); Payload Specialist Leonid Kadenyuk of NSAU; and Mission Specialist Winston Scott. The TCDT is held at KSC prior to each Space Shuttle flight providing the crew of each mission opportunities to participate in simulated countdown activities. The TCDT ends with a mock launch countdown culminating in a simulated main engine cut-off. The crew also spends time undergoing emergency egress training exercises at the pad and has an opportunity to view and inspect the payloads in the orbiter's payload bay.

  19. NASDA President Isao Uchida greets STS-87 Mission Specialist Takao Doi, Ph.D., after landing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The president of the National Space Development Agency (NASDA) of Japan, Isao Uchida, at left, chats with STS-87 Mission Specialist Takao Doi, Ph.D., of NASDA, shortly after the landing of Columbia at Kennedy Space Center. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, at KSC's Shuttle Landing Facility Runway 33, drawing the 15-day, 16-hour and 34- minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Commander Kevin Kregel; Pilot Steven Lindsey; Mission Specialists Winston Scott and Kalpana Chawla, Ph.D.; and Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  20. STS-87 crew and VIPs inspect the orbiter Columbia after landing

    NASA Technical Reports Server (NTRS)

    1997-01-01

    STS-87 crew members regard the tiles underneath the orbiter Columbia shortly after its return to Runway 33 at Kennedy Space Center's Shuttle Landing Facility. Pointing to the tiles is the president of the National Space Development Agency (NASDA) of Japan, Isao Uchida, who is standing next to NASA Administrator Daniel Goldin. STS-87 Commander Kevin Kregel, at right, looks on as Pilot Steve Lindsey follows behind him to continue inspecting the orbiter. STS-87 concluded its mission with a main gear touchdown at 7:20:04 a.m. EST Dec. 5, drawing the 15-day, 16-hour and 34-minute-long mission of 6.5 million miles to a close. Also onboard the orbiter were Mission Specialists Winston Scott; Kalpana Chawla, Ph.D.; and Takao Doi, Ph.D., of NASDA; along with Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine. During the 88th Space Shuttle mission, the crew performed experiments on the United States Microgravity Payload-4 and pollinated plants as part of the Collaborative Ukrainian Experiment. This was the 12th landing for Columbia at KSC and the 41st KSC landing in the history of the Space Shuttle program.

  1. STS-87 crew walkout for TCDT

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The crew of the STS-87 mission, scheduled for launch Nov. 19 aboard the Space Shuttle Columbia from pad 39B at Kennedy Space Center (KSC), participated in the Terminal Countdown Demonstration Test (TCDT) at KSC. Simulating the walk-out from the Operations and Checkout Building before entering a van to take them to the launch pad are Payload Specialist Leonid Kadenyuk of the National Space Agency of Ukraine (at back left); Pilot Steve Lindsey (back right); Mission Specialist Kalpana Chawla, Ph.D. (middle left); Mission Specialist Winston Scott (middle right); Takao Doi, Ph.D., of the National Space Development Agency of Japan (front left); and Commander Kevin Kregel. The TCDT is held at KSC prior to each Space Shuttle flight providing the crew of each mission opportunities to participate in simulated countdown activities. The TCDT ends with a mock launch countdown culminating in a simulated main engine cut-off. The crew also spends time undergoing emergency egress training exercises at the pad and has an opportunity to view and inspect the payloads in the orbiter's payload bay.

  2. STS-87 Mission Highlights Resources Tape

    NASA Technical Reports Server (NTRS)

    1998-01-01

    The STS-87 mission the flight crew, Commander Kevin R. Kregel, Pilot Steven W. Lindsey, Mission Specialists Winston E. Scott, Kalpana Chawla, and Takao Doi, and Payload Specialist Leonid K. Kadenyuk present an overview of there mission. STS-87 will fly the United States Microgravity Payload (USMP-4), the Spartan-201, the Orbital Acceleration Research Experiment (OARE), the EVA Demonstration Flight Test 5 (EDFT-05). The objective of the observations are to investigate the mechanisms causing the heating of the solar corona and the acceleration of the solar wind which originates in the corona. While flying separately in the cargo bay, the Orbital Acceleration Research Experiment (OARE) is an integral part of USMP-04. It is a highly sensitive instrument designed to acquire and record data of low-level aerodynamic acceleration along the orbiter's principal axes in the free-molecular flow regime at orbital altitudes and in the transition regime during re-entry. OARE data will support advances in space materials processing by providing measurements of the low-level, low frequency disturbance environment affecting various microgravity experiments. OARE data will also support advances in orbital drag prediction technology by increasing the understanding of the fundamental flow phenomena in the upper atmosphere.

  3. Comet outbursts and the meteor showers

    NASA Astrophysics Data System (ADS)

    Guliyev, A. S.; Kokhirova, G. I.; Poladova, U. D.

    2014-07-01

    The features of 116 comets that have shown an outbursts in their brightness, are considered in the paper. The hypothesis on that the outburst in activity of comets are caused by their passing through meteoroid streams is studied. For this purpose the orbital elements of such comets relative to the planes of motion of 68 meteor showers from Cook's catalogue are analyzed. It was found that four of the nearest and distant nodes of comet orbits relative to the planes of motion of nine meteor showers exceeds the average statistical background with confidence probability from 0.90 to 0.95, and more than 0.95, respectively. The October Draconids, Aurigids, kappa-Serpentids, delta-Draconids, sigma-Hydrids}, Coma Berenicids, Leonids, Leo Minorids, and Perseids showers are the most effective. The results of calculation show that often, the comets outbursts may be caused by collisions of comets with meteoroids under the passing through the meteoroid streams that are producing listed meteor showers as well as solar activity.

  4. Electromagnetic Properties of Impact-Generated Plasma, Vapor and Debris

    SciTech Connect

    Crawford, D.A.; Schultz, P.H.

    1998-11-02

    Plasma, vapor and debris associated with an impact or explosive event have been demonstrated in the laboratory to produce radiofrequency and optical electromagnetic emissions that can be diagnostic of the event. Such effects could potentially interfere with communications or remote sensing equipment if an impact occurred, for example, on a satellite. More seriously, impact generated plasma could end the life of a satellite by mechanisms that are not well understood and not normally taken into account in satellite design. For example, arc/discharge phenomena resulting from highly conductive plasma acting as a current path across normally shielded circuits may have contributed to the loss of the Olympus experimental communications satellite on August 11, 1993. The possibility of significant storm activity during the Leonid meteor showers of November 1998, 1999 and 2000 (impact velocity, 72 km/s) has heightened awareness of potential vulnerabilities from hypervelocity electromagnetic effects to orbital assets. The concern is justified. The amount of plasma, electrostatic charge and the magnitude of the resulting currents and electric fields scale nearly as the cube of the impact velocity. Even for microscopic Leonid impacts, the amount of plasma approaches levels that could be dangerous to spacecraft electronics. The degree of charge separation that occurs during hypervelocity impacts scales linearly with impactor mass. The resulting magnetic fields increase linearly with impactor radius and could play a significant role in our understanding of the paleomagnetism of planetary surfaces. The electromagnetic properties of plasma produced by hypervelocity impact have been exploited by researchers as a diagnostic tool, invoked to potentially explain the magnetically jumbled state of the lunar surface and blamed for the loss of the Olympus experimental communications satellite. The production of plasma in and around an impact event can lead to several effects: (1) the

  5. Observation and research for strong meteor shower and related catastrophic space weather

    NASA Astrophysics Data System (ADS)

    Ma, Y. H.; He, Y. W.; Xu, P. X.; Zhao, H. B.

    2007-07-01

    During the first international joint observation for strong meteor shower, we made multi-subject observations for Leonids and Draconids and their disaster space weather events by several methods. Combining the synthetical analysis of Leonids, Perseids and Draconids and their related data from 1957 to 2003, we sufficiently confirm that the periodic strong meteor showers can result in the formation of catastrophic space weather events. The following summing-up is confirmed basically: 1.The formation mechanism of the strong meteor shower There are meteoroids with high density and uneven distribution close the cometary nucleus, especially in the direction of opposite the Sun and backside of the nucleus. They can stretch 1-11AU along the cometary orbit and 1-5 (&sim10^3AU) cross the orbit. Therefore good displays of meteor shower (10---100 times as usual) or storms (103---104 times as usual) can occur when the Earth passes a high density meteoroid stream during the period of 3 years before and 5 years after the perihelion passage of the comet. During that period, bolides or shooting stars which are serious harmful to spaceflight security increase greatly to 3%~10%. This corrects the wrong point of view that the harmful micro-meteoroids to spaceflight security in period meteor showers are <1 g only. 2. The cosmic dust maintaining mechanism of long-life Es layer in mid-latitude area It is proved the life of Es layer increased greatly when most ions are long-life metal type ions (Fe +, Mg + ?? ) which composite coefficient is much smaller than that of molecule type ions(O2 + , NO + ?? ). The observation for about 50 years roughly approves that the blanketing frequency of Es layer (fb Es) abnormally increase in large area (>105km2) and lasting long time (>15 min) only when strong meteor shower occurred at night. It is not f, l and c type Es layer evolved from sequence Es layer. This shows that the cause of fb Es increase is that the ionosphere was bombarded by an additional

  6. Photometric Calibration of Consumer Video Cameras

    NASA Technical Reports Server (NTRS)

    Suggs, Robert; Swift, Wesley, Jr.

    2007-01-01

    Equipment and techniques have been developed to implement a method of photometric calibration of consumer video cameras for imaging of objects that are sufficiently narrow or sufficiently distant to be optically equivalent to point or line sources. Heretofore, it has been difficult to calibrate consumer video cameras, especially in cases of image saturation, because they exhibit nonlinear responses with dynamic ranges much smaller than those of scientific-grade video cameras. The present method not only takes this difficulty in stride but also makes it possible to extend effective dynamic ranges to several powers of ten beyond saturation levels. The method will likely be primarily useful in astronomical photometry. There are also potential commercial applications in medical and industrial imaging of point or line sources in the presence of saturation.This development was prompted by the need to measure brightnesses of debris in amateur video images of the breakup of the Space Shuttle Columbia. The purpose of these measurements is to use the brightness values to estimate relative masses of debris objects. In most of the images, the brightness of the main body of Columbia was found to exceed the dynamic ranges of the cameras. A similar problem arose a few years ago in the analysis of video images of Leonid meteors. The present method is a refined version of the calibration method developed to solve the Leonid calibration problem. In this method, one performs an endto- end calibration of the entire imaging system, including not only the imaging optics and imaging photodetector array but also analog tape recording and playback equipment (if used) and any frame grabber or other analog-to-digital converter (if used). To automatically incorporate the effects of nonlinearity and any other distortions into the calibration, the calibration images are processed in precisely the same manner as are the images of meteors, space-shuttle debris, or other objects that one seeks to

  7. Consequences of cell-to-cell P-glycoprotein transfer on acquired multidrug resistance in breast cancer: a cell population dynamics model

    PubMed Central

    2011-01-01

    Leonid Hanin, Anna Marciniak-Czochra and Marek Kimmel. PMID:21269489

  8. List of Organizing Committees and Conference Programme

    NASA Astrophysics Data System (ADS)

    2012-03-01

    Organizers Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH Romanian Neutron Scattering Society Sponsors Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH Comenius University in Bratislava, Slovakia Institute of Macromolecular Chemistry AS CR, Czech Republic Programme Committee Valentin Gordely (chairman)Joint Institute for Nuclear Research, Russia Heinrich StuhrmannGermany Jose TeixeiraLaboratoire Leon Brillouin, France Pavel ApelJoint Institute for Nuclear Research, Russia Pavol BalgavyComenius University in Bratislava, Slovakia Alexander BelushkinJoint Institute for Nuclear Research, Russia Georg BueldtInstitute of Structural Biology and Biophysics (ISB), Germany Leonid BulavinTaras Shevchenko National University of Kyiv, Ukraine Emil BurzoBabes-Bolyai University, Romania Vadim CherezovThe Scripps Research Institute, Department of Molecular Biology, USA Ion IonitaRomanian Society of Neutron Scattering, Romania Alexei KhokhlovMoscow State University, Russia Aziz MuzafarovInstitute of Synthetic Polymeric Materials, Russian Academy of Sciences, Russia Alexander OzerinInstitute of Synthetic Polymeric Materials, Russian Academy of Sciences, Russia Gerard PepyResearch Institute for Solid State Physics and Optics, Hungary Josef PlestilInstitute of Macromolecular Chemistry CAS, Czech Republic Aurel RadulescuJuelich Centre for Neutron Science JCNS, Germany Maria BalasoiuJoint Institute for Nuclear Research, Russia Alexander KuklinJoint Institute for Nuclear Research, Russia Local Organizing Committee Alexander Kuklin - Chairman Maria Balasoiu - Co-chairman Tatiana Murugova - Secretary Natalia Malysheva Natalia Dokalenko Julia Gorshkova Andrey Rogachev Oleksandr Ivankov Dmitry Soloviev Lilia Anghel Erhan Raul The PDF also contains the Conference Programme.

  9. Langton's flies

    NASA Astrophysics Data System (ADS)

    Dorbec, P.; Gajardo, A.

    2008-10-01

    Langton's ant is an automaton defined over a two-dimensional grid. Its movement is governed by the environment in a very simple way: it turns to the left over white vertices and to the right over black vertices. This definition only applies on a two-dimensional space. We look for generalizations of this automaton to n-dimensional lattices. Remembering the different ways through which the ant was originally defined, we consider two approaches: the first comes from physics (lattice gas) and the second from artificial life (virtual ants). Two generalizations are proposed defining two families of dynamical systems. From the physics point of view, the ant is seen as a particle and hence it has no internal state other than its velocity. From the artificial life point of view, the ant is viewed as an insect, and it has an orientation in space which we represent by an orthogonal basis. This constitutes the ant's internal state. This formulation allows us to define the ant's behaviour without drawing upon any information relative to the global system of external coordinates. Each model yields different sets of rules with distinctive behaviours. We characterize all the possible rules satisfying some basic restrictions. We found that many rules produce trajectories which are restricted to a diagonal plane and are equivalent to a version of Langton's ant over a two-dimensional grid, squared or hexagonal. In the particle model, only two of them use the whole space, and it is shown that such rules do not admit periodical trajectories. This result reinforces a previous one reported by Leonid Bunimovich, who states that 'the skeleton of any bounded trajectory cannot contain any three-dimensional polyhedron'.

  10. Optimization of Compact Array Configurations to Minimize Side-lobes for Two Cases: The LWA Phased-array Station and the New E-configuration for the EVLA

    NASA Astrophysics Data System (ADS)

    Kogan, Leonid; Owen, F.; Ott, J.; Cohen, A.

    2011-01-01

    An optimization algorithm designed by Leonid Kogan ( L. Kogan, Optimizing a Large Array Configuration to Minimize the Side lobes, IEEE Transactions on Antennas and Propagation, vol 48, NO 7, July 2000, p 1075) to minimize side-lobes in the point-spread response has been applied in the design of two new radio-interferometric arrays: (1) the most compact (E) configuration of EVLA and (2) the phased-array station for the Long Wavelength Array (LWA). Scientific programs for the EVLA's E-configuration includes galactic and Local HII, molecular gas, cosmic web, radio continum, radio lobes, SZ effect, cosmology and pulsar searches. The LWA will operate at frequencies from 10-88 MHz and will study a wide range of scientific programs including clusters of galaxies, high-redshift radio galaxies, pulsars, SNR's, extra-solar planets, solar physics and ionospheric physics. Both arrays need to be compact and to have the smallest side lobes possible. The E-configuration was designed to minimizes cost by requiring only one new railroad track in addition to the existing EVLA infrastructure. The shadowing factor achieved is reasonably good for a wide range of hour angles and declinations. The achieved side-lobe levels in the synthesized beam are no greater than 12% within the antenna primary beam for any operating VLA wavelength. For comparison, the VLA-D configuration has side-lobes near 60%. For the LWA station configuration, the sidelobes are never greater than 1.6% at any point in the sky regardless of phased direction or operating wavelength. Such small sidelobes for both arrays promise very high image fidelity for maximum scientific results.

  11. Orbital Properties of the Arecibo Micrometeoroids at Earth Interception

    NASA Astrophysics Data System (ADS)

    Janches, D.; Meisel, D. D.; Mathews, J. D.

    2001-04-01

    Using the Arecibo Observatory (AO) 430-MHz Radar we have developed a Doppler technique to measure very precise micrometeor instantaneous velocities directly from the meteor head echo. In addition, a large number of the observed meteoroids show deceleration. With the velocity, the deceleration, and the assumptions of a spherical shape and a mean micrometeoroid mass density, we have obtained estimates of in-atmosphere particle sizes. The size estimate, the MSIS model atmosphere, and the measured deceleration are used to obtain the meteor extra-atmospheric speeds, assuming these particles undergo little mass-loss prior to and during the time we detect them (Janches et al. 2000b, Icarus145, 53-63). Orbital elements at 1 AU are presented and discussed. These results have not been corrected for perturbation effects such as radiation pressure, Poynting-Robertson drag, attraction by the giant planets, and photoelectric charging effects. So far, over 7700 detections obtained during November 1997 and 3500 during the November 1998 observation campaigns have been analyzed. The observing periods included the Leonids meteor shower, but none of the orbits are recently derived from it. Out of these detections, we present details of over 1500 orbits with eccentricities less than unity. These orbits show (a) a depletion of postperihelion particles with small perihelion distance, suggesting the possibility of collisional and thermal destruction, and (b) an enhancement of particles with perihelia in the zone between Mercury and Venus. Also discussed are 40 β-meteoroids (with radii less than 0.5 μm) dynamically related to the elliptical orbit population with q<0.7 AU. We interpret the latter results on the basis of Poynting-Robertson drag and the electromagnetic resonant effects proposed by G. E. Morfill and E. Grün (1979, Planet. Space Sci.27, 1269-1282). Comparison with previous data sets indicates that most of the AO micrometeoroid orbits are well randomized and that association

  12. SURVEYING THE DYNAMIC RADIO SKY WITH THE LONG WAVELENGTH DEMONSTRATOR ARRAY

    SciTech Connect

    Lazio, T. Joseph W.; Clarke, Tracy E.; Lane, W. M.; Gross, C.; Kassim, N. E.; Hicks, B.; Polisensky, E.; Stewart, K.; Ray, P. S.; Wood, D.; York, J. A.; Kerkhoff, A.; Dalal, N. Paravastu; Cohen, A. S.; Erickson, W. C.

    2010-12-15

    This paper presents a search for radio transients at a frequency of 73.8 MHz (4 m wavelength) using the all-sky imaging capabilities of the Long Wavelength Demonstrator Array (LWDA). The LWDA was a 16-dipole phased array telescope, located on the site of the Very Large Array in New Mexico. The field of view of the individual dipoles was essentially the entire sky, and the number of dipoles was sufficiently small that a simple software correlator could be used to make all-sky images. From 2006 October to 2007 February, we conducted an all-sky transient search program, acquiring a total of 106 hr of data; the time sampling varied, being 5 minutes at the start of the program and improving to 2 minutes by the end of the program. We were able to detect solar flares, and in a special-purpose mode, radio reflections from ionized meteor trails during the 2006 Leonid meteor shower. We detected no transients originating outside of the solar system above a flux density limit of 500 Jy, equivalent to a limit of no more than about 10{sup -2} events yr{sup -1} deg{sup -2}, having a pulse energy density {approx}>1.5 x 10{sup -20} J m{sup -2} Hz{sup -1} at 73.8 MHz for pulse widths of about 300 s. This event rate is comparable to that determined from previous all-sky transient searches, but at a lower frequency than most previous all-sky searches. We believe that the LWDA illustrates how an all-sky imaging mode could be a useful operational model for low-frequency instruments such as the Low Frequency Array, the Long Wavelength Array station, the low-frequency component of the Square Kilometre Array, and potentially the Lunar Radio Array.

  13. Hydrogen emission in meteors as a potential marker for the exogenous delivery of organics and water

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Mandell, Avram M.

    2004-01-01

    We detected hydrogen Balmer-alpha (H(alpha)) emission in the spectra of bright meteors and investigated its potential use as a tracer for exogenous delivery of organic matter. We found that it is critical to observe the meteors with high enough spatial resolution to distinguish the 656.46 nm H(alpha) emission from the 657.46 nm intercombination line of neutral calcium, which was bright in the meteor afterglow. The H(alpha) line peak stayed in constant ratio to the atmospheric emissions of nitrogen during descent of the meteoroid. If all of the hydrogen originates in the Earth's atmosphere, the hydrogen atoms are expected to have been excited at T = 4400 K. In that case, we measured an H(2)O abundance in excess of 150 +/- 20 ppm at 80-90 km altitude (assuming local thermodynamic equilibrium in the air plasma). This compares with an expected <20 ppm from H(2)O in the gas phase. Alternatively, meteoric refractory organic matter (and water bound in meteoroid minerals) could have caused the observed H(alpha) emission, but only if the line is excited in a hot T approximately 10000 K plasma component that is unique to meteoric ablation vapor emissions such as Si(+). Assuming that the Si(+) lines of the Leonid spectrum would need the same hot excitation conditions, and a typical [H]/[C] = 1 in cometary refractory organics, we calculated an abundance ratio [C]/[Si] = 3.9 +/- 1.4 for the dust of comet 55P/Tempel-Tuttle. This range agreed with the value of [C]/[Si] = 4.4 measured for comet 1P/Halley dust. Unless there is 10 times more water vapor in the upper atmosphere than expected, we conclude that a significant fraction of the hydrogen atoms in the observed meteor plasma originated in the meteoroid.

  14. The FeO Nightglow

    NASA Astrophysics Data System (ADS)

    Saran, D. V.; Slanger, T. G.

    2010-12-01

    Emission from the FeO molecule is a long-sought feature of the terrestrial nightglow. Current work in analyzing data from the OSIRIS spectrometer on the Odin satellite and the sky spectra from the ESI spectrograph on the Keck II telescope demonstrate that quasi-continuous emission near 600 nm can be identified as to be from excited FeO, by comparison with laboratory spectra obtained from the reaction between Fe and O3 [West and Broida, 1975; Jenniskens et al., 2000] and meteor trains. This emission is a ubiquitous feature in astronomical sky spectra obtained both with ESI and with the UVES/VLT system in Paranal, Chile. Integrated areas of the band profile in the 560-620 nm region with ESI show that the overhead continuum intensity is 3-4 times brighter than the sodium 589 nm lines, although the FeO emission extends well beyond 620 nm, and may reach several hundred Rayleighs. The temporal behavior of the FeO emission is closely related to that of both the sodium emission and the OH Meinel bands. This is not surprising given that all three of these nightglow emissions involve reaction with ozone. The temporal behavior needs to be modeled using global emission models because of the complexities of the intermediate reactions involved in generating the emitting states of FeO, Na and OH. Acknowledgements DVS was supported by NSF Aeronomy and CEDAR postdoc fellowship award, NSF grant ATM-0924781. TGS was supported by grant ATM-0637433 from NSF Aeronomy. References Jenniskens P., Lacey M., Allan B. J., Self D. E., Plane J. M. C., 2000, FeO "Orange Arc" emission detected in optical spectrum of Leonid persistent train. Earth, Moon and Planets 82-83, 429-438 West, J. B. and Broida, H.P.,1975, Chemiluminescence and photoluminescence of diatomic iron oxide. Journal of Chemical Physics, 62, 2566-2574.

  15. Lunar and Planetary Science XXXVI, Part 6

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Contents include the following: A Model for Multiple Populations of Presolar Diamonds. Characterization of Martian North Polar Geologic Units Using Mars Odyssey THEMIS Data. Effect of Flow on the Internal Structure of the Martian North Polar Layered Deposits. Elemental Abundance Distributions in Basalt Clays and Meteorites: Is It a Biosignature? Early Results on the Saturn System from the Composite Infrared Spectrometer. NanoSIMS D/H Imaging of Isotopically Primitive Interplanetary Dust Particles. Presolar (Circumstellar and Interstellar) Phases in Renazzo: The Effects of Parent Body Processing. Catastrophic Disruption of Hydrated Targets: Implications for the Hydrated Asteroids and for the Production of Interplanetary Dust Particles. Chemical and Mineralogical Analyses of Particles from the Stratospheric Collections Coinciding with the 2002 Leonid Storm and the 2003 Comet Grigg-Skjellerup Trail Passage. An Analysis of the Solvus in the CaS-MnS System. ESA s SMART-1 Mission at the Moon: First Results, Status and Next Steps. Europa Analog Ice-splitting Measurements and Experiments with Ice-Hunveyor on the Frozen Balaton-Lake, Hungary. Chromium on Eros: Further Evidence of Ordinary Chondrite Composition. Dust Devil Tracks on Mars: Observation and Analysis from Orbit and the Surface. Spatial Variation of Methane and Other Trace Gases Detected on Mars: Interpretation with a General Circulation Model. Mars Water Ice and Carbon Dioxide Seasonal Polar Caps: GCM Modeling and Comparison with Mars Express Omega Observations. Component Separation of OMEGA Spectra with ICA. Clathrate Formation in the Near-Surface Environment of Titan. Space Weathering: A Proposed Laboratory Approach to Explaining the Sulfur Depletion on Eros. Sample Collection from Small Airless Bodies: Examination of Temperature Constraints for the TGIP. Sample Collector for the Hera Near-Earth Asteroid Sample Return Mission. A Rugged Miniature Mass-Spectrometer for Measuring Aqueous Geochemistry on Mars

  16. Hydrogen emission in meteors as a potential marker for the exogenous delivery of organics and water.

    PubMed

    Jenniskens, Peter; Mandell, Avram M

    2004-01-01

    We detected hydrogen Balmer-alpha (H(alpha)) emission in the spectra of bright meteors and investigated its potential use as a tracer for exogenous delivery of organic matter. We found that it is critical to observe the meteors with high enough spatial resolution to distinguish the 656.46 nm H(alpha) emission from the 657.46 nm intercombination line of neutral calcium, which was bright in the meteor afterglow. The H(alpha) line peak stayed in constant ratio to the atmospheric emissions of nitrogen during descent of the meteoroid. If all of the hydrogen originates in the Earth's atmosphere, the hydrogen atoms are expected to have been excited at T = 4400 K. In that case, we measured an H(2)O abundance in excess of 150 +/- 20 ppm at 80-90 km altitude (assuming local thermodynamic equilibrium in the air plasma). This compares with an expected <20 ppm from H(2)O in the gas phase. Alternatively, meteoric refractory organic matter (and water bound in meteoroid minerals) could have caused the observed H(alpha) emission, but only if the line is excited in a hot T approximately 10000 K plasma component that is unique to meteoric ablation vapor emissions such as Si(+). Assuming that the Si(+) lines of the Leonid spectrum would need the same hot excitation conditions, and a typical [H]/[C] = 1 in cometary refractory organics, we calculated an abundance ratio [C]/[Si] = 3.9 +/- 1.4 for the dust of comet 55P/Tempel-Tuttle. This range agreed with the value of [C]/[Si] = 4.4 measured for comet 1P/Halley dust. Unless there is 10 times more water vapor in the upper atmosphere than expected, we conclude that a significant fraction of the hydrogen atoms in the observed meteor plasma originated in the meteoroid. PMID:15104908

  17. On 45 Years of Space Plasma Research

    NASA Astrophysics Data System (ADS)

    Kelley, M. C.

    2011-12-01

    After 47 years of immersion in space physics, I have many stories to tell, some of which are not suitable for all audiences and will remain untold today. But after a few such tales, I will recount the most satisfying research I have done and then outline a new book I am working on entitled "The Earth's Electric Field". I also will outline five sources of electric fields: thunderstorms, motions of the atmosphere, the solar wind, the magnetosphere, and wave phenomena. The most satisfying work I have published involves proof that the Earth was hit by a comet in 1908, studies of the long-lasting meteor trail during Leonids1998/9, and results of barium/TMA releases. On the human side, the most satisfying work has been with Cornell students, both undergraduate and graduate. Although many books have been written on the Earth's magnetic field, to my knowledge, none have been written on the electric field. This is not surprising since Gauss first noted that the Earth is a giant magnet hundreds of years ago. The first evidence of an electric field in the atmosphere was provided by Ben Franklin with his kite/thunderstorm experiments. We began considering the possibility of an electric field in space about 50 years ago, using the motion of auroral patches. Then, in the 1960s, Forrest Mozer and Ulf Fahleson showed that the electric field could be measured using rockets and, eventually, satellites. Luckily, I was Forrest's second student and Ulf was in Berkeley for a year, so I was in the perfect place for a graduate student. Thus began the quest for knowledge of the Earth's electric field, which continues today.

  18. MIDAS-W: a workstation-based incoherent scatter radar data acquisition system

    NASA Astrophysics Data System (ADS)

    Holt, J. M.; Erickson, P. J.; Gorczyca, A. M.; Grydeland, T.

    2000-09-01

    workstation with the new software can be added to the network without impacting the production system. MIDAS-W has been operated in parallel with the existing MIDAS-1 system to verify that incoherent scatter measurements by the two systems agree. MIDAS-W has also been used in a high-bandwidth mode to collect data on the November, 1999, Leonid meteor shower.

  19. Physical characteristics of the meteoroids by the results of combined radar and optical observations

    NASA Astrophysics Data System (ADS)

    Mirhusen, Narziev

    This paper proposes a method determining of the light and ionization curves by the results of combined radio - TV observations meteors in 1978-1980 in Hissar Astronomical Observatory of the Institute of Astrophysics of Sciences of Tajikistan, the calculation results of photographic and radar meteoroid mass and analysis of the shape of light curves of meteors within the theory of evaporation and the theory of the quasi-continuous fragmentation. The photographic meteoroid mass from the light curve were defined: a) by the value of maximum luminescence intensity at the height hm and b) by the integration light curve. It is based on analysis of the data of the mass were obtained correction factor that takes into account the effect of fragmentation and other factors to determine the mass of meteoroids first method. Average value of the mass of meteoroids calculated by the light curve for meteors with magnitude M≤1 is 19.10-3 g, and the average value of the mass found on magnitude of the luminescence intensity at the height the maximum brightness consist 18.2.10-3 that is in satisfactory agreement. The meteoroid’s masses was calculated also radio method by value of maximum linear electron density at the height of maximum ionization (n). The framework of the classical theory and the theory quasi-continuous fragmentation, the shape of the light curves of simultaneous radio - optical meteors were analyzed. It is shown that the main mechanism of ablation 60% of simultaneous radio - optical meteors is a quasi-continuous fragmentation. The bulk density and porosity of showers and sporadic meteoroids were determined. Found that the Geminids meteoroids and δ-Aquariids have the largest bulk densities (δo = 3.6 g/cm3). A meteoroids of the showers Orionids and Leonids have the lowest bulk density (δo ≤ 0.6 g/cm3), and the highest value of the porosity (60 ≤ K ≤ 80%). The mass fragments of flow and sporadic meteoroids lie in the range of 5.10-8÷10-5g.

  20. Shooting Stars over China

    NASA Astrophysics Data System (ADS)

    Hodges, John

    International cultural exchange and education in the sciences and arts is one of the chief aims of the British Council (BC). The 1998 Leonids Meteor Shower was recognised by the BC in China as an event that would offer an opportunity, both to promote the public understanding of space science at an international level, and to encourage on-going cultural links between the United Kingdom and China. Predictions suggested that the 1998 shower, which was likely to be the most intense for more than three decades, would be best viewed in north-east Asia. The BC contracted the Orbital Mechanics Educational Network, an independent organisation that promotes space education amongst young people, to organise several activities aimed particularly at teenagers. The culmination of the project was a visit to Beijing by a party of British teenagers, to take part in meteor observation at China's Mi Yun Observatory. The paper focusses on the practicalities of organising and running such a project and reports on the achievements and shortcomings of the overall venture. It also reports on the observations and findings that were made by the UK group and their Chinese student partners, all of whom were observing a meteor shower for the first time. It reports on the techniques of observing that were tried, the observations themselves and the findings that were made by the group. It also offers advice to those who might wish to set up similar bi-lateral ventures, particularly with China and the UK, and outlines plans to continue and improve the relationships that have been established. (Please note: I realise this is topic not directly covered by the Conference, but how the subject of the meteor phenomenon in particular and, for that matter, science in general is conveyed to the " man in the street" should be important to all scientists, not least because they depend on external funding and public goodwill! Perhaps a suitable slot can be made for this presentation on Tuesday, which is the

  1. Dust Trails of SP/Tuttle and the Unusual Outbursts of the Ursid Shower

    NASA Technical Reports Server (NTRS)

    Jenniskens, Peter; Lyytinen, E.; deLignie, M. C.; Johannink, C.; Jobse, K.; Schievink, R.; Langbroek, M.; Koop, M.; Gural, P.; Wilson, M.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    Halley-type comets tend to have a series of dust trails that remain spatially correlated for extended periods of time, each dating from a specific return of the comet. Encounters with 1 - 9 revolution old individual dust trails of 55P/Tempel-Tuttle have led to well recognized Leonid shower maxim, the peak time of which was well predicted by recent models. Now. we used the same model to calculate the position of dust trails of comet Shuttle, a Halley-type comet in an (approximately) 13.6 year orbit passing just outside of Earth's orbit. We discovered that the meteoroids tend to be trapped in the 14:12 mean motion resonance with Jupiter, while the comet librates in a slightly shorter period orbit around the 13:15 resonance. It takes six centuries to change the orbit enough to intersect Earth's orbit. During that time, the meteoroids and comet separate in mean anomaly by six years. thus explaining the unusual aphelion occurrences of Ursid outbursts. The resonances also prevent dispersion, so that the dust trail encounters (specifically, from dust trails of AD 1378 - 1405) occur only in one year in each orbit. We predicted enhanced activity on December 22, 2000, at around 7:29 and 8:35 UT (universal time) from dust trails dating to the 1405 and 1392 return, respectively. This event was observed from California using video and photographic techniques. At the same time, five Global-MS-Net stations in Finland, Japan and Belgium counted meteors using forward meteor scatter. The outburst peaked at 8:06:07 UT, December 22, at Zenith Hourly Rate (approx.) 90 per hour. The Ursid rates were above half peak intensity during 4.2 hours. This is only the second Halley type comet for which a meteor outburst can be dated to a specific return of the parent comet, and traces their presence back form 9 to at least 45 revolutions of the comet. New orbital elements of Ursid meteoroids are presented. We find that most orbits do scatter around the anticipated positions, confirming the link

  2. Preface

    NASA Astrophysics Data System (ADS)

    Gurvits, L. I.; Frey, S.; Rawlings, S.

    than 30 contributed papers from that symposium have been published recently in Baltic Astronomy (2005, Vol. 14, No. 3). This book contains a set of invited review presentations given at the symposium. They cover a range of scientific topics in extragalactic and galactic radio astronomy studies as well as recent developments in radio astronomy techniques aimed at the next generation radio astronomy facilities. On behalf of the organisers and participants of the symposium, we express our gratitude to the sponsors of the event and this publication: the European Astronomical Society, Hungarian Academy of Sciences, Eötvös Loránd University, Konkoly Observatory, Eötvös Loránd Physical Society, Netherlands Foundation for Research in Astronomy (ASTRON), Joint Institute for VLBI in Europe, Hungarian Scientific Research Fund, EC FP5 Infrastructure Cooperation Network RadioNET and EC FP6 Integrated Infrastructure Initiative RadioNet. We are grateful to the members of the Scientific Organising Committee of the Symposium. Ken Kellermann made very useful remarks on several papers. Ellen Bouton and Pat Smiley helped to include in this book several photos from the AUI-NRAO archive. Mark Bentum designed the cover picture of the book, visual components for which were kindly supplied by W.A. Baan, M.F. Bietenholz, R. Boomsma, R. Braun, N. Bartel, M.A. Garrett, J.M. van der Hulst, H.R. Klockner, NASA/WMAP Science Team, T.A. Oosterloo, M.P. Rupen, R. Sancisi, B. Stappers, R.G. Strom, D.A. Thilker, and R.A.M. Walterbos. Most of all, we are grateful to all the authors of this book for their efforts in the increasingly old-fashioned art of writing papers for a real “paper” publication as opposed to putting powerpoint files on a web site. We do hope that their nice work will be appreciated by the readers. Leonid Gurvits, Dwingeloo, The Netherlands Sándor Frey, Budapest, Hungary Steve Rawlings, Oxford, UK

  3. Observations of elevated Atlantic water heat fluxes at the boundary of the Arctic Basin.

    NASA Astrophysics Data System (ADS)

    Lincoln, Benjamin; Rippeth, Tom; Lenn, Yueng; Bacon, Sheldon

    2014-05-01

    diffusive fluxes. Dissipation rates were enhanced by up to 3 orders of magnitude at the boundaries of the Arctic basin with the highest rates North of Svalbard and decreasing ɛ anticlockwise around the basin with low ɛ in the Canada basin. Enhanced heat fluxes at the boundaries ranged from 10-100 Wm-2 north of Svalbard decreasing to 2-5 Wm-2 along the Laptev shelf slope and less than 0.5 Wm-2 along the East Siberian slope and Lomonosov ridge. In the Canada basin heat fluxes at the boundary were less than 0.2 Wm-2. --- Arctic Ocean Warming Contributes to Reduced Polar Ice Cap Igor V. Polyakov, Leonid A. Timokhov, Vladimir A. Alexeev, Sheldon Bacon, Igor A. Dmitrenko, Louis Fortier, et al. in Journal of Physical Oceanography (2010)

  4. Atmospheric parameters in the mesosphere and lower thermosphere estimated using the Platteville, CO (40°N, 105°W) interferometric meteor radars

    NASA Astrophysics Data System (ADS)

    de La Pena, Santiago

    Two interferometric meteor radars operating at different frequencies have been collecting data for several years at the Platteville Atmospheric Observatory. Meteor decay rates measured by the two systems have been analyzed with the purpose of comparing estimates of the ambipolar diffusion in meteors made with the radars. Ambipolar diffusion is the main dispersion process for meteors. Due to its dependence on atmospheric conditions, it has been used in recent studies to estimate meteor height, and atmospheric temperature and pressure. The results of the comparison made shed light on the conditions under which meteor decay rates can be used to estimate ambipolar diffusion. The response of the two systems to sporadic and shower meteor activity was analyzed and discussed. The radars show similar temporal distributions of the echoes detected from meteor trails, but present some differences in the spatial distribution. The Statistics of the data collected by the radars present differences in the meteor echo spatial distribution between sporadic meteor activity and meteor shower events. Observations of a strong 2001 Leonid meteor storm were presented. A difference in the maximum altitude at which the radars detect meteors was seen. This limit in height is caused by a geophysical effect commonly known as meteor echo ceiling. Six years of horizontal wind estimates near the mesopause obtained from the meteor radars have been analyzed with the objective of studying the spatial and seasonal variability of the main tidal components identified in the wind structure. Interferometric capabilities allowed the estimation of the location of the detected meteor echoes, effectively providing vertical profiles of horizontal wind estimates. Spectral and harmonic analyses were made on the horizontal wind averages, and the main tidal components were identified. Diurnal and semidiurnal oscillations were found persistently, and six, 8, and 48 hour oscillations were more intermittent, but

  5. PREFACE: Annual Conference on Functional Materials and Nanotechnologies - FM&NT 2011

    NASA Astrophysics Data System (ADS)

    Sternberg, Andris; Muzikante, Inta; Zicans, Janis

    2011-06-01

    Conference photograph ERAF logo International Organizing Committee Andris Sternberg (chairperson), Institute of Solid State Physics, University of Latvia, Latvia, MATERA Juras Banys, Vilnius University, Lithuania Gunnar Borstel, University of Osnabrück, Germany Niels E Christensen, University of Aarhus, Denmark Robert A Evarestov, St. Petersburg State University, Russia Claes-Goran Granqvist, Uppsala University, Sweden Dag Høvik, The Research Council of Norway, Norway, MATERA Marco Kirm, Institute of Physics, University of Tartu, Estonia Vladislav Lemanov, Ioffe Physical Technical Institute, Russia Witold Lojkowski, Institute of High Pressure Physics, Poland Ergo Nommiste, University of Tartu, Estonia Helmut Schober, Institut Laue-Langevin, France Sisko Sipilä, Finnish Funding Agency for Technology and Innovation, Finland, MATERA Ingólfur Torbjörnsson, Icelandic Centre for Research, Iceland, MATERA Marcel H Van de Voorde, University of Technology Delft, The Netherlands International Program Committee Inta Muzikante (chairperson), Institute of Solid State Physics, University of Latvia, Latvia, MATERA Liga Berzina-Cimdina, Institute of Biomaterials and Biomechanics, Riga Technical University, Latvia Janis Grabis, Institute of Inorganic Chemistry, Riga Technical University, Latvia Leonid V Maksimov, Vavilov State Optical Institute, Russia Linards Skuja, Institute of Solid State Physics, University of Latvia, Latvia Maris Springis, Institute of Solid State Physics, University of Latvia, Latvia Ilmars Zalite, Institute of Inorganic Chemistry, Riga Technical University, Latvia Janis Zicans, Institute of Polymers, Riga Technical University Local Committee: Liga Grinberga, Anatolijs Sarakovskis, Jurgis Grube, Raitis Siatkovskis, Maris Kundzins, Anna Muratova, Maris Springis, Aivars Vembris, Krisjanis Smits, Andris Fedotovs, Dmitrijs Bocarovs, Anastasija Jozepa, Andris Krumins.

  6. EDITORIAL: Focus on Advances in Surface and Interface Science 2009 FOCUS ON ADVANCES IN SURFACE AND INTERFACE SCIENCE 2009

    NASA Astrophysics Data System (ADS)

    Aeschlimann, Martin; Schneider, Wolf-Dieter

    2009-12-01

    to date look into the future. Focus on Contents Self-organized atomic nanowires of noble metals on Ge(001): atomic structure and electronic properties J Schäfer, S Meyer, C Blumenstein, K Roensch, R Claessen, S Mietke, M Klinke, T Podlich, R Matzdorf, A A Stekolnikov, S Sauer and F Bechstedt The role of polymorphism in organic thin films: oligoacenes investigated from first principles Claudia Ambrosch-Draxl, Dmitrii Nabok, Peter Puschnig and Christian Meisenbichler Searching for Si-based spintronics by first principles calculations Mahboubeh Hortamani, Leonid Sandratskii, Peter Kratzer and Ingrid Mertig Measuring spin polarization vectors in angle-resolved photoemission spectroscopy F Meier, J H Dil1 and J Osterwalder Hard x-ray photoelectron spectroscopy of oxide hybrid and heterostructures: a new method for the study of buried interfaces R Claessen, M Sing, M Paul, G Berner, A Wetscherek, A Müller and W Drube Single-atom contacts with a scanning tunnelling microscope J Kröger, N Néel, A Sperl, Y F Wang and R Berndt Electron-phonon coupling at surfaces and interfaces Ph Hofmann, I Yu Sklyadneva, E D L Rienks and E V Chulkov Adsorption of cobalt (II) octaethylporphyrin and 2H-octaethylporphyrin on Ag(111): new insight into the surface coordinative bond Yun Bai, Florian Buchner, Ina Kellner, Martin Schmid, Florian Vollnhals, Hans-Peter Steinrück, Hubertus Marbach and J Michael Gottfried Properties of metal-water interfaces studied from first principles Sebastian Schnur and Axel Groß Introducing artificial length scales to tailor magnetic properties J Fassbender, T Strache, M O Liedke, D Markó, S Wintz, K Lenz, A Keller, S Facsko, I Mönch and J McCord

  7. Limits on efficient computation in the physical world

    NASA Astrophysics Data System (ADS)

    Aaronson, Scott Joel

    More than a speculative technology, quantum computing seems to challenge our most basic intuitions about how the physical world should behave. In this thesis I show that, while some intuitions from classical computer science must be jettisoned in the light of modern physics, many others emerge nearly unscathed; and I use powerful tools from computational complexity theory to help determine which are which. In the first part of the thesis, I attack the common belief that quantum computing resembles classical exponential parallelism, by showing that quantum computers would face serious limitations on a wider range of problems than was previously known. In particular, any quantum algorithm that solves the collision problem---that of deciding whether a sequence of n integers is one-to-one or two-to-one---must query the sequence O (n1/5) times. This resolves a question that was open for years; previously no lower bound better than constant was known. A corollary is that there is no "black-box" quantum algorithm to break cryptographic hash functions or solve the Graph Isomorphism problem in polynomial time. I also show that relative to an oracle, quantum computers could not solve NP-complete problems in polynomial time, even with the help of nonuniform "quantum advice states"; and that any quantum algorithm needs O (2n/4/n) queries to find a local minimum of a black-box function on the n-dimensional hypercube. Surprisingly, the latter result also leads to new classical lower bounds for the local search problem. Finally, I give new lower bounds on quantum one-way communication complexity, and on the quantum query complexity of total Boolean functions and recursive Fourier sampling. The second part of the thesis studies the relationship of the quantum computing model to physical reality. I first examine the arguments of Leonid Levin, Stephen Wolfram, and others who believe quantum computing to be fundamentally impossible. I find their arguments unconvincing without a "Sure

  8. The Biological Big Bang model for the major transitions in evolution

    PubMed Central

    Koonin, Eugene V

    2007-01-01

    was reviewed by William Martin, Sergei Maslov, and Leonid Mirny. PMID:17708768

  9. Meteor Search by Spirit, Sol 668

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Annotated Meteor Search by Spirit, Sol 668

    The panoramic cameras on NASA's Mars Exploration Rovers are about as sensitive as the human eye at night. The cameras can see the same bright stars that we can see from Earth, and the same patterns of constellations dot the night sky. Scientists on the rover team have been taking images of some of these bright stars as part of several different projects. One project is designed to try to capture 'shooting stars,' or meteors, in the martian night sky. 'Meteoroids' are small pieces of comets and asteroids that travel through space and eventually run into a planet. On Earth, we can sometimes see meteoroids become brilliant, long 'meteors' streaking across the night sky as they burn up from the friction in our atmosphere. Some of these meteors survive their fiery flight and land on the surface (or in the ocean) where, if found, they are called 'meteorites.' The same thing happens in the martian atmosphere, and Spirit even accidentally discovered a meteor while attempting to obtain images of Earth in the pre-dawn sky back in March, 2004 (see http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040311a.html, and Selsis et al. (2005) Nature, vol 435, p. 581). On Earth, some meteors come in 'storms' or 'showers' at predictable times of the year, like the famous Perseid meteor shower in August or the Leonid meteor shower in November. These 'storms' happen when Earth passes through the same parts of space where comets sometimes pass. The meteors we see at these times are from leftover debris that was shed off of these comets.

    The same kind of thing is predicted for Mars, as well. Inspired by calculations about Martian meteor storms by meteor scientists from the University of Western Ontario in Canada and the Centre de Recherche en Astrophysique de Lyon in France, and also aided by other meteor research colleagues from NASA's Marshall Space Flight Center, scientists on

  10. Heterogeneous strain and composite P-T paths: the key for unravelling complex tectonic histories in polymetamorphic high-grade terrains

    NASA Astrophysics Data System (ADS)

    van Reenen, Dirk D.; Smit, C. Andre

    2010-05-01

    Leonid Perchuk calculated the first P-T paths for eclogites almost 40 years ago [1] and since then he has shown that P-T paths if correctly constructed, represent an accurate record of the thermal and dynamic evolution of high-grade metamorphic complexes [2]. This implies that P-T paths might serve as the basis for geodynamic models for the formation and exhumation of such complexes from the lower crustal levels [2]. His continued research in the Limpopo Complex of southern Africa also played an important role in the next direction in the study of complex high-grade polymetamorphic complexes. This new direction involves the link between composite (kinked) P-T paths [5; 6; 8] and the critical role of heterogeneous strain in the development and preservation of distinct granulite facies events at the regional, outcrop, hand specimen, and thin section scales [7; 9; 10]. Heterogeneous deformation that operated on the thin section scale allowed the construction of kinked P-T paths from single thin sections [5; 6; 9] and the integration of the P-T data with structural and isotopic geochronology [7; 9; 10]. D-P-T-t paths thus constructed not only allow the nature of polymetamorphism in the Limpopo Complex of southern Africa to be established, but also assisted in the construction of tectonic models for the evolution of this complex high-grade polymetamorphic complex. This complex evolution is demonstrated by the configuration of a kinked P-T path (5; 9) that reflects the following distinct stages of the multi-cycle D-P-T-t evolution of the Central Zone: (i) the earliest DC1 path reflects the emplacement before ~2.63Ga of the Limpopo Complex at the crustal level of ~20km. The DC1 stage of the D1/M1 exhumation event was accompanied by the formation of early D2A isoclinal folds; (ii) The DC2 stage of the D1/M1 exhumation event reflects the emplacement before ~2.61Ga of the rocks at the crustal level of ~15km. The DC2 stage was accompanied by the formation of major D2B sheath

  11. EDITORIAL: Message from the Editor Message from the Editor

    NASA Astrophysics Data System (ADS)

    Thomas, Paul

    2012-01-01

    Board Members, Guest Editors of special editions and those referees who were already listed in the last years. The following people have been selected: Marina Becoulet, CEA Cadarache, France Russell Doerner, University of California - San Diego, USA Emiliano Fable, Max-Planck-Institut fuer Plasmaphysik, Germany Akihide Fujisawa, Kyushi University, Japan Gerardo Giruzzi, CEA Cadarache, France Grigory Kagan, LANL, USA Morten Lennholm, CCFE, UK Akinobu Matsuyama, NIFS, Japan Peter Stangeby, University of Toronto, Canada Leonid Zakharov, PPPL, USA In addition, there is a group of several hundred referees who have helped us in the past year to maintain the high scientific standard of Nuclear Fusion. At the end of this issue we give the full list of all referees for 2011. Our thanks to them! Authors The winner of the 2011 Nuclear Fusion Award is H. Urano, for the paper 'Dimensionless parameter dependence of H-mode pedestal width using hydrogen and deuterium plasmas in JT-60U' (Nucl. Fusion 48 045008). The award was presented at the Plasma Conference 2011 (Joint meeting of 28th JSPF Annual Meeting, The 29th Symposium on Plasma Processing, and Division of Plasma Physics, 2011 Autumn Meeting of The Physical Society of Japan). This is the sixth year that the International Atomic Energy Agency (IAEA) has awarded an annual prize to honour exceptional work published in Nuclear Fusion. IOP Publishing has generously made a contribution of $2500 to the award. The Nuclear Fusion Electronic Archive The journal's electronic archive has been online since the beginning of the year. The archive has been a roaring success and has contributed to the nearly 300 000 downloads of journal papers in 2011. The archive can be accessed via http://iopscience.iop.org/0029-5515/page/Archive. It has direct links to 16 landmark papers, from authors such as Artsimovich and Mercier. The Nuclear Fusion office and IOP Publishing Just as the journal depends on the authors and referees, so its success is also

  12. Editorial: Focus on Atom Optics and its Applications

    NASA Astrophysics Data System (ADS)

    Schmidt-Kaler, F.; Pfau, T.; Schmelcher, P.; Schleich, W.

    2010-06-01

    Couvert, B Georgeot and D Guéry-Odelin Analysis of the entanglement between two individual atoms using global Raman rotations A Gaëtan, C Evellin, J Wolters, P Grangier, T Wilk and A Browaeys Spin polarization transfer in ground and metastable helium atom collisions D Vrinceanu and H R Sadeghpour A fiber Fabry-Perot cavity with high finesse D Hunger, T Steinmetz, Y Colombe, C Deutsch, T W Hänsch and J Reichel Atomic wave packets in amplitude-modulated vertical optical lattices A Alberti, G Ferrari, V V Ivanov, M L Chiofalo and G M Tino Atom interferometry with trapped Bose-Einstein condensates: impact of atom-atom interactions Julian Grond, Ulrich Hohenester, Igor Mazets and Jörg Schmiedmayer Storage of protonated water clusters in a biplanar multipole rf trap C Greve, M Kröner, S Trippel, P Woias, R Wester and M Weidemüller Single-atom detection on a chip: from realization to application A Stibor, H Bender, S Kühnhold, J Fortágh, C Zimmermann and A Günther Ultracold atoms as a target: absolute scattering cross-section measurements P Würtz, T Gericke, A Vogler and H Ott Entanglement-assisted atomic clock beyond the projection noise limit Anne Louchet-Chauvet, Jürgen Appel, Jelmer J Renema, Daniel Oblak, Niels Kjaergaard and Eugene S Polzik Towards the realization of atom trap trace analysis for 39Ar J Welte, F Ritterbusch, I Steinke, M Henrich, W Aeschbach-Hertig and M K Oberthaler Resonant superfluidity in an optical lattice I Titvinidze, M Snoek and W Hofstetter Interference of interacting matter waves Mattias Gustavsson, Elmar Haller, Manfred J Mark, Johann G Danzl, Russell Hart, Andrew J Daley and Hanns-Christoph Nägerl Magnetic trapping of NH molecules with 20 s lifetimes E Tsikata, W C Campbell, M T Hummon, H-I Lu and J M Doyle Imprinting patterns of neutral atoms in an optical lattice using magnetic resonance techniques Michal Karski, Leonid Förster, Jai-Min Choi, Andreas Steffen, Noomen Belmechri, Wolfgang Alt, Dieter Meschede and Artur Widera

  13. Editorial: Focus on Atom Optics and its Applications

    NASA Astrophysics Data System (ADS)

    Schmidt-Kaler, F.; Pfau, T.; Schmelcher, P.; Schleich, W.

    2010-06-01

    Couvert, B Georgeot and D Guéry-Odelin Analysis of the entanglement between two individual atoms using global Raman rotations A Gaëtan, C Evellin, J Wolters, P Grangier, T Wilk and A Browaeys Spin polarization transfer in ground and metastable helium atom collisions D Vrinceanu and H R Sadeghpour A fiber Fabry-Perot cavity with high finesse D Hunger, T Steinmetz, Y Colombe, C Deutsch, T W Hänsch and J Reichel Atomic wave packets in amplitude-modulated vertical optical lattices A Alberti, G Ferrari, V V Ivanov, M L Chiofalo and G M Tino Atom interferometry with trapped Bose-Einstein condensates: impact of atom-atom interactions Julian Grond, Ulrich Hohenester, Igor Mazets and Jörg Schmiedmayer Storage of protonated water clusters in a biplanar multipole rf trap C Greve, M Kröner, S Trippel, P Woias, R Wester and M Weidemüller Single-atom detection on a chip: from realization to application A Stibor, H Bender, S Kühnhold, J Fortágh, C Zimmermann and A Günther Ultracold atoms as a target: absolute scattering cross-section measurements P Würtz, T Gericke, A Vogler and H Ott Entanglement-assisted atomic clock beyond the projection noise limit Anne Louchet-Chauvet, Jürgen Appel, Jelmer J Renema, Daniel Oblak, Niels Kjaergaard and Eugene S Polzik Towards the realization of atom trap trace analysis for 39Ar J Welte, F Ritterbusch, I Steinke, M Henrich, W Aeschbach-Hertig and M K Oberthaler Resonant superfluidity in an optical lattice I Titvinidze, M Snoek and W Hofstetter Interference of interacting matter waves Mattias Gustavsson, Elmar Haller, Manfred J Mark, Johann G Danzl, Russell Hart, Andrew J Daley and Hanns-Christoph Nägerl Magnetic trapping of NH molecules with 20 s lifetimes E Tsikata, W C Campbell, M T Hummon, H-I Lu and J M Doyle Imprinting patterns of neutral atoms in an optical lattice using magnetic resonance techniques Michal Karski, Leonid Förster, Jai-Min Choi, Andreas Steffen, Noomen Belmechri, Wolfgang Alt, Dieter Meschede and Artur Widera

  14. Meteor Search by Spirit, Sol 668

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Annotated Meteor Search by Spirit, Sol 668

    The panoramic cameras on NASA's Mars Exploration Rovers are about as sensitive as the human eye at night. The cameras can see the same bright stars that we can see from Earth, and the same patterns of constellations dot the night sky. Scientists on the rover team have been taking images of some of these bright stars as part of several different projects. One project is designed to try to capture 'shooting stars,' or meteors, in the martian night sky. 'Meteoroids' are small pieces of comets and asteroids that travel through space and eventually run into a planet. On Earth, we can sometimes see meteoroids become brilliant, long 'meteors' streaking across the night sky as they burn up from the friction in our atmosphere. Some of these meteors survive their fiery flight and land on the surface (or in the ocean) where, if found, they are called 'meteorites.' The same thing happens in the martian atmosphere, and Spirit even accidentally discovered a meteor while attempting to obtain images of Earth in the pre-dawn sky back in March, 2004 (see http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040311a.html, and Selsis et al. (2005) Nature, vol 435, p. 581). On Earth, some meteors come in 'storms' or 'showers' at predictable times of the year, like the famous Perseid meteor shower in August or the Leonid meteor shower in November. These 'storms' happen when Earth passes through the same parts of space where comets sometimes pass. The meteors we see at these times are from leftover debris that was shed off of these comets.

    The same kind of thing is predicted for Mars, as well. Inspired by calculations about Martian meteor storms by meteor scientists from the University of Western Ontario in Canada and the Centre de Recherche en Astrophysique de Lyon in France, and also aided by other meteor research colleagues from NASA's Marshall Space Flight Center, scientists on

  15. NRAO Scientists on Team Receiving International Astronautics Award

    NASA Astrophysics Data System (ADS)

    2005-10-01

    , a radio telescope bigger than the Earth." In addition to Fomalont and Romney, they are: Hisashi Hirabayashi, of the Institute of Space and Astronautical Science and Japan Aerospace Exploration Agency (ISAS/JAXA), Haruto Hirosawa (ISAS/JAXA), Peter Dewdney of Canada's Dominion Radio Astrophysical Observatory, Leonid Gurvits of the Joint Institute for VLBI in Europe (JIVE, The Netherlands), Makoto Inoue of the National Astronomical Observatory of Japan (NAOJ), David Jauncey of the Australia Telescope National Facility, Noriyuki Kawaguchi (NAOJ), Hideyuki Kobayashi (NAOJ), Kazuo Miyoshi (Mitsubishi Electric Corporation, Japan), Yasuhiro Murata (ISAS/JAXA), Takeshi Orii (NEC, Japan) Robert Preston of NASA's Jet Propulsion Laboratory (JPL), and Joel Smith (JPL). The International Academy of Astronautics was founded in August 1960 in Stockholm, Sweden, during the 11th International Astronautical Congress. The Academy aims to foster the development of astronautics for peaceful purposes; recognize individuals who have distinguished themselves in a related branch of science or technology; provide a program through which members may contribute to international endeavours; cooperation in the advancement of aerospace science. Previous recipients of the Laurels for Team Achievement Award are the Russian Mir Space Station Team (2001), the U.S. Space Shuttle Team (2002), the Solar and Heliospheric Observatory (SOHO) Team (2003), and the Hubble Space Telescope Team (2004). The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  16. Meteorites, Bolides and Comets: A Tale of Inconsistency

    NASA Astrophysics Data System (ADS)

    Jakes, P.; Padevet, V.

    1992-07-01

    Inhomogeneity of cometary nuclei has been established through the observed disruptions of comets [1] and through the determination of dust particle composition during the encounter of the Vega and Giotto satellites with comet Halley [2,3,4]. The raisin bread model of cometary nuclei [5,6] assumes the presence of solid (rock) and dust particle material set in the volatile rich, ice- cemented material. Rock material may contribute to the formation of dust particles. Gombosi and Houpis [5] argued that only the composition of dust particles derived from the icy, volatile component of the comet were analyzed and implied thus that the third cometary component present (raisins/rocks) has not been examined. The compositions of the cometary (Halley) dust and the interplanetary dust particles (IDPs) are "chondritic" (Blanford et al., 1988). It is difficult, therefore to estimate the proportion of cometary to asteroid-derived dust in near Earth space, e.g., among the IDPs [7] unless other criteria are available. Bolide multistation photographic tracking allows the determination of the orbital preencounter parameters of solid bodies (0.01-100,000 kg in mass) with the Earth, and allows us to classify them according to their ablation coefficient (tau), penetration depth into the atmosphere (PE), theoretical densities (sigma), and terminal velocities (V(sub)E). Four groups are recognized (Table 1). Three of the type I bolides were recovered as ordinary chondrites (Pribram, Lost City, and Innisfree). Ceplecha [8] has shown that 38% of bolides (fireballs) come from cometary orbits (11% from highly eccentric orbits typical of new comets), but most of the bolides (62%) originate at asteroidal orbits. Seven of the 14 known meteoric showers could be attributed to known comets: N,S Taurids to 1970 P/Encke, Lyrids to 1861 I Thatcher-Beaker, Perseids to 1862 III Swift-Tuttle- Simons, Orionids to 1835 III P/Halley, Draconids to 1946 V P/Giacobini-Zinner, Leonids to 1966 I Tempel

  17. PREFACE: Semiconducting oxides Semiconducting oxides

    NASA Astrophysics Data System (ADS)

    Catlow, Richard; Walsh, Aron

    2011-08-01

    their help in producing this special section. We hope that it conveys some of the excitement and significance of the field. Semiconducting oxides contents Chemical bonding in copper-based transparent conducting oxides: CuMO2 (M = In, Ga, Sc) K G Godinho, B J Morgan, J P Allen, D O Scanlon and G W Watson Electrical properties of (Ba, Sr)TiO3 thin films with Pt and ITO electrodes: dielectric and rectifying behaviourShunyi Li, Cosmina Ghinea, Thorsten J M Bayer, Markus Motzko, Robert Schafranek and Andreas Klein Orientation dependent ionization potential of In2O3: a natural source for inhomogeneous barrier formation at electrode interfaces in organic electronicsMareike V Hohmann, Péter Ágoston, André Wachau, Thorsten J M Bayer, Joachim Brötz, Karsten Albe and Andreas Klein Cathodoluminescence studies of electron irradiation effects in n-type ZnOCasey Schwarz, Yuqing Lin, Max Shathkin, Elena Flitsiyan and Leonid Chernyak Resonant Raman scattering in ZnO:Mn and ZnO:Mn:Al thin films grown by RF sputteringM F Cerqueira, M I Vasilevskiy, F Oliveira, A G Rolo, T Viseu, J Ayres de Campos, E Alves and R Correia Structure and electrical properties of nanoparticulate tungsten oxide prepared by microwave plasma synthesisM Sagmeister, M Postl, U Brossmann, E J W List, A Klug, I Letofsky-Papst, D V Szabó and R Würschum Charge compensation in trivalent cation doped bulk rutile TiO2Anna Iwaszuk and Michael Nolan Deep level transient spectroscopy studies of n-type ZnO single crystals grown by different techniquesL Scheffler, Vl Kolkovsky, E V Lavrov and J Weber Microstructural and conductivity changes induced by annealing of ZnO:B thin films deposited by chemical vapour depositionC David, T Girardeau, F Paumier, D Eyidi, B Lacroix, N Papathanasiou, B P Tinkham, P Guérin and M Marteau Multi-component transparent conducting oxides: progress in materials modellingAron Walsh, Juarez L F Da Silva and Su-Huai Wei Thickness dependence of the strain, band gap and transport properties of

  18. PREFACE: Semiconducting oxides Semiconducting oxides

    NASA Astrophysics Data System (ADS)

    Catlow, Richard; Walsh, Aron

    2011-08-01

    their help in producing this special section. We hope that it conveys some of the excitement and significance of the field. Semiconducting oxides contents Chemical bonding in copper-based transparent conducting oxides: CuMO2 (M = In, Ga, Sc) K G Godinho, B J Morgan, J P Allen, D O Scanlon and G W Watson Electrical properties of (Ba, Sr)TiO3 thin films with Pt and ITO electrodes: dielectric and rectifying behaviourShunyi Li, Cosmina Ghinea, Thorsten J M Bayer, Markus Motzko, Robert Schafranek and Andreas Klein Orientation dependent ionization potential of In2O3: a natural source for inhomogeneous barrier formation at electrode interfaces in organic electronicsMareike V Hohmann, Péter Ágoston, André Wachau, Thorsten J M Bayer, Joachim Brötz, Karsten Albe and Andreas Klein Cathodoluminescence studies of electron irradiation effects in n-type ZnOCasey Schwarz, Yuqing Lin, Max Shathkin, Elena Flitsiyan and Leonid Chernyak Resonant Raman scattering in ZnO:Mn and ZnO:Mn:Al thin films grown by RF sputteringM F Cerqueira, M I Vasilevskiy, F Oliveira, A G Rolo, T Viseu, J Ayres de Campos, E Alves and R Correia Structure and electrical properties of nanoparticulate tungsten oxide prepared by microwave plasma synthesisM Sagmeister, M Postl, U Brossmann, E J W List, A Klug, I Letofsky-Papst, D V Szabó and R Würschum Charge compensation in trivalent cation doped bulk rutile TiO2Anna Iwaszuk and Michael Nolan Deep level transient spectroscopy studies of n-type ZnO single crystals grown by different techniquesL Scheffler, Vl Kolkovsky, E V Lavrov and J Weber Microstructural and conductivity changes induced by annealing of ZnO:B thin films deposited by chemical vapour depositionC David, T Girardeau, F Paumier, D Eyidi, B Lacroix, N Papathanasiou, B P Tinkham, P Guérin and M Marteau Multi-component transparent conducting oxides: progress in materials modellingAron Walsh, Juarez L F Da Silva and Su-Huai Wei Thickness dependence of the strain, band gap and transport properties of

  19. EDITORIAL: Focus on Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    2003-09-01

    The study of carbon nanotubes, since their discovery by Iijima in 1991, has become a full research field with significant contributions from all areas of research in solid-state and molecular physics and also from chemistry. This Focus Issue in New Journal of Physics reflects this active research, and presents articles detailing significant advances in the production of carbon nanotubes, the study of their mechanical and vibrational properties, electronic properties and optical transitions, and electrical and transport properties. Fundamental research, both theoretical and experimental, represents part of this progress. The potential applications of nanotubes will rely on the progress made in understanding their fundamental physics and chemistry, as presented here. We believe this Focus Issue will be an excellent guide for both beginners and experts in the research field of carbon nanotubes. It has been a great pleasure to edit the many excellent contributions from Europe, Japan, and the US, as well from a number of other countries, and to witness the remarkable effort put into the manuscripts by the contributors. We thank all the authors and referees involved in the process. In particular, we would like to express our gratitude to Alexander Bradshaw, who invited us put together this Focus Issue, and to Tim Smith and the New Journal of Physics staff for their extremely efficient handling of the manuscripts. Focus on Carbon Nanotubes Contents Transport theory of carbon nanotube Y junctions R Egger, B Trauzettel, S Chen and F Siano The tubular conical helix of graphitic boron nitride F F Xu, Y Bando and D Golberg Formation pathways for single-wall carbon nanotube multiterminal junctions Inna Ponomareva, Leonid A Chernozatonskii, Antonis N Andriotis and Madhu Menon Synthesis and manipulation of carbon nanotubes J W Seo, E Couteau, P Umek, K Hernadi, P Marcoux, B Lukic, Cs Mikó, M Milas, R Gaál and L Forró Transitional behaviour in the transformation from active end

  20. EDITORIAL: Focus on Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    2003-09-01

    The study of carbon nanotubes, since their discovery by Iijima in 1991, has become a full research field with significant contributions from all areas of research in solid-state and molecular physics and also from chemistry. This Focus Issue in New Journal of Physics reflects this active research, and presents articles detailing significant advances in the production of carbon nanotubes, the study of their mechanical and vibrational properties, electronic properties and optical transitions, and electrical and transport properties. Fundamental research, both theoretical and experimental, represents part of this progress. The potential applications of nanotubes will rely on the progress made in understanding their fundamental physics and chemistry, as presented here. We believe this Focus Issue will be an excellent guide for both beginners and experts in the research field of carbon nanotubes. It has been a great pleasure to edit the many excellent contributions from Europe, Japan, and the US, as well from a number of other countries, and to witness the remarkable effort put into the manuscripts by the contributors. We thank all the authors and referees involved in the process. In particular, we would like to express our gratitude to Alexander Bradshaw, who invited us put together this Focus Issue, and to Tim Smith and the New Journal of Physics staff for their extremely efficient handling of the manuscripts. Focus on Carbon Nanotubes Contents <;A article="1367-2630/5/1/117">Transport theory of carbon nanotube Y junctions R Egger, B Trauzettel, S Chen and F Siano The tubular conical helix of graphitic boron nitride F F Xu, Y Bando and D Golberg Formation pathways for single-wall carbon nanotube multiterminal junctions Inna Ponomareva, Leonid A Chernozatonskii, Antonis N Andriotis and Madhu Menon Synthesis and manipulation of carbon nanotubes J W Seo, E Couteau

  1. PREFACE: 2nd International Conference on Particle Physics in memoriam Engin Arık and her Colleagues

    NASA Astrophysics Data System (ADS)

    Çetin, Serkant Ali; Jenni, Peter; Erkcan Özcan, Veysi; Nefer Şenoğuz, Vedat

    2012-02-01

    experiments. There were 20 plenary and 35 contributed talks at the conference, and a majority of these presentations are included in this proceedings. We are grateful to all speakers, the collaborations represented, and all members of the advisory and organizing committees for their invaluable contributions which enabled the conference to reach such a high scientific quality with many exciting results and discussions, making it a big success. Serkant Ali Çetin Chair of the Organizing Committee Peter Jenni Chair of the Scientific Advisory Committee Scientific Advisory Committee Organizing Committee Ovsat AbdinovANAS, AzerbaijanKazem AziziDoğuş U. Metin ArıkBoğaziçi U., TurkeySerkant Ali Çetin*Doğuş U. Albert De RoeckCERN, SwitzerlandZuhal KaplanBoğaziçi U. Daniel DenegriCEA, FranceÖzgül KurtuluşDoğuş U. Samim ErhanUCLA, USAErkcan ÖzcanBoğaziçi U. Dan GreenFNAL, USANefer ŞenoğuzDoğuş U. Erhan GülmezBoğaziçi U., Turkeyİsmail UmanDoğuş U. Rolf HeuerCERN, Switzerland Peter Jenni*CERN, Switzerland*Committee Chairs Max KleinLiverpool U., UK Livio MapelliCERN, Switzerland Tatsuya NakadaEPFL, Switzerland Yaşar ÖnelIowa U., USA Gülsen ÖnengütÇukurova U., Turkey Ken PeachOxford U., UK Christoph RembserCERN, Switzerland Leonid RivkinPSI, Switzerland Yannis SemertzidisBNL, USA Saleh SultansoyTOBB ETU, Turkey Gökhan ÜnelUCI, USA Konstantin ZioutasPatras U., Greece Organizing InstitutionsSupporting Institutions DogusCERN Doğuş UniversityCERN - European Organization for Nuclear Research BogaziciTUBA Boğaziçi UniversityTÜBA - The Turkish Academy of Sciences

  2. EDITORIAL: From reciprocal space to real space in surface science From reciprocal space to real space in surface science

    NASA Astrophysics Data System (ADS)

    Bartels, Ludwig; Ernst, Karl-Heinz

    2012-09-01

    Triest.let's finish—aus basta Some move atoms around to hear how they sound.Karl-Heinz Rieder, Erice, 6 April 1998 From reciprocal space to real space in surface science contents From reciprocal space to real space in surface scienceLudwig Bartels and Karl-Heinz Ernst Karl-Heinz Reider: the quiet pioneerGiorgio Benedek Scattering of CO and N2 molecules by a graphite surfaceJunepyo Oh, Takahiro Kondo, Keitaro Arakawa, Yoshihiko Saito, Junji Nakamura, W W Hayes and J R Manson Helium, neon and argon diffraction from Ru(0001)M Minniti, C Díaz, J L Fernández Cuñado, A Politano, D Maccariello, F Martín, D Farías and R Miranda Enhanced charge transfer in a monolayer of the organic charge transfer complex TTF-TNAP on Au(111)T R Umbach, I Fernandez-Torrente, J N Ladenthin, J I Pascual and K J Franke Extended pattern recognition scheme for self-learning kinetic Monte Carlo simulationsSyed Islamuddin Shah, Giridhar Nandipati, Abdelkader Kara and Talat S Rahman Acetylene on Cu(111): imaging a molecular surface arrangement with a constantly rearranging tipYeming Zhu, Jonathan Wyrick, Kamelia D Cohen, Katie Marie Magnone, Connor Holzke, Daniel Salib, Quan Ma, Dezheng Sun and Ludwig Bartels Coulomb attraction during the carpet growth mode of NaClFriederike Matthaei, Sarah Heidorn, Konrad Boom, Cord Bertram, Ali Safiei, Jörg Henzl and Karina Morgenstern Molecular self-assembly on an insulating surface: interplay between substrate templating and intermolecular interactionsMarkus Kittelmann, Philipp Rahe and Angelika Kühnle Vertical manipulation of native adatoms on the InAs(111)A surfaceJ Yang, C Nacci, J Martínez-Blanco, K Kanisawa and S Fölsch Charge transfer between isomer domains on n+-doped Si(111)-2 × 1: energetic stabilizationR M Feenstra, G Bussetti, B Bonanni, A Violante, C Goletti, P Chiaradia, M G Betti and C Mariani Probing the properties of metal-oxide interfaces: silica films on Mo and Ru supportsLeonid Lichtenstein, Markus Heyde, Stefan Ulrich, Niklas Nilius

  3. Obituary: Thomas C. Van Flandern (1940-2009)

    NASA Astrophysics Data System (ADS)

    Dunham, David; Slabinski, Victor

    2011-12-01

    planetary formation. The Bulletin claimed mainstream scientists preferred making ad hoc corrections to the theories rather than acknowledge fundamental difficulties that might jeopardize their funding. Tom Van Flandern's advocacy of an artificial origin for the "face on Mars," especially after higher-resolution images were taken in 2001, antagonized many. His questioning of the speed of gravity, first published in a 1998 paper in Physics Letters A, provoked additional attacks from relativists. He showed the same persistence with these controversies that had enabled him to solve complex programming and celestial mechanics problems. Tom Van Flandern did not reject General Relativity as some have asserted, but rather rejected its geometrical interpretation. He said: "General relativity has a geometric and a field interpretation. If angular momentum conservation is invoked in the geometric interpretation to explain experiments, the causality principle is violated. The field interpretation avoids this problem by allowing faster-than-light propagation in forward time." For more, see http://www.metaresearch.org/cosmology/gravity/speed_limit.asp. Tom Van Flandern strongly attacked some alternative theories, such as Velikovsky's ideas of recent planetary close approaches, turning one of Velikovsky's supporters, C. L. Ellenberger, into a strong critic. If not for these antagonisms, the "mainstream" part of Tom Van Flandern's work in later years might be better acknowledged, including his "Eclipse Edge" company that organized expeditions to several solar eclipses, and his work with E. Lyytinen on the passage of Earth through cometary debris trails. Their prediction was closest to the observed time of the Leonid storm maximum of November 2001. Tom Van Flandern held memberships in the International Astronomical Union, the American Astronomical Society (and in its Divisions on Dynamical Astronomy and Planetary Sciences), and several other scientific organizations. He received second

  4. Radio Telescopes Will Add to Cassini-Huygens Discoveries

    NASA Astrophysics Data System (ADS)

    2004-12-01

    accuracy. They expect to measure the probe's position within two-thirds of a mile (1 kilometer) at a distance of nearly 750 million miles. "That's like being able to sit in your back yard and watch the ball in a ping-pong game being played on the Moon," said Leonid Gurvits of JIVE. Both the JPL and JIVE teams will record the data collected by the radio telescopes and process it later. In the case of the Doppler measurements, some real-time information may be available, depending on the strength of the signal, but the scientists on this team also plan to do their detailed analysis on recorded data. The JPL team is utilizing special instrumentation from the Deep Space Network called Radio Science Receivers. One will be loaned to the GBT and another to the Parkes radio observatory. "This is the same instrument that allowed us to support the challenging communications during the landing of the Spirit and Opportunity Mars rovers as well as the Cassini Saturn Orbit Insertion when the received radio signal was very weak," said Sami Asmar, the JPL scientist responsible for the data recording. When the Galileo spacecraft's probe entered Jupiter's atmosphere in 1995, a JPL team used the NSF's Very Large Array (VLA) radio telescope in New Mexico to directly track the probe's signal. Adding the data from the VLA to that experiment dramatically improved the accuracy of the wind-speed measurements. "The Galileo probe gave us a surprise. Contrary to some predictions, we learned that Jupiter's winds got stronger as we went deeper into its atmosphere. That tells us that those deeper winds are not driven entirely by sunlight, but also by heat coming up from the planet's core. If we get lucky at Titan, we'll get surprises there, too," said Robert Preston, another JPL scientist. The Huygens probe is a spacecraft built by the European Space Agency (ESA). In addition to the NRAO telescopes, the JPL Doppler Wind Experiment will use the Australia Telescope National Facility and other radio

  5. Catching a Falling Star

    NASA Astrophysics Data System (ADS)

    2004-07-01

    . Comets are another important source of meteoroids and perhaps the most spectacular. After many visits near the Sun, a comet "dirty-snowball" nucleus of ice and dust decays and fragments, leaving a trail of meteoroids along its orbit. Some "meteoroid streams" cross the earth's orbit and when our planet passes through them, some of these particles will enter the atmosphere. The outcome is a meteor shower - the most famous being the "Perseids" in the month of August [2] and the "Leonids" in November. Thus, although meteors are referred to as "shooting" or "falling stars" in many languages, they are of a very different nature. More information The research presented in this paper is published in the journal Meteoritics and Planetary Science, Vol. 39, Nr. 4, p. 1, 2004 ("Spectroscopic anatomy of a meteor trail cross section with the ESO Very Large Telescope", by P. Jenniskens et al.). Notes [1] The team is composed of Peter Jenniskens (SETI Institute, USA), Emmanuël Jehin (ESO), Remi Cabanac (Pontificia Universidad Catolica de Chile), Christophe Laux (Ecole Centrale de Paris, France), and Iain Boyd (University of Michigan, USA). [2] The maximum of the Perseids is expected on August 12 after sunset and should be easily seen.