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Sample records for earth cosmic influences

  1. Cosmic Influence on the Sun-Earth Environment

    PubMed Central

    Mukherjee, Saumitra

    2008-01-01

    SOHO satellite data reveals geophysical changes before sudden changes in the Earth's Sun-Earth environment. The influence of extragalactic changes on the Sun as well as the Sun-Earth environment seems to be both periodic and episodic. The periodic changes in terms of solar maxima and minima occur every 11 years, whereas the episodic changes can happen at any time. Episodic changes can be monitored by cosmic ray detectors as a sudden increase or decrease of activity. During these solar and cosmic anomaly periods the environment of the Earth is affected. The Star-Sun-Earth connection has the potential to influence the thermosphere, atmosphere, ionosphere and lithosphere. Initial correlation of the cosmic and Sun-Earth connection has shown the possibility of predicting earthquakes, sudden changes in atmospheric temperatures and erratic rainfall/snowfall patterns. PMID:27873955

  2. Cosmic Rays at Earth

    NASA Astrophysics Data System (ADS)

    Grieder, P. K. F.

    In 1912 Victor Franz Hess made the revolutionary discovery that ionizing radiation is incident upon the Earth from outer space. He showed with ground-based and balloon-borne detectors that the intensity of the radiation did not change significantly between day and night. Consequently, the sun could not be regarded as the sources of this radiation and the question of its origin remained unanswered. Today, almost one hundred years later the question of the origin of the cosmic radiation still remains a mystery. Hess' discovery has given an enormous impetus to large areas of science, in particular to physics, and has played a major role in the formation of our current understanding of universal evolution. For example, the development of new fields of research such as elementary particle physics, modern astrophysics and cosmology are direct consequences of this discovery. Over the years the field of cosmic ray research has evolved in various directions: Firstly, the field of particle physics that was initiated by the discovery of many so-called elementary particles in the cosmic radiation. There is a strong trend from the accelerator physics community to reenter the field of cosmic ray physics, now under the name of astroparticle physics. Secondly, an important branch of cosmic ray physics that has rapidly evolved in conjunction with space exploration concerns the low energy portion of the cosmic ray spectrum. Thirdly, the branch of research that is concerned with the origin, acceleration and propagation of the cosmic radiation represents a great challenge for astrophysics, astronomy and cosmology. Presently very popular fields of research have rapidly evolved, such as high-energy gamma ray and neutrino astronomy. In addition, high-energy neutrino astronomy may soon initiate as a likely spin-off neutrino tomography of the Earth and thus open a unique new branch of geophysical research of the interior of the Earth. Finally, of considerable interest are the biological

  3. Cosmic rays and other rpace phenomena influenced on the Earth's climate

    NASA Astrophysics Data System (ADS)

    Lev, Dorman

    2016-07-01

    We consider effects of cosmic rays (CR) and some other space phenomena on the Earth's climate change. It is well known that the system of internal and external factors formatting the Earth's climate is very unstable: decreasing of planetary average annual temperature leads to an increase of planetary snow surface, and decreasing of the total annual solar energy input into the system decreases the planetary temperature even more. And inverse: increasing planetary temperature leads to an decrease of snow surface, and increasing of the total solar energy input into the system increases the planetary temperature even more. From this follows that even energetically small factors acted long time in one direction may have a big influence on climate change. In our opinion, the most important of these factors are CR (mostly through its influence on planetary cloudiness) and space dust (SD) through their influence on the flux of solar irradiation and on formation of clouds (these actions are in one direction). It is important that CR and SD influenced on global climate change in the same direction. Increasing of CR planetary intensity leads to increasing of formation clouds (especially low clouds on altitudes smaller than 3 km), increasing annual average of raining and decreasing of annual average planetary temperature. Increasing of SD decreases of solar irradiation and increases cloudiness what leads also to decreasing of annual average planetary temperature. Moreover, interactions of CR particles with dust granules decreases their dimensions what increased effectiveness of their actions on clouds. We consider data great variations of planetary temperature much before the beginning of the Earth's technological civilization (mostly caused by moving of the solar system around our Galaxy centre and collisions with molecular-dust clouds). We consider in details not only situation during the last hundred years, but also situation in the last one thousand years (and especially

  4. Influence of Sun and Other Cosmic Factors on Environment of the Earth

    DTIC Science & Technology

    2010-01-07

    of the secondary cosmic rays (mostly muons , electrons, neutrons and gammas) can provide highly cost-effective information on the key characteristics...Coronal mass ejection (CME) from the Sun the impact on the Galactic Cosmic rays (GCR) will be observed. Particle detector is vital for measuring the...modulation effects the sun poses on the ambient population of the Galactic Cosmic Rays (GCR). The known agents of these modulation effects are Solar Flares

  5. Does the presence of cosmic dust influence the displacement of the Earth's Magnetopause?

    NASA Astrophysics Data System (ADS)

    Mann, I.; Hamrin, M.

    2012-04-01

    In a recent paper Treumann and Baumjohann propose that dust particles in interplanetary space occasionally cause large compressions of the magnetopause that, in the absence of coronal mass ejections, are difficult to explain by other mechanisms (R.A. Treumann and W. Baumjohann, Ann. Geophys. 30, 119-130, 2012). They suggest that enhanced dust number density raises the contribution of the dust component to the solar wind dynamical pressure and hence to the pressure balance that determines the extension of the magnetopause. They quantify the influence of the dust component in terms of a variation of the magnetopause stagnation point distance. As a possible event to trigger the compressions they propose the encounters with meteoroid dust streams along Earth's orbit. We investigate the conditions under which these compressions may occur. The estimate by Treumann and Baumjohann of the magnetopause variation presupposes that the dust particles have reached solar wind speed. Acceleration by electromagnetic forces is efficient in the solar wind for dust particles that have a sufficiently large ratio of surface charge to mass (Mann et al. Plasma Phys. Contr. Fusion, Vol. 52, 124012, 2010). This applies to small dust particles that contribute little to the total dust mass in meteoroid streams. The major fraction of dust particles that reach high speed in the solar wind are nanometer-sized dust particles that form and are accelerated in the inner solar system (Czechowski and Mann, ApJ, Vol. 714, 89, 2010). Observations suggest that the flux of these nanodust particles near 1 AU is highly time-variable (Meyer-Vernet, et al. Solar Physics, Vol. 256, 463, 2009). We estimate a possible variation of the magnetopause stagnation point distance caused by these nanodust fluxes and by the dust associated to meteoroid streams. We conclude that the Earth's encounters with meteoroid dust streams are not likely to strongly influence the magnetopause according to the proposed effect. We

  6. Low cloud properties influenced by cosmic rays

    PubMed

    Marsh; Svensmark

    2000-12-04

    The influence of solar variability on climate is currently uncertain. Recent observations have indicated a possible mechanism via the influence of solar modulated cosmic rays on global cloud cover. Surprisingly the influence of solar variability is strongest in low clouds (cosmic rays. If confirmed it suggests that the average state of the heliosphere is important for climate on Earth.

  7. Cosmic Rays Variation Before Changes in Sun-Earth Environment

    NASA Astrophysics Data System (ADS)

    Mukherjee, S.

    2011-12-01

    Influence of cosmic rays variations on the Sun-Earth Environment has been observed before the changes in the atmospheric temperature, outbreak of influenza, cyclone, earthquake and tsunami. It has been recorded by Sun Observatory Heleospheric Observatory (SOHO) satellite data. Before the earthquake and tsunami the planetary indices (Kp) and Electron flux (E-flux) shows sudden changes followed by the atmospheric perturbations including very high temperature rise to sudden fall resulting snowfall in high altitude and rainfall in tropical areas. The active fault zones shows sudden faulting after the sudden drop in cosmic ray intensity and rise in Kp and E-flux. Besides the geo-environment the extraterrestrial influence on outbreak of H1N1 influenza has also been recorded based on the Mexico Cosmic ray data and its correlation with SOHO records. Distant stars have the potential to influence the heliophysical parameters by showering cosmic rays.

  8. THE COSMIC-RAY INTENSITY NEAR THE ARCHEAN EARTH

    SciTech Connect

    Cohen, O.; Drake, J. J.; Kota, J.

    2012-11-20

    We employ three-dimensional state-of-the-art magnetohydrodynamic models of the early solar wind and heliosphere and a two-dimensional model for cosmic-ray transport to investigate the cosmic-ray spectrum and flux near the Archean Earth. We assess how sensitive the cosmic-ray spectrum is to changes in the sunspot placement and magnetic field strength, the large-scale dipole magnetic field strength, the wind ram pressure, and the Sun's rotation period. Overall, our results confirm earlier work that suggested the Archean Earth would have experienced a greatly reduced cosmic-ray flux than is the case today. The cosmic-ray reduction for the early Sun is mainly due to themore » shorter solar rotation period and tighter winding of the Parker spiral, and to the different surface distribution of the more active solar magnetic field. These effects lead to a global reduction of the cosmic-ray flux at 1 AU by up to two orders of magnitude or more. Variations in the sunspot magnetic field have more effect on the flux than variations in the dipole field component. The wind ram pressure affects the cosmic-ray flux through its influence on the size of the heliosphere via the pressure balance with the ambient interstellar medium. Variations in the interstellar medium pressure experienced by the solar system in orbit through the Galaxy could lead to order of magnitude changes in the cosmic-ray flux at Earth on timescales of a few million years.« less

  9. Cosmic signatures in earth's seismic tremor?

    NASA Astrophysics Data System (ADS)

    Mulargia, Francesco

    2017-01-01

    Even in absence of earthquakes, each site on earth experiences continuous elastic vibrations which are mostly traced to the nonlinear interactions of ocean waves. However, the fine structure of the spectrum at mHz frequencies shows many persistent and highly significant narrow bandwidth peaks in surprising coincidence with solar acoustic eigenmodes. The feasibility of a common cosmic origin is evaluated through an estimate of the gravitational wave cross-section of the earth, combined with its elastic response and with the stochastic amplification produced by the interference of the cosmic signal with tremor of oceanic origin. The measured spectral peaks appear compatible with a gravitational monochromatic illumination at strains h ≳ 10-20, larger than those expected for any known gravitational stellar source. Hence, a gravitational source attribution to the tremor spectral peaks would call for a population of unknown non-luminous sources with well-defined mass-distance ratios.

  10. Cosmic dust in the earth's atmosphere.

    PubMed

    Plane, John M C

    2012-10-07

    This review discusses the magnitude of the cosmic dust input into the earth's atmosphere, and the resulting impacts from around 100 km to the earth's surface. Zodiacal cloud observations and measurements made with a spaceborne dust detector indicate a daily mass input of interplanetary dust particles ranging from 100 to 300 tonnes, which is in agreement with the accumulation rates of cosmic-enriched elements (Ir, Pt, Os and super-paramagnetic Fe) in polar ice cores and deep-sea sediments. In contrast, measurements in the middle atmosphere - by radar, lidar, high-flying aircraft and satellite remote sensing - indicate that the input is between 5 and 50 tonnes per day. There are two reasons why this huge discrepancy matters. First, if the upper range of estimates is correct, then vertical transport in the middle atmosphere must be considerably faster than generally believed; whereas if the lower range is correct, then our understanding of dust evolution in the solar system, and transport from the middle atmosphere to the surface, will need substantial revision. Second, cosmic dust particles enter the atmosphere at high speeds and undergo significant ablation. The resulting metals injected into the atmosphere are involved in a diverse range of phenomena, including: the formation of layers of metal atoms and ions; the nucleation of noctilucent clouds, which are a sensitive marker of climate change; impacts on stratospheric aerosols and O(3) chemistry, which need to be considered against the background of a cooling stratosphere and geo-engineering plans to increase sulphate aerosol; and fertilization of the ocean with bio-available Fe, which has potential climate feedbacks.

  11. The cosmic Era and the Earth

    NASA Astrophysics Data System (ADS)

    Closca-Grigore, Carmen

    THe book describes the main directions of development of cosmic research in the USA, USSR, Europe, Japan and China. The main inventors and creators of cosmic technics are designed : Tsiolkovskii, Tsander, Korolev, Oberth, Verner von Braun, Goddard and the most important cosmic flies by Sputnik, Gagarin, Tereshkova, Leonov, Armstrong. The main program of cosmic research are outlined in such areas as maps, geological research, meteorolgy, television, radio and military. The Romanian contributions are described: Ioan Vitez, Konrad Haas, Traian Vuia, Aurel Vlaicu, Hermann Oberth and Dumnitru Prunariu.

  12. Cosmic ray impact on extrasolar earth-like planets in close-in habitable zones.

    PubMed

    Griessmeier, J-M; Stadelmann, A; Motschmann, U; Belisheva, N K; Lammer, H; Biernat, H K

    2005-10-01

    Because of their different origins, cosmic rays can be subdivided into galactic cosmic rays and solar/stellar cosmic rays. The flux of cosmic rays to planetary surfaces is mainly determined by two planetary parameters: the atmospheric density and the strength of the internal magnetic moment. If a planet exhibits an extended magnetosphere, its surface will be protected from high-energy cosmic ray particles. We show that close-in extrasolar planets in the habitable zone of M stars are synchronously rotating with their host star because of the tidal interaction. For gravitationally locked planets the rotation period is equal to the orbital period, which is much longer than the rotation period expected for planets not subject to tidal locking. This results in a relatively small magnetic moment. We found that an Earth-like extrasolar planet, tidally locked in an orbit of 0.2 AU around an M star of 0.5 solar masses, has a rotation rate of 2% of that of the Earth. This results in a magnetic moment of less than 15% of the Earth's current magnetic moment. Therefore, close-in extrasolar planets seem not to be protected by extended Earth-like magnetospheres, and cosmic rays can reach almost the whole surface area of the upper atmosphere. Primary cosmic ray particles that interact with the atmosphere generate secondary energetic particles, a so-called cosmic ray shower. Some of the secondary particles can reach the surface of terrestrial planets when the surface pressure of the atmosphere is on the order of 1 bar or less. We propose that, depending on atmospheric pressure, biological systems on the surface of Earth-like extrasolar planets at close-in orbital distances can be strongly influenced by secondary cosmic rays.

  13. Galactic Cosmic Rays: From Earth to Sources

    NASA Technical Reports Server (NTRS)

    Brandt, Theresa J.

    2012-01-01

    For nearly 100 years we have known that cosmic rays come from outer space, yet proof of their origin, as well as a comprehensive understanding of their acceleration, remains elusive. Direct detection of high energy (up to 10(exp 15)eV), charged nuclei with experiments such as the balloon-born, antarctic Trans-Iron Galactic Element Recorder (TIGER) have provided insight into these mysteries through measurements of cosmic ray abundances. The abundance of these rare elements with respect to certain intrinsic properties suggests that cosmic rays include a component of massive star ejecta. Supernovae and their remnants (SNe & SNRs), often occurring at the end of a massive star's life or in an environment including massive star material, are one of the most likely candidates for sources accelerating galactic comic ray nuclei up to the requisite high energies. The Fermi Gamma-ray Space Telescope Large Area Detector (Fermi LAT) has improved our understanding of such sources by widening the window of observable energies and thus into potential sources' energetic processes. In combination with multiwavelength observations, we are now better able to constrain particle populations (often hadron-dominated at GeV energies) and environmental conditions, such as the magnetic field strength. The SNR CTB 37A is one such source which could contribute to the observed galactic cosmic rays. By assembling populations of SNRs, we will be able to more definitively define their contribution to the observed galactic cosmic rays, as well as better understand SNRs themselves. Such multimessenger studies will thus illuminate the long-standing cosmic ray mysteries, shedding light on potential sources, acceleration mechanisms, and cosmic ray propagation.

  14. Sources of cosmic dust in the Earth's atmosphere

    NASA Astrophysics Data System (ADS)

    Carrillo-Sánchez, J. D.; Nesvorný, D.; Pokorný, P.; Janches, D.; Plane, J. M. C.

    2016-12-01

    There are four known sources of dust in the inner solar system: Jupiter Family comets, asteroids, Halley Type comets, and Oort Cloud comets. Here we combine the mass, velocity, and radiant distributions of these cosmic dust populations from an astronomical model with a chemical ablation model to estimate the injection rates of Na and Fe into the Earth's upper atmosphere, as well as the flux of cosmic spherules to the surface. Comparing these parameters to lidar observations of the vertical Na and Fe fluxes above 87.5 km, and the measured cosmic spherule accretion rate at South Pole, shows that Jupiter Family Comets contribute (80 ± 17)% of the total input mass (43 ± 14 t d-1), in good accord with Cosmic Background Explorer and Planck observations of the zodiacal cloud.

  15. Sources of cosmic dust in the Earth's atmosphere.

    PubMed

    Carrillo-Sánchez, J D; Nesvorný, D; Pokorný, P; Janches, D; Plane, J M C

    2016-12-16

    There are four known sources of dust in the inner solar system: Jupiter Family comets, asteroids, Halley Type comets, and Oort Cloud comets. Here we combine the mass, velocity, and radiant distributions of these cosmic dust populations from an astronomical model with a chemical ablation model to estimate the injection rates of Na and Fe into the Earth's upper atmosphere, as well as the flux of cosmic spherules to the surface. Comparing these parameters to lidar observations of the vertical Na and Fe fluxes above 87.5 km, and the measured cosmic spherule accretion rate at South Pole, shows that Jupiter Family Comets contribute (80 ± 17)% of the total input mass (43 ± 14 t d -1 ), in good accord with Cosmic Background Explorer and Planck observations of the zodiacal cloud.

  16. Sources of cosmic dust in the Earth's atmosphere

    PubMed Central

    Carrillo‐Sánchez, J. D.; Nesvorný, D.; Pokorný, P.; Janches, D.

    2016-01-01

    Abstract There are four known sources of dust in the inner solar system: Jupiter Family comets, asteroids, Halley Type comets, and Oort Cloud comets. Here we combine the mass, velocity, and radiant distributions of these cosmic dust populations from an astronomical model with a chemical ablation model to estimate the injection rates of Na and Fe into the Earth's upper atmosphere, as well as the flux of cosmic spherules to the surface. Comparing these parameters to lidar observations of the vertical Na and Fe fluxes above 87.5 km, and the measured cosmic spherule accretion rate at South Pole, shows that Jupiter Family Comets contribute (80 ± 17)% of the total input mass (43 ± 14 t d−1), in good accord with Cosmic Background Explorer and Planck observations of the zodiacal cloud. PMID:28275286

  17. Water, air, Earth and cosmic radiation.

    PubMed

    Bassez, Marie-Paule

    2015-06-01

    In the context of the origin of life, rocks are considered mainly for catalysis and adsorption-desorption processes. Here it is shown how some rocks evolve in energy and might induce synthesis of molecules of biological interest. Radioactive rocks are a source of thermal energy and water radiolysis producing molecular hydrogen, H2. Mafic and ultramafic rocks evolve in water and dissolved carbon dioxide releasing thermal energy and H2. Peridotites and basalts contain ferromagnesian minerals which transform through exothermic reactions with the generation of heat. These reactions might be triggered by any heating process such as radioactive decay, hydrothermal and subduction zones or post-shock of meteorite impacts. H2 might then be generated from endothermic hydrolyses of the ferromagnesian minerals olivine and pyroxene. In both cases of mafic and radioactive rocks, production of CO might occur through high temperature hydrogenation of CO2. CO, instead of CO2, was proven to be necessary in experiments synthesizing biological-type macromolecules with a gaseous mixture of CO, N2 and H2O. In the geological context, N2 is present in the environment, and the activation source might arise from cosmic radiation and/or radionuclides. Ferromagnesian and radioactive rocks might consequently be a starting point of an hydrothermal chemical evolution towards the abiotic formation of biological molecules. The two usually separate worlds of rocks and life are shown to be connected through molecular and thermodynamic chemical evolution. This concept has been proposed earlier by the author (Bassez J Phys: Condens Matter 15:L353-L361, 2003, 2008a, 2008b; Bassez Orig Life Evol Biosph 39(3-4):223-225, 2009; Bassez et al. 2011; Bassez et al. Orig Life Evol Biosph 42(4):307-316, 2012, Bassez 2013) without thermodynamic details. This concept leads to signatures of prebiotic chemistry such as radionuclides and also iron and magnesium carbonates associated with serpentine and/or talc

  18. The influence of cosmic radiation on the properties of different polymers

    NASA Astrophysics Data System (ADS)

    Major, Andrea Adamne; Boja, David

    2017-10-01

    During our research we investigated the influence of cosmic radiation on the properties of different polymers. Polypropylene, polyamide 6.6 and polycarbonate were used as raw materials. Test pieces were injection molded. The test pieces were "flying" at different heights (on Earth, at 5500 m, at 12000 m). Thermal properties were investigated: DSC and TGA. We found that cosmic relay influences change in the thermal properties of polypropylene, polyamide 6.6 and polycarbonate.

  19. Cosmic acceleration of Earth and the Moon by dark matter

    NASA Technical Reports Server (NTRS)

    Nordtvedt, Kenneth L.

    1994-01-01

    In order to test the hypothesis that the gravitational interaction between our Galaxy's dark matter and the ordinary matter in Earth and the Moon might not fulfill the equivalence principle (universality of free fall), we consider the pertinent perturbation of the lunar orbit -- a sidereal month period range oscillation resulting from a spatially fixed polarization of the orbit. Lunar laser ranging (LLR) data can measure this sidereal perturbation to an accuracy equal to or better than its existing measurement of the synodic month period range oscillation amplitude (+/- 3 cm) which has been used for testing whether Earth and the Moon accelerate at equal rates toward the Sun. Because of the slow precession rate of the Moon's perigree (8.9 yr period), the lunar orbit is particularly sensitive to a cosmic acceleration; the LLR fit of the orbit places an upper limit of 10(exp -13) cm/sq. s for any cosmic differential acceleration between Earth (Fe) and the Moon (silicates). This is 10(exp -5) of the total galactic acceleration of the solar system, of which, it has been suggested, a large portion is produced by dark matter.

  20. Bioeffectiveness of Cosmic Rays Near the Earth Surface

    NASA Astrophysics Data System (ADS)

    Belisheva, N. K.

    2014-10-01

    Experimental studies of the dynamics of morphological and functional state of the diverse biosystems (microflora, plant Maranta leuconeura «Fascinator», cell cultures, human peripheral blood, the human body ) have shown that geocosmical agents modulated the functional state of biological systems Belisheva 2006; Belisheva et all 2007 ) . First time on the experimental data showed the importance of the increase in the fluxes of solar cosmic rays (CRs ) with high energies (Belisheva et all 2002; 2012; Belisheva, Lammer, Biernat, 2004) and galactic cosmic ray variations (Belisheva et al, 2005; 2006; Vinnichenko Belisheva, 2009 ) near the Earth surface for the functional state of biosystems. The evidence of the presence of the particles with high bioeffectiveness in the secondary cosmic rays was obtained by simulating the particle cascades in the atmosphere, performed by using Geant4 (Planetocosmics, based on the Monte Carlo code (Maurchev et al, 2011), and experimental data, where radiobiological effects of cosmic rays were revealed. Modeling transport of solar protons through the Earth's atmosphere, taking into account the angular and energy distributions of secondary particles in different layers of the atmosphere, allowed us to estimate the total neutron flux during three solar proton events, accompanied by an increase in the intensity of the nucleon component of secondary cosmic rays - Ground Level Enhancement GLE (43, 44, 45) in October 1989 (19, 22, 24 October). The results obtained by simulation were compared with the data of neutron monitors and balloon measurements made during solar proton events. Confirmation of the neutron fluxes near the Earth surface during the GLE (43, 44, 45) were obtained in the experiments on the cellular cultures (Belisheva et al. 2012). A direct evidence of biological effects of CR has been demonstrated in experiments with three cellular lines growing in culture during three events of Ground Level Enhancement (GLEs) in the

  1. Cosmic Dust and the Earth's Atmosphere (Vilhelm Bjerknes Medal Lecture)

    NASA Astrophysics Data System (ADS)

    Plane, John M. C.

    2017-04-01

    Cosmic dust particles are produced in the solar system from the sublimation of comets as they orbit close to the sun, and also from collisions between asteroids in the belt between Mars and Jupiter. Dust particles enter the atmosphere at hyperthermal velocities (11 - 72 km s-1), and ablate at heights between 80 and 120 km in the mesosphere/lower thermosphere (MLT). The resulting metallic vapours (Fe, Mg, Si and Na etc.) then oxidize and recondense to form nm-size particles, termed "meteoric smoke particles (MSPs)". MSPs are too small to sediment downwards and so are transported by the general circulation of the atmosphere, taking roughly 4 years to reach the surface. Smoke particles play a potentially important role as condensation nuclei of noctilucent ice clouds in the mesosphere, and polar stratospheric clouds in the lower stratosphere, where they also facilitate freezing of the clouds. There are also potential implications for climate, as the input of bio-available cosmic Fe in the Southern Ocean can increase biological productivity and stimulate CO2 drawdown from the atmosphere. However, current estimates of the magnitude of the cosmic dust mass input rate into the Earth's atmosphere range from 2 to over 200 tonnes per day, depending on whether the measurements are made in space, in the middle atmosphere, or in polar ice cores. This nearly 2 order-of-magnitude discrepancy indicates that there must be serious flaws in the interpretation of observations that have been used to make the estimates. Furthermore, given this degree of uncertainty, the significance of these potential atmospheric impacts remains speculative. In this lecture I will describe the results of a large study designed to determine the size of the cosmic dust input rate using a self-consistent treatment of cosmic dust from the outer solar system to the Earth's surface. An astronomical model which tracks the evolution of dust from various sources into the inner solar system was combined with a

  2. The Transition from Earth-Centred Biology to Cosmic Life

    NASA Astrophysics Data System (ADS)

    Wickramasinghe, N. Chandra; Tokoro, Gensuke; Wainwright, Milton

    A paradigm shift with potentially profound implications has been taking place over the past 3 decades. The convergence of research in diverse disciplines points to life being a cosmic phenomenon. A near-infinite information content of life appears to have evolved on a cosmological scale -- over vast distances, and enormous spans of time. It appears highly unlikely that life could have emerged from chemicals in "some warm little pond" on the Earth; in contrast we maintain that every species of life on the Earth, including Homo sapiens, is in essence the result of an assembly of cosmologically derived viral genes. The ingress of such genes that continues to the present day led to their accommodation within the genomes of evolving lineages, sifted according to the "natural processes of selection", a mechanism first enunciated by Patrick Matthews and later used by Darwin. The evidence for this point of view has now grown to the point where we believe, it will soon need to be accepted by the majority of the scientific community. This is particularly critical, since we suggest that new diseases capable of threatening Man's existence could arrive to Earth from space. Moreover, we need to understand that we must live in harmony with the Earth and its ever-changing biosphere if we are to coexist with it.

  3. Rare Earth or Cosmic Zoo: Testing the Frequency of Complex Life in the Universe

    NASA Astrophysics Data System (ADS)

    Bains, W.; Schulze-Makuch, D.

    2017-02-01

    We propose how to test between two major hypotheses about the frequency of life in the universe (Rare Earth and Cosmic Zoo) using future remote sensing capabilities targeted at exoplanets and site visits of planetary bodies in our solar system.

  4. Cosmic rays and other space phenomena dangerous for the Earth's civilization: Foundation of cosmic ray warning system and beginning steps

    NASA Astrophysics Data System (ADS)

    Lev, Dorman

    2016-07-01

    difference between consequences Alerts became much smaller than errors. In our report "Cosmic Rays and other Space Weather Effects Influenced on Satellites Operation, Technologies, Biosphere and People Health" it was shown that very important element of Space Weather, influenced on satellites operation, technologies, and people health are strong magnetic storms, accompanied usually by CR Forbush effects. We discuss here on the possibility to include in the "Cosmic Ray Warning System" possibility to forecast this phenomenon, also dangerous for the Earth's Civilization. In the report "Cosmic Rays and other Space Phenomena Influenced on the Earth's Climate" on this Conference it was shown that very big changes in climate, dangerous for the Earth's Civilization, are caused by interactions of Solar system with molecular-dust clouds (caused the Great Ice Periods during many thousand years). Very dangerous for the Earth's Civilization are also nearby supernova explosions with great influence on biosphere and climate. We show that by CR data in the frame of "Cosmic Ray Warning System" is possible to forecast for many years before starting these dangerous phenomena, so the Earth's Civilization will have enough time for preparing to the new type of life. For this forecasting we need to add to the "Cosmic Ray Warning System" in near future several CR stations for continue measuring CR with much higher energies (1013 - 1014 eV). We hope to organize the mostly automatic working "Cosmic Ray Warning System" in cooperation with Azerbaijan, Israel, and many CR stations in the World. The Project will be open for any country and organizations (ESA, NASA and so on) and will be start as soon as possible. In the first 3 - 5 years we hope that forecasting of radiation hazards will be made fully automatically as it was described in this report. In the next 5-10 years the Project will be expanded for forecasting dangerous magnetic storms (in this case we need to use also muon telescopes data), and

  5. Heliospheric influence on the anisotropy of TeV cosmic rays

    DOE PAGES

    Zhang, Ming; Zuo, Pingbing; Pogorelov, Nikolai

    2014-06-26

    This article provides a theory of using Liouville's theorem to map the anisotropy of TeV cosmic rays seen at Earth using the particle distribution function in the local interstellar medium (LISM). The ultimate source of cosmic ray anisotropy is the energy, pitch angle, and spatial dependence of the cosmic ray distribution function in the LISM. Because young nearby cosmic ray sources can make a special contribution to the cosmic ray anisotropy, the anisotropy depends on the source age, distance and magnetic connection, and particle diffusion of these cosmic rays, all of which make the anisotropy sensitive to the particle energy.more » When mapped through the magnetic and electric field of a magnetohydrodynamic model heliosphere, the large-scale dipolar and bidirectional interstellar anisotropy patterns become distorted if they are seen from Earth, resulting in many small structures in the observations. Best fits to cosmic ray anisotropy measurements have allowed us to estimate the particle density gradient and pitch angle anisotropies in the LISM. It is found that the heliotail, hydrogen deflection plane, and the plane perpendicular to the LISM magnetic field play a special role in distorting cosmic ray anisotropy. These features can lead to an accurate determination of the LISM magnetic field direction and polarity. The effects of solar cycle variation, the Sun's coronal magnetic field, and turbulence in the LISM and heliospheric magnetic fields are minor but clearly visible at a level roughly equal to a fraction of the overall anisotropy amplitude. Lastly, the heliospheric influence becomes stronger at lower energies. Below 1 TeV, the anisotropy is dominated by small-scale patterns produced by disturbances in the heliosphere.« less

  6. Heliospheric influence on the anisotropy of TeV cosmic rays

    SciTech Connect

    Zhang, Ming; Zuo, Pingbing; Pogorelov, Nikolai, E-mail: mzhang@fit.edu

    2014-07-20

    This paper provides a theory of using Liouville's theorem to map the anisotropy of TeV cosmic rays seen at Earth using the particle distribution function in the local interstellar medium (LISM). The ultimate source of cosmic ray anisotropy is the energy, pitch angle, and spatial dependence of the cosmic ray distribution function in the LISM. Because young nearby cosmic ray sources can make a special contribution to the cosmic ray anisotropy, the anisotropy depends on the source age, distance and magnetic connection, and particle diffusion of these cosmic rays, all of which make the anisotropy sensitive to the particle energy.more » When mapped through the magnetic and electric field of a magnetohydrodynamic model heliosphere, the large-scale dipolar and bidirectional interstellar anisotropy patterns become distorted if they are seen from Earth, resulting in many small structures in the observations. Best fits to cosmic ray anisotropy measurements have allowed us to estimate the particle density gradient and pitch angle anisotropies in the LISM. It is found that the heliotail, hydrogen deflection plane, and the plane perpendicular to the LISM magnetic field play a special role in distorting cosmic ray anisotropy. These features can lead to an accurate determination of the LISM magnetic field direction and polarity. The effects of solar cycle variation, the Sun's coronal magnetic field, and turbulence in the LISM and heliospheric magnetic fields are minor but clearly visible at a level roughly equal to a fraction of the overall anisotropy amplitude. The heliospheric influence becomes stronger at lower energies. Below 1 TeV, the anisotropy is dominated by small-scale patterns produced by disturbances in the heliosphere.« less

  7. Cosmic Rays in the Earth's Atmosphere and Underground

    NASA Astrophysics Data System (ADS)

    Dorman, Lev I.

    2004-08-01

    This book consists of four parts. In the first part (Chapters 1-4) a full overview is given of the theoretical and experimental basis of Cosmic Ray (CR) research in the atmosphere and underground for Geophysics and Space Physics; the development of CR research and a short history of many fundamental discoveries, main properties of primary and secondary CR, methods of transformation of CR observation data in the atmosphere and underground to space, and the experimental basis of CR research underground and on the ground, on balloons and on satellites and space probes. The second part (Chapters 5-9) is devoted to the influence of atmospheric properties on CR, so called CR meteorological effects; pressure, temperature, humidity, snow, wind, gravitation, and atmospheric electric field effects. The inverse problem - the influence of CR properties on the atmosphere and atmospheric processes is considered in the third part (Chapters 10-14); influence on atmospheric, nuclear and chemical compositions, ionization and radio-wave propagation, formation of thunderstorms and lightning, clouds and climate change. The fourth part (Chapters 15-18) describes many realized and potential applications of CR research in different branches of Science and Technology; Meteorology and Aerodrome Service, Geology and Geophysical Prospecting, Hydrology and Agricultural Applications, Archaeology and Medicine, Seismology and Big Earthquakes Forecasting, Space Weather and Environment Monitoring/Forecasting. The book ends with a list providing more than 1,500 full references, a discussion on future developments and unsolved problems, as well as object and author indices. This book will be useful for experts in different branches of Science and Technology, and for students to be used as additional literature to text-books.

  8. Propagation of Galactic cosmic rays: the influence of anisotropic diffusion

    NASA Astrophysics Data System (ADS)

    AL-Zetoun, A.; Achterberg, A.

    2018-06-01

    We consider the anisotropic diffusion of cosmic rays in the large-scale Galactic magnetic field, where diffusion along the field and diffusion across the field proceeds at different rates. To calculate this diffusion, we use stochastic differential equations to describe the cosmic ray propagation, solving these numerically. The Galactic magnetic field is described using the Jansson-Farrar model for the Galactic magnetic field. In this paper, we study the influence of perpendicular diffusion on the residence time of cosmic rays in the Galaxy. This provides an estimate for the influence of anisotropic diffusion on the residence time and the amount of matter (grammage) that a typical cosmic ray traverses during its residence in the Galaxy.

  9. The Cosmic Habitat for Earth-Life and the Issue of Sustainable Development

    NASA Astrophysics Data System (ADS)

    Piątek, Zdzisława

    2017-12-01

    The subjects under consideration here are the philosophical consequences arising as the cosmic dimension to ecology is taken into account. If the habitat for Earthlife is a part of the cosmic environment, then cosmology and astrophysics become a part of ecology. The human species is furthermore a participant in a vast process of cosmic evolution, with sustainable-development strategy thus defi ning the conditions for - and time needed to achieve - a technological civilisation allowing Earth-life to be evacuated to another part of the galaxy as and when the further existence of life on this planet becomes (or threatens to become) an impossibility. In the context of such a cosmic perspective, the value ascribable to our scientifi c and technological civilisation (and future versions thereof) changes, given that only this kind of civilisation offers a chance for Earth-life to persist in an extra-terrestrial environment.

  10. The Influence of COSMIC Satellite Data on Regional Analysis

    NASA Astrophysics Data System (ADS)

    Kuo, Y.

    2006-12-01

    The atmospheric limb sounding technique making use of radio signals transmitted by the Global Position System (GPS) has emerged as a promising approach for global atmospheric measurements. As demonstrated by the proof-of-concept GPS Meteorology (GPS/MET) experiment and more recently by the CHAMP and SAC-C missions, the GPS radio occultation (RO) sounding data are of high accuracy and high vertical resolution. On 15 April 2006, the joint U.S.-Taiwan COSMIC/FORMOSAT-3 mission, a constellation of six microsatellites, was launched from the Vandenberg Air Force Base. These satellites are being deployed to their final orbits, which would take about a year. During the early phase of the deployment, the satellites are closely located. This offers a unique opportunity to examine the precision of the GPS RO measurements. The COSMIC data are available in near real-time for global weather analysis and prediction and for climate monitoring. Currently, COSMIC is producing approximately 1300 GPS RO soundings per day at the end of August 2006. This number will be increased as the satellites are further separated through the deployment process. Radio occultation measures phase and amplitude of the microwave signals emitted from GPS. These signals are inverted to obtain profiles of signal bending, atmospheric refractivity, pressure temperature and water vapor. The main objective of the COSMIC/FORMOSAT-3 mission is to demonstrate the value of these radio occultation products for weather forecasting, climate monitoring, ionospheric research and space weather prediction. This presentation will provide an overview of the COSMIC/FORMOSAT-3 program. We will present results on the influence of COSMIC data on the regional analysis over the data void regions, particularly over the tropics and high latitudes. For further information on the COSMIC/FORMOSAT-3, please refer to http://www.cosmic.ucar.edu/.

  11. SOLAR COSMIC RAYS AND SOFT RADIATION OBSERVED AT 5,000,000 KILOMETERS FROM EARTH

    SciTech Connect

    Arnoldy, R.L.; Hoffman, R.A.; Winckler, J.R.

    1960-09-01

    During the period Mar. 27 to Apr. 6, 1960, the integrating ionization chamber and Geiger counter in Pioneer V detected solar cosmic rays and some soft- radiation effects associated with a high level of solar activity. The space probe was 5 x 10/sup 6/ km from the earth, approximately in the plane of the ecliptic, and located somewhat behind the sunearth radius toward the sun. The solar activity was associated with McMath plage region 5615 and was characterized by numerous flares of all sizes, large loops and surge prominences, and strong emission over a wide range of frequencies. On Mar.more » 31 at 0800 UT, a severe geomagnetic storm began on earth accompanied by major earth-current disturbances, a complete blackout of the North Atlantic communications channel, and auroral displays. At the same time, a large Forbush decrease occurred in the galactic cosmic radiation. An intense series of balloon flights was conducted to record the counting-rate increases at high altitudes due to solar cosmic rays and auroral x rays. Explorer VII showed substantial changes in the radiation belts and detected the solar cosmic rays. The observations of Pioneer V are summarized and compared to the findings of Explorer VII for the same period. (B.O.G.)« less

  12. COMPARISON OF COSMIC-RAY ENVIRONMENTS ON EARTH, MOON, MARS AND IN SPACECARFT USING PHITS.

    PubMed

    Sato, Tatsuhiko; Nagamatsu, Aiko; Ueno, Haruka; Kataoka, Ryuho; Miyake, Shoko; Takeda, Kazuo; Niita, Koji

    2017-09-29

    Estimation of cosmic-ray doses is of great importance not only in aircrew and astronaut dosimetry but also in evaluation of background radiation exposure to public. We therefore calculated the cosmic-ray doses on Earth, Moon and Mars as well as inside spacecraft, using Particle and Heavy Ion Transport code System PHITS. The same cosmic-ray models and dose conversion coefficients were employed in the calculation to properly compare between the simulation results for different environments. It is quantitatively confirmed that the thickness of physical shielding including the atmosphere and soil of the planets is the most important parameter to determine the cosmic-ray doses and their dominant contributors. The comparison also suggests that higher solar activity significantly reduces the astronaut doses particularly for the interplanetary missions. The information obtained from this study is useful in the designs of the future space missions as well as accelerator-based experiments dedicated to cosmic-ray research. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Searching for a shadow biosphere on Earth as a test of the 'cosmic imperative'.

    PubMed

    Davies, P C W

    2011-02-13

    Estimates for the number of communicating civilizations in the galaxy, based on the so-called Drake equation, are meaningless without a plausible estimate for the probability that life will emerge on an Earth-like planet. In the absence of a theory of the origin of life, that number can be anywhere from 0 to 1. Distinguished scientists have been known to argue that life on Earth is a freak accident, unique in the observable universe and, conversely, that life is almost bound to arise in the course of time, given Earth-like conditions. De Duve, adopting the latter position, coined the phrase that 'life is a cosmic imperative'. De Duve's position would be immediately verified if we were to discover a second sample of life that we could be sure arose from scratch independently of known life. Given the current absence of evidence for life beyond Earth, the best way to test the hypothesis of the cosmic imperative is to see whether terrestrial life began more than once. If it did, it is possible that descendants of a second genesis might be extant, forming a sort of 'shadow biosphere' existing alongside, or perhaps interpenetrating, the known biosphere. I outline a strategy to detect the existence of such a shadow biosphere.

  14. Earthing the Human Body Influences Physiologic Processes

    PubMed Central

    Sokal, Karol

    2011-01-01

    Abstract Objectives This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments Five (5) experiments are presented: experiment 1—effect of earthing on calcium–phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2—effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3—effect of earthing on thyroid function (N = 12); experiment 4—effect of earthing on glucose concentration (N = 12); experiment 5—effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Results Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Conclusions Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium–phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems. PMID:21469913

  15. Earthing the human body influences physiologic processes.

    PubMed

    Sokal, Karol; Sokal, Pawel

    2011-04-01

    This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

  16. The problems of cosmic ray particle simulation for the near-Earth orbital and interplanetary flight conditions.

    PubMed

    Nymmik, R A

    1999-10-01

    A wide range of the galactic cosmic ray and SEP event flux simulation problems for the near-Earth satellite and manned spacecraft orbits and for the interplanetary mission trajectories are discussed. The models of the galactic cosmic ray and SEP events in the Earth orbit beyond the Earth's magnetosphere are used as a basis. The particle fluxes in the near-Earth orbits should be calculated using the transmission functions. To calculate the functions, the dependences of the cutoff rigidities on the magnetic disturbance level and on magnetic local time have to be known. In the case of space flights towards the Sun and to the boundary of the solar system, particular attention is paid to the changes in the SEP event occurrence frequency and size. The particle flux gradients are applied in this case to galactic cosmic ray fluxes.

  17. Control of the Earth's electric field intensity through solar wind modulation of galactic cosmic radiation: Support for a proposed atmospheric electrical sun-weather mechanism

    NASA Technical Reports Server (NTRS)

    Markson, R.

    1980-01-01

    The ionospheric potential and galactic cosmic radiation, found to be inversely correlated with the solar wind velocity are examined as being germane to weather modification. Since the ionospheric potential is proportional to the fair weather electric field intensity and cosmic radiation is the dominant source of atmospheric ionization, it is concluded that the Earth's overall electric field varies in phase with atmospheric ionization and that the latter is modulated by the solar wind. A proposed mechanism, in which solar control of ionizing radiation influences atmospheric electrification and thus possibly cloud physical processes is discussed. An experimental approach to critically test the proposed mechanism through comparison of the temporal variation of the Earth's electric field with conditions in the interplanetary medium is outlined.

  18. How large is the cosmic dust flux into the Earth's atmosphere?

    NASA Astrophysics Data System (ADS)

    Plane, John; Janches, Diego; Gomez-Martin, Juan Carlos; Bones, David; Diego Carrillo-Sanchez, Juan; James, Sandy; Nesvorny, David; Pokorny, Petr

    2016-07-01

    Cosmic dust particles are produced in the solar system from the sublimation of comets as they orbit close to the sun, and also from collisions between asteroids in the belt between Mars and Jupiter. Current estimates of the magnitude of the cosmic dust input rate into the Earth's atmosphere range from 2 to well over 100 tons per day, depending on whether the measurements are made in space, in the middle atmosphere, or at the surface in polar ice cores. This nearly 2 order-of-magnitude discrepancy indicates that there are serious flaws in the interpretation of observations that have been used to make the estimates. Dust particles enter the atmosphere at hyperthermal velocities (11 - 72 km s ^{-1}), and mostly ablate at heights between 80 and 120 km in a region of the atmosphere known as the mesosphere/lower thermosphere (MLT). The resulting metal vapours (Fe, Mg, Si and Na etc.) then oxidize and recondense to form nm-size particles, termed "meteoric smoke". These particles are too small to sediment downwards. Instead, they are transported by the general circulation of the atmosphere, taking roughly 5 years to reach the surface. There is great interest in the role smoke particles play as condensation nuclei of noctilucent ice clouds in the mesosphere, and polar stratospheric clouds in the lower stratosphere. Various new estimates of the dust input will be discussed. The first is from a zodiacal dust cloud model which predicts that more than 90% of the dust entering the atmosphere comes from Jupiter Family Comets; this model is constrained by observations of the zodiacal cloud using the IRAS, COBE and Planck satellites. The cometary dust is predicted to mostly be in a near-prograde orbit, entering the atmosphere with an average velocity around 14 km s ^{-1}. The total dust input should then be about 40 t d ^{-1}. However, relatively few of these particles are observed, even by the powerful Arecibo 430 MHz radar. Coupled models of meteoroid differential ablation

  19. Using the information of cosmic rays to predict influence epidemic

    NASA Astrophysics Data System (ADS)

    Yu, Z. D.

    1985-08-01

    A correlation between the incidence of influenza pandemics and increased cosmic ray activity is made. A correlation is also made between the occurrence of these pandemics and the appearance of bright novae, e.g., Nova Eta Car. Four indices based on increased cosmic ray activity and novae are proposed to predict future influenza pandemics and viral antigenic shifts.

  20. Using the information of cosmic rays to predict influence epidemic

    NASA Technical Reports Server (NTRS)

    Yu, Z. D.

    1985-01-01

    A correlation between the incidence of influenza pandemics and increased cosmic ray activity is made. A correlation is also made between the occurrence of these pandemics and the appearance of bright novae, e.g., Nova Eta Car. Four indices based on increased cosmic ray activity and novae are proposed to predict future influenza pandemics and viral antigenic shifts.

  1. Transient Weakening of Earth's Magnetic Shield Probed by a Cosmic Ray Burst.

    PubMed

    Mohanty, P K; Arunbabu, K P; Aziz, T; Dugad, S R; Gupta, S K; Hariharan, B; Jagadeesan, P; Jain, A; Morris, S D; Rao, B S; Hayashi, Y; Kawakami, S; Oshima, A; Shibata, S; Raha, S; Subramanian, P; Kojima, H

    2016-10-21

    The GRAPES-3 tracking muon telescope in Ooty, India measures muon intensity at high cutoff rigidities (15-24 GV) along nine independent directions covering 2.3 sr. The arrival of a coronal mass ejection on 22 June 2015 18:40 UT had triggered a severe G4-class geomagnetic storm (storm). Starting 19:00 UT, the GRAPES-3 muon telescope recorded a 2 h high-energy (∼20  GeV) burst of galactic cosmic rays (GCRs) that was strongly correlated with a 40 nT surge in the interplanetary magnetic field (IMF). Simulations have shown that a large (17×) compression of the IMF to 680 nT, followed by reconnection with the geomagnetic field (GMF) leading to lower cutoff rigidities could generate this burst. Here, 680 nT represents a short-term change in GMF around Earth, averaged over 7 times its volume. The GCRs, due to lowering of cutoff rigidities, were deflected from Earth's day side by ∼210° in longitude, offering a natural explanation of its night-time detection by the GRAPES-3. The simultaneous occurrence of the burst in all nine directions suggests its origin close to Earth. It also indicates a transient weakening of Earth's magnetic shield, and may hold clues for a better understanding of future superstorms that could cripple modern technological infrastructure on Earth, and endanger the lives of the astronauts in space.

  2. Linear Energy Transfer (LET) spectra of cosmic radiation in low Earth orbit

    NASA Technical Reports Server (NTRS)

    Parnell, T. A.; Watts, J. W., Jr.; Akopova, A. B.; Magradze, N. V.; Dudkin, V. E.; Kovalev, E. E.; Potapov, Yu. V.; Benton, E. V.; Frank, A. L.; Benton, E. R.

    1995-01-01

    Integral linear energy transfer (LET) spectra of cosmic radiation (CR) particles were measured on five Cosmos series spacecraft in low Earth orbit (LEO). Particular emphasis is placed on results of the Cosmos 1887 biosatellite which carried a set of joint U.S.S.R.-U.S.A. radiation experiments involving passive detectors that included thermoluminescent detectors (TLD's), plastic nuclear track detectors (PNTD's), fission foils, nuclear photo-emulsions, etc. which were located both inside and outside the spacecraft. Measured LET spectra are compared with those theoretically calculated. Results show that there is some dependence of LET spectra on orbital parameters. The results are used to estimate the CR quality factor (QF) for the COSMOS 1887 mission.

  3. Penetration boundary of solar cosmic rays into the earth's magnetosphere during magnetically quiet times

    SciTech Connect

    Biryukov, A.S.; Ivanova, T.A.; Kovrygina, L.M.

    1984-05-01

    Data is used from the satellites Interkosmos-17 and Kosmos-900 to determine penetration boundaries at high latitudes in the earth's magnetosphere. Considered are the results of observations of the penetration boundary of solar cosmic ray (SCR) protons and electrons during an SCR increase on November 22-25, 1977. The position of the SCR penetration boundary during a single increase at practically all values of MLT in quiet conditions is examined. Magnetospheric structure is determined in the region of closed drift shells where the magnetic field is asymmetric. The authors can estimate how the solar wind pressure affects the magnetosphere by using datamore » on the penetration boundaries of solar protons obtained during quiet geomagnetic conditions.« less

  4. Influence of hadron and atmospheric models on computation of cosmic ray ionization in the atmosphere-Extension to heavy nuclei

    NASA Astrophysics Data System (ADS)

    Mishev, A. L.; Velinov, P. I. Y.

    2014-12-01

    In the last few years an essential progress in development of physical models for cosmic ray induced ionization in the atmosphere is achieved. The majority of these models are full target, i.e. based on Monte Carlo simulation of an electromagnetic-muon-nucleon cascade in the atmosphere. Basically, the contribution of proton nuclei is highlighted, i.e. the contribution of primary cosmic ray α-particles and heavy nuclei to the atmospheric ionization is neglected or scaled to protons. The development of cosmic ray induced atmospheric cascade is sensitive to the energy and mass of the primary cosmic ray particle. The largest uncertainties in Monte Carlo simulations of a cascade in the Earth atmosphere are due to assumed hadron interaction models, the so-called hadron generators. In the work presented here we compare the ionization yield functions Y for primary cosmic ray nuclei, such as α-particles, Oxygen and Iron nuclei, assuming different hadron interaction models. The computations are fulfilled with the CORSIKA 6.9 code using GHEISHA 2002, FLUKA 2011, UrQMD hadron generators for energy below 80 GeV/nucleon and QGSJET II for energy above 80 GeV/nucleon. The observed difference between hadron generators is widely discussed. The influence of different atmospheric parametrizations, namely US standard atmosphere, US standard atmosphere winter and summer profiles on ion production rate is studied. Assuming realistic primary cosmic ray mass composition, the ion production rate is obtained at several rigidity cut-offs - from 1 GV (high latitudes) to 15 GV (equatorial latitudes) using various hadron generators. The computations are compared with experimental data. A conclusion concerning the consistency of the hadron generators is stated.

  5. Energetic particle influences in Earth's atmosphere

    NASA Astrophysics Data System (ADS)

    Aplin, Karen; Harrison, R. Giles; Nicoll, Keri; Rycroft, Michael; Briggs, Aaron

    2016-04-01

    Energetic particles from outer space, known as galactic cosmic rays, constantly ionise the entire atmosphere. During strong solar storms, solar energetic particles can also reach the troposphere and enhance ionisation. Atmospheric ionisation generates cluster ions. These facilitate current flow in the global electric circuit, which arises from charge separation in thunderstorms driven by meteorological processes. Energetic particles, whether solar or galactic in origin, may influence the troposphere and stratosphere through a range of different mechanisms, each probably contributing a small amount. Some of the suggested processes potentially acting over a wide spatial area in the troposphere include enhanced scavenging of charged aerosol particles, modification of droplet or droplet-droplet behavior by charging, and the direct absorption of infra-red radiation by the bending and stretching of hydrogen bonds inside atmospheric cluster-ions. As well as reviewing the proposed mechanisms by which energetic particles modulate atmospheric properties, we will also discuss new instrumentation for measurement of energetic particles in the atmosphere.

  6. Possible space weather influence on the Earth wheat prices

    NASA Astrophysics Data System (ADS)

    Pustil'Nik, L.; Yom Din, G.; Dorman, L.

    We present development of our study of possible influence of space weather modulated by cycle of solar activity on the price bursts in the Earth markets In our previous works 1 2 we showed that correspondent response may have place in the specific locations characterized by a high sensitivity of the weather cloudiness in particular to cosmic ray variation b risk zone agriculture c isolated wheat market with limited external supply of agriculture production We showed that in this situation we may wait specific price burst reaction on unfavorable phase of solar activity and space weather what lead to corresponding abnormalities in the local weather and next crop failure We showed that main types of manifestation of this connection are a Distribution of intervals between price bursts must be like to the distribution of intervals between correspondent extremes of solar activity minimums or maximums b price asymmetry between opposite states of solar activity price in the one type of activity state is systematically higher then in the opposite one We showed in our previous publications that this influence in interval distribution is detected with high reliability in Mediaeval England 1250-1700 both for wheat prices and price of consumables basket We showed that for period of Maunder Minimum price asymmetry of wheat prices observed all prices in minimum state of solar activity was higher the prices in the next maximum state We showed later that this price asymmetry had place in 20-th century in USA durum prices too In

  7. Cosmic dust flux on Earth inferred from the Concordia micrometeorite collection

    NASA Astrophysics Data System (ADS)

    Engrand, Cécile; Duprat, Jean; Dartois, Emmanuel; Godard, Marie; Delauche, Lucie

    2017-04-01

    The present extraterrestrial flux incoming to Earth is dominated by cosmic dust, i.e. micrometeorites in the 20-500 microns size range. Prior to atmospheric entry, the flux is estimated to ˜30 000 tons.yr-1 [1]. The proportion of this flux reaching the earth surface as dust particles is debated [e.g. 2]. Since 2000, we recover micrometeorites from ultraclean snow in the vicinity of the Dome C Concordia station in Antarctica. This region has a well-characterized and small precipitation rate (˜ 3.5 g of water per year) that allows collecting micrometeorites from large equivalent surfaces (> 100 m2.yrs) by sampling reasonable volumes of snow. The high efficiency and cleanliness of the collecting process at Dome C has enabled the recovery of several thousands of particles larger than ˜ 20 μm, constituting the Concordia micrometeorite collection [3]. The Concordia micrometeorites have a young terrestrial age of about 50 years. We characterized more than three thousand micrometeorites (both melted and unmelted particles) by secondary electron microscopy and classified them in the textural types defined in [4]. A preliminary flux value of 6,000 tons.yr-1 was given in [5] from the early Concordia collection examination. We now have better statistics to update this value. References: [1] Love S.G. and Brownlee D.E. (1993) Science 262, 550-553. [2] Peucker-Ehrenbrink B., et al. (2016) Elements 12, 191-196. [3] Duprat J., et al. (2007) Adv. Space Res. 39, 605-611. [4] Genge M.J., et al. (2008) Meteorit. Planet. Sci. 43, 497-515. [5] Duprat J., et al. (2006) Meteorit. Planet. Sci. 41 Suppl., A48 (#5239).

  8. THE COSMIC RAY EQUATOR FROM DATA OF THE SECOND SOVIET EARTH SATELLITE

    SciTech Connect

    Savenko, I.A.; Shavrin, P.I.; Nesterov, V.Ye.

    1962-11-01

    Determination of the geographical position of the line of minimum intensity of primary cosmic radiation (cosmic ray equator) makes is possible to study the structure of the geomagnetic field and to check theoretical and empirical approximations to this field. The minima of cosmic radiation intensity were determined by the second Soviet spaceship for 22 latitude curves obtained from various crossings in the region of the geographical equator. (W.D.M.)

  9. Fermi large area telescope observations of the cosmic-ray induced {gamma}-ray emission of the Earth's atmosphere

    SciTech Connect

    Abdo, A. A.; National Academy of Sciences, Washington, D.C. 20001; Ackermann, M.

    We report on measurements of the cosmic-ray induced {gamma}-ray emission of Earth's atmosphere by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The Large Area Telescope has observed the Earth during its commissioning phase and with a dedicated Earth limb following observation in September 2008. These measurements yielded {approx}6.4x10{sup 6} photons with energies >100 MeV and {approx}250 hours total live time for the highest quality data selection. This allows the study of the spatial and spectral distributions of these photons with unprecedented detail. The spectrum of the emission--often referred to as Earth albedo gamma-ray emission--has a power-lawmore » shape up to 500 GeV with spectral index {gamma}=2.79{+-}0.06.« less

  10. The influence of cosmic rays on the stability and large-scale dynamics of the interstellar medium

    NASA Astrophysics Data System (ADS)

    Kuznetsov, V. D.

    1986-06-01

    The diffusion-convection formulation is used to study the influence of galactic cosmic rays on the stability and dynamics of the interstellar medium which is supposedly kept in equilibrium by the gravitational field of stars. It is shown that the influence of cosmic rays on the growth rate of MHD instability depends largely on a dimensionless parameter expressing the ratio of the characteristic acoustic time scale to the cosmic-ray diffusion time. If this parameter is small, the cosmic rays will decelerate the build-up of instabilities, thereby stabilizing the system; in contrast, if the parameter is large, the system will be destabilized.

  11. Impact of a Cosmic Body into Earth's Ocean and the Generation of Large Tsunami Waves: Insight from Numerical Modeling

    NASA Astrophysics Data System (ADS)

    Wünnemann, K.; Collins, G. S.; Weiss, R.

    2010-12-01

    The strike of a cosmic body into a marine environment differs in several respects from impact on land. Oceans cover approximately 70% of the Earth's surface, implying not only that oceanic impact is a very likely scenario for future impacts but also that most impacts in Earth's history must have happened in marine environments. Therefore, the study of oceanic impact is imperative in two respects: (1) to quantify the hazard posed by future oceanic impacts, including the potential threat of large impact-generated tsunami-like waves, and (2) to reconstruct Earth's impact record by accounting for the large number of potentially undiscovered crater structures in the ocean crust. Reconstruction of the impact record is of crucial importance both for assessing the frequency of collision events in the past and for better predicting the probability of future impact. We summarize the advances in the study of oceanic impact over the last decades and focus in particular on how numerical models have improved our understanding of cratering in the oceanic environment and the generation of waves by impact. We focus on insight gleaned from numerical modeling studies into the deceleration of the projectile by the water, cratering of the ocean floor, the late stage modification of the crater due to gravitational collapse, and water resurge. Furthermore, we discuss the generation and propagation of large tsunami-like waves as a result of a strike of a cosmic body in marine environments.

  12. Concerning the use of multifunctional photometer - polarimeter for studying the invasion of cosmic bodies into the Earth's atmosphere

    NASA Astrophysics Data System (ADS)

    Geraimchuk, M. D.; Vidmachenko, A. P.; Nevodovskyi, P. V.; Steklov, O. F.

    2018-05-01

    Main astronomical observatory of the National Academy of Sciences of Ukraine together with the National Technical University of Ukraine "KPI" for many years working on the development of photometers-polarimeters for the study of cosmic bodies and Earth's atmosphere. We proposed an option of the development of a multipurpose panoramic photometer-polarimeter, which takes into account the shortcomings of the previous versions of the instrument and also allows for the registration of tracks of bolides, and study of their tails, and weak meteor phenomena.

  13. Cosmic rays: a review for astrobiologists.

    PubMed

    Ferrari, Franco; Szuszkiewicz, Ewa

    2009-05-01

    Cosmic rays represent one of the most fascinating research themes in modern astronomy and physics. Significant progress is being made toward an understanding of the astrophysics of the sources of cosmic rays and the physics of interactions in the ultrahigh-energy range. This is possible because several new experiments in these areas have been initiated. Cosmic rays may hold answers to a great number of fundamental questions, but they also shape our natural habitat and influence the radiation environment of our planet Earth. The importance of the study of cosmic rays has been acknowledged in many fields, including space weather science and astrobiology. Here, we concentrate on the astrobiological aspects of cosmic rays with regard to the enormous amount of new data available, some of which may, in fact, improve our knowledge about the radiation of cosmic origin on Earth. We focus on fluxes arriving at Earth and doses received, and will guide the reader through the wealth of scientific literature on cosmic rays. We have prepared a concise and self-contained source of data and recipes useful for performing interdisciplinary research in cosmic rays and their effects on life on Earth.

  14. Aerial Neutron Detection of Cosmic-Ray Interactions with the Earth's Surface

    SciTech Connect

    Richard Maurer

    2008-09-18

    We have demonstrated the ability to measure the neutron flux produced by the cosmic-ray interaction with nuclei in the ground surface using aerial neutron detection. High energy cosmic-rays (primarily muons with GeV energies) interact with the nuclei in the ground surface and produce energetic neutrons via spallation. At the air-surface interface, the neutrons produced by spallation will either scatter within the surface material, become thermalized and reabsorbed, or be emitted into the air. The mean free path of energetic neutrons in air can be hundreds of feet as opposed to a few feet in dense materials. As such, the fluxmore » of neutrons escaping into the air provides a measure of the surface nuclei composition. It has been demonstrated that this effect can be measured at long range using neutron detectors on low flying helicopters. Radiological survey measurements conducted at Government Wash in Las Vegas, Nevada, have shown that the neutron background from the cosmic-soil interactions is repeatable and directly correlated to the geological data. Government Wash has a very unique geology, spanning a wide variety of nuclide mixtures and formations. The results of the preliminary measurements are presented.« less

  15. Effect of near-earth thunderstorms electric field on the intensity of ground cosmic ray positrons/electrons in Tibet

    NASA Astrophysics Data System (ADS)

    Zhou, X. X.; Wang, X. J.; Huang, D. H.; Jia, H. Y.

    2016-11-01

    Monte Carlo simulations are performed to study the correlation between the ground cosmic ray intensity and near-earth thunderstorms electric field at YBJ (located at YangBaJing, Tibet, China, 4300 m a. s. l.). The variations of the secondary cosmic ray intensity are found to be highly dependent on the strength and polarity of the electric field. In negative fields and in positive fields greater than 600 V/cm, the total number of ground comic ray positrons and electrons increases with increasing electric field strength. And these values increase more obviously when involving a shower with lower primary energy or a higher zenith angle. While in positive fields ranging from 0 to 600 V/cm, the total number of ground comic ray positrons and electrons declines and the amplitude is up to 3.1% for vertical showers. A decrease of intensity occurs in inclined showers within the range of 0-500 V/cm, which is accompanied by smaller amplitudes. In this paper, the intensity changes are analyzed, especially concerning those decreasing phenomena in positive electric fields. Our simulation results could be helpful in understanding the decreases observed in some ground-based experiments (such as the Carpet air shower array and ARGO-YBJ), and also be useful in understanding the acceleration mechanisms of secondary charged particles caused by an atmospheric electric field.

  16. The DNA of Bacteria of the World Ocean and the Earth in Cosmic Dust at the International Space Station

    PubMed Central

    Grebennikova, T. V.; Syroeshkin, A. V.; Shubralova, E. V.; Eliseeva, O. V.; Kostina, L. V.; Kulikova, N. Y.; Latyshev, O. E.; Morozova, M. A.; Yuzhakov, A. G.; Chichaeva, M. A.; Tsygankov, O. S.

    2018-01-01

    Cosmic dust samples from the surface of the illuminator of the International Space Station (ISS) were collected by a crew member during his spacewalk. The sampler with tampon in a vacuum container was delivered to the Earth. Washouts from the tampon's material and the tampon itself were analyzed for the presence of bacterial DNA by the method of nested PCR with primers specific to DNA of the genus Mycobacteria, DNA of the strains of capsular bacteria Bacillus, and DNA encoding 16S ribosomal RNA. The results of amplification followed by sequencing and phylogenetic analysis indicated the presence of the bacteria of the genus Mycobacteria and the extreme bacterium of the genus Delftia in the samples of cosmic dust. It was shown that the DNA sequence of one of the bacteria of the genus Mycobacteria was genetically similar to that previously observed in superficial micro layer at the Barents and Kara seas' coastal zones. The presence of the wild land and marine bacteria DNA on the ISS suggests their possible transfer from the stratosphere into the ionosphere with the ascending branch of the global electric circuit. Alternatively, the wild land and marine bacteria as well as the ISS bacteria may all have an ultimate space origin. PMID:29849510

  17. The DNA of Bacteria of the World Ocean and the Earth in Cosmic Dust at the International Space Station.

    PubMed

    Grebennikova, T V; Syroeshkin, A V; Shubralova, E V; Eliseeva, O V; Kostina, L V; Kulikova, N Y; Latyshev, O E; Morozova, M A; Yuzhakov, A G; Zlatskiy, I A; Chichaeva, M A; Tsygankov, O S

    2018-01-01

    Cosmic dust samples from the surface of the illuminator of the International Space Station (ISS) were collected by a crew member during his spacewalk. The sampler with tampon in a vacuum container was delivered to the Earth. Washouts from the tampon's material and the tampon itself were analyzed for the presence of bacterial DNA by the method of nested PCR with primers specific to DNA of the genus Mycobacteria , DNA of the strains of capsular bacteria Bacillus , and DNA encoding 16S ribosomal RNA. The results of amplification followed by sequencing and phylogenetic analysis indicated the presence of the bacteria of the genus Mycobacteria and the extreme bacterium of the genus Delftia in the samples of cosmic dust. It was shown that the DNA sequence of one of the bacteria of the genus Mycobacteria was genetically similar to that previously observed in superficial micro layer at the Barents and Kara seas' coastal zones. The presence of the wild land and marine bacteria DNA on the ISS suggests their possible transfer from the stratosphere into the ionosphere with the ascending branch of the global electric circuit. Alternatively, the wild land and marine bacteria as well as the ISS bacteria may all have an ultimate space origin.

  18. Solar cosmic ray hazard to interplanetary and earth-orbital space travel

    NASA Technical Reports Server (NTRS)

    Yucker, W. R.

    1972-01-01

    A statistical treatment of the radiation hazards to astronauts due to solar cosmic ray protons is reported to determine shielding requirements for solar proton events. More recent data are incorporated into the present analysis in order to improve the accuracy of the predicted mission fluence and dose. The effects of the finite data sample are discussed. Mission fluence and dose versus shield thickness data are presented for mission lengths up to 3 years during periods of maximum and minimum solar activity; these correspond to various levels of confidence that the predicted hazard will not be exceeded.

  19. History of cosmic ray influence on ozone layer-key steps

    NASA Astrophysics Data System (ADS)

    Krivolutsky, A.

    The history of cosmic radiation influence as a source of odd nitrogen in the stratosphere began about three decades ago (Dalgarno, 1971; Warneck, 1972). Corresponding estimated NO x production by galactic cosmic rays which leads to one molecular of NO per one pair of ions (Nicolet, 1975) in the stratosphere and mesosphere. First simple model was suggested by Ruderman and Chamberlain (1975) to explain the origin of the sun spot modulation of ozone. Nitric oxide generation in the stratosphere by solar proton events leads to ozone depletion (Crutzen et al., 1975). First results supported this idea were obtained from the board of Nimbus-4 (Heath et al., 1977). Several mechanisms concerning the possibility of cosmic ray influence on climate and life were suggested in different papers (Ruderman, 1974; Reid et al., 1976; Chamberlain, 1977; and others). Many important steps to understand the role of solar protons in atmospheric chemistry have been made by Charles Jackman with co-authors (1978, 1980 up to 2001) Different groups found the response of ozone after SPE in July 2000 using UARS data. It is important now to prolong numerical modeling and observations using new missions like ENVISAT and SAGE-III instrument.

  20. Influence of slip-surface geometry on earth-flow deformation, Montaguto earth flow, southern Italy

    USGS Publications Warehouse

    Guerriero, L.; Coe, Jeffrey A.; Revellio, P.; Grelle, G.; Pinto, F.; Guadagno, F.

    2016-01-01

    We investigated relations between slip-surface geometry and deformational structures and hydrologic features at the Montaguto earth flow in southern Italy between 1954 and 2010. We used 25 boreholes, 15 static cone-penetration tests, and 22 shallow-seismic profiles to define the geometry of basal- and lateral-slip surfaces; and 9 multitemporal maps to quantify the spatial and temporal distribution of normal faults, thrust faults, back-tilted surfaces, strike-slip faults, flank ridges, folds, ponds, and springs. We infer that the slip surface is a repeating series of steeply sloping surfaces (risers) and gently sloping surfaces (treads). Stretching of earth-flow material created normal faults at risers, and shortening of earth-flow material created thrust faults, back-tilted surfaces, and ponds at treads. Individual pairs of risers and treads formed quasi-discrete kinematic zones within the earth flow that operated in unison to transmit pulses of sediment along the length of the flow. The locations of strike-slip faults, flank ridges, and folds were not controlled by basal-slip surface topography but were instead dependent on earth-flow volume and lateral changes in the direction of the earth-flow travel path. The earth-flow travel path was strongly influenced by inactive earth-flow deposits and pre-earth-flow drainages whose positions were determined by tectonic structures. The implications of our results that may be applicable to other earth flows are that structures with strikes normal to the direction of earth-flow motion (e.g., normal faults and thrust faults) can be used as a guide to the geometry of basal-slip surfaces, but that depths to the slip surface (i.e., the thickness of an earth flow) will vary as sediment pulses are transmitted through a flow.

  1. On quasi-periodic variations of low-energy cosmic rays observed near earth.

    PubMed

    Kudela, Karel; Langer, Ronald

    2015-06-01

    Cosmic ray (CR) may partially, especially at high altitudes, contribute to the dosimetric characteristics. Along with irregular CR variations as Forbush decreases and solar particle events are, the quasi-periodic variations may be of some relevance too. A very short review (with references to original papers) of the present knowledge of various types of such variations is presented, namely (i) diurnal wave, (ii) ~27 d variability due to the solar rotation, (iii) Rieger-type periodicity, and (iv) quasi-biennial oscillations as well as waves on longer time scales related to solar activity and to polarity of magnetic field of the Sun. Variability is illustrated in measurements of secondary CR on the ground including the high-altitude observations at Lomnický štít. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. The Big Bang left a permanent scare in the cosmic background, 5 billion light-years from Earth

    NASA Image and Video Library

    2017-12-08

    The events surrounding the Big Bang were so cataclysmic that they left an indelible imprint on the fabric of the cosmos. We can detect these scars today by observing the oldest light in the universe. As it was created nearly 14 billion years ago, this light — which exists now as weak microwave radiation and is thus named the cosmic microwave background (CMB) — permeates the entire cosmos, filling it with detectable photons. The CMB can be used to probe the cosmos via something known as the Sunyaev-Zel’dovich (SZ) effect, which was first observed over 30 years ago. We detect the CMB here on Earth when its constituent microwave photons travel to us through space. On their journey to us, they can pass through galaxy clusters that contain high-energy electrons. These electrons give the photons a tiny boost of energy. Detecting these boosted photons through our telescopes is challenging but important — they can help astronomers to understand some of the fundamental properties of the universe, such as the location and distribution of dense galaxy clusters. The NASA/ESA (European Space Agency) Hubble Space Telescope observed one of most massive known galaxy clusters, RX J1347.5–1145, seen in this Picture of the Week, as part of the Cluster Lensing And Supernova survey with Hubble (CLASH). This observation of the cluster, 5 billion light-years from Earth, helped the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to study the cosmic microwave background using the thermal Sunyaev-Zel’dovich effect. The observations made with ALMA are visible as the blue-purple hues. Image credit: ESA/Hubble & NASA, T. Kitayama (Toho University, Japan)/ESA/Hubble & NASA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to

  3. 2015 Summer Series - Dr. Jose Funes - A Cosmic End: From the Earth to the Universe

    NASA Image and Video Library

    2015-06-23

    Throughout history, humans have used religion and science to explain the world, the universe and the origin of life. Our future lies in our ability to understand Earth and the universe beyond. At times, these may have been seen as two different camps, polarizing the methodology by which we study where we came from and where we are going. Will all life end with Earth, or is life a common phenomenon in the universe? Father Doctor Jose Funes provides an insight on cosmology from the Vatican.

  4. Airborne Detection of Cosmic-Ray Albedo Neutrons for Regional-Scale Surveys of Root-Zone Soil Water on Earth

    NASA Astrophysics Data System (ADS)

    Schrön, M.; Bannehr, L.; Köhli, M.; Zreda, M. G.; Weimar, J.; Zacharias, S.; Oswald, S. E.; Bumberger, J.; Samaniego, L. E.; Schmidt, U.; Zieger, P.; Dietrich, P.

    2017-12-01

    While the detection of albedo neutrons from cosmic rays became a standard method in planetary space science, airborne neutron sensing has never been conceived for hydrological research on Earth. We assessed the applicability of atmospheric neutrons to sense root-zone soil moisture averaged over tens of hectares using neutron detectors on an airborne vehicle. Large-scale quantification of near-surface water content is an urgent challenge in hydrology. Information about soil and plant water is crucial to accurately assess the risks for floods and droughts, to adjust regional weather forecasts, and to calibrate and validate the corresponding models. However, there is a lack of data at scales relevant for these applications. Most conventional ground-based geophysical instruments provide root-zone soil moisture only within a few tens of m2, while electromagnetic signals from conventional remote-sensing instruments can only penetrate the first few centimeters below surface, though at larger spatial areas.In the last couple of years, stationary and roving neutron detectors have been used to sense the albedo component of cosmic-ray neutrons, which represents the average water content within 10—15 hectares and 10—50 cm depth. However, the application of these instruments is limited by inaccessible terrain and interfering local effects from roads. To overcome these limitations, we have pioneered first simulations and experiments of such sensors in the field of airborne geophysics. Theoretical investigations have shown that the footprint increases substantially with height above ground, while local effects smooth out throughout the whole area. Campaigns with neutron detectors mounted on a lightweight gyrocopter have been conducted over areas of various landuse types including agricultural fields, urban areas, forests, flood plains, and lakes. The neutron signal showed influence of soil moisture patterns in heights of up to 180 m above ground. We found correlation with

  5. Inferred cosmic-ray spectrum from Fermi large area telescope γ-ray observations of Earth's limb.

    PubMed

    Ackermann, M; Ajello, M; Albert, A; Allafort, A; Baldini, L; Barbiellini, G; Bastieri, D; Bechtol, K; Bellazzini, R; Blandford, R D; Bloom, E D; Bonamente, E; Bottacini, E; Bouvier, A; Brandt, T J; Brigida, M; Bruel, P; Buehler, R; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Cecchi, C; Charles, E; Chaves, R C G; Chekhtman, A; Chiang, J; Chiaro, G; Ciprini, S; Claus, R; Cohen-Tanugi, J; Conrad, J; Cutini, S; Dalton, M; D'Ammando, F; de Angelis, A; de Palma, F; Dermer, C D; Digel, S W; Di Venere, L; do Couto e Silva, E; Drell, P S; Drlica-Wagner, A; Favuzzi, C; Fegan, S J; Ferrara, E C; Focke, W B; Franckowiak, A; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Germani, S; Giglietto, N; Giordano, F; Giroletti, M; Glanzman, T; Godfrey, G; Gomez-Vargas, G A; Grenier, I A; Grove, J E; Guiriec, S; Gustafsson, M; Hadasch, D; Hanabata, Y; Harding, A K; Hayashida, M; Hayashi, K; Hewitt, J W; Horan, D; Hou, X; Hughes, R E; Inoue, Y; Jackson, M S; Jogler, T; Jóhannesson, G; Johnson, A S; Kamae, T; Kawano, T; Knödlseder, J; Kuss, M; Lande, J; Larsson, S; Latronico, L; Longo, F; Loparco, F; Lovellette, M N; Lubrano, P; Mayer, M; Mazziotta, M N; McEnery, J E; Mehault, J; Michelson, P F; Mitthumsiri, W; Mizuno, T; Moiseev, A A; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nemmen, R; Nuss, E; Ohsugi, T; Okumura, A; Orienti, M; Orlando, E; Ormes, J F; Paneque, D; Panetta, J H; Perkins, J S; Pesce-Rollins, M; Piron, F; Pivato, G; Porter, T A; Rainò, S; Rando, R; Razzano, M; Razzaque, S; Reimer, A; Reimer, O; Ritz, S; Roth, M; Schaal, M; Schulz, A; Sgrò, C; Siskind, E J; Spandre, G; Spinelli, P; Strong, A W; Takahashi, H; Takeuchi, Y; Thayer, J G; Thayer, J B; Thompson, D J; Tibaldo, L; Tinivella, M; Torres, D F; Tosti, G; Troja, E; Tronconi, V; Usher, T L; Vandenbroucke, J; Vasileiou, V; Vianello, G; Vitale, V; Werner, M; Winer, B L; Wood, K S; Wood, M; Yang, Z

    2014-04-18

    Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the γ-ray emission from Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range ∼90  GeV-6  TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68±0.04 and 2.61±0.08 above ∼200  GeV, respectively.

  6. Inferred Cosmic-Ray Spectrum from Fermi-LAT Gamma-Ray Observations of the Earths Limb

    NASA Technical Reports Server (NTRS)

    Ackermann, M.; Ajello, M.; Albert, A.; Allafort, A.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Blandford, R. D.; hide

    2014-01-01

    Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly-discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the -ray emission from the Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range approx. 90 GeV-6 TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68 +/- 0.04 and 2.61 +/- 0.08 above approx. 200 GeV, respectively.

  7. Galactic-cosmic-ray-produced 3He in a ferromanganese crust: any supernova 60Fe excess on earth?

    PubMed

    Basu, S; Stuart, F M; Schnabel, C; Klemm, V

    2007-04-06

    An excess of 60Fe in 2.4-3.2 x 10(6) year old ferromanganese crust (237 KD) from the deep Pacific Ocean has been considered as evidence for the delivery of debris from a nearby supernova explosion to Earth. Extremely high ;{3}He/;{4}He (up to 6.12 x 10(-3)) and 3He concentrations (up to 8 x 10(9) atoms/g) measured in 237 KD cannot be supernova-derived. The helium is produced by galactic cosmic rays (GCR) and delivered in micrometeorites that have survived atmospheric entry to be trapped by the crust. 60Fe is produced by GCR reactions on Ni in extraterrestrial material. The maximum (3)He/(60)Fe of 237 KD (80-850) is comparable to the GCR (3)He/(60)Fe production ratio (400-500) predicted for Ni-bearing minerals in iron meteorites. The excess 60Fe can be plausibly explained by the presence of micrometeorites trapped by the crust, rather than injection from a supernova source.

  8. Cosmic Carbon Chemistry: From the Interstellar Medium to the Early Earth

    PubMed Central

    Ehrenfreund, Pascale; Cami, Jan

    2010-01-01

    Astronomical observations have shown that carbonaceous compounds in the gas and solid state, refractory and icy are ubiquitous in our and distant galaxies. Interstellar molecular clouds and circumstellar envelopes are factories of complex molecular synthesis. A surprisingly large number of molecules that are used in contemporary biochemistry on Earth are found in the interstellar medium, planetary atmospheres and surfaces, comets, asteroids and meteorites, and interplanetary dust particles. In this article we review the current knowledge of abundant organic material in different space environments and investigate the connection between presolar and solar system material, based on observations of interstellar dust and gas, cometary volatiles, simulation experiments, and the analysis of extraterrestrial matter. Current challenges in astrochemistry are discussed and future research directions are proposed. PMID:20554702

  9. Investigating the Present Day Cosmic Dust Flux at the Earth's Surface: Initial Results from the Kwajalein Micrometeorite Collection

    NASA Technical Reports Server (NTRS)

    Wozniakiewicz, P. J.; Bradley, J. P.; Price, M. C.; Zolensky, M. E.; Ishii, H. A.; Brownlee, D. E.; Russell, S. S.

    2014-01-01

    Examination of impact craters on the Long Duration Exposure Facility satellite indicate a present day micrometeoroid flux of approx. 30,000 tonnes [1 after 2]. But what portion of this material arrives at the Earth's surface as micrometeorites? Studies of available micrometeorite collections from deep sea sediments [e.g. 3], Greenland blue ice [e.g. 4] and the South Pole water well [e.g. 1] may be complicated by terrestrial weathering and, in some cases, collection bias (magnetic separation for deep sea sediments) and poorly constrained ages. We have recently set up a micrometeorite collection station on Kwajalein Island in the Republic of the Marshall Islands in the Pacific Ocean, using high volume air samplers to collect particles directly from the atmosphere. By collecting in this way, the terrestrial age of the particles is known, the weathering they experience is minimal, and we are able to constrain particle arrival times. Collecting at this location also exploits the considerably reduced anthropogenic background [5]. Method: High volume air samplers were installed on top of the two-story airport building on Kwajalein. These were fitted with polycarbonate membrane filters with 5µm diameter perforations. The flow rates were set to 0.5m3/min, and filters were changed once a week. After collection, filters were washed to remove salt and concentrate particles [see 5] in preparation for analysis by SEM. Results and Discussion: A selection of filters have been prepared and surveyed. Due to their ease of identification our initial investigations have focused on particles resembling cosmic spherules. The spheres can be divided into three main groups: 1. Silicate spherules rich in Al, Ca, K and Na (to varying degrees), 2. Silicate spherules rich in Mg and Fe and 3. Fe-rich spherules. Group 1 spherules are often vesiculated and can occur as aggregates. They are similar in appearance and composition to volcanic microspheres [e.g. 6] and are thus likely terrestrial in

  10. A Shifting Shield Provides Protection Against Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-12-01

    at Earth.In a new study, a team of scientists led by Nicola Tomassetti (University of Perugia, Italy) has modeled this solar modulation to better understand the process by which the Suns changing activity influences the cosmic ray flux that reaches us at Earth.Modeling a LagTomassetti and collaborators model uses two solar-activity observables as inputs: the number of sunspots and the tilt angle of the heliospheric current sheet. By modeling basic transport processes in the heliosphere, the authors then track the impact that the changing solar properties have on incoming galactic cosmic rays. In particular, the team explores the time lag between when solar activity changes and when we see the responding change in the cosmic-ray flux.Cosmic-ray flux observations are best fit by the authors model when an 8-month lag is included (red bold line). A comparison model with no lag (black dashed line) is included. [Tomassetti et al. 2017]By comparing their model outputs to the large collection of time-dependent observations of cosmic-ray fluxes, Tomassetti and collaborators show that the best fit to data occurs with an 8-month lag between changing solar activity and local cosmic-ray flux modulation.This is an important outcome for studying the processes that affect the cosmic-ray flux that reaches Earth. But theres an additional intriguing consequence of this result: knowledge of the current solar activity could allow us to predict the modulation that will occur for cosmic rays near Earth an entire 8 months from now! If this model is correct, it brings us one step closer to being able to plan safer space missions for the future.CitationNicola Tomassetti et al 2017 ApJL 849 L32. doi:10.3847/2041-8213/aa9373

  11. Inconstant sun: how solar evolution has affected cosmic and ultraviolet radiation exposure over the history of life on Earth.

    PubMed

    Karam, P Andrew

    2003-03-01

    Four billion years ago, sea-level UV exposure was more than 400 times as intense as today, the dose from solar cosmic rays was five times present levels, and galactic cosmic rays accounted for only about 10% their current contribution to sea-level radiation doses. Exposure to cosmic radiation accounts for about 10% of natural background radiation exposure today and includes dose from galactic cosmic rays and solar charged particles. There is little exposure to ionizing wavelengths of UV due to absorption by ozone. The sun has evolved significantly over its life; in the past there were higher levels of particulate radiation and lower UV emissions from the sun, and a stronger solar wind reduced radiation dose in the inner solar system from galactic cosmic rays. Finally, since the early atmosphere contained little to no oxygen, surface levels of UV radiation were far higher in the past.

  12. The influence of the observatory latitude on the study of ultra high energy cosmic rays

    SciTech Connect

    Anjos, Rita C. dos; De Souza, Vitor; De Almeida, Rogerio M.

    2017-07-01

    Recent precision measurements of the Ultra High Energy Cosmic Rays (UHECR) arrival directions, spectrum and parameters related to the mass of the primary particle have been done by the HiRes, Pierre Auger and Telescope Array (TA) Observatories. In this paper, distributions of arrival directions of events in the nearby Universe are assumed to correlate with sources in the 2MASS Redshift Survey (2MRS), IRAS 1.2 Jy Survey, Palermo Swift-BAT and Swift-BAT catalogs, and the effect of the latitude of the observatory on the measurement of the energy spectrum and on the capability of measuring anisotropy is studied. The differences between givenmore » latitudes on the northern and southern hemispheres are quantified. It is shown that the latitude of the observatory: a) has an influence on the total flux measured and b) imposes an important limitation on the capability of measuring an anisotropic sky.« less

  13. Isotopic Evidence for Multi-stage Cosmic-ray Exposure Histories of Lunar Meteorites: Long Residence on the Moon and Short Transition to the Earth

    NASA Astrophysics Data System (ADS)

    Hidaka, Hiroshi; Sakuma, Keisuke; Nishiizumi, Kunihiko; Yoneda, Shigekazu

    2017-06-01

    It is known that most lunar meteorites have complicated cosmic-ray exposure experiences on the Moon and in space. In this study, cosmic-ray irradiation histories of six lunar meteorites, Dhofar 489, Northwest Africa 032 (NWA 032), NWA 479, NWA 482, NWA 2995, and NWA 5000, were characterized from neutron-captured isotopic shifts of Sm and Gd, and from the abundances of long-lived cosmogenic radionuclides like 10Be, 26Al, 36Cl, and 41Ca. Sm and Gd isotopic data of all of six meteorites show significant isotopic shifts of 149Sm-150Sm and 157Gd-158Gd caused by accumulation of neutron capture reactions due to cosmic-ray irradiation, corresponding to the neutron fluences of (1.3-9.6) × 1016 n cm-2. In particular, very large Sm and Gd isotopic shifts of NWA 482 are over those of a lunar regolith 70002, having the largest isotopic shifts among the Apollo regolith samples, corresponding to cosmic-ray exposure duration over 800 million years in the lunar surface (2π irradiation). Meanwhile, the concentrations of cosmogenic radionuclides for individual six meteorites show the short irradiation time less than one million years as their bodies in space (4π irradiation). Our data also support the results of previous studies, revealing that most of lunar meteorites have long exposure ages at shallow depths on the Moon and short transit times from the Moon to the Earth.

  14. Cosmic Rays in Thunderstorms

    NASA Astrophysics Data System (ADS)

    Buitink, Stijn; Scholten, Olaf; van den Berg, Ad; Ebert, Ute

    2013-04-01

    Cosmic Rays in Thunderstorms Cosmic rays are protons and heavier nuclei that constantly bombard the Earth's atmosphere with energies spanning a vast range from 109 to 1021 eV. At typical altitudes up to 10-20 km they initiate large particle cascades, called extensive air showers, that contain millions to billions of secondary particles depending on their initial energy. These particles include electrons, positrons, hadrons and muons, and are concentrated in a compact particle front that propagates at relativistic speed. In addition, the shower leaves behind a trail of lower energy electrons from ionization of air molecules. Under thunderstorm conditions these electrons contribute to the electrical and ionization processes in the cloud. When the local electric field is strong enough the secondary electrons can create relativistic electron run-away avalanches [1] or even non-relativistic avalanches. Cosmic rays could even trigger lightning inception. Conversely, strong electric fields also influence the development of the air shower [2]. Extensive air showers emit a short (tens of nanoseconds) radio pulse due to deflection of the shower particles in the Earth's magnetic field [3]. Antenna arrays, such as AERA, LOFAR and LOPES detect these pulses in a frequency window of roughly 10-100 MHz. These systems are also sensitive to the radiation from discharges associated to thunderstorms, and provide a means to study the interaction of cosmic ray air showers and the electrical processes in thunderstorms [4]. In this presentation we discuss the involved radiation mechanisms and present analyses of thunderstorm data from air shower arrays [1] A. Gurevich et al., Phys. Lett. A 165, 463 (1992) [2] S. Buitink et al., Astropart. Phys. 33, 1 (2010) [3] H. Falcke et al., Nature 435, 313 (2005) [4] S. Buitink et al., Astron. & Astrophys. 467, 385 (2007)

  15. Influence of cosmic radiation and/or microgravity on development of Carausius morosus.

    PubMed

    Reitz, G; Bucker, H; Facius, R; Horneck, G; Graul, E H; Berger, H; Ruther, W; Heinrich, W; Beaujean, R; Enge, W; Alpatov, A M; Ushakov, I A; Zachvatkin YuA; Mesland, D A

    1989-01-01

    Eggs of Carausius morosus were exposed to spaceflight conditions in two spaceflight missions, the German 7 day Spacelab Mission D1 and the Soviet 12.56 day Biosatellite Mission "COSMOS 1887". During spaceflight the eggs continued their development. Eggs of five different ages representing different sensitivity to radiation and different capacity to regeneration were used to investigate the influence of cosmic radiation and/or microgravity on insect development. Using the Biostack concept--eggs in monolayers sandwiched between nuclear track detectors--and the 1 g reference centrifuge of BIORACK in D1 we were able to separate effects of heavy ions of the cosmic radiation from microgravity effects and also from combined effects of these two factors in space. After retrieval, hatching rates, embryonic and larval growth kinetics and anomaly frequencies were determined. Microgravity leads to a reduced hatching rate of eggs exposed in the early stages of development. Hatching was normal in eggs which were exposed on the 1 g reference centrifuge. Hits by heavy ions caused body anomalies. The combined action of heavy ions and microgravity resulted in an unexpectedly high frequency of anomalies. These results obtained from the Spacelab Mission D1, were confirmed in an experiment onboard of COSMOS 1887. In addition to the previous analysis, embryonic development before hatching was followed which showed no major difference between flight and the ground control specimens. Since a reconfirmation of reduced hatching rates was observed in COSMOS 1887, too, the above results suggest some microgravity induced functional impairment of the hatching activity, rather than blockage in embryonic development.

  16. Laser fiber-optic sensors for investigation of influences ultra weak cosmic radiation on the people.

    NASA Astrophysics Data System (ADS)

    Rzhavin, Yu.; Ignatiev, A.

    The present work describes investigation of influences ultra weak cosmic radiation on the people, using laser fiber-optic bio sensors. Potential of the people measurements is made on the basis of two Mach-Zender interferometers. The measuring and reference channels of the device are made in the form of signal-mode light guides with w-profile, which retain the polarization of light [1].The effect of measurements leads to axial compression of the w-fiber guides in the measuring channel. The measured signal is recorded by the relative displasement of the structure of the interference pattern, which is caused by phase modulation of a coherent light wave [2] propagating in the measuring channel. The light guides in the measuring channel reeled up on a flat surface on a cirle by a diameter 1.8 meter. Length light guides made 100 meters. The people approached on distance of 0.3 meters to flat surfased. It has been demonstrated that the method based on calculation of the mutual correlation function of the output signals of the interferometers makes it possible to raise the signal/noise ratio of the device by eliminating irregular noise waves and reproducing an accurate shape of the measured signal.As the light source, we have used single-frequency semiconductor injection laser which external resonator was used and one of a resonator mirrors was the w-lightguide end with reflection structure deposited on it .The w-lightguidess had the cup-off wave length 1,1 um, the degree of retention of polarization 99 %. It has been demonstrated experimentally that the of the developed sensor, under constant level of the cosmic radiation measured bio potential of the people was defined from age, weight, and psychological of the condition. REFERENCES 1.Yu.I .Rzhavin et.al. Proceeding SPIE , vol. 2349 , pp.154-157 2. Yu.I.Rzhavin Proceeding SPIE , vol. 4827 , pp.253-257

  17. Influence of fortnightly earth tides at Kilauea Volcano, Hawaii.

    USGS Publications Warehouse

    Dzurisin, D.

    1980-01-01

    Analysis of 52 historic eruptions confirms the premise that fortnightly earth tides play a significant role in triggering activity at Kilauea Volcano, Hawaii. Since January 1832, nearly twice as many eruptions have occurred nearer fortnightly tidal maximum than tidal minimum (34 vs. 18). A straightforward significance test indicates that the likelihood of a fortnightly tidal influence on Kilauea eruptions is roughly 90%. This is not the case for Mauna Loa Volcano, where 37 historic eruptions have been distributed randomly with respect to the fortnightly tide. At Kilauea, stresses induced by fortnightly earth tides presumably act in concert with volcanic and tectonic stresses to trigger shallow magma movements along preexisting zones of weakness. Differences in structure or internal plumbing may limit the effectiveness of this mechanism at Mauna Loa. Tidal effects seem to be less marked at shields than at some island-arc volcanoes, possibly because higher average volcanic stress rates in Hawaii more often override the effects of tidal stresses.-Author

  18. Influence of gravity on deformation of blocks in Earth's crust

    NASA Astrophysics Data System (ADS)

    Tataurova, A. A.; Stefanov, Yu. P.; Bakeev, R. A.

    2017-12-01

    The article presents the results of numerical calculations of deformation using an Earth's crust model fragment under the influence of gravitational force. It is shown that plastic deformation in low-strength blocks changes the stress-strain state in the medium and produces a surface deflection which is hundred meters deep. The deflection is defined by the properties of the medium, its extent, and conditions at the lateral boundaries. The order of load application beyond the elastic limit affects the development of deformation, which should be taken into account when formulating problems and performing numerical simulations. The problem has been solved using a two-dimensional elastoplastic approach.

  19. Influence of land-surface evapotranspiration on the earth's climate

    NASA Technical Reports Server (NTRS)

    Shukla, J.; Mintz, Y.

    1982-01-01

    Land-surface evapotranspiration is shown to strongly influence global fields of rainfall, temperature and motion by calculations using a numerical model of the atmosphere, confirming the general belief in the importance of evapotranspiration-producing surface vegetation for the earth's climate. The current version of the Goddard Laboratory atmospheric general circulation model is used in the present experiment, in which conservation equations for mass, momentum, moisture and energy are expressed in finite-difference form for a spherical grid to calculate (1) surface pressure field evolution, and (2) the wind, temperature, and water vapor fields at nine levels between the surface and a 20 km height.

  20. Space Weather Influence on the Earth wheat markets: past, present, and future.

    NASA Astrophysics Data System (ADS)

    Pustil'Nik, Lev

    solar wind, high cosmic ray flux and North Atlantic cloudiness, caused by CR excess, with negative sequences for wheat agriculture in this humid zone. In the same time wheat markets in the South Europe (Spain, Italy) show reliable sensitivity to space weather state in the opposite (maximum) phase of solar activity with strong solar wind, low cosmic ray flux and deficit of CR input in cloudiness in North Atlantic with next deficit of precipitations in the arid zones of the South Europe. In the same time the large part of markets in the Central Europe zone, functioned far from "high risk agriculture state" show the absence of any effects-responses on space weather. This asymmetry is in accordance with model expectation in the frame of proposed approach. For extremely case of the Iceland agriculture we show that drop of agriculture production in unfavorable states of space weather leads to mass mortality from famines correlated with phase of solar activity with high confi- dence level. We discuss possible increasing of sensitivity of wheat markets to space weather effects in condition of drastic and fast change of modern climate, caused by global warming of the Earth atmosphere with fast and unexpected shift of numerous agriculture regions in the world to state of "high risk agriculture zone". Publications on the theme of review: I. "INFLUENCE OF SOLAR ACTIVITY ON THE STATE OF THE WHEAT MARKET IN MEDIEVAL ENGLAND", Solar Physics 223: 335-356, 2004. c 2004 Kluwer Academic Publishers II. "SPACE CLIMATE MANIFESTATION IN EARTH PRICES - FROM MEDIEVAL ENGLAND UP TO MODERN U.S.A.", LEV PUSTIL'NIK and GREGORY YOM DIN, Solar Physics, 224: 473-481 c Springer 2005

  1. Influence of the backreaction of streaming cosmic rays on magnetic field generation and thermal instability

    SciTech Connect

    Nekrasov, Anatoly K.; Shadmehri, Mohsen, E-mail: anekrasov@ifz.ru, E-mail: nekrasov.anatoly@gmail.com, E-mail: m.shadmehri@gu.ac.ir

    2014-06-10

    Using a multifluid approach, we investigate streaming and thermal instabilities of the electron-ion plasma with homogeneous cold cosmic rays propagating perpendicular to the background magnetic field. Perturbations are also considered to be across the magnetic field. The backreaction of cosmic rays resulting in strong streaming instabilities is taken into account. It is shown that, for sufficiently short wavelength perturbations, the growth rates can exceed the growth rate of cosmic-ray streaming instability along the magnetic field, found by Nekrasov and Shadmehri, which is in turn considerably larger than the growth rate of the Bell instability. The thermal instability is shown notmore » to be subject to the action of cosmic rays in the model under consideration. The dispersion relation for the thermal instability has been derived, which includes sound velocities of plasma and cosmic rays and Alfvén and cosmic-ray streaming velocities. The relation between these parameters determines the kind of thermal instability ranging from the Parker to the Field instabilities. The results obtained can be useful for a more detailed investigation of electron-ion astrophysical objects, such as supernova remnant shocks, galaxy clusters, and others, including the dynamics of streaming cosmic rays.« less

  2. A possible mechanism for the capture of microparticles by the earth and other planets of the solar system. [planetary gravitation effects on cosmic dust particles

    NASA Technical Reports Server (NTRS)

    Dibenedetto, F.

    1973-01-01

    By application of Lyttleton's theory for the formation of comets, it is shown that a possible mechanism for the origin and formation of a concentration of cosmic particles around the earth and the other planets of the solar system exists. In the vicinity of the neutral point, where the velocity of colliding particles is not greater than 6 km/s, it is found that if the solid particles after collision must remain in a solid state, there can be no possibility of accretion for Mercury, Mars, and the Moon, where the maximum value of the distance of the center of the planet to the asymptotic trajectory is less than the radius of the planet. On the other hand, the capture radii of microparticles in solid form varies from a minimum of 2.95 planetary radii for Venus and 3.47 for the Earth, to about 986 for Jupiter.

  3. Isotopic Evidence for Multi-stage Cosmic-ray Exposure Histories of Lunar Meteorites: Long Residence on the Moon and Short Transition to the Earth

    SciTech Connect

    Hidaka, Hiroshi; Sakuma, Keisuke; Nishiizumi, Kunihiko

    It is known that most lunar meteorites have complicated cosmic-ray exposure experiences on the Moon and in space. In this study, cosmic-ray irradiation histories of six lunar meteorites, Dhofar 489, Northwest Africa 032 (NWA 032), NWA 479, NWA 482, NWA 2995, and NWA 5000, were characterized from neutron-captured isotopic shifts of Sm and Gd, and from the abundances of long-lived cosmogenic radionuclides like {sup 10}Be, {sup 26}Al, {sup 36}Cl, and {sup 41}Ca. Sm and Gd isotopic data of all of six meteorites show significant isotopic shifts of {sup 149}Sm–{sup 150}Sm and {sup 157}Gd–{sup 158}Gd caused by accumulation of neutron capturemore » reactions due to cosmic-ray irradiation, corresponding to the neutron fluences of (1.3–9.6) × 10{sup 16} n cm{sup −2}. In particular, very large Sm and Gd isotopic shifts of NWA 482 are over those of a lunar regolith 70002, having the largest isotopic shifts among the Apollo regolith samples, corresponding to cosmic-ray exposure duration over 800 million years in the lunar surface (2 π irradiation). Meanwhile, the concentrations of cosmogenic radionuclides for individual six meteorites show the short irradiation time less than one million years as their bodies in space (4 π irradiation). Our data also support the results of previous studies, revealing that most of lunar meteorites have long exposure ages at shallow depths on the Moon and short transit times from the Moon to the Earth.« less

  4. Biomarker response to galactic cosmic ray-induced NOx and the methane greenhouse effect in the atmosphere of an Earth-like planet orbiting an M dwarf star.

    PubMed

    Grenfell, John Lee; Griessmeier, Jean-Mathias; Patzer, Beate; Rauer, Heike; Segura, Antigona; Stadelmann, Anja; Stracke, Barbara; Titz, Ruth; Von Paris, Philip

    2007-02-01

    Planets orbiting in the habitable zone of M dwarf stars are subject to high levels of galactic cosmic rays (GCRs), which produce nitrogen oxides (NOx) in Earth-like atmospheres. We investigate to what extent these NO(Mx) species may modify biomarker compounds such as ozone (O3) and nitrous oxide (N2O), as well as related compounds such as water (H2O) (essential for life) and methane (CH4) (which has both abiotic and biotic sources). Our model results suggest that such signals are robust, changing in the M star world atmospheric column due to GCR NOx effects by up to 20% compared to an M star run without GCR effects, and can therefore survive at least the effects of GCRs. We have not, however, investigated stellar cosmic rays here. CH4 levels are about 10 times higher on M star worlds than on Earth because of a lowering in hydroxyl (OH) in response to changes in the ultraviolet. The higher levels of CH4 are less than reported in previous studies. This difference arose partly because we used different biogenic input. For example, we employed 23% lower CH4 fluxes compared to those studies. Unlike on Earth, relatively modest changes in these fluxes can lead to larger changes in the concentrations of biomarker and related species on the M star world. We calculate a CH4 greenhouse heating effect of up to 4K. O3 photochemistry in terms of the smog mechanism and the catalytic loss cycles on the M star world differs considerably compared with that of Earth.

  5. The origin of cosmic rays

    NASA Technical Reports Server (NTRS)

    Eichler, D.

    1986-01-01

    Data related to the development of cosmic rays are discussed. The relationship between cosmic ray production and the steady-state Boltzmann equation is analyzed. The importance of the power-law spectrum, the scattering rate, the theory of shock acceleration, anisotropic instabilities, and cosmic ray diffusion in the formation of cosmic rays is described. It is noted that spacecraft observations at the earth's bow shock are useful for studying cosmic rays and that the data support the collisionless shock-wave theory of cosmic ray origin.

  6. The extreme solar cosmic ray particle event on 20 January 2005 and its influence on the radiation dose rate at aircraft altitude.

    PubMed

    Bütikofer, R; Flückiger, E O; Desorgher, L; Moser, M R

    2008-03-01

    In January 2005 toward the end of solar activity cycle 23 the Sun was very active. Between 15 and 20 January 2005, the solar active region NOAA AR 10720 produced five powerful solar flares. In association with this major solar activity several pronounced variations in the ground-level cosmic ray intensity were observed. The fifth of these flares (X7.1) produced energetic solar cosmic rays that caused a giant increase in the count rates of the ground-based cosmic ray detectors (neutron monitors). At southern polar neutron monitor stations the increase of the count rate reached several thousand percent. From the recordings of the worldwide network of neutron monitors, we determined the characteristics of the solar particle flux near Earth. In the initial phase of the event, the solar cosmic ray flux near Earth was extremely anisotropic. The energy spectrum of the solar cosmic rays was fairly soft during the main and the decay phase. We investigated also the flux of different secondary particle species in the atmosphere and the radiation dosage at flight altitude. Our analysis shows a maximum increment of the effective dose rate due to solar cosmic rays in the south polar region around 70 degrees S and 130 degrees E at flight altitude of almost three orders of magnitude.

  7. Response of Atmospheric Biomarkers to NOx-Induced Photochemistry Generated by Stellar Cosmic Rays for Earth-like Planets in the Habitable Zone of M Dwarf Stars

    PubMed Central

    Grießmeier, Jean-Mathias; von Paris, Philip; Patzer, A. Beate C.; Lammer, Helmut; Stracke, Barbara; Gebauer, Stefanie; Schreier, Franz; Rauer, Heike

    2012-01-01

    Abstract Understanding whether M dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research. If such planets exist, the question remains as to whether they could be identified via spectral signatures of biomarkers. Such planets may be exposed to extreme intensities of cosmic rays that could perturb their atmospheric photochemistry. Here, we consider stellar activity of M dwarfs ranging from quiet up to strong flaring conditions and investigate one particular effect upon biomarkers, namely, the ability of secondary electrons caused by stellar cosmic rays to break up atmospheric molecular nitrogen (N2), which leads to production of nitrogen oxides (NOx) in the planetary atmosphere, hence affecting biomarkers such as ozone (O3). We apply a stationary model, that is, without a time dependence; hence we are calculating the limiting case where the atmospheric chemistry response time of the biomarkers is assumed to be slow and remains constant compared with rapid forcing by the impinging stellar flares. This point should be further explored in future work with time-dependent models. We estimate the NOx production using an air shower approach and evaluate the implications using a climate-chemical model of the planetary atmosphere. O3 formation proceeds via the reaction O+O2+M→O3+M. At high NOx abundances, the O atoms arise mainly from NO2 photolysis, whereas on Earth this occurs via the photolysis of molecular oxygen (O2). For the flaring case, O3 is mainly destroyed via direct titration, NO+O3→NO2+O2, and not via the familiar catalytic cycle photochemistry, which occurs on Earth. For scenarios with low O3, Rayleigh scattering by the main atmospheric gases (O2, N2, and CO2) became more important for shielding the planetary surface from UV radiation. A major result of this work is that the biomarker O3 survived all the stellar-activity scenarios considered except for the strong case, whereas the biomarker

  8. Influence of fortnightly earth tides at Kilauea Volcano, Hawaii

    SciTech Connect

    Dzurisin, D.

    1980-11-01

    Analysis of 52 historic eruptions confirms the premise that fortnightly earth tides play a significant role in triggering activity at Kilauea Volcano, Hawaii. Since January 1832, nearly twice as many eruptions have occurred nearer fortnightly tidal maximum than tidal minimum (34 vs 18). A straightforward significance test indicates that the likelihood of a fortnightly tidal influence on Kilauea eruptions is roughly 90%. This is not the case for Mauna Loa Volcano, where 37 historic eruptions have been distributed randomly with respect to the fortnightly tide. At Kilauea, stresses induced by fortnightly earth tides presumably act in concert with volcanic andmore » tectonic stresses to trigger shallow magma movements along preexisting zones of weakness. Differences in structure or internal plumbing may limit the effectiveness of this mechanism at Mauna Loa. Tidal effects seem to be less marked at shields than at some island-arc volcanoes, possibly because higher average volcanic stress rates in Hawaii more often override the effects of tidal stresses.« less

  9. Earth Versus Neutrinos: Measuring the Total Muon-Neutrino-to-Nucleon Cross Section at Ultra-High Energies through Differential Earth Absorption of Muon Neutrinos from Cosmic Rays Using the IceCube Detector

    NASA Astrophysics Data System (ADS)

    Miarecki, Sandra Christine

    The IceCube Neutrino Detector at the South Pole was constructed to measure the flux of high-energy neutrinos and to try to identify their cosmic sources. In addition to these astrophysical neutrinos, IceCube also detects the neutrinos that result from cosmic ray interactions with the atmosphere. These atmospheric neutrinos can be used to measure the total muon neutrino-to-nucleon cross section by measuring neutrino absorption in the Earth. The measurement involves isolating a sample of 10,784 Earth-transiting muons detected by IceCube in its 79-string configuration. The cross-section is determined using a two-dimensional fit in measured muon energy and zenith angle and is presented as a multiple of the Standard Model expectation as calculated by Cooper-Sarkar, Mertsch, and Sarkar in 2011. A multiple of 1.0 would indicate agreement with the Standard Model. The results of this analysis find the multiple to be 1.30 (+0.21 -0.19 statistical) (+0.40 -0.44 systematic) for the neutrino energy range of 6.3 to 980 TeV, which is in agreement with the Standard Model expectation.

  10. Separation of the Galactic Cosmic Rays and Inner Earth Radiation Belt Contributions to the Daily Dose Onboard the International Space Station in 2005-2011

    NASA Astrophysics Data System (ADS)

    Lishnevskii, A. E.; Benghin, V. V.

    2018-03-01

    The DB-8 detectors of the ISS radiation monitoring system (RMS) have operated almost continuously onboard the ISS service module since August 2001 till December 2014. The RMS data obtained were used for the daily monitoring of the radiation environment aboard the station. This paper considers the technique of RMS data analysis that allows one to distinguish the contributions of galactic cosmic rays and the Earth's inner radiation belt to the daily dose based on the dosimetry data obtained as a result of the station's passage in areas of the highest geomagnetic latitudes. The paper presents the results of an analysis of the dosimetry data based on this technique for 2005-2011, as well as a comparison with similar results the authors obtained previously using the technique based on an analysis of the dosimetry data obtained during station passages in the area of the South Atlantic Anomaly.

  11. Influence of the Solar Cycle on Turbulence Properties and Cosmic-Ray Diffusion

    NASA Astrophysics Data System (ADS)

    Zhao, L.-L.; Adhikari, L.; Zank, G. P.; Hu, Q.; Feng, X. S.

    2018-04-01

    The solar cycle dependence of various turbulence quantities and cosmic-ray (CR) diffusion coefficients is investigated by using OMNI 1 minute resolution data over 22 years. We employ Elsässer variables z ± to calculate the magnetic field turbulence energy and correlation lengths for both the inwardly and outwardly directed interplanetary magnetic field (IMF). We present the temporal evolution of both large-scale solar wind (SW) plasma variables and small-scale magnetic fluctuations. Based on these observed quantities, we study the influence of solar activity on CR parallel and perpendicular diffusion using quasi-linear theory and nonlinear guiding center theory, respectively. We also evaluate the radial evolution of the CR diffusion coefficients by using the boundary conditions for different solar activity levels. We find that in the ecliptic plane at 1 au (1), the large-scale SW temperature T, velocity V sw, Alfvén speed V A , and IMF magnitude B 0 are positively related to solar activity; (2) the fluctuating magnetic energy density < {{z}+/- }2> , residual energy E D , and corresponding correlation functions all have an obvious solar cycle dependence. The residual energy E D is always negative, which indicates that the energy in magnetic fluctuations is larger than the energy in kinetic fluctuations, especially at solar maximum; (3) the correlation length λ for magnetic fluctuations does not show significant solar cycle variation; (4) the temporally varying shear source of turbulence, which is most important in the inner heliosphere, depends on the solar cycle; (5) small-scale fluctuations may not depend on the direction of the background magnetic field; and (6) high levels of SW fluctuations will increase CR perpendicular diffusion and decrease CR parallel diffusion, but this trend can be masked if the background IMF changes in concert with turbulence in response to solar activity. These results provide quantitative inputs for both turbulence transport

  12. [Observation on twins of cosmic radiation influence as a risk factor].

    PubMed

    Vişănescu, Magdalena

    2009-01-01

    During flight, cosmic radiation is capable to penetrate the walls of airplanes and produce mutations in human chromosomes. To evaluate the correlations between cosmic radiation and the pathology of flying personnel. Two twin patients, one with 15 years work as a flight crew member, and the other with regular work on the ground. The patients were examined clinically, biochemically and with imaging methods. The genetic and environmental contribution to their pathology was noted. The patient, working in flight, received additional genetic tests to refute or to confirm the presence of chromosome alterations induced by the cosmic radiation. The patient, member of the flight crew, presented hypercholesterolemia, more evident structure modifications of the mammary gland, but chromosome alterations were not present. Having a first grade relative with dyslipidemia and uterine cancer, the structural or blood homeostasis modifications of the flight crew member can be either due to a high, genetically transmitted, susceptibility to the effects of the plane's microclimate and possibly to effects of lifestyle.

  13. Response of atmospheric biomarkers to NO(x)-induced photochemistry generated by stellar cosmic rays for earth-like planets in the habitable zone of M dwarf stars.

    PubMed

    Grenfell, John Lee; Grießmeier, Jean-Mathias; von Paris, Philip; Patzer, A Beate C; Lammer, Helmut; Stracke, Barbara; Gebauer, Stefanie; Schreier, Franz; Rauer, Heike

    2012-12-01

    Understanding whether M dwarf stars may host habitable planets with Earth-like atmospheres and biospheres is a major goal in exoplanet research. If such planets exist, the question remains as to whether they could be identified via spectral signatures of biomarkers. Such planets may be exposed to extreme intensities of cosmic rays that could perturb their atmospheric photochemistry. Here, we consider stellar activity of M dwarfs ranging from quiet up to strong flaring conditions and investigate one particular effect upon biomarkers, namely, the ability of secondary electrons caused by stellar cosmic rays to break up atmospheric molecular nitrogen (N(2)), which leads to production of nitrogen oxides (NO(x)) in the planetary atmosphere, hence affecting biomarkers such as ozone (O(3)). We apply a stationary model, that is, without a time dependence; hence we are calculating the limiting case where the atmospheric chemistry response time of the biomarkers is assumed to be slow and remains constant compared with rapid forcing by the impinging stellar flares. This point should be further explored in future work with time-dependent models. We estimate the NO(x) production using an air shower approach and evaluate the implications using a climate-chemical model of the planetary atmosphere. O(3) formation proceeds via the reaction O+O(2)+M→O(3)+M. At high NO(x) abundances, the O atoms arise mainly from NO(2) photolysis, whereas on Earth this occurs via the photolysis of molecular oxygen (O(2)). For the flaring case, O(3) is mainly destroyed via direct titration, NO+O(3)→NO(2)+O(2), and not via the familiar catalytic cycle photochemistry, which occurs on Earth. For scenarios with low O(3), Rayleigh scattering by the main atmospheric gases (O(2), N(2), and CO(2)) became more important for shielding the planetary surface from UV radiation. A major result of this work is that the biomarker O(3) survived all the stellar-activity scenarios considered except for the strong

  14. COSMIC RADIATION AND TUBERCULOSIS. IV. INFLUENCE OF COSMIC RADIATION ON TUBERCULOSIS AT HIGH ALTITUDE (3,130 M) AND AT SEA-LEVEL

    SciTech Connect

    Ong, S.G.

    1964-01-01

    At high altitude (3,130 m) tuberculous mice exposed to cosmic radiation under 10 cm of lead showed significantly greater mean survival time and a significantly greater number of survivors than tuberculous mice exposed to direct cosmic radiation. Tuberculous mice exposed to cosmic radiation at high altitude under 10 cm of lead showed a significantly greater mean survival time than tuberculous mice kept at sea level, exposed to direct cosmic radiation, and to cosmic radiation under 1, 2, and 10 cm of lead. The correlation analysis shows that a decreas in lung lesions is associated with an increase in survival time.more » The decrease in lung lesions is associated with an enlargement of the spleen. At high altitude the female showed a significantly greater number of survivors than the male. At sea level no significant difference was observed. On the average the female showed a significantly greater number of survivors. The beneficial effect of daylight with ultraviolet light on tuberculous mice was manifested in a lower maximum of mortality and in a significant decrease of lung and spleen lesions. (auth)« less

  15. Influence of accretion on lead in the Earth

    NASA Astrophysics Data System (ADS)

    Galer, Stephen J. G.; Goldstein, Steven L.

    The Pb abundance and isotope composition of the Earth is fundamentally altered from bulk solar system values by the processes occurring during accretion. The most important of the possible processes are volatile element loss and core formation, or some form of inhomogeneous accretion/condensation. The final result is an Earth highly impoverished in 204Pb and other Pb isotopes in primordial abundance. Depending on the exact timing, some radiogenic Pb is also lost either to space or to the core; the degree of loss occurs in the same order as the parent decay constants, namely 207Pb > 206Pb > 208Pb. In this contribution, we explore the likely effects accretion had on the Pb isotope composition of the present day bulk silicate Earth and its secular isotope evolution. This is used to address a number of questions: (1) What can be learned about accretion from the Pb isotope composition of the bulk silicate Earth? (2) Can effects of accretion reconcile the classical "Pb paradox" of a 206Pb-rich bulk silicate Earth? (3) What exactly is the meaning of the "age of the Earth" within the context of Pb isotopes? By consideration of a number of accretion scenarios it is demonstrated that Pb isotopes yield information only on the following two coupled quantities: Firstly, the accretion interval Δ T, the time between initial condensation of the solar nebula (at 4.566Ga) and when accretion-produced U/Pb fractionation (whether loss of Pb to the core or to space) in the silicate Earth ceased. Secondly, the mean 238U/204 Pb ratio μ during accretion—no details of changes in μ during the accretion interval can be resolved. The effects of accretion are thus adequately considered in terms of a simple two-stage model described by μ over ΔT followed by a postaccretion μ. The systematics of μ and ΔT are then examined for the cases of present day terrestrial reservoirs and Archean leads. These estimates of μ and ΔT for the present and past silicate Earth are not compatible with

  16. Cosmic-ray record in solar system matter

    NASA Technical Reports Server (NTRS)

    Reedy, R. C.; Arnold, J. R.; Lal, D.

    1983-01-01

    The interaction of galactic cosmic rays (GCR) and solar cosmic rays (SCR) with bodies in the solar system is discussed, and what the record of that interaction reveals about the history of the solar system is considered. The influence of the energy, charge, and mass of the particles on the interaction is addressed, showing long-term average fluxes of solar protons, predicted production rates for heavy-nuclei tracks and various radionuclides as a function of depth in lunar rock, and integral fluxes of protons emitted by solar flares. The variation of the earth's magnetic field, the gardening of the lunar surface, and the source of meteorites and cosmic dust are studied using the cosmic ray record. The time variation of GCR, SCR, and VH and VVH nuclei is discussed for both the short and the long term.

  17. Cosmic rays and other space weather effects influenced on satellite operation, technologies, biosphere and people health

    NASA Astrophysics Data System (ADS)

    Lev, Dorman

    2016-07-01

    Satellite anomalies (or malfunctions), including total distortion of electronics and loose of some satellites cost for Insurance Companies billions dollars per year. During especially active periods the probability of big satellite anomalies and their loosing increased very much. Now, when a great number of civil and military satellites are continuously worked for our practice life, the problem of satellite anomalies became very important. Many years ago about half of satellite anomalies were caused by technical reasons (for example, for Russian satellites Kosmos), but with time with increasing of production quality, this part became smaller and smaller. The other part, which now is dominated, caused by different space weather effects (energetic particles of CR and generated/trapped in the magnetosphere, and so on). We consider only satellite anomalies not caused by technical reasons: the total number of such anomalies about 6000 events, and separately for high and low altitude orbit satellites (5000 and about 800 events, correspondingly for high and low altitude satellites). No relation was found between low and high altitude satellite anomalies. Daily numbers of satellite anomalies, averaged by a superposed epoch method around sudden storm commencements and solar proton event onsets for high (>1500 km) and low (<1500 km) altitude orbits revealed a big difference in a behavior. Satellites were divided on several groups according to the orbital characteristics (altitude and inclination). The relation of satellite anomalies to the environmental parameters was found to be different for various orbits that should be taken into account under developing of the anomaly frequency models and forecasting. We consider also influence of CR on frequency of gene mutations and evolution of biosphere (we show that if it will be no CR, the Earth's civilization will be start only after milliards years later, what will be too late), CR role in thunderstorm phenomena and discharges

  18. The Influence of Ablation on Radiative Heating for Earth Entry

    NASA Technical Reports Server (NTRS)

    Johnston, Christopher O.; Gnoffo, Peter A.; Sutton, Kenneth

    2008-01-01

    Using the coupled ablation and radiation capability recently included in the LAURA flowfield solver, this paper investigates the influence of ablation on the shock-layer radiative heating for Earth entry. The extension of the HARA radiation model, which provides the radiation predictions in LAURA, to treat a gas consisting of the elements C, H, O, and N is discussed. It is shown that the absorption coefficient of air is increased with the introduction of the C and H elements. A simplified shock layer model is studied to show the impact of temperature, as well as the abundance of C and H, on the net absorption or emission from an ablation contaminated boundary layer. It is found that the ablation species reduce the radiative flux in the vacuum ultraviolet, through increased absorption, for all temperatures. However, in the infrared region of the spectrum, the ablation species increase the radiative flux, through strong emission, for temperatures above 3,000 K. Thus, depending on the temperature and abundance of ablation species, the contaminated boundary layer may either provide a net increase or decrease in the radiative flux reaching the wall. To assess the validity of the coupled ablation and radiation LAURA analysis, a previously analyzed Mars-return case (15.24 km/s), which contains significant ablation and radiation coupling, is studied. Exceptional agreement with previous viscous shock-layer results is obtained. A 40% decrease in the radiative flux is predicted for ablation rates equal to 20% of the free-stream mass flux. The Apollo 4 peak-heating case (10.24 km/s) is also studied. For ablation rates up to 3.4% of the free-stream mass flux, the radiative heating is reduced by up to 19%, while the convective heating is reduced by up to 87%. Good agreement with the Apollo 4 radiometer data is obtained by considering absorption in the radiometer cavity. For both the Mars return and the Apollo 4 cases, coupled radiation alone is found to reduce the radiative

  19. The Earth Education Program Sunship™ Earth: A Mixed Methods Study of the Long-Term Influence on Environmental Attitudes and Actions

    ERIC Educational Resources Information Center

    Bires, Nancy K.

    2013-01-01

    There have been a limited number of studies on the short-term influence of environmental and earth education programs, however, not much information is available about the long-term influence of these programs on participants' environmental attitudes and actions. This mixed methods study explores the long-term influence of the earth education…

  20. Influence of clouds on the cosmic radiation dose rate on aircraft.

    PubMed

    Pazianotto, Maurício T; Federico, Claudio A; Cortés-Giraldo, Miguel A; Pinto, Marcos Luiz de A; Gonçalez, Odair L; Quesada, José Manuel M; Carlson, Brett V; Palomo, Francisco R

    2014-10-01

    Flight missions were made in Brazilian territory in 2009 and 2011 with the aim of measuring the cosmic radiation dose rate incident on aircraft in the South Atlantic Magnetic Anomaly and to compare it with Monte Carlo simulations. During one of these flights, small fluctuations were observed in the vicinity of the aircraft with formation of Cumulonimbus clouds. Motivated by these observations, in this work, the authors investigated the relationship between the presence of clouds and the neutron flux and dose rate incident on aircraft using computational simulation. The Monte Carlo simulations were made using the MCNPX and Geant4 codes, considering the incident proton flux at the top of the atmosphere and its propagation and neutron production through several vertically arranged slabs, which were modelled according to the ISO specifications. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. An Empirical Modification of the Force Field Approach to Describe the Modulation of Galactic Cosmic Rays Close to Earth in a Broad Range of Rigidities

    NASA Astrophysics Data System (ADS)

    Gieseler, J.; Heber, B.; Herbst, K.

    2017-11-01

    On their way through the heliosphere, galactic cosmic rays (GCRs) are modulated by various effects before they can be detected at Earth. This process can be described by the Parker equation, which calculates the phase space distribution of GCRs depending on the main modulation processes: convection, drifts, diffusion, and adiabatic energy changes. A first-order approximation of this equation is the force field approach, reducing it to a one-parameter dependency, the solar modulation potential ϕ. Utilizing this approach, it is possible to reconstruct ϕ from ground-based and spacecraft measurements. However, it has been shown previously that ϕ depends not only on the local interstellar spectrum (LIS) but also on the energy range of interest. We have investigated this energy dependence further, using published proton intensity spectra obtained by PAMELA and heavier nuclei measurements from IMP-8 and ACE/CRIS. Our results show severe limitations at lower energies including a strong dependence on the solar magnetic epoch. Based on these findings, we will outline a new tool to describe GCR proton spectra in the energy range from a few hundred MeV to tens of GeV over the last solar cycles. In order to show the importance of our modification, we calculate the global production rates of the cosmogenic radionuclide 10Be which is a proxy for the solar activity ranging back thousands of years.

  2. Calibration of impact ionization cosmic dust detectors: first tests to investigate how the dust density influences the signal

    NASA Astrophysics Data System (ADS)

    Jasmin Sterken, Veerle; Moragas-Klostermeyer, Georg; Hillier, Jon; Fielding, Lee; Lovett, Joseph; Armes, Steven; Fechler, Nina; Srama, Ralf; Bugiel, Sebastian; Hornung, Klaus

    2016-10-01

    Impact ionization experiments have been performed since more than 40 years for calibrating cosmic dust detectors. A linear Van de Graaff dust accelerator was used to accelerate the cosmic dust analogues of submicron to micron-size to speeds up to 80 km s^-1. Different materials have been used for calibration: iron, carbon, metal-coated minerals and most recently, minerals coated with conductive polymers. While different materials with different densities have been used for instrument calibration, a comparative analysis of dust impacts of equal material but different density is necessary: porous or aggregate-like particles are increasingly found to be present in the solar system: e.g. dust from comet 67P Churyumov-Gerasimenko [Fulle et al 2015], aggregate particles from the plumes of Enceladus [Gao et al 2016], and low-density interstellar dust [Westphal 2014 et al, Sterken et al 2015]. These recalibrations are relevant for measuring the size distributions of interplanetary and interstellar dust and thus mass budgets like the gas-to-dust mass ratio in the local interstellar cloud.We report about the calibrations that have been performed at the Heidelberg dust accelerator facility for investigating the influence of particle density on the impact ionization charge. We used the Cassini Cosmic Dust Analyzer for the target, and compared hollow versus compact silica particles in our study as a first attempt to investigate experimentally the influence of dust density on the signals obtained. Also, preliminary tests with carbon aerogel were performed, and (unsuccessful) attempts to accelerate silica aerogel. In this talk we explain the motivation of the study, the experiment set-up, the preparation of — and the materials used, the results and plans and recommendations for future tests.Fulle, M. et al 2015, The Astrophysical Journal Letters, Volume 802, Issue 1, article id. L12, 5 pp. (2015)Gao, P. et al 2016, Icarus, Volume 264, p. 227-238Westphal, A. et al 2014, Science

  3. Investigation of the basic characteristics of electrostatic shielding from cosmic radiations on the artificial earth satellite Kosmos 605. I. Measurement procedure and the complex of scientific apparatus. [1. 4 x 10/sup 7/ V/m

    SciTech Connect

    Kovalev, E.E.; Molchanov, E.D.; Pekhterev, Yu.G.

    1975-01-01

    The complex of scientific apparatus installed on board the artifical earth satellite Kosmos 605 for the creation of electric fields near the satellite with intensities up to 1.4 x 10/sup 7/ V/m and for direct measurements of conduction currents of a high voltage vacuum interval for the purpose of determining the basic characteristics of electrostatic shielding from cosmic radiations is described.

  4. Our Cosmic Connection

    ERIC Educational Resources Information Center

    Young, Donna L.

    2005-01-01

    To help students understand the connection that Earth and the solar system have with the cosmic cycles of stellar evolution, and to give students an appreciation of the beauty and elegance of celestial phenomena, the Chandra X-Ray Center (CXC) educational website contains a stellar evolution module that is available free to teachers. In this…

  5. COSMIC RADIATION AND TUBERCULOSIS. V. INFLUENCE OF COSMIC RADIATION ON TUBERCULOSIS AT HIGH ALTITUDE (2,300m) AND AT SEA-LEVEL

    SciTech Connect

    Ong, S.G.

    1964-02-01

    Tuberculous mice exposed to cosmic radiation at 2,300 m showed a significantly greater mean survival time and a significantly greater number of survivors than tuberculous mice exposed to cosmic radiation at sea-level. At high altitude as well as at sea-level the female showed a significantly greater mean survival than the male. The mean survival time of the male or female at high altitude is significantly greater than that of the male or female at sealevel. At high altitude there is no significant difference in montality between male and female. At sea-level the female showed a significantly greater number of survivorsmore » than the male. The pooled data showed a significantly greater number of survivors of the female. At high altitude as well as at sea- level the lung lesions diminished, whereas the spleen lesions increased significantly with increasing survival time. (auth)« less

  6. Consistency of cosmic-ray source abudances with explosive nucleosynthesis

    NASA Technical Reports Server (NTRS)

    Kozlovsky, B.; Ramaty, R.

    1973-01-01

    A model was examined in which the cosmic ray abundances of elements from C to Fe are consistent with explosive nucleosynthesis. The observed abundance of cosmic rays near the earth, cosmic ray source abundance, and solar system abundance are discussed along with the ratios of cosmic ray sources to the solar system abundances.

  7. Approximate likelihood approaches for detecting the influence of primordial gravitational waves in cosmic microwave background polarization

    NASA Astrophysics Data System (ADS)

    Pan, Zhen; Anderes, Ethan; Knox, Lloyd

    2018-05-01

    One of the major targets for next-generation cosmic microwave background (CMB) experiments is the detection of the primordial B-mode signal. Planning is under way for Stage-IV experiments that are projected to have instrumental noise small enough to make lensing and foregrounds the dominant source of uncertainty for estimating the tensor-to-scalar ratio r from polarization maps. This makes delensing a crucial part of future CMB polarization science. In this paper we present a likelihood method for estimating the tensor-to-scalar ratio r from CMB polarization observations, which combines the benefits of a full-scale likelihood approach with the tractability of the quadratic delensing technique. This method is a pixel space, all order likelihood analysis of the quadratic delensed B modes, and it essentially builds upon the quadratic delenser by taking into account all order lensing and pixel space anomalies. Its tractability relies on a crucial factorization of the pixel space covariance matrix of the polarization observations which allows one to compute the full Gaussian approximate likelihood profile, as a function of r , at the same computational cost of a single likelihood evaluation.

  8. THE INFLUENCE OF DISSIPATION RANGE POWER SPECTRA AND PLASMA-WAVE POLARIZATION ON COSMIC-RAY SCATTERING MEAN FREE PATH

    SciTech Connect

    Schlickeiser, R.; Lazar, M.; Vukcevic, M., E-mail: rsch@tp4.rub.d, E-mail: mlazar@tp4.ruhr-uni-bochum.d, E-mail: vuk.mira@gmail.co

    2010-08-20

    The influence of the polarization state and the dissipation range spectral steepening of slab plasma waves on the scattering mean free path of single-charged cosmic-ray particles is investigated in a turbulence model, where the crucial scattering of cosmic-ray particles with small pitch-angle cosines is caused by resonant cyclotron interactions with slab plasma waves. Analytical expressions for the mean free path of protons, antiprotons, negatrons, and positrons are derived for the case of constant frequency-independent magnetic helicity values {sigma} and different values of the dissipation range spectral index k for characteristic interplanetary and interstellar plasma conditions. The positron mean free pathmore » is not affected by the dissipation range spectral index k as these particles can only cyclotron-resonate for rigidity values larger than R {sub 0} = m{sub p}c = 938 MV. Proton and antiproton mean free paths are only slightly affected by the dissipation range spectral index k at small rigidities R < R {sub 0}. The negatron mean free path is severely affected by the dissipation range spectral index k at rigidities smaller than R {sub 0}. At high rigidities R >> R {sub 0}, all particle species approach the same power-law dependence {proportional_to}R {sup 2-s} determined by the inertial range spectral index s = 5/3. The magnetic helicity value {sigma} affects the value of the mean free path. At all rigidities, the ratio of the antiproton to proton mean free paths equals the constant (1 + {sigma})/(1 - {sigma}), which also agrees with the ratio of the negatron to the proton and positron mean free paths at relativistic rigidities. At relativistic rigidities the positron and proton mean free paths agree, as do the negatron and antiproton mean free paths.« less

  9. Earth's magnetic field as a radiator to detet cosmic ray electrons of energy >10/sup 12/ eV

    SciTech Connect

    Stephens, S.A.; Balasubrahmanyan, V.K.

    1983-10-01

    We have examined in detail the synchrotron emission by electrons of energy greater than a few TeV in the earth's magnetic field. The photon spectrum lies in the X-ray and ..gamma.. ray region. As the emission takes place in a narrow cone along the direction of the electron, the photons would be incident nearly along a straight line on a detector. This unique feature provides the signature to identify the electron unambiguously. The mean energy of the photons being proportional to the square of the electron energy allows us to determine the energy accurately. Though it may appear that onemore » needs to know the arrival direction of electrons to obtain its energy, we have shown that an omnidirectional detector can be satisfactorily used to estimate the energy. We also show that the colleting power of the detector is a sensitive function of the area of the detector A, the energy of electron E/sub 0/, and the number of photons required to identify an electron n/sub ..gamma../; asymptotically the collecting power is proportional to A/sup 1.43/ E/sub 0/n/sub ..gamma..//sup -1.8/. An instrument, with an energy threshold for the detection of photons can be used to measure reliably the integral flux of electrons, even if it has limited energy resolution. We have calculated the event rate expected by using an ideal balloon-borne detector capable of detecting above 20 keV at 4 g cm/sup -2/ of atmospheric depth over Palestine Texas, and compared with the expected rates using instruments based on currently available techniques of detection.« less

  10. Analysis of gamma radiation from a radon source. II: Indications of influences of both solar and cosmic neutrinos on beta decays

    NASA Astrophysics Data System (ADS)

    Sturrock, P. A.; Steinitz, G.; Fischbach, E.

    2018-07-01

    In the first article in this series, we reported an analysis of 29,000 hourly measurements of gamma radiation associated with the decay of radon gas in a sealed container at the Geological Survey of Israel (GSI) Laboratory in Jerusalem (Sturrock et al., 2012). We now report an analysis of a full 10 years of operation that yields over 85,000 hourly gamma measurements. To avoid possible confusion with seasonal environmental influences, we pay special attention to oscillations with frequencies in a band relevant to solar rotation, identifying two striking oscillations with frequencies 11.35 year-1 and 12.63 year-1, which we have found to be prominent also in decay data acquired at the Brookhaven National Laboratory (Sturrock et al., 2016). The 12.63 year-1 frequency agrees with the synodic rotational frequency (the frequency as observed on Earth) of the radiative zone as determined by helioseismology. Significantly, the more prominent rotational oscillations occur in pairs separated by 1 year-1, indicating that the solar sources of modulation rotate about axes that are oblique with respect to the normal to the ecliptic. It is notable that one of a triplet of such oscillations has exactly the same frequency (9.43 year-1) as the most significant oscillation in Super-Kamiokande measurements, suggesting that the experiment is responding to the influence of neutrinos. As found in our previous article, the annual oscillation is (counter-intuitively) stronger by day (with phase of maximum near 0.5, i.e. mid-year, suggestive of a cosmic source) than by night (with phase of maximum near zero, as expected for a solar source). This day-night asymmetry in the measurements may be understood in terms of a combined influence of asymmetries in the experiment and in the relevant nuclear processes. Spectrograms (with axes local hour of day and frequency) formed from the ambient temperature and pressure and the supply voltage differ significantly from the corresponding spectrogram

  11. COSMIC RAYS AND COSMIC SPACE (in Russian)

    SciTech Connect

    Vernova, S.N.

    1960-08-01

    An account is given of recent studies of cosmic rays utilizing both earthbound stations and artificial earth satellites. Phenomena recently uncovered by sputniks are described. A description is given of the cosmic ray laboratory of Moscow University. A particle possessing an energy of l0/sup 15/ ev was detected and the equipment and procedure by which this was done are described. mu mesons in a particle shower produced by cosmic rays were detected at a depth of thirty meters underground. The apparatus required in the sputriks for the study of cosmic rays outside the earth's atmosphere is discussed. The equipment inmore » the sputniks launched to date was transistorized; scintillation counters were used to determine particle energies. A description is given of the large burst of radiation detected by the second sputnik on Nov. 7, 1957. This burst was observed only at latitudes of about 50 to 70 degrees north latitude. The third sputnik had a scintillation counter of high sensitivity which detected relatively weak fluxes of electrons. This equipment fixed the location of the high intensity radiation belt around the earth. A typical graph of count rate and energy current versus geographic location is given. Data are given that indicate the coincidence of peak radiation intensities with those regions where the aurora borealis is seen. The radiation belt extends up to approximately 60,000 km from the earth's surface and is bounded by the magnetic lines of force that intersect the earth' s surface at geomagnetic latitudes of 55 deg and 70 deg . The earth's magnetic field traps these particles and holds them in an orbit that follows magnetic lines of force and oscillates from the northern to the southern hemisphere for long periods of time. A diagram is given of the trajectory of the first Soviet cosmic rocket and changes in radiation intensity along this trajectory are indicated. A maximum radiation intensity was detected at a distance of 20,000 km from the earth

  12. Earth

    NASA Image and Video Library

    2012-01-30

    Behold one of the more detailed images of the Earth yet created. This Blue Marble Earth montage shown above -- created from photographs taken by the Visible/Infrared Imager Radiometer Suite (VIIRS) instrument on board the new Suomi NPP satellite -- shows many stunning details of our home planet. The Suomi NPP satellite was launched last October and renamed last week after Verner Suomi, commonly deemed the father of satellite meteorology. The composite was created from the data collected during four orbits of the robotic satellite taken earlier this month and digitally projected onto the globe. Many features of North America and the Western Hemisphere are particularly visible on a high resolution version of the image. http://photojournal.jpl.nasa.gov/catalog/PIA18033

  13. Solar flare induced cosmic noise absorption

    NASA Astrophysics Data System (ADS)

    Ogunmodimu, Olugbenga; Honary, Farideh; Rogers, Neil; Falayi, E. O.; Bolaji, O. S.

    2018-06-01

    Solar flare events are a major observing emphasis for space weather because they affect the ionosphere and can eject high-energy particles that can adversely affect Earth's technologies. In this study we model 38.2 MHz cosmic noise absorption (CNA) by utilising measurements from the Imaging Riometer for Ionospheric Studies (IRIS) at Kilpisjärvi, Finland obtained during solar cycle 23 (1996-2009). We utilised X-ray archive for the same period from the Geostationary Operational Environmental Satellite (GOES) to study solar flare induced cosmic noise absorption. We identified the threshold of flare (M4 class) that could bear significant influence on CNA. Through epoch analysis, we show the magnitude of absorption that each class of flare could produce. Using the parameters of flare and absorption we present a model that could provide the basis for nowcast of CNA induced by M and X-class solar flares.

  14. Cosmic ray topography

    NASA Astrophysics Data System (ADS)

    Bressler, Matthew; Goodwin, Lydia; Kryemadhi, Abaz

    2017-11-01

    Cosmic ray muons are produced when high energy particles interact with nuclei in Earth's atmosphere. Muons make up the majority of charged particles that reach sea level and are the only particles (apart from neutrinos) that can penetrate to significant depths underground. The muon flux underground decreases approximately exponentially as a function of depth. We use a cosmic ray detector developed by the QuarkNet Program at Fermi National Laboratory to map the topography of the mountain above an abandoned Pennsylvania Turnpike tunnel by analyzing muon flux at different rock overburdens. Cosmic ray muons have been used in this capacity before to search for hidden chambers in pyramids and for mapping volcanoes. This study provides a unique field experience to learn about particle physics and particle detectors, which could be of interest to students and teachers in physics.

  15. Cosmic-Ray Source Composition Determined from ACE

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, M.

    2000-01-01

    The cosmic rays arriving at Earth comprise a mix of material produced by stellar sources and ejected into the interstellar medium (primary cosmic rays) and particles produced by fragmentation of heavier nuclei during transport through the Galaxy.

  16. Cosmic Radiation | RadTown USA | US EPA

    EPA Pesticide Factsheets

    2017-08-07

    Radiation from space is constantly hitting the Earth. Radiation from space is called cosmic radiation. Cosmic radiation makes up about five percent of annual radiation exposure of an average person in the United States.

  17. The Origin of Cosmic Rays

    ScienceCinema

    Blasi, Pasquale

    2017-12-22

    Cosmic Rays reach the Earth from space with energies of up to more than 1020 eV, carrying information on the most powerful particle accelerators that Nature has been able to assemble. Understanding where and how cosmic rays originate has required almost one century of investigations, and, although the last word is not written yet, recent observations and theory seem now to fit together to provide us with a global picture of the origin of cosmic rays of unprecedented clarity. Here we will describe what we learned from recent observations of astrophysical sources (such as supernova remnants and active galaxies) and we will illustrate what these observations tell us about the physics of particle acceleration and transport. We will also discuss the “end” of the Galactic cosmic ray spectrum, which bridges out attention towards the so called ultra high energy cosmic rays (UHECRs). At ~1020 eV the gyration scale of cosmic rays in cosmic magnetic fields becomes large enough to allow us to point back to their sources, thereby allowing us to perform “cosmic ray astronomy”, as confirmed by the recent results obtained with the Pierre Auger Observatory. We will discuss the implications of these observations for the understanding of UHECRs, as well as some questions which will likely remain unanswered and will be the target of the next generation of cosmic ray experiments.

  18. Carl Sagan's Cosmic Connection

    NASA Astrophysics Data System (ADS)

    Sagan, Carl; Agel, Jerome

    2000-08-01

    Foreword Freeman Dyson; Personal reflections Ann Druyan; Preface; Part I. Cosmic Perspective: 1. A transitional animal; 2. The Unicorn of Cetus; 3. A message from earth; 4. A message to earth; 5. Experiments in utopias; 6. Chauvinism; 7. Space exploration as a human enterprise I. The scientific interest; 8. Space exploration as a human enterprise II. The public interest; 9. Space exploration as a human enterprise III. The historical interest; Part II. The Solar System: 10. On teaching the first grade; 11. 'The ancient and legendary Gods of old'; 12. The Venus detective story; 13. Venus is hell; 14. Science and 'intelligence'; 15. The moons of Barsoom; 16. The mountains of Mars I. Observations from earth; 17. The mountains of Mars II. Observations from space; 18. The canals of Mars; 19. The lost pictures of Mars; 20. The Ice Age and the cauldron; 21. Beginnings and ends of the Earth; 22. Terraforming the plants; 23. The exploration and utlization of the solar system; Part III. Beyond the Solar System: 24. Some of my best friends are dolphins; 25. 'Hello, central casting? Send me twenty extraterrestrials'; 26. The cosmic connection; 27. Extraterrestrial life: an idea whose time has come; 28. Has the Earth been visited?; 29. A search strategy for detecting extraterrestrial intelligence; 30. If we succeed 31. Cables, drums, and seashells; 32. The night freight to the stars; 33. Astroengineering; 34. Twenty questions: a classification of cosmic civilisations; 35. Galactic cultural exchanges; 36. A passage to elsewhere; 37. Starfolk I. A Fable; 38. Starfolk II. A future; 39. Starfolk III. The cosmic Cheshire cats; Epilog David Morrison; Index.

  19. The Emergence of Cosmic Education. Spotlight: Cosmic Education.

    ERIC Educational Resources Information Center

    Trudeau, Sr. Christina Marie

    2002-01-01

    Discusses the influence of Hindu, Moslem, and Buddhist metaphysics on Maria Montessori's own pedagogical philosophy of Cosmic Education, which she regarded as the core of all learning experiences, after her visit to India. Considers the relationship between Montessori's ideas of child development and Cosmic Education, and the effect of Indian…

  20. Influence of Earth-directed Coronal Mass Ejections on the Sun’s Shadow Observed by the Tibet-III Air Shower Array

    NASA Astrophysics Data System (ADS)

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

    2018-06-01

    We examine the possible influence of Earth-directed coronal mass ejections (ECMEs) on the Sun’s shadow in the 3 TeV cosmic-ray intensity observed by the Tibet-III air shower (AS) array. We confirm a clear solar-cycle variation of the intensity deficit in the Sun’s shadow during ten years between 2000 and 2009. This solar-cycle variation is overall reproduced by our Monte Carlo (MC) simulations of the Sun’s shadow based on the potential field model of the solar magnetic field averaged over each solar rotation period. We find, however, that the magnitude of the observed intensity deficit in the Sun’s shadow is significantly less than that predicted by MC simulations, particularly during the period around solar maximum when a significant number of ECMEs is recorded. The χ 2 tests of the agreement between the observations and the MC simulations show that the difference is larger during the periods when the ECMEs occur, and the difference is reduced if the periods of ECMEs are excluded from the analysis. This suggests the first experimental evidence of the ECMEs affecting the Sun’s shadow observed in the 3 TeV cosmic-ray intensity.

  1. Superbubbles and Local Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Streitmatter, Robert E.; Jones, Frank C.

    2005-01-01

    We consider the possibility that distinctive features of the local cosmic ray spectra and composition are influenced by the Solar system being embedded within the cavity of an ancient superbubble. Shifts in the measured cosmic ray composition between 10(exp 11) and 10(exp 20) eV as well as the "knee" and "second knee" may be understood in this picture.

  2. Gravitationally influenced particle creation models and late-time cosmic acceleration

    NASA Astrophysics Data System (ADS)

    Pan, Supriya; Kumar Pal, Barun; Pramanik, Souvik

    In this work, we focus on the gravitationally influenced adiabatic particle creation process, a mechanism that does not need any dark energy or modified gravity models to explain the current accelerating phase of the universe. Introducing some particle creation models that generalize some previous models in the literature, we constrain the cosmological scenarios using the latest compilation of the Type Ia Supernovae data only, the first indicator of the accelerating universe. Aside from the observational constraints on the models, we examine the models using two model independent diagnoses, namely the cosmography and Om. Further, we establish the general conditions to test the thermodynamic viabilities of any particle creation model. Our analysis shows that at late-time, the models have close resemblance to that of the ΛCDM cosmology, and the models always satisfy the generalized second law of thermodynamics under certain conditions.

  3. Extrusive and Intrusive Magmatism Greatly Influence the Tectonic Mode of Earth-Like Planets

    NASA Astrophysics Data System (ADS)

    Lourenco, D.; Tackley, P. J.; Rozel, A.; Ballmer, M.

    2017-09-01

    Plate tectonics on Earth-like planets is typically modelling using a strongly temperature-dependent visco-plastic rheology. Previous analyses have generally focussed on purely thermal convection. However, we have shown that the influence of compositional heterogeneity in the form of continental or oceanic crust can greatly influence plate tectonics by making it easier (i.e. it occurs at a lower yield stress or friction coefficient). Here we present detailed results on this topic, in particular focussing on the influence of intrusive vs. extrusive magmatism on the tectonic mode.

  4. Cosmic Rays as a Factor of Biosphere Evolution

    NASA Astrophysics Data System (ADS)

    Miroshnichenko, L. I.

    2014-11-01

    There are no doubts that the Earth's space environment in the past inevitably exerted direct and/or indirect influence [1--4] on the conditions of terrestrial life and biospheric evolution. Well-known cosmic factors are usually streams of cosmic dust and gas, comets and asteroids, cosmic rays (energetic particles of galactic and/or solar origin), interplanetary plasma (solar wind), and electromagnetic radiation of different energies, wavelengths, or frequencies. Of great interest are radiation conditions and their variations, especially in the remote past (over the geological time scales). The Sun, the most important and indispensable condition for the existence of the Earth's biosphere, is also a potential source of dangerous emissions. In continuation of (and in addition to) our review paper [3], below we summarize the observational data and results of theoretical works that have been carried out and/or published mainly after 2012. These studies are actually in the frontier region between the Astrobiology and Space Weather. Our main attention is paid to cosmic rays (CR) of galactic and solar origin (GCR and SCR, respectively).

  5. The influence of nonstationarity of the solar activity and general solar field on modulation of cosmic rays

    NASA Technical Reports Server (NTRS)

    Zusmanovich, A. G.; Kryakunova, O. N.; Churunova, L. F.; Shvartsman, Y. E.

    1985-01-01

    A numerical model of the propagation of galactic cosmic rays in interplanetary space was constructed for the case when the modulation depth determined by the level of solar activity changed in time. Also the contribution of particle drift in the regular field was calculated, and the agreement with experimental data concerning the ratio of protons and electrons in two solar activity minima is shown.

  6. Cosmic Background Explorer (COBE) press kit

    NASA Technical Reports Server (NTRS)

    1989-01-01

    COBE, the Cosmic Background Explorer spacecraft, and its mission are described. COBE was designed to study the origin and dynamics of the universe including the theory that the universe began with a cataclysmic explosion referred to as the Big Bang. To this end, earth's cosmic background - the infrared radiation that bombards earth from every direction - will be measured by three sophisticated instruments: the Differential Microwave Radiometer (DMR), the Far Infrared Absolute Spectrophotometer (FIRAS), and the Diffuse Infrared Background Experiment (DIRBE).

  7. Earth's magnetic field as a radiator to detect cosmic ray electrons of energy greater than 10 to the 12th eV

    NASA Technical Reports Server (NTRS)

    Balasubrahmanyan, V. K.; Stephens, S. A.

    1983-01-01

    Synchrotron emission by a high-energy electron in the geomagnetic field and its dependence upon different arrival directions over Palestine, Texas, where major balloon-borne experiments are being conducted, is studied. The dependence of detector response on the arrival direction of electron, the different criteria which are adopted to identify an electron event, the area of the detector, and the energy of the electron are discussed. An omnidirectional circular detector is used to examine whether it is possible to determine the energy of an electron without knowing its arrival direction. The collecting power of a detector is estimated as a function of the energy of electrons for different detector areas with different selection criteria, and this information is used to calculate the event rates expected by folding in the energy spectrum of cosmic ray electrons to show the viability of detecting cosmic ray electrons at energies greater than a few TeV.

  8. Cosmic strings

    NASA Technical Reports Server (NTRS)

    Bennett, David P.

    1988-01-01

    Cosmic strings are linear topological defects which are predicted by some grand unified theories to form during a spontaneous symmetry breaking phase transition in the early universe. They are the basis for the only theories of galaxy formation aside from quantum fluctuations from inflation based on fundamental physics. In contrast to inflation, they can also be observed directly through gravitational lensing and their characterisitc microwave background anisotropy. It was recently discovered that details of cosmic string evolution are very differnt from the so-called standard model that was assumed in most of the string-induced galaxy formation calculations. Therefore, the details of galaxy formation in the cosmic string models are currently very uncertain.

  9. Cosmic Complexity

    NASA Technical Reports Server (NTRS)

    Mather, John C.

    2012-01-01

    neutrons, liberating a little energy and creating complexity. Then, the expanding universe cooled some more, and neutrons and protons, no longer kept apart by immense temperatures, found themselves unstable and formed helium nuclei. Then, a little more cooling, and atomic nuclei and electrons were no longer kept apart, and the universe became transparent. Then a little more cooling, and the next instability began: gravitation pulled matter together across cosmic distances to form stars and galaxies. This instability is described as a "negative heat capadty" in which extracting energy from a gravitating system makes it hotter -- clearly the 2nd law of thermodynamics does not apply here! (This is the physicist's part of the answer to e e cummings' question: what is the wonder that's keeping the stars apart?) Then, the next instability is that hydrogen and helium nuclei can fuse together to release energy and make stars burn for billions of years. And then at the end of the fuel source, stars become unstable and explode and liberate the chemical elements back into space. And because of that, on planets like Earth, sustained energy flows support the development of additional instabilities and all kinds of complex patterns. Gravitational instability pulls the densest materials into the core of the Earth, leaving a thin skin of water and air, and makes the interior churn incessantly as heat flows outwards. And the heat from the sun, received mostly near the equator and flowing towards the poles, supports the complex atmospheric and oceanic circulations. And because or that, the physical Earth is full of natural chemical laboratories, concentrating elements here, mixing them there, raising and lowering temperatures, ceaselessly experimenting with uncountable events where new instabilities can arise. At least one of them was the new experiment called life. Now that we know that there are at least as many planets as there are stars, it is hard to imagine that nature's ceasess

  10. Long-Term Solar and Cosmic Radiation Data Bases

    DTIC Science & Technology

    1991-01-01

    determine the magnitude of the variations in the cosmic ray intensity caused by solar activity. Neutron monitors, with their much lower energy threshold...expression that neutron monitors are sensors on spacecraft EARTH. Here we will consider cosmic ray detectors to measure two components of cosmic ...A comparison with the solar cycle as illustrated by the sunspot number in Fig. 1. shows that the maximum cosmic ray intensity occurs near sunspot

  11. THE COSMIC RAY EQUATOR AND THE GEOMAGNETISM

    SciTech Connect

    Sakurai, K.

    1960-01-01

    It was formerly thought that the disagreement of the position of geomagnetic dipole equator with that of the cosmic ray equator was caused by 45 deg westward shifting of the latter. Referring to the theory of geomagnetic effect on cosmic rays, it was determined whether such westward shifting could be existent or not. It was found that the deviation of the cosmic ray equator from the geomagnetic dipole equator is negligible even if the magnetic cavity is present around the earth's outer atmosphere. Taking into account such results, the origin of the cosmic ray equator was investigated. It was foundmore » that this equater could be produced by the higher harmonic components combined with the dipole component of geomagnetism. The relation of the origin of the cosmic ray equater to the eccentric dipoles, near the outer pant of the earth's core, contributing to the secular variation of geomagnetism was considered. (auth)« less

  12. Cosmic Balloons

    ERIC Educational Resources Information Center

    El Abed, Mohamed

    2014-01-01

    A team of French high-school students sent a weather balloon into the upper atmosphere to recreate Viktor Hess's historical experiment that demonstrated the existence of ionizing radiation from the sky--later called cosmic radiation. This discovery earned him the Nobel Prize for Physics in 1936.

  13. Lunisolar Tides Influence on Electrical Conductivity of the Earth's Crust in the Territory of Kola Peninsula

    NASA Astrophysics Data System (ADS)

    Zhamaletdinov, A. A.; Shevtsov, A. N.; Korotkova, T. G.

    2018-05-01

    The results of studying the influence of lunisolar tides on the electrical conductivity of the Earth's crust in the territory of the Kola Peninsula are presented. Along with the results obtained by the authors, the data of other researchers are also considered. All the studies are based on the analysis of the field produced by the Zevs facility transmitting extremely low frequency (ELF) signals at 82-83 Hz. The measurements were carried out in different years at the Avva-Guba (1998), Lovozero (2009), and Imandra-Varzuga polygon (IVP) monitoring sites (2013) located 180, 90, and 160 km from the transmitter, respectively. The negative correlation between the tides and crustal electrical resistivity is revealed at all the points. This means that tidal rises of the Earth's surface are accompanied by a decrease in resistivity and vice versa. The overview shows that the higher the resistivity of separate Earth's crustal blocks the higher the relative amplitudes of the corresponding tidal responses that are observed.

  14. Monitoring cosmic radiation on aircraft

    NASA Astrophysics Data System (ADS)

    Bentley, Robert D.; Iles, R. H. A.; Jones, J. B. L.; Hunter, R.; Taylor, G. C.; Thomas, D. J.

    2002-03-01

    The Earth is constantly bombarded by cosmic radiation that can be either galactic or solar in origin. At aircraft altitudes, the radiation levels are much higher than at sea level and recent European legislation has classified aircrew as radiation workers. University College London is working with Virgin Atlantic Airways on a 3 year project to monitor the levels of cosmic radiation on long-haul flights. The study will determine whether models currently used to predict radiation exposure of aircrew are adequate. It will also try to determine whether solar flare activity can cause significant enhancement to the predicted doses.

  15. Cosmic jets

    NASA Technical Reports Server (NTRS)

    Rees, M. J.

    1986-01-01

    The evidence that active galactic nuclei produce collimated plasma jets is summarised. The strongest radio galaxies are probably energised by relativistic plasma jets generated by spinning black holes interacting with magnetic fields attached to infalling matter. Such objects can produce e(+)-e(-) plasma, and may be relevant to the acceleration of the highest-energy cosmic ray primaries. Small-scale counterparts of the jet phenomenon within our own galaxy are briefly reviewed.

  16. Cosmic Topology

    NASA Astrophysics Data System (ADS)

    Luminet, Jean-Pierre

    2015-08-01

    Cosmic Topology is the name given to the study of the overall shape of the universe, which involves both global topological features and more local geometrical properties such as curvature. Whether space is finite or infinite, simply-connected or multi-connected like a torus, smaller or greater than the portion of the universe that we can directly observe, are questions that refer to topology rather than curvature. A striking feature of some relativistic, multi-connected "small" universe models is to create multiples images of faraway cosmic sources. While the most recent cosmological data fit the simplest model of a zero-curvature, infinite space model, they are also consistent with compact topologies of the three homogeneous and isotropic geometries of constant curvature, such as, for instance, the spherical Poincaré Dodecahedral Space, the flat hypertorus or the hyperbolic Picard horn. After a "dark age" period, the field of Cosmic Topology has recently become one of the major concerns in cosmology, not only for theorists but also for observational astronomers, leaving open a number of unsolved issues.

  17. The influence of lateral Earth structure on glacial isostatic adjustment in Greenland

    NASA Astrophysics Data System (ADS)

    Milne, Glenn A.; Latychev, Konstantin; Schaeffer, Andrew; Crowley, John W.; Lecavalier, Benoit S.; Audette, Alexandre

    2018-05-01

    We present the first results that focus on the influence of lateral Earth structure on Greenland glacial isostatic adjustment (GIA) using a model that can explicitly incorporate 3-D Earth structure. In total, eight realisations of lateral viscosity structure were developed using four global seismic velocity models and two global lithosphere (elastic) thickness models. Our results show that lateral viscosity structure has a significant influence on model output of both deglacial relative sea level (RSL) changes and present-day rates of vertical land motion. For example, lateral structure changes the RSL predictions in the Holocene by several 10 s of metres in many locations relative to the 1-D case. Modelled rates of vertical land motion are also significantly affected, with differences from the 1-D case commonly at the mm/yr level and exceeding 2 mm/yr in some locations. The addition of lateral structure was unable to account for previously identified data-model RSL misfits in northern and southern Greenland, suggesting limitations in the adopted ice model (Lecavalier et al. 2014) and/or the existence of processes not included in our model. Our results show large data-model discrepancies in uplift rates when applying a 1-D viscosity model tuned to fit the RSL data; these discrepancies cannot be reconciled by adding the realisations of lateral structure considered here. In many locations, the spread in model output for the eight different 3-D Earth models is of similar amplitude or larger than the influence of lateral structure (as defined by the average of all eight model runs). This reflects the differences between the four seismic and two lithosphere models used and implies a large uncertainty in defining the GIA signal given that other aspects that contribute to this uncertainty (e.g. scaling from seismic velocity to viscosity) were not considered in this study. In order to reduce this large model uncertainty, an important next step is to develop more accurate

  18. Cosmic ray modulation

    NASA Astrophysics Data System (ADS)

    Agarwal Mishra, Rekha; Mishra, Rajesh Kumar

    2016-07-01

    Propagation of cosmic rays to and inside the heliosphere, encounter an outward moving solar wind with cyclic magnetic field fluctuation and turbulence, causing convection and diffusion in the heliosphere. Cosmic ray counts from the ground ground-based neutron monitors at different cut of rigidity show intensity changes, which are anti-correlated with sunspot numbers. They also lose energy as they propagate towards the Earth and experience various types of modulations due to different solar activity indices. In this work, we study the first three harmonics of cosmic ray intensity on geo-magnetically quiet days over the period 1965-2014 for Beijing, Moscow and Tokyo neutron monitoring stations located at different cut off rigidity. The amplitude of first harmonic remains high for low cutoff rigidity as compared to high cutoff rigidity on quiet days. The diurnal amplitude significantly decreases during solar activity minimum years. The diurnal time of maximum significantly shifts to an earlier time as compared to the corotational direction having different cutoff rigidities. The time of maximum for first harmonic significantly shifts towards later hours and for second harmonic it shifts towards earlier hours at low cutoff rigidity station as compared to the high cut off rigidity station on quiet days. The amplitude of second/third harmonics shows a good positive correlation with solar wind velocity, while the others (i.e. amplitude and phase) have no significant correlation on quiet days. The amplitude and direction of the anisotropy on quiet days does not show any significant dependence on high-speed solar wind streams for these neutron monitoring stations of different cutoff rigidity threshold. Keywords: cosmic ray, cut off rigidity, quiet days, harmonics, amplitude, phase.

  19. Catching Cosmic Rays with a DSLR

    ERIC Educational Resources Information Center

    Sibbernsen, Kendra

    2010-01-01

    Cosmic rays are high-energy particles from outer space that continually strike the Earth's atmosphere and produce cascades of secondary particles, which reach the surface of the Earth, mainly in the form of muons. These particles can be detected with scintillator detectors, Geiger counters, cloud chambers, and also can be recorded with commonly…

  20. Multi-spectra Cosmic Ray Flux Measurement

    NASA Astrophysics Data System (ADS)

    He, Xiaochun; Dayananda, Mathes

    2010-02-01

    The Earth's upper atmosphere is constantly bombarded by rain of charged particles known as primary cosmic rays. These primary cosmic rays will collide with the atmospheric molecules and create extensive secondary particles which shower downward to the surface of the Earth. In recent years, a few studies have been done regarding to the applications of the cosmic ray measurements and the correlations between the Earth's climate conditions and the cosmic ray fluxes [1,2,3]. Most of the particles, which reach to the surface of the Earth, are muons together with a small percentage of electrons, gammas, neutrons, etc. At Georgia State University, multiple cosmic ray particle detectors have been constructed to measure the fluxes and energy distributions of the secondary cosmic ray particles. In this presentation, we will briefly describe these prototype detectors and show the preliminary test results. Reference: [1] K.Borozdin, G.Hogan, C.Morris, W.Priedhorsky, A.Saunders, L.Shultz, M.Teasdale, Nature, Vol.422, 277 (2003). [2] L.V. Egorova, V. Ya Vovk, O.A. Troshichev, Journal of Atmospheric and Terrestrial Physics 62, 955-966 (2000). [3] Henrik Svensmark, Phy. Rev. Lett. 81, 5027 (1998). )

  1. Cosmic Rays as a Factor of Biospheric Evolution

    NASA Astrophysics Data System (ADS)

    Miroshnichenko, L. I.

    2014-10-01

    There are no doubts that the Earth's space environment in the past inevitably has exerted direct and/or indirect influence [1-4] on the conditions of terrestrial life and biospheric evolution. Well-known space factors are usually the fluxes of cosmic dust and gas, comets and asteroids, cosmic rays (energetic particles of galactic and/or solar origin), interplanetary plasma (solar wind) and electromagnetic radiation of different energies, wave lengths, or frequencies. Of great interest are radiation conditions and their variations, especially in the remote past (over the geological time scales). The Sun, the most important and indispensable condition for the existence of the Earth's biosphere, is also a potential source of dangerous emissions. In continuation of (and in addition to) our review paper [3], below we summarize the observational data and results of theoretical works that have been carried out and/or published mainly after 2012. These studies are actually in the frontier region between the Astrobiology and Space Weather. Our main attention is paid to cosmic rays (CR) of galactic and solar origin (GCR and SCR, respectively).

  2. About the Influence of the initial Atmosphere on the Earth's Temperature Distribution during it's Accumulation

    NASA Astrophysics Data System (ADS)

    Khachay, Y.; Anfilogov, V.; Antipin, A.

    2012-04-01

    We suggested a new model for accumulation of planets of the Earth's group [1], which is based on the contemporary results of geochemical analyses, which allow to obtain the concentrations of short living radioactive isotopes of 26Al in the matter of the pre planet cloud [2]. With use of that data new estimations of temperature distribution into the growing planetary pre planetary bodies into the Earth's nebular zone had been obtained. For the further Earth's temperature evolution, as it had been showed by the results of numerical modeling, the main role belongs to the temperature distribution in the forming Earth's core and the existence of a dense and transparent atmosphere. The shadow influence of the initial atmosphere had been researched in the paper [3]. We shall give the main consideration to these problems in that paper. It had been shown in [1], that on the earliest accumulation stage the heat release by the decay of 26Al it is sufficient for forming a central melted area and solid relatively thin mainly silicate upper envelope in the pre planetary body, with dimensions, larger than (50-100) km. The impact velocities on that stage are yet not large, therefore by the bodies impact with these or near dimensions liquid and mainly iron their parts merge, but the masses of the pre planetary bodies are not sufficient to gravitational keeping of silicate parts of the cold solid envelope. On that stage they remain into the nebular zone of the proto planet and the mechanism of matter differentiation for the future core and mantle reservoirs realizes. The process takes place yet in small bodies and is in time to finish during less than 10 million years. The next forming of the core and mantle structure continues according to all known estimations about 100 million years. Because of the merging of inner liquid parts of impacting bodies occur due to inelastic impact, the main part of potential energy transforms into heat. That continues up to that time when the iron

  3. THE INFLUENCE OF PRESSURE-DEPENDENT VISCOSITY ON THE THERMAL EVOLUTION OF SUPER-EARTHS

    SciTech Connect

    Stamenkovic, Vlada; Noack, Lena; Spohn, Tilman

    2012-03-20

    We study the thermal evolution of super-Earths with a one-dimensional (1D) parameterized convection model that has been adopted to account for a strong pressure dependence of the viscosity. A comparison with a 2D spherical convection model shows that the derived parameterization satisfactorily represents the main characteristics of the thermal evolution of massive rocky planets. We find that the pressure dependence of the viscosity strongly influences the thermal evolution of super-Earths-resulting in a highly sluggish convection regime in the lower mantles of those planets. Depending on the effective activation volume and for cooler initial conditions, we observe with growing planetary massmore » even the formation of a conductive lid above the core-mantle boundary (CMB), a so-called CMB-lid. For initially molten planets our results suggest no CMB-lids but instead a hot lower mantle and core as well as sluggish lower mantle convection. This implies that the initial interior temperatures, especially in the lower mantle, become crucial for the thermal evolution-the thermostat effect suggested to regulate the interior temperatures in terrestrial planets does not work for massive planets if the viscosity is strongly pressure dependent. The sluggish convection and the potential formation of the CMB-lid reduce the convective vigor throughout the mantle, thereby affecting convective stresses, lithospheric thicknesses, and heat fluxes. The pressure dependence of the viscosity may therefore also strongly affect the propensity of plate tectonics, volcanic activity, and the generation of a magnetic field of super-Earths.« less

  4. Space Weather Observations by GNSS Radio Occultation: From FORMOSAT-3/COSMIC to FORMOSAT-7/COSMIC-2

    PubMed Central

    Yue, Xinan; Schreiner, William S; Pedatella, Nicholas; Anthes, Richard A; Mannucci, Anthony J; Straus, Paul R; Liu, Jann-Yenq

    2014-01-01

    The joint Taiwan-United States FORMOSAT-3/COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) mission, hereafter called COSMIC, is the first satellite constellation dedicated to remotely sense Earth's atmosphere and ionosphere using a technique called Global Positioning System (GPS) radio occultation (RO). The occultations yield abundant information about neutral atmospheric temperature and moisture as well as space weather estimates of slant total electron content, electron density profiles, and an amplitude scintillation index, S4. With the success of COSMIC, the United States and Taiwan are moving forward with a follow-on RO mission named FORMOSAT-7/COSMIC-2 (COSMIC-2), which will ultimately place 12 satellites in orbit with two launches in 2016 and 2019. COSMIC-2 satellites will carry an advanced Global Navigation Satellite System (GNSS) RO receiver that will track both GPS and Russian Global Navigation Satellite System signals, with capability for eventually tracking other GNSS signals from the Chinese BeiDou and European Galileo system, as well as secondary space weather payloads to measure low-latitude plasma drifts and scintillation at multiple frequencies. COSMIC-2 will provide 4–6 times (10–15X in the low latitudes) the number of atmospheric and ionospheric observations that were tracked with COSMIC and will also improve the quality of the observations. In this article we focus on COSMIC/COSMIC-2 measurements of key ionospheric parameters. PMID:26213514

  5. Space Weather Observations by GNSS Radio Occultation: From FORMOSAT-3/COSMIC to FORMOSAT-7/COSMIC-2.

    PubMed

    Yue, Xinan; Schreiner, William S; Pedatella, Nicholas; Anthes, Richard A; Mannucci, Anthony J; Straus, Paul R; Liu, Jann-Yenq

    2014-11-01

    The joint Taiwan-United States FORMOSAT-3/COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) mission, hereafter called COSMIC, is the first satellite constellation dedicated to remotely sense Earth's atmosphere and ionosphere using a technique called Global Positioning System (GPS) radio occultation (RO). The occultations yield abundant information about neutral atmospheric temperature and moisture as well as space weather estimates of slant total electron content, electron density profiles, and an amplitude scintillation index, S4. With the success of COSMIC, the United States and Taiwan are moving forward with a follow-on RO mission named FORMOSAT-7/COSMIC-2 (COSMIC-2), which will ultimately place 12 satellites in orbit with two launches in 2016 and 2019. COSMIC-2 satellites will carry an advanced Global Navigation Satellite System (GNSS) RO receiver that will track both GPS and Russian Global Navigation Satellite System signals, with capability for eventually tracking other GNSS signals from the Chinese BeiDou and European Galileo system, as well as secondary space weather payloads to measure low-latitude plasma drifts and scintillation at multiple frequencies. COSMIC-2 will provide 4-6 times (10-15X in the low latitudes) the number of atmospheric and ionospheric observations that were tracked with COSMIC and will also improve the quality of the observations. In this article we focus on COSMIC/COSMIC-2 measurements of key ionospheric parameters.

  6. Simulating cosmic radiation absorption and secondary particle production of solar panel layers of Low Earth Orbit (LEO) satellite with GEANT4

    NASA Astrophysics Data System (ADS)

    Yiǧitoǧlu, Merve; Veske, Doǧa; Nilüfer Öztürk, Zeynep; Bilge Demirköz, Melahat

    2016-07-01

    All devices which operate in space are exposed to cosmic rays during their operation. The resulting radiation may cause fatal damages in the solid structure of devices and the amount of absorbed radiation dose and secondary particle production for each component should be calculated carefully before the production. Solar panels are semiconductor solid state devices and are very sensitive to radiation. Even a short term power cut-off may yield a total failure of the satellite. Even little doses of radiation can change the characteristics of solar cells. This deviation can be caused by rarer high energetic particles as well as the total ionizing dose from the abundant low energy particles. In this study, solar panels planned for a specific LEO satellite, IMECE, are analyzed layer by layer. The Space Environment Information System (SPENVIS) database and GEANT4 simulation software are used to simulate the layers of the panels. The results obtained from the simulation will be taken in account to determine the amount of radiation protection and resistance needed for the panels or to revise the design of the panels.

  7. Earth's magnetic field as a radiator to detect cosmic ray electrons of energy greater than 10 to the 12th power eV

    NASA Technical Reports Server (NTRS)

    Stephens, S. A.; Balasubrahmanyan, V. K.

    1983-01-01

    The synchrotron emission by electrons of energy greater than a few TeV in Earth's magnetic field was examined. An omnidirectional detector, it is shown, can be satisfactorily used to estimate the energy. The collecting power of the detector, it is also shown, is a sensitive function of the area of the detector, the energy of electron, and the number of photons required to identify an electron. The event rate expected was calculated using an ideal balloon-borne detector.

  8. Cosmic Catastrophes

    NASA Astrophysics Data System (ADS)

    Wheeler, J. Craig

    2000-07-01

    In this tour de force of the ultimate and extreme in astrophysics, renowned astrophysicist and author J. Craig Wheeler takes us on a breathtaking journey to supernovae, black holes, gamma-ray bursts and adventures in hyperspace. This is no far-fetched science fiction tale, but an enthusiastic exploration of ideas at the cutting edge of current astrophysics. Wheeler follows the tortuous life of a star from birth to evolution and death, and goes on to consider the complete collapse of a star into a black hole, worm-hole time machines, the possible birth of baby bubble universes, and the prospect of a revolutionary view of space and time in a ten-dimensional string theory. Along the way he offers evidence that suggests the Universe is accelerating and describes recent developments in understanding gamma-ray bursts--perhaps the most catastrophic cosmic events of all. With the use of lucid analogies, simple language and crystal-clear cartoons, Cosmic Catastrophes makes accessible some of the most exciting and mind-bending objects and ideas in the Universe. J. Craig Wheeler is currently Samuel T. and Fern Yanagisawa Regents Professor of Astronomy at the University of Texas at Austin and Vice President of the American Astronomical Society as of 1999.

  9. Cosmic strings and superconducting cosmic strings

    NASA Technical Reports Server (NTRS)

    Copeland, Edmund

    1988-01-01

    The possible consequences of forming cosmic strings and superconducting cosmic strings in the early universe are discussed. Lecture 1 describes the group theoretic reasons for and the field theoretic reasons why cosmic strings can form in spontaneously broken gauge theories. Lecture 2 discusses the accretion of matter onto string loops, emphasizing the scenario with a cold dark matter dominated universe. In lecture 3 superconducting cosmic strings are discussed, as is a mechanism which leads to the formation of structure from such strings.

  10. Research in cosmic and gamma ray astrophysics

    NASA Technical Reports Server (NTRS)

    Stone, E. C.; Davis, L., Jr.; Mewaldt, R. A.; Prince, T. A.

    1989-01-01

    Research activities in cosmic rays, gamma rays, and astrophysical plasmas are covered. The activities are divided into sections and described, followed by a bibliography. The astrophysical aspects of cosmic rays, gamma rays, and of the radiation and electromagnetic field environment of the Earth and other planets are investigated. These investigations are performed by means of energetic particle and photon detector systems flown on spacecraft and balloons.

  11. Galaxies in Filaments have More Satellites: The Influence of the Cosmic Web on the Satellite Luminosity Function in the SDSS

    NASA Astrophysics Data System (ADS)

    Guo, Quan; Tempel, E.; Libeskind, N. I.

    2015-02-01

    We investigate whether the satellite luminosity function (LF) of primary galaxies identified in the Sloan Digital Sky Survey (SDSS) depends on whether the host galaxy is in a filament or not. Isolated primary galaxies are identified in the SDSS spectroscopic sample, and potential satellites (that are up to four magnitudes fainter than their hosts) are searched for in the much deeper photometric sample. Filaments are constructed from the galaxy distribution by the Bisous process. Isolated primary galaxies are divided into two subsamples: those in filaments and those not in filaments. We examine the stacked mean satellite LF of both the filament and nonfilament samples and find that, on average, the satellite LF of galaxies in filaments is significantly higher than those of galaxies not in filaments. The filamentary environment can increase the abundance of the brightest satellites (M sat. < M prim. + 2.0) by a factor of ~2 compared with nonfilament isolated galaxies. This result is independent of the primary galaxy magnitude, although the satellite LF of galaxies in the faintest magnitude bin is too noisy to determine if such a dependence exists. Because our filaments are extracted from a spectroscopic flux-limited sample, we consider the possibility that the difference in satellite LF is due to a redshift, color, or environmental bias, finding these to be insufficient to explain our result. The dependence of the satellite LF on the cosmic web suggests that the filamentary environment may have a strong effect on the efficiency of galaxy formation.

  12. REVIEWS OF TOPICAL PROBLEMS: Astrophysical aspects of cosmic-ray research (first 75 years and outlook for the future)

    NASA Astrophysics Data System (ADS)

    Ginzburg, Vitalii L.

    1988-06-01

    (Invited talk at the 20th International Cosmic Ray Conference, Moscow, 2-15 August 1987) The basic topics discussed here are the primary cosmic rays near the earth, cosmic rays in the universe, the origin of cosmic rays, a galactic model with a halo, and some prospects for future research.

  13. Composition of LHB Comets and Their Influence on the Early Earth Atmosphere Composition

    NASA Technical Reports Server (NTRS)

    Tornow, C.; Kupper, S.; Ilgner, M.; Kuehrt, E.; Motschmann, U.

    2011-01-01

    Two main processes were responsible for the composition of this atmosphere: chemical evolution of the volatile fraction of the accretion material forming the planet and the delivery of gasses to the planetary surface by impactors during the late heavy bombardment (LHB). The amount and composition of the volatile fraction influences the outgassing of the Earth mantle during the last planetary formation period. A very weakened form of outgassing activity can still be observed today by examining the composition of volcanic gasses. An enlightenment of the second process is based on the sparse records of the LHB impactors resulting from the composition of meteorites, observed cometary comas, and the impact material found on the Moon. However, for an assessment of the influence of the outgassing on the one hand and the LHB event on the other, one has to supplement the observations with numerical simulations of the formation of volatiles and their incorporation into the accretion material which is the precursors of planetary matter, comets and asteroids. These simulations are performed with a combined hydrodynamic-chemical model of the solar nebula (SN). We calculate the chemical composition of the gas and dust phase of the SN. From these data, we draw conclusions on the upper limits of the water content and the amount of carbon and nitrogen rich volatiles incorporated later into the accretion material. Knowing these limits we determine the portion of major gas compounds delivered during the LHB and compare it with the related quantities of the outgassed species.

  14. Atmospheric influences on infrared-laser signals used for occultation measurements between Low Earth Orbit satellites

    NASA Astrophysics Data System (ADS)

    Schweitzer, S.; Kirchengast, G.; Proschek, V.

    2011-10-01

    LEO-LEO infrared-laser occultation (LIO) is a new occultation technique between Low Earth Orbit (LEO) satellites, which applies signals in the short wave infrared spectral range (SWIR) within 2 μm to 2.5 μm. It is part of the LEO-LEO microwave and infrared-laser occultation (LMIO) method that enables to retrieve thermodynamic profiles (pressure, temperature, humidity) and altitude levels from microwave signals and profiles of greenhouse gases and further variables such as line-of-sight wind speed from simultaneously measured LIO signals. Due to the novelty of the LMIO method, detailed knowledge of atmospheric influences on LIO signals and of their suitability for accurate trace species retrieval did not yet exist. Here we discuss these influences, assessing effects from refraction, trace species absorption, aerosol extinction and Rayleigh scattering in detail, and addressing clouds, turbulence, wind, scattered solar radiation and terrestrial thermal radiation as well. We show that the influence of refractive defocusing, foreign species absorption, aerosols and turbulence is observable, but can be rendered small to negligible by use of the differential transmission principle with a close frequency spacing of LIO absorption and reference signals within 0.5%. The influences of Rayleigh scattering and terrestrial thermal radiation are found negligible. Cloud-scattered solar radiation can be observable under bright-day conditions, but this influence can be made negligible by a close time spacing (within 5 ms) of interleaved laser-pulse and background signals. Cloud extinction loss generally blocks SWIR signals, except very thin or sub-visible cirrus clouds, which can be addressed by retrieving a cloud layering profile and exploiting it in the trace species retrieval. Wind can have a small influence on the trace species absorption, which can be made negligible by using a simultaneously retrieved or a moderately accurate background wind speed profile. We conclude that

  15. GALAXIES IN FILAMENTS HAVE MORE SATELLITES: THE INFLUENCE OF THE COSMIC WEB ON THE SATELLITE LUMINOSITY FUNCTION IN THE SDSS

    SciTech Connect

    Guo, Quan; Libeskind, N. I.; Tempel, E., E-mail: qguo@aip.de

    We investigate whether the satellite luminosity function (LF) of primary galaxies identified in the Sloan Digital Sky Survey (SDSS) depends on whether the host galaxy is in a filament or not. Isolated primary galaxies are identified in the SDSS spectroscopic sample, and potential satellites (that are up to four magnitudes fainter than their hosts) are searched for in the much deeper photometric sample. Filaments are constructed from the galaxy distribution by the Bisous process. Isolated primary galaxies are divided into two subsamples: those in filaments and those not in filaments. We examine the stacked mean satellite LF of both themore » filament and nonfilament samples and find that, on average, the satellite LF of galaxies in filaments is significantly higher than those of galaxies not in filaments. The filamentary environment can increase the abundance of the brightest satellites (M {sub sat.} < M {sub prim.} + 2.0) by a factor of ∼2 compared with nonfilament isolated galaxies. This result is independent of the primary galaxy magnitude, although the satellite LF of galaxies in the faintest magnitude bin is too noisy to determine if such a dependence exists. Because our filaments are extracted from a spectroscopic flux-limited sample, we consider the possibility that the difference in satellite LF is due to a redshift, color, or environmental bias, finding these to be insufficient to explain our result. The dependence of the satellite LF on the cosmic web suggests that the filamentary environment may have a strong effect on the efficiency of galaxy formation.« less

  16. Caught in the Solar Wind: A Study of Space Weather and its Influence on Earth

    NASA Astrophysics Data System (ADS)

    Hill, R.; Chuckran, A.; Erickson, P. J.

    2007-12-01

    Space weather is a phenomenon that is becoming more familiar to the general public. As people are increasingly reliant on 21st century technology, the potential for disruption to their daily lives also rises. As the sun approaches its next solar maximum in 2011 or 2012, the peak of Cycle 24 is expected to be the highest of the satellite age, perhaps surpassing that of Cycle 19 in 1957-58. In this teaching unit, we have attempted to create a series of lessons that sheds light on the concept of space weather and the sun's influences on earth's magnetic field and upper atmosphere. Within this unit, we have provided ample opportunities for students to access and interpret real scientific data from a variety of sources. The main location is the web site www.spaceweather.com , which has near real time data from satellites such as SOHO, STEREO, ACE and POES. This data is easily viewed and explained within the site, and with appropriate instruction, students can regularly gather data, make predictions, and draw conclusions based on the current behavior of the sun. Examples include sunspot number and development, speed and density of solar wind, orientation and strength of the interplanetary magnetic field, location of coronal holes, planetary K index and X-ray solar flares. Depending on the level of the students, some or all of this data can be compiled over a period of time to better understand the behavior of the sun as well as its influence on Earth. The goal of this unit is to provide a vehicle for students to understand how data is used by scientists. Once they have the base knowledge, students may be able to construct their own questions and follow through with research. An inquiry-based approach is incorporated whenever possible. With the onset of a potentially active solar cycle in the near future, teachers have the opportunity to make a dramatic connection between the natural world and their daily lives. Solar storms can cause disruption to telephone communication

  17. Cosmic Discovery

    NASA Astrophysics Data System (ADS)

    Harwit, Martin

    1984-04-01

    In the remarkable opening section of this book, a well-known Cornell astronomer gives precise thumbnail histories of the 43 basic cosmic discoveries - stars, planets, novae, pulsars, comets, gamma-ray bursts, and the like - that form the core of our knowledge of the universe. Many of them, he points out, were made accidentally and outside the mainstream of astronomical research and funding. This observation leads him to speculate on how many more major phenomena there might be and how they might be most effectively sought out in afield now dominated by large instruments and complex investigative modes and observational conditions. The book also examines discovery in terms of its political, financial, and sociological context - the role of new technologies and of industry and the military in revealing new knowledge; and methods of funding, of peer review, and of allotting time on our largest telescopes. It concludes with specific recommendations for organizing astronomy in ways that will best lead to the discovery of the many - at least sixty - phenomena that Harwit estimates are still waiting to be found.

  18. Cosmic ray modulation by high-speed solar wind fluxes

    NASA Technical Reports Server (NTRS)

    Dorman, L. I.; Kaminer, N. S.; Kuzmicheva, A. E.; Mymrina, N. V.

    1985-01-01

    Cosmic ray intensity variations connected with recurrent high-speed fluxes (HSF) of solar wind are investigated. The increase of intensity before the Earth gets into a HSF, north-south anisotropy and diurnal variation of cosmic rays inside a HSF as well as the characteristics of Forbush decreases are considered.

  19. Radiative transfer in the earth's atmosphere and ocean: influence of ocean waves.

    PubMed

    Plass, G N; Kattawar, G W; Guinn, J A

    1975-08-01

    The radiance in the earth's atmosphere and ocean is calculated for a realistic model including an ocean surface with waves. Individual photons are followed in a Monte Carlo calculation. In the atmosphere, both Rayleigh scattering by the molecules and Mie scattering by the aerosols as well as molecular and aerosol absorption are taken into account. Similarly, in the ocean, both Rayleigh scattering by the water molecules and Mie scattering by the hydrosols as well as absorption by the water molecules and hydrosols are considered. Separate single-scattering functions are used which are calculated separately for the aerosols and the hydrosols from the Mie theory with appropriate and different size distributions in each case. The scattering angles are determined from the appropriate scattering function including the strong forwardscattering peak when there is aerosol or hydrosol scattering. Both the reflected and refracted rays, as well as the rays that undergo total internal reflection, are followed at the oceanc surface. The wave slope is chosen from the Cox-Munk distribution. Graphs show the influence of the waves on the upward radiance at the top of the atmosphere and just above the ocean surface and on the downward radiance just below the ocean surface as well as deeper within the ocean. The radiance changes are sufficient at the top of the atmosphere to determine the sea state from satellite measurements. Within the ocean the waves smooth out the abrupt transition that occurs at the edge of the allowed cone for radiation entering a calm ocean. The influence of the waves on the contrast between the sky and sea at the horizon is discussed. It is shown that the downward flux just below the surface increases with wind speed at all solar angles.

  20. Influence of magnetic field configuration on magnetohydrodynamic waves in Earth's core

    NASA Astrophysics Data System (ADS)

    Knezek, Nicholas; Buffett, Bruce

    2018-04-01

    We develop a numerical model to study magnetohydrodynamic waves in a thin layer of stratified fluid near the surface of Earth's core. Past studies have been limited to using simple background magnetic field configurations. However, the choice of field distribution can dramatically affect the structure and frequency of the waves. To permit a more general treatment of background magnetic field and layer stratification, we combine finite volume and Fourier methods to describe the wave motions. We validate our model by comparisons to previous studies and examine the influence of background magnetic field configuration on two types of magnetohydrodynamic waves. We show that the structure of zonal Magnetic-Archimedes-Coriolis (MAC) waves for a dipole background field is unstable to small perturbations of the field strength in the equatorial region. Modifications to the wave structures are computed for a range of field configurations. In addition, we show that non-zonal MAC waves are trapped near the equator for realistic magnetic field distributions, and that their latitudinal extent depends upon the distribution of magnetic field strength at the CMB.

  1. Mobility of rare earth elements in mine drainage: Influence of iron oxides, carbonates, and phosphates.

    PubMed

    Edahbi, Mohamed; Plante, Benoît; Benzaazoua, Mostafa; Ward, Matthew; Pelletier, Mia

    2018-05-01

    The geochemical behavior of rare earth elements (REE) was investigated using weathering cells. The influence of sorption and precipitation on dissolved REE mobility and fractionation is evaluated using synthetic iron-oxides, carbonates, and phosphates. Sorption cell tests are conducted on the main lithologies of the expected waste rocks from the Montviel deposit. The sorbed materials are characterized using a scanning electron microscope (SEM) equipped with a microanalysis system (energy dispersive spectroscopy EDS) (SEM-EDS), X-ray diffraction (XRD), and X-ray absorption near edge structure (XANES) in order to understand the effect of the synthetic minerals on REE mobility. The results confirm that sorption and precipitation control the mobility and fractionation of REE. The main sorbent phases are the carbonates, phosphates (present as accessory minerals in the Montviel waste rocks), and iron oxides (main secondary minerals generated upon weathering of the Montviel lithologies). The XANES results show that REE are present as trivalent species after weathering. Thermodynamic equilibrium calculations results using Visual Minteq suggest that REE could precipitate as secondary phosphates (REEPO 4 ). Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. The Influence of Heat Flux Boundary Heterogeneity on Heat Transport in Earth's Core

    NASA Astrophysics Data System (ADS)

    Davies, C. J.; Mound, J. E.

    2017-12-01

    Rotating convection in planetary systems can be subjected to large lateral variations in heat flux from above; for example, due to the interaction between the metallic cores of terrestrial planets and their overlying silicate mantles. The boundary anomalies can significantly reorganise the pattern of convection and influence global diagnostics such as the Nusselt number. We have conducted a suite of numerical simulations of rotating convection in a spherical shell geometry comparing convection with homogeneous boundary conditions to that with two patterns of heat flux variation at the outer boundary: one hemispheric pattern, and one derived from seismic tomographic imaging of Earth's lower mantle. We consider Ekman numbers down to 10-6 and flux-based Rayleigh numbers up to 800 times critical. The heterogeneous boundary conditions tend to increase the Nusselt number relative to the equivalent homogeneous case by altering both the flow and temperature fields, particularly near the top of the convecting region. The enhancement in Nusselt number tends to increase as the amplitude and wavelength of the boundary heterogeneity is increased and as the system becomes more supercritical. In our suite of models, the increase in Nusselt number can be as large as 25%. The slope of the Nusselt-Rayleigh scaling also changes when boundary heterogeneity is included, which has implications when extrapolating to planetary conditions. Additionally, regions of effective thermal stratification can develop when strongly heterogeneous heat flux conditions are applied at the outer boundary.

  3. Influence of Ice Cloud Microphysics on Imager-Based Estimates of Earth's Radiation Budget

    NASA Astrophysics Data System (ADS)

    Loeb, N. G.; Kato, S.; Minnis, P.; Yang, P.; Sun-Mack, S.; Rose, F. G.; Hong, G.; Ham, S. H.

    2016-12-01

    A central objective of the Clouds and the Earth's Radiant Energy System (CERES) is to produce a long-term global climate data record of Earth's radiation budget from the TOA down to the surface along with the associated atmospheric and surface properties that influence it. CERES relies on a number of data sources, including broadband radiometers measuring incoming and reflected solar radiation and OLR, high-resolution spectral imagers, meteorological, aerosol and ozone assimilation data, and snow/sea-ice maps based on microwave radiometer data. While the TOA radiation budget is largely determined directly from accurate broadband radiometer measurements, the surface radiation budget is derived indirectly through radiative transfer model calculations initialized using imager-based cloud and aerosol retrievals and meteorological assimilation data. Because ice cloud particles exhibit a wide range of shapes, sizes and habits that cannot be independently retrieved a priori from passive visible/infrared imager measurements, assumptions about the scattering properties of ice clouds are necessary in order to retrieve ice cloud optical properties (e.g., optical depth) from imager radiances and to compute broadband radiative fluxes. This presentation will examine how the choice of an ice cloud particle model impacts computed shortwave (SW) radiative fluxes at the top-of-atmosphere (TOA) and surface. The ice cloud particle models considered correspond to those from prior, current and future CERES data product versions. During the CERES Edition2 (and Edition3) processing, ice cloud particles were assumed to be smooth hexagonal columns. In the Edition4, roughened hexagonal columns are assumed. The CERES team is now working on implementing in a future version an ice cloud particle model comprised of a two-habit ice cloud model consisting of roughened hexagonal columns and aggregates of roughened columnar elements. In each case, we use the same ice particle model in both the

  4. FUPSOL: Modelling the Future and Past Solar Influence on Earth Climate

    NASA Astrophysics Data System (ADS)

    Anet, J. G.; Rozanov, E.; Peter, T.

    2012-04-01

    Global warming is becoming one of the main threats to mankind. There is growing evidence that anthropogenic greenhouse gases have become the dominant factor since about 1970. At the same time natural factors of climate change such as solar and volcanic forcings cannot be neglected on longer time scales. Despite growing scientific efforts over the last decades in both, observations and simulations, the uncertainty of the solar contribution to the past climate change remained unacceptably high (IPCC, 2007), the reasons being on one hand missing observations of solar irradiance prior to the satellite era, and on the other hand a majority of models so far not including all processes relevant for solar-climate interactions. This project aims at elucidating the processes governing the effects of solar activity variations on Earth's climate. We use the state-of-the-art coupled atmosphere-ocean-chemistry-climate model (AOCCM) SOCOL (Schraner et al, 2008) developed in Switzerland by coupling the community Earth System Model (ESM) COSMOS distributed by MPI for Meteorology (Hamburg, Germany) with a comprehensive atmospheric chemistry module. The model solves an extensive set of equations describing the dynamics of the atmosphere and ocean, radiative transfer, transport of species, their chemical transformations, cloud formation and the hydrological cycle. The intention is to show how past solar variations affected climate and how the decrease in solar forcing expected for the next decades will affect climate on global and regional scales. We will simulate the global climate system behavior during Dalton minimum (1790 and 1830) and first half of 21st century with a series of multiyear ensemble experiments and perform these experiments using all known anthropogenic and natural climate forcing taken in different combinations to understand the effects of solar irradiance in different spectral regions and particle precipitation variability. Further on, we will quantify the solar

  5. Against the Grain: The Influence of Changing Agricultural Management on the Earth System

    NASA Astrophysics Data System (ADS)

    Foley, J. A.

    2007-12-01

    The rise of modern agriculture was one of the most transformative events in human history, and has forever changed our relationship to the natural world. By clearing tropical forests, practicing subsistence agriculture on marginal lands and intensifying industrialized farmland production, agricultural practices are changing the worldês landscapes in pervasive ways. In the past decade, we have made tremendous progress in monitoring agricultural expansion from satellites, and modeling associated environmental impacts. In the past decade, the Earth System Science research community has begun to recognize the importance of agricultural lands, particularly as they continue expanding at the expense of important natural ecosystems, potentially altering the planetês carbon cycle and climate. With the advent of new remote sensing and global modeling methods, several efforts have documented the expansion of agricultural lands, the corresponding loss of natural ecosystems, and how this may influence the earth system. But the geographic expansion of agricultural lands is not the whole story. While significant agricultural expansion (or extensification) has occurred in the past few decades, the intensification of agricultural practices Ð under the aegis of the -Green Revolution" Ð has dramatically altered the relationship between humans and environmental systems across the world. Simply put, many of the worldês existing agricultural lands are being used much more intensively as opportunities for agricultural expansion are being exhausted elsewhere. In the last 40 years, global agricultural production has more than doubled Ð although global cropland has increased by only 12% Ð mainly through the use of high yielding varieties of grain, increased reliance on irrigation, massive increases in chemical fertilization, and increased mechanization. Indeed, in the past 40 years there has been a 700% increase in global fertilizer use and a 70% increase in irrigated cropland area

  6. Lightning Discharges, Cosmic Rays and Climate

    NASA Astrophysics Data System (ADS)

    Kumar, Sanjay; Siingh, Devendraa; Singh, R. P.; Singh, A. K.; Kamra, A. K.

    2018-03-01

    The entirety of the Earth's climate system is continuously bombarded by cosmic rays and exhibits about 2000 thunderstorms active at any time of the day all over the globe. Any linkage among these vast systems should have global consequences. Numerous studies done in the past deal with partial links between some selected aspects of this grand linkage. Results of these studies vary from weakly to strongly significant and are not yet complete enough to justify the physical mechanism proposed to explain such links. This review is aimed at presenting the current understanding, based on the past studies on the link between cosmic ray, lightning and climate. The deficiencies in some proposed links are pointed out. Impacts of cosmic rays on engineering systems and the possible effects of cosmic rays on human health are also briefly discussed. Also enumerated are some problems for future work which may help in developing the grand linkage among these three vast systems.

  7. Anisotropy and corotation of galactic cosmic rays.

    PubMed

    Amenomori, M; Ayabe, S; Bi, X J; Chen, D; Cui, S W; Danzengluobu; Ding, L K; Ding, X H; Feng, C F; Feng, Zhaoyang; Feng, Z Y; Gao, X Y; Geng, Q X; Guo, H W; He, H H; He, M; Hibino, K; Hotta, N; Hu, Haibing; Hu, H B; Huang, J; Huang, Q; Jia, H Y; Kajino, F; Kasahara, K; Katayose, Y; Kato, C; Kawata, K; Labaciren; Le, G M; Li, A F; Li, J Y; Lou, Y-Q; Lu, H; Lu, S L; Meng, X R; Mizutani, K; Mu, J; Munakata, K; Nagai, A; Nanjo, H; Nishizawa, M; Ohnishi, M; Ohta, I; Onuma, H; Ouchi, T; Ozawa, S; Ren, J R; Saito, T; Saito, T Y; Sakata, M; Sako, T K; Sasaki, T; Shibata, M; Shiomi, A; Shirai, T; Sugimoto, H; Takita, M; Tan, Y H; Tateyama, N; Torii, S; Tsuchiya, H; Udo, S; Wang, B; Wang, H; Wang, X; Wang, Y G; Wu, H R; Xue, L; Yamamoto, Y; Yan, C T; Yang, X C; Yasue, S; Ye, Z H; Yu, G C; Yuan, A F; Yuda, T; Zhang, H M; Zhang, J L; Zhang, N J; Zhang, X Y; Zhang, Y; Zhang, Yi; Zhaxisangzhu; Zhou, X X

    2006-10-20

    The intensity of Galactic cosmic rays is nearly isotropic because of the influence of magnetic fields in the Milky Way. Here, we present two-dimensional high-precision anisotropy measurement for energies from a few to several hundred teraelectronvolts (TeV), using the large data sample of the Tibet Air Shower Arrays. Besides revealing finer details of the known anisotropies, a new component of Galactic cosmic ray anisotropy in sidereal time is uncovered around the Cygnus region direction. For cosmic-ray energies up to a few hundred TeV, all components of anisotropies fade away, showing a corotation of Galactic cosmic rays with the local Galactic magnetic environment. These results have broad implications for a comprehensive understanding of cosmic rays, supernovae, magnetic fields, and heliospheric and Galactic dynamic environments.

  8. Cosmic physics data analysis program

    NASA Technical Reports Server (NTRS)

    Wilkes, R. Jeffrey

    1993-01-01

    A data analysis program was carried out to investigate the intensity, propagation, and origin of primary Cosmic Ray Galactic electrons. Scanning was carried out on two new balloon flight experiments as well as the border area of previous experiments. The identification and evaluation of the energies of the primary electrons were carried out. A new analysis of these data were incorporated into an overall evaluation of the roll of electrons in the problem of the origin of cosmic rays. Recent measurements indicate that the earth may be within the expanding Geminga supernova shock wave which is expected to have a major effect upon the propagation and the energy spectrum of galactic electrons. Calculations with the Geminga model indicate that the cut-off energy may be very close to the observed highest energy electrons in our analysis.

  9. Organic Matter in Cosmic Dust

    PubMed Central

    Sandford, Scott A.; Engrand, Cecile; Rotundi, Alessandra

    2018-01-01

    Organics are observed to be a significant component of cosmic dust in nearly all environments were dust is observed. In many cases only remote telescope observations of these materials are obtainable and our knowledge of the nature of these materials is very basic. However, it is possible to obtain actual samples of extraterrestrial dust in the Earth’s stratosphere, in Antarctic ice and snow, in near-Earth orbit, and via spacecraft missions to asteroids and comets. It is clear that cosmic dust contains a diverse population of organic materials that owe their origins to a variety of chemical processes occurring in many different environments. The presence of isotopic enrichments of D and 15N suggests that many of these organic materials have an interstellar/protosolar heritage. The study of these samples is of considerable importance since they are the best preserved materials of the early Solar System available. PMID:29422977

  10. GNSS Radio Occultation Observations as a data source for Ionospheric Assimilation: COSMIC-1 & COSMIC-2

    NASA Astrophysics Data System (ADS)

    Yue, X.; Schreiner, W. S.; Kuo, Y. H.

    2014-12-01

    Since the pioneer GPS/MET mission, low Earth orbit (LEO) based global navigation satellite system (GNSS) Radio Occultation (RO) technique has been a powerful technique in ionosphere monitoring. After that, many LEO satellites were launched with RO payload, include: CHAMP , GRACE, SAC-C/D, COSMIC, C/NOFS, Metop-A/B, TerraSAR-X/TanDEM-X, and etc. COSMIC was the first constellation of satellites dedicated primarily to RO and delivering RO data in near real time. Currently in UCAR CDAAC, we process most of these missions' RO data for the community. Due to the success of COSMIC mission, a follow on mission called COSMIC-2 will be launched in 2016 and 2018, respectively. The COSMIC-2 RO data will be 4-6 times of COSMIC due to the doubled satellite and GNSS signals. In this paper we will describe: (1) Data process and quality in UCAR/CDAAC; (2) Ionospheric data assimilation results based on COSMIC data; (3) OSSE study for COSMIC-2.

  11. COSMIC program documentation experience

    NASA Technical Reports Server (NTRS)

    Kalar, M. C.

    1970-01-01

    A brief history of COSMIC as it relates to the handling of program documentation is summarized; the items that are essential for computer program documentation are also discussed. COSMIC documentation and program standards handbook is appended.

  12. Cosmic Interactions

    NASA Astrophysics Data System (ADS)

    2008-01-01

    An image based on data taken with ESO's Very Large Telescope reveals a triplet of galaxies intertwined in a cosmic dance. ESO PR Photo 02/08 ESO PR Photo 02/08 NGC 7173, 7174, and 7176 The three galaxies, catalogued as NGC 7173 (top), 7174 (bottom right) and 7176 (bottom left), are located 106 million light-years away towards the constellation of Piscis Austrinus (the 'Southern Fish'). NGC 7173 and 7176 are elliptical galaxies, while NGC 7174 is a spiral galaxy with quite disturbed dust lanes and a long, twisted tail. This seems to indicate that the two bottom galaxies - whose combined shape bears some resemblance to that of a sleeping baby - are currently interacting, with NGC 7176 providing fresh material to NGC 7174. Matter present in great quantity around the triplet's members also points to the fact that NGC 7176 and NGC 7173 have interacted in the past. Astronomers have suggested that the three galaxies will finally merge into a giant 'island universe', tens to hundreds of times as massive as our own Milky Way. ESO PR Photo 02/08 ESO PR Photo 02b/08 NGC 7173, 7174, and 7176 The triplet is part of a so-called 'Compact Group', as compiled by Canadian astronomer Paul Hickson in the early 1980s. The group, which is the 90th entry in the catalogue and is therefore known as HCG 90, actually contains four major members. One of them - NGC 7192 - lies above the trio, outside of this image, and is another peculiar spiral galaxy. Compact groups are small, relatively isolated, systems of typically four to ten galaxies in close proximity to one another. Another striking example is Robert's Quartet. Compact groups are excellent laboratories for the study of galaxy interactions and their effects, in particular the formation of stars. As the striking image reveals, there are many other galaxies in the field. Some are distant ones, while others seem to be part of the family. Studies made with other telescopes have indeed revealed that the HCG 90 group contains 16 members

  13. Rare earth elements in coastal sediments of the northern Galician shelf: Influence of geological features

    NASA Astrophysics Data System (ADS)

    Prego, Ricardo; Caetano, Miguel; Bernárdez, Patricia; Brito, Pedro; Ospina-Alvarez, Natalia; Vale, Carlos

    2012-03-01

    The Northern coast of Galicia, NW Iberian Peninsula, exhibits a variety of geological features: Ortegal allochthonous complex, Ollo-de-Sapo autochthonous domain and massifs of Bares, Barqueiro and San-Ciprian. In order to examine the influence of terrestrial lithologies on coastal sediments, 103 samples were collected in the Rias of Ortigueira, Barqueiro and Viveiro, their neighbouring shelf and the estuaries of Mera, Sor and Landro rivers. Aluminium, Fe, Sc, particulate inorganic and organic carbon and rare earth elements (REE) were determined in the <2 mm fraction. In addition, calcite, muscovite, quartz and riebeckite minerals were identified and quantified in 33 selected samples. The distributions of riebeckite and Fe reflect the influence of Ortegal complex on the coastal areas around the Cape Ortegal. The highest concentrations of ΣREE were found in fine sediments from confined inner parts of the Rias (up to 233 mg kg-1), while most of the sands contained 11-70 mg kg-1. ΣREE normalised to European Shale (ES) highlights the relative abundance of lanthanides (ΣREEN>6) near Cape Ortegal and the innermost ria zones. The ratio between light and heavy REE (L/H) showed lower values (4-11) around Cape Ortegal and the shelf while higher ratios (15-23) were detected in west of the Cape Estaca-de-Bares and in the inner Viveiro Ria due to elevated contributions of La and Ce. The L/H values normalised to ES reflects the importance of HREE in the adjacent area to Ortegal Complex (LN/HN<0.8) and the LREE (LN/HN>1.4) in the inner estuaries and west Cape Estaca-de-Bares. The highest REE individual ES normalised were measured in fine-grained sediments of the Mera and Sor estuaries. Sediments from the eastern shelf of Cape Ortegal presented enhanced ratios only for HREE. These results indicate that distribution of REE in the northern Galician region is highly depending on the neighbouring lithological pattern, contrasting with the situation found in the western Galician

  14. Cosmic void clumps

    NASA Astrophysics Data System (ADS)

    Lares, M.; Luparello, H. E.; Garcia Lambas, D.; Ruiz, A. N.; Ceccarelli, L.; Paz, D.

    2017-10-01

    Cosmic voids are of great interest given their relation to the large scale distribution of mass and the way they trace cosmic flows shaping the cosmic web. Here we show that the distribution of voids has, in consonance with the distribution of mass, a characteristic scale at which void pairs are preferentially located. We identify clumps of voids with similar environments and use them to define second order underdensities. Also, we characterize its properties and analyze its impact on the cosmic microwave background.

  15. Cosmic ray experimental observations

    NASA Technical Reports Server (NTRS)

    Balasubrahmanyan, V. K.; Mcdonald, F. B.

    1974-01-01

    The current experimental situation in cosmic ray studies is discussed, with special emphasis on the development of new detector systems. Topics covered are the techniques for particle identification, energy measurements, gas Cerenkov counters, magnet spectrometers, ionization spectrometers, track detectors, nuclear emulsions, multiparameter analysis using arrays of detectors, the Goddard ionization spectrometer, charge spectra, relative abundances, isotope composition, antinuclei in cosmic rays, electrons, the measurement of cosmic ray arrival directions, and the prehistory of cosmic rays.

  16. The influence of the earth radiation on space target detection system

    NASA Astrophysics Data System (ADS)

    Su, Xiaofeng; Chen, FanSheng; Cuikun, .; Liuyan, .

    2017-05-01

    In the view of space remote sensing such as satellite detection space debris detection etc. visible band is usually used in order to have the all-weather detection capability, long wavelength infrared (LWIR) detection is also an important supplement. However, in the tow wave band, the earth can be a very strong interference source, especially in the dim target detecting. When the target is close to the earth, especially the LEO target, the background radiation of the earth will also enter into the baffle, and became the stray light through reflection, the stray light can reduce the signal to clutter ratio (SCR) of the target and make it difficult to be detected. In the visible band, the solar albedo by the earth is the main clutter source while in the LWIR band the radiation of the earth is the main clutter source. So, in this paper, we establish the energy transformation from the earth background radiation to the detection system to assess the effects of the stray light. Firstly, we discretize the surface of the earth to different unit, and using MODTRAN to calculate the radiation of the discrete point in different light and climate conditions, then, we integral all the radiation which can reach the baffle in the same observation angles to get the energy distribution, finally, according the target energy and the non-uniformity of the detector, we can calculate the design requirement of the system stray light suppression, which provides the design basis for the optical system.

  17. Cosmic Dust Catalog

    NASA Astrophysics Data System (ADS)

    Warren, J.; Watts, L.; Thomas-Keprta, K.; Wentworth, S.; Dodson, A.; Zolensky, Michael E.

    1997-07-01

    Since May 1981, the National Aeronautics and Space Administration (NASA) has used aircraft to collect cosmic dust (CD) particles from Earth's stratosphere. Specially designed dust collectors are prepared for flight and processed after flight in an ultraclean (Class-100) laboratory constructed for this purpose at the Lyndon B. Johnson Space Center (JSC) in Houston, Texas. Particles are individually retrieved from the collectors, examined and cataloged, and then made available to the scientific community for research. Cosmic dust thereby joins lunar samples and meteorites as an additional source of extraterrestrial materials for scientific study. This catalog summarizes preliminary observations on 468 particles retrieved from collection surfaces L2021 and L2036. These surfaces were flat plate Large Area Collectors (with a 300 cm2 surface area each) which was coated with silicone oil (dimethyl siloxane) and then flown aboard a NASA ER-2 aircraft during a series of flights that were made during January and February of 1994 (L2021) and June 7 through July 5 of 1994 (L2036). Collector L2021 was flown across the entire southern margin of the US (California to Florida), and collector L2036 was flown from California to Wallops Island, VA and on to New England. These collectors were installed in a specially constructed wing pylon which ensured that the necessary level of cleanliness was maintained between periods of active sampling. During successive periods of high altitude (20 km) cruise, the collectors were exposed in the stratosphere by barometric controls and then retracted into sealed storage container-s prior to descent. In this manner, a total of 35.8 hours of stratospheric exposure was accumulated for collector L2021, and 26 hours for collector L2036.

  18. Cosmic Gamma-Rays

    Science.gov Websites

    [Argonne Logo] [DOE Logo] Cosmic Gamma-Rays Home Publications Talks People Students Argonne > ; HEP > Cosmic Gamma-Rays Projects VERITAS Past Projects TrICE What's New CTA Cosmic Gamma-Rays The

  19. Cosmic mass spectrometer

    NASA Astrophysics Data System (ADS)

    Anchordoqui, Luis A.; Barger, Vernon; Weiler, Thomas J.

    2018-03-01

    We argue that if ultrahigh-energy (E ≳1010GeV) cosmic rays are heavy nuclei (as indicated by existing data), then the pointing of cosmic rays to their nearest extragalactic sources is expected for 1010.6 ≲ E /GeV ≲1011. This is because for a nucleus of charge Ze and baryon number A, the bending of the cosmic ray decreases as Z / E with rising energy, so that pointing to nearby sources becomes possible in this particular energy range. In addition, the maximum energy of acceleration capability of the sources grows linearly in Z, while the energy loss per distance traveled decreases with increasing A. Each of these two points tend to favor heavy nuclei at the highest energies. The traditional bi-dimensional analyses, which simultaneously reproduce Auger data on the spectrum and nuclear composition, may not be capable of incorporating the relative importance of all these phenomena. In this paper we propose a multi-dimensional reconstruction of the individual emission spectra (in E, direction, and cross-correlation with nearby putative sources) to study the hypothesis that primaries are heavy nuclei subject to GZK photo-disintegration, and to determine the nature of the extragalactic sources. More specifically, we propose to combine information on nuclear composition and arrival direction to associate a potential clustering of events with a 3-dimensional position in the sky. Actually, both the source distance and maximum emission energy can be obtained through a multi-parameter likelihood analysis to accommodate the observed nuclear composition of each individual event in the cluster. We show that one can track the level of GZK interactions on an statistical basis by comparing the maximum energy at the source of each cluster. We also show that nucleus-emitting-sources exhibit a cepa stratis structure on Earth which could be pealed off by future space-missions, such as POEMMA. Finally, we demonstrate that metal-rich starburst galaxies are highly-plausible candidate

  20. Study of cosmic rays reveals secrets of solar-terrestrial science

    NASA Astrophysics Data System (ADS)

    Jokipii, J. R.

    For many years cosmic rays provided the most important source of energetic particles for studies of subatomic physics. Today, cosmic rays are being studied as a natural phenomenon that can tell us much about both the Earth's environment in space and distant astrophysical processes. Cosmic rays are naturally occurring energetic particles—mainly ions—with kinetic energies extending from just above thermal energies to more than 1020 electron volts (eV). They constantly bombard the Earth from all directions, with more than 1018 particles having energies >1 MeV striking the top of the Earth's atmosphere each second. Figure 1 illustrates the continuous cosmic ray energy spectrum.

  1. Cosmic Ray Helium Intensities over the Solar Cycle from ACE

    NASA Technical Reports Server (NTRS)

    DeNolfo, G. A.; Yanasak, N. E.; Binns, W. R.; Cohen, C. M. S.; Cummings, A. C.; Davis, A. J.; George, J. S.; Hink. P. L.; Israel, M. H.; Lave, K.; hide

    2007-01-01

    Observations of cosmic-ray helium energy spectra provide important constraints on cosmic ray origin and propagation. However, helium intensities measured at Earth are affected by solar modulation, especially below several GeV/nucleon. Observations of helium intensities over a solar cycle are important for understanding how solar modulation affects galactic cosmic ray intensities and for separating the contributions of anomalous and galactic cosmic rays. The Cosmic Ray Isotope Spectrometer (CRIS) on ACE has been measuring cosmic ray isotopes, including helium, since 1997 with high statistical precision. We present helium elemental intensities between approx. 10 to approx. 100 MeV/nucleon from the Solar Isotope Spectrometer (SIS) and CRIS observations over a solar cycle and compare these results with the observations from other satellite and balloon-borne instruments, and with GCR transport and solar modulation models.

  2. The Significance of the Influence of the CME Deflection in Interplanetary Space on the CME Arrival at Earth

    NASA Astrophysics Data System (ADS)

    Zhuang, Bin; Wang, Yuming; Shen, Chenglong; Liu, Siqing; Wang, Jingjing; Pan, Zonghao; Li, Huimin; Liu, Rui

    2017-08-01

    As one of the most violent astrophysical phenomena, coronal mass ejections (CMEs) have strong potential space weather effects. However, not all Earth-directed CMEs encounter the Earth and produce geo-effects. One reason is the deflected propagation of CMEs in interplanetary space. Although there have been several case studies clearly showing such deflections, it has not yet been statistically assessed how significantly the deflected propagation would influence the CME’s arrival at Earth. We develop an integrated CME-arrival forecasting (iCAF) system, assembling the modules of CME detection, three-dimensional (3D) parameter derivation, and trajectory reconstruction to predict whether or not a CME arrives at Earth, and we assess the deflection influence on the CME-arrival forecasting. The performance of iCAF is tested by comparing the two-dimensional (2D) parameters with those in the Coordinated Data Analysis Workshop (CDAW) Data Center catalog, comparing the 3D parameters with those of the gradual cylindrical shell model, and estimating the success rate of the CME Earth-arrival predictions. It is found that the 2D parameters provided by iCAF and the CDAW catalog are consistent with each other, and the 3D parameters derived by the ice cream cone model based on single-view observations are acceptable. The success rate of the CME-arrival predictions by iCAF with deflection considered is about 82%, which is 19% higher than that without deflection, indicating the importance of the CME deflection for providing a reliable forecasting. Furthermore, iCAF is a worthwhile project since it is a completely automatic system with deflection taken into account.

  3. Tracking the Momentum Flux of a CME and Quantifying Its Influence on Geomagnetically Induced Currents at Earth

    NASA Technical Reports Server (NTRS)

    Savani, N. P.; Vourlidas, A.; Pulkkinen, A.; Nieves-Chinchilla, T.; Lavraud, B.; Owens, M. J.

    2013-01-01

    We investigate a coronal mass ejection (CME) propagating toward Earth on 29 March 2011. This event is specifically chosen for its predominately northward directed magnetic field, so that the influence from the momentum flux onto Earth can be isolated. We focus our study on understanding how a small Earth-directed segment propagates. Mass images are created from the white-light cameras onboard STEREO which are also converted into mass height-time maps (mass J-maps). The mass tracks on these J-maps correspond to the sheath region between the CME and its associated shockfront as detected by in situ measurements at L1. A time series of mass measurements from the STEREOCOR-2A instrument is made along the Earth propagation direction. Qualitatively, this mass time series shows a remarkable resemblance to the L1 in situ density series. The in situ measurements are used as inputs into a three-dimensional (3-D) magnetospheric space weather simulation from the Community Coordinated Modeling Center. These simulations display a sudden compression of the magnetosphere from the large momentum flux at the leading edge of the CME, and predictions are made for the time derivative of the magnetic field (dBdt) on the ground. The predicted dBdt values were then compared with the observations from specific equatorially located ground stations and showed notable similarity. This study of the momentum of a CME from the Sun down to its influence on magnetic ground stations on Earth is presented as a preliminary proof of concept, such that future attempts may try to use remote sensing to create density and velocity time series as inputs to magnetospheric simulations.

  4. Earth Sciences Changed Influence on the Public Policy Process, or How Congress Stopped Communicating with Geologists

    NASA Astrophysics Data System (ADS)

    McCurdy, K. M.

    2005-12-01

    political hot potato to the scientists. The like-minded community of geologists and public servants that developed in the mid twentieth century was not happenstance, but built from the foundation of the scientific agencies and societies founded in the late nineteenth century. The policy dialect of the late twentieth century was influenced by rational choice terminology and econometric models, not mapping and resource exploration and development. Geology speaks a language increasingly incomprehensible to politicians and their constituents. Re-establishing the strong bonds to the political process is critical for the country. If constituents don't understand why earth science research is important, their elected representatives cannot be expected to vote for public funding. Without the voice of geology, the solutions forged in policy compromises for the many complex physical problems facing the country and the world will be sub-optimal.

  5. Cosmic ray interactions in the ground: Temporal variations in cosmic ray intensities and geophysical studies

    NASA Technical Reports Server (NTRS)

    Lal, D.

    1986-01-01

    Temporal variations in cosmic ray intensity have been deduced from observations of products of interactions of cosmic ray particles in the Moon, meteorites, and the Earth. Of particular interest is a comparison between the information based on Earth and that based on other samples. Differences are expected at least due to: (1) differences in the extent of cosmic ray modulation, and (2) changes in the geomagnetic dipole field. Any information on the global changes in the terrestrial cosmic ray intensity is therefore of importance. In this paper a possible technique for detecting changes in cosmic ray intensity is presented. The method involves human intervention and is applicable for the past 10,000 yrs. Studies of changes over longer periods of time are possible if supplementary data on age and history of the sample are available using other methods. Also discussed are the possibilities of studying certain geophysical processes, e.g., erosion, weathering, tectonic events based on studies of certain cosmic ray-produced isotopes for the past several million years.

  6. Cosmic Radiation Detection and Observations

    NASA Astrophysics Data System (ADS)

    Ramirez Chavez, Juan; Troncoso, Maria

    Cosmic rays consist of high-energy particles accelerated from remote supernova remnant explosions and travel vast distances throughout the universe. Upon arriving at earth, the majority of these particles ionize gases in the upper atmosphere, while others interact with gas molecules in the troposphere and producing secondary cosmic rays, which are the main focus of this research. To observe these secondary cosmic rays, a detector telescope was designed and equipped with two silicon photomultipliers (SiPMs). Each SiPM is coupled to a bundle of 4 wavelength shifting optical fibers that are embedded inside a plastic scintillator sheet. The SiPM signals were amplified using a fast preamplifier with coincidence between detectors established using a binary logic gate. The coincidence events were recorded with two devices; a digital counter and an Arduino micro-controller. For detailed analysis of the SiPM waveforms, a DRS4 sensory digitizer captured the waveforms for offline analysis with the CERN software package Physics Analysis Workstation in a Linux environment. Results from our experiments would be presented. Hartnell College STEM Internship Program.

  7. Space weather influence on the agriculture technology and wheat prices in the medieval England (1259-1703) through cosmic ray/solar activity cycle variations

    NASA Astrophysics Data System (ADS)

    Dorman, L. I.; Pustil'Nik, L. A.; Yom Din, G.

    2003-04-01

    The database of Professor Rogers (1887), which includes wheat prices in England in the Middle Ages (1249-1703) was used to search for possible manifestations of solar activity and cosmic ray intensity variations. The main object of our statistical analysis is investigation of bursts of prices. Our study shows that bursts and troughs of wheat prices take place at extreme states (maximums or minimums) of solar activity cycles. We present a conceptual model of possible modes for sensitivity of wheat prices to weather conditions, caused by cosmic ray intensity solar cycle variations, and compare the expected price fluctuations with wheat price variations recorded in the Medieval England. We compared statistical properties of the intervals between price bursts with statistical properties of the intervals between extremes (minimums) of solar cycles during the years 1700-2000. The medians of both samples have the values of 11.00 and 10.7 years; standard deviations are 1.44 and 1.53 years for prices and for solar activity, respectively. The hypothesis that the frequency distributions are the same for both of the samples have significance level >95%. In the next step we analyzed direct links between wheat prices and cosmic ray cycle variations in the 17th Century, for which both wheat prices and cosmic ray intensity (derived from Be-10 isotope data) are available. We show that for all seven solar activity minimums (cosmic ray intensity maximums) the observed prices were higher than prices for the seven intervals of maximal solar activity (100% sign correlation). This result, combined with the conclusion of similarity of statistical properties of the price and solar activity extremes can be considered as direct evidence of a causal connection between wheat prices bursts and solar activity/cosmic ray intensity extremes.

  8. Influence of other rare earth ions on the optical refrigeration efficiency in Yb:YLF crystals.

    PubMed

    Di Lieto, Alberto; Sottile, Alberto; Volpi, Azzurra; Zhang, Zhonghan; Seletskiy, Denis V; Tonelli, Mauro

    2014-11-17

    We investigated the effect of rare earth impurities on the cooling efficiency of Yb³⁺:LiYF₄ (Yb:YLF). The refrigeration performance of two single crystals, doped with 5%-at. Yb and with identical history but with different amount of contaminations, have been compared by measuring the cooling efficiency curves. Spectroscopic and elemental analyses of the samples have been carried out to identify the contaminants, to quantify their concentrations and to understand their effect on the cooling efficiencies. A model of energy transfer processes between Yb and other rare earth ions is suggested, identifying Erbium and Holmium as elements that produce a detrimental effect on the cooling performance.

  9. Review of the Theoretical and Experimental Status of Dark Matter Identification with Cosmic-Ray Antideuterons

    NASA Technical Reports Server (NTRS)

    Aramaki, T.; Boggs, S.; Bufalino, S.; Dal, L.; von Doetinchem, P.; Donato, F.; Fornengo, N.; Fuke, H.; Grefe, M.; Hailey, C.; hide

    2016-01-01

    Recent years have seen increased theoretical and experimental effort towards the first-ever detection of cosmic-ray antideuterons, in particular as an indirect signature of dark matter annihilation or decay. In contrast to indirect dark matter searches using positrons, antiprotons, or gamma-rays, which suffer from relatively high and uncertain astrophysical backgrounds, searches with antideuterons benefit from very suppressed conventional backgrounds, offering a potential breakthrough in unexplored phase space for dark matter. This article is based on the first dedicated cosmic-ray antideuteron workshop, which was held at UCLA in June 2014. It reviews broad classes of dark matter candidates that result in detectable cosmic-ray antideuteron fluxes, as well as the status and prospects of current experimental searches. The coalescence model of antideuteron production and the influence of antideuteron measurements at particle colliders are discussed. This is followed by a review of the modeling of antideuteron propagation through the magnetic fields, plasma currents, and molecular material of our Galaxy, the solar system, the Earth's geomagnetic field, and the atmosphere. Finally, the three ongoing or planned experiments that are sensitive to cosmic-ray antideuterons, BESS, AMS-02, and GAPS, are detailed. As cosmic-ray antideuteron detection is a rare event search, multiple experiments with orthogonal techniques and backgrounds are essential. Therefore, the combination of AMS-02 and GAPS antideuteron searches is highly desirable. Many theoretical and experimental groups have contributed to these studies over the last decade, this review aims to provide the first coherent discussion of the relevant dark matter theories that antideuterons probe, the challenges to predictions and interpretations of antideuteron signals, and the experimental efforts toward cosmic antideuteron detection.

  10. Explaining TeV cosmic-ray anisotropies with non-diffusive cosmic-ray propagation

    DOE PAGES

    Harding, James Patrick; Fryer, Chris Lee; Mendel, Susan Marie

    2016-05-11

    Constraining the behavior of cosmic ray data observed at Earth requires a precise understanding of how the cosmic rays propagate in the interstellar medium. The interstellar medium is not homogeneous; although turbulent magnetic fields dominate over large scales, small coherent regions of magnetic field exist on scales relevant to particle propagation in the nearby Galaxy. Guided propagation through a coherent field is significantly different from random particle diffusion and could be the explanation of spatial anisotropies in the observed cosmic rays. We present a Monte Carlo code to propagate cosmic particle through realistic magnetic field structures. We discuss the detailsmore » of the model as well as some preliminary studies which indicate that coherent magnetic structures are important effects in local cosmic-ray propagation, increasing the flux of cosmic rays by over two orders of magnitude at anisotropic locations on the sky. Furthermore, the features induced by coherent magnetic structure could be the cause of the observed TeV cosmic-ray anisotropy.« less

  11. EXPLAINING TEV COSMIC-RAY ANISOTROPIES WITH NON-DIFFUSIVE COSMIC-RAY PROPAGATION

    SciTech Connect

    Harding, J. Patrick; Fryer, Chris L.; Mendel, Susan, E-mail: jpharding@lanl.gov, E-mail: fryer@lanl.gov, E-mail: smendel@lanl.gov

    2016-05-10

    Constraining the behavior of cosmic ray data observed at Earth requires a precise understanding of how the cosmic rays propagate in the interstellar medium. The interstellar medium is not homogeneous; although turbulent magnetic fields dominate over large scales, small coherent regions of magnetic field exist on scales relevant to particle propagation in the nearby Galaxy. Guided propagation through a coherent field is significantly different from random particle diffusion and could be the explanation of spatial anisotropies in the observed cosmic rays. We present a Monte Carlo code to propagate cosmic particle through realistic magnetic field structures. We discuss the detailsmore » of the model as well as some preliminary studies which indicate that coherent magnetic structures are important effects in local cosmic-ray propagation, increasing the flux of cosmic rays by over two orders of magnitude at anisotropic locations on the sky. The features induced by coherent magnetic structure could be the cause of the observed TeV cosmic-ray anisotropy.« less

  12. The isotopic composition of cosmic ray calcium

    NASA Technical Reports Server (NTRS)

    Krombel, K. E.; Wiedenbeck, M. E.

    1985-01-01

    Data from the high energy cosmic ray experiment on the international sun earth explorer 3 (ISEE-3) spacecraft have been used to study the isotopic composition of cosmic ray calcium at an energy of approx. 260 MeV/amu. The arriving calcium is found to consist of (32 + or - 6)%. A propagation model consistent with both the light and the subiron secondary element abundances was used for the interpretation of the observed calcium composition. The measured 42Ca+43Ca+44Ca abundance is consistent with the calculated secondary production, while the 40Ca abundance implies a source ratio of 40Ca/Fe = (7.0 + or - 1.7)%.

  13. The possible influence of L-histidine on the origin of the first peptides on the primordial Earth.

    PubMed

    Reiner, Hannes; Plankensteiner, Kristof; Fitz, Daniel; Rode, Bernd Michael

    2006-06-01

    One of the most unsettled problems of prebiotic evolution and the origin of life is the explanation why one enantiomeric form of biomolecules prevailed. In the experiments presented in this paper, the influence of L-histidine on the peptide formation in the Salt-Induced Peptide Formation (SIPF) reaction of the enantiomeric forms of valine, proline, serine, lysine, and tryptophan, and the catalytic effects in this first step toward the first building blocks of proteins on the primordial earth were investigated. In the majority of the produced dipeptides, a remarkable increase of yields was shown, and the preference of the L-amino acids in the peptide formation in most cases cannot be denied. In summary, our data provide further experimental evidence for the plausibility of the SIPF reaction and point at a possible important role of L-histidine in the chemical evolution on the primordial Earth.

  14. A Hubble Cosmic Couple

    NASA Image and Video Library

    2017-12-08

    Here we see the spectacular cosmic pairing of the star Hen 2-427 — more commonly known as WR 124 — and the nebula M1-67 which surrounds it. Both objects, captured here by the NASA/ESA Hubble Space Telescope are found in the constellation of Sagittarius and lie 15,000 light-years away. The star Hen 2-427 shines brightly at the very center of this explosive image and around the hot clumps of surrounding gas that are being ejected into space at over 93,210 miles (150,000 km) per hour. Hen 2-427 is a Wolf–Rayet star, named after the astronomers Charles Wolf and Georges Rayet. Wolf–Rayet are super-hot stars characterized by a fierce ejection of mass. The nebula M1-67 is estimated to be no more than 10,000 years old — just a baby in astronomical terms — but what a beautiful and magnificent sight it makes. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  15. Cosmic Impacts, Cosmic Catastrophes. Part 2.

    ERIC Educational Resources Information Center

    Chapman, Clark R.; Morrison, David

    1990-01-01

    Examined is the science of catastrophism and its role in planetary and earth science. The effects of impacts on earth with extraterrestrial origins are discussed. Perspectives on the age and dynamics of the earth's crust are presented. (CW)

  16. Temperature Effect in Secondary Cosmic Rays (MUONS) Observed at the Ground: Analysis of the Global MUON Detector Network Data

    NASA Astrophysics Data System (ADS)

    de Mendonça, R. R. S.; Braga, C. R.; Echer, E.; Dal Lago, A.; Munakata, K.; Kuwabara, T.; Kozai, M.; Kato, C.; Rockenbach, M.; Schuch, N. J.; Jassar, H. K. Al; Sharma, M. M.; Tokumaru, M.; Duldig, M. L.; Humble, J. E.; Evenson, P.; Sabbah, I.

    2016-10-01

    The analysis of cosmic ray intensity variation seen by muon detectors at Earth's surface can help us to understand astrophysical, solar, interplanetary and geomagnetic phenomena. However, before comparing cosmic ray intensity variations with extraterrestrial phenomena, it is necessary to take into account atmospheric effects such as the temperature effect. In this work, we analyzed this effect on the Global Muon Detector Network (GMDN), which is composed of four ground-based detectors, two in the northern hemisphere and two in the southern hemisphere. In general, we found a higher temperature influence on detectors located in the northern hemisphere. Besides that, we noticed that the seasonal temperature variation observed at the ground and at the altitude of maximum muon production are in antiphase for all GMDN locations (low-latitude regions). In this way, contrary to what is expected in high-latitude regions, the ground muon intensity decrease occurring during summertime would be related to both parts of the temperature effect (the negative and the positive). We analyzed several methods to describe the temperature effect on cosmic ray intensity. We found that the mass weighted method is the one that best reproduces the seasonal cosmic ray variation observed by the GMDN detectors and allows the highest correlation with long-term variation of the cosmic ray intensity seen by neutron monitors.

  17. THE TEMPERATURE EFFECT IN SECONDARY COSMIC RAYS (MUONS) OBSERVED AT THE GROUND: ANALYSIS OF THE GLOBAL MUON DETECTOR NETWORK DATA

    SciTech Connect

    De Mendonça, R. R. S.; Braga, C. R.; Echer, E.

    2016-10-20

    The analysis of cosmic ray intensity variation seen by muon detectors at Earth's surface can help us to understand astrophysical, solar, interplanetary and geomagnetic phenomena. However, before comparing cosmic ray intensity variations with extraterrestrial phenomena, it is necessary to take into account atmospheric effects such as the temperature effect. In this work, we analyzed this effect on the Global Muon Detector Network (GMDN), which is composed of four ground-based detectors, two in the northern hemisphere and two in the southern hemisphere. In general, we found a higher temperature influence on detectors located in the northern hemisphere. Besides that, we noticedmore » that the seasonal temperature variation observed at the ground and at the altitude of maximum muon production are in antiphase for all GMDN locations (low-latitude regions). In this way, contrary to what is expected in high-latitude regions, the ground muon intensity decrease occurring during summertime would be related to both parts of the temperature effect (the negative and the positive). We analyzed several methods to describe the temperature effect on cosmic ray intensity. We found that the mass weighted method is the one that best reproduces the seasonal cosmic ray variation observed by the GMDN detectors and allows the highest correlation with long-term variation of the cosmic ray intensity seen by neutron monitors.« less

  18. Voids and the Cosmic Web: cosmic depression & spatial complexity

    NASA Astrophysics Data System (ADS)

    van de Weygaert, Rien

    2016-10-01

    Voids form a prominent aspect of the Megaparsec distribution of galaxies and matter. Not only do theyrepresent a key constituent of the Cosmic Web, they also are one of the cleanest probesand measures of global cosmological parameters. The shape and evolution of voids are highly sensitive tothe nature of dark energy, while their substructure and galaxy population provides a direct key to thenature of dark matter. Also, the pristine environment of void interiors is an important testing groundfor our understanding of environmental influences on galaxy formation and evolution. In this paper, we reviewthe key aspects of the structure and dynamics ofvoids, with a particular focus on the hierarchical evolution of the void population. We demonstratehow the rich structural pattern of the Cosmic Web is related to the complex evolution and buildupof voids.

  19. The Cosmic Background Explorer.

    ERIC Educational Resources Information Center

    Gulkis, Samuel; And Others

    1990-01-01

    Outlines the Cosmic Background Explorer (COBE) mission to measure celestial radiation. Describes the instruments used and experiments involving differential microwave radiometers, and a far infrared absolute spectrophotometer. (YP)

  20. The astrobiological case for our cosmic ancestry

    NASA Astrophysics Data System (ADS)

    Wickramasinghe, Chandra

    2010-04-01

    With steadily mounting evidence that points to a cosmic origin of terrestrial life, a cultural barrier prevails against admitting that such a connection exists. Astronomy continues to reveal the presence of organic molecules and organic dust on a huge cosmic scale, amounting to a third of interstellar carbon tied up in this form. Just as the overwhelming bulk of organics on Earth stored over geological timescales are derived from the degradation of living cells, so it seems likely that interstellar organics in large measure also derive from biology. As we enter a new decade - the year 2010 - a clear pronouncement of our likely alien ancestry and of the existence of extraterrestrial life on a cosmic scale would seem to be overdue.

  1. The Astrobiological Case for Our Cosmic Ancestry

    NASA Astrophysics Data System (ADS)

    Wickramasinghe, Chandra

    With steadily mounting evidence that points to a cosmic origin of terrestrial life, a cultural barrier prevails against admitting that such a connection exists. Astronomy continues to reveal the presence of organic molecules and organic dust on a huge cosmic scale, amounting to a third of interstellar carbon tied up in this form. Just as the overwhelming bulk of organics on Earth stored over geological timescales are derived from the degradation of living cells, so it seems most likely that interstellar organics in large measure also derive from biology. As we enter a new decade -- the year 2010 -- a clear pronouncement of our likely alien ancestry and of the existence of extraterrestrial life on a cosmic scale would seem to be overdue.

  2. The Earth isn't flat: The (large) influence of topography on geodetic fault slip imaging.

    NASA Astrophysics Data System (ADS)

    Thompson, T. B.; Meade, B. J.

    2017-12-01

    While earthquakes both occur near and generate steep topography, most geodetic slip inversions assume that the Earth's surface is flat. We have developed a new boundary element tool, Tectosaur, with the capability to study fault and earthquake problems including complex fault system geometries, topography, material property contrasts, and millions of elements. Using Tectosaur, we study the model error induced by neglecting topography in both idealized synthetic fault models and for the cases of the MW=7.3 Landers and MW=8.0 Wenchuan earthquakes. Near the steepest topography, we find the use of flat Earth dislocation models may induce errors of more than 100% in the inferred slip magnitude and rake. In particular, neglecting topographic effects leads to an inferred shallow slip deficit. Thus, we propose that the shallow slip deficit observed in several earthquakes may be an artefact resulting from the systematic use of elastic dislocation models assuming a flat Earth. Finally, using this study as an example, we emphasize the dangerous potential for forward model errors to be amplified by an order of magnitude in inverse problems.

  3. Cosmic secrets

    NASA Astrophysics Data System (ADS)

    Schommers, W.

    1. The absolute truth. 1.1. Final truth. 1.2. Two important questions. 1.3. Why does the cosmos exist? 1.4. Are the laws of nature independent of the observer's own nature? 1.5. Self0indulgence was dominant. 1.6. Newton's mechanics and its overestimation. 1.7. Scientific realism. 1.8. An important principle: as little outside world as possible. 1.9. Inside world and outside world. 1.10. Principal questions. 1.11. How does science progress? 1.12. Final remarks -- 2. The projection principle. 2.1. The elements of space and time. 2.2. Relationship between matter and space-time. 2.3. Two relevant features. 2.4. Two kinds of "objects". 2.5. Perception processes. 2.6. Inside world and outside world. 2.7. The influence of evolution. 2.8. Information in the picture versus information in basic reality (outside reality). 2.9. Other biological systems. 2.10. How many (geometrical) objects can be in space-time? 2.11. Two types of space-time? 2.12. Summary -- 3. Fictitious realities. 3.1. Conventional quantum theory: critical remarks. 3.2. The projection principle in connection with fictitious realities. 3.3. Distribution of information. 3.4. Basic transformation effects. 3.5. Pictures within projection theory. 3.6. Auxiliary construction. 3.7. Basic laws. 3.8. Extension of conventional quantum theory. 3.9. Only processes are relevant! 3.10. Interactions. 3.11. Distance-independent interactions. 3.12. Arbitrary jumps within (r, t)-space. 3.13.Mach's principle: preliminary remarks. 3.14. Can a lone, elementary object exist in the cosmos? 3.15. The meaning of the potential functions. 3.16. Time. 3.17. Time travel in physics. 3.18. Summary -- 4. Basic reality and levels of reality. 4.1. Hard objects. 4.2. General physical laws. 4.3. States of mind. 4.4. Outside world and basic reality. 4.5. Objective processes. 4.6. Observations. 4.7. No interactions within (r, t)-space. 4.8. The general cannot be deduced from the particular. 4.9. Remarks on the notion "world equation". 4.10. On

  4. Fundamentals of Aerospace Medicine: Cosmic Radiation

    NASA Technical Reports Server (NTRS)

    Bagshaw, Michael; Cucionotta, Francis A.

    2007-01-01

    Cosmic rays were discovered in 1911 by the Austrian physicist, Victor Hess. The planet earth is continuously bathed in high-energy galactic cosmic ionizing radiation (GCR), emanating from outside the solar system, and sporadically exposed to bursts of energetic particles from the sun referred to as solar particle events (SPEs). The main source of GCR is believed to be supernovae (exploding stars), while occasionally a disturbance in the sun's atmosphere (solar flare or coronal mass ejection) leads to a surge of radiation particles with sufficient energy to penetrate the earth's magnetic field and enter the atmosphere. The inhabitants of planet earth gain protection from the effects of cosmic radiation from the earth s magnetic field and the atmosphere, as well as from the sun's magnetic field and solar wind. These protective effects extend to the occupants of aircraft flying within the earth s atmosphere, although the effects can be complex for aircraft flying at high altitudes and high latitudes. Travellers in space do not have the benefit of this protection and are exposed to an ionizing radiation field very different in magnitude and quality from the exposure of individuals flying in commercial airliners. The higher amounts and distinct types of radiation qualities in space lead to a large need for understanding the biological effects of space radiation. It is recognized that although there are many overlaps between the aviation and the space environments, there are large differences in radiation dosimetry, risks and protection for airline crew members, passengers and astronauts. These differences impact the application of radiation protection principles of risk justification, limitation, and the principle of as low as reasonably achievable (ALARA). This chapter accordingly is divided into three major sections, the first dealing with the basic physics and health risks, the second with the commercial airline experience, and the third with the aspects of cosmic

  5. Recent trends in binary and ternary rare-earth fluoride nanophosphors: How structural and physical properties influence optical behaviour

    DOE PAGES

    Sharma, Rahul Kumar; Mudring, Anja -Verena; Ghosh, Pushpal

    2017-03-28

    Rare-earth (RE) doped binary and ternary fluoride nanomaterials are currently receiving the highest attention as phosphor materials due to their potential for a wide range of photonic and biophotonic applications. This review article aims providing and introduction to the field and giving a critical overview about the latest developments in this fast evolving field. First, the underlying photoluminescence mechanisms like up- and downconversion (UC and DC), charge transfer (CT) and energy transfer (ET) between optically active trivalent RE ions are explained. Then, the influence of particle size and surface, shape and lattice strain, as well as the crystal phase ofmore » the host materials on the optical properties of rare earth based nanomaterias are illustrated. In addition, the effect of surface plasmon resonance (SPR) on the rare earth luminescence is discussed. In the following, different synthesis strategies which have been developed for tuning the crystal phase, shape, size, and morphology of the host nanomaterial are presented. The role of surface modification and functionalization for improving the luminescence intensity, stability, aqueous dispersity/dispersibility and biocompatibility of the materials is discussed. Lastly, photonic applications of RE-doped nanofluorides for energy efficient lighting, improved solar cells and biophotonic applications like photodynamic therapy, and biological detection techniques including in vivo and in vitro bioimaging are presented.« less

  6. Recent trends in binary and ternary rare-earth fluoride nanophosphors: How structural and physical properties influence optical behaviour

    SciTech Connect

    Sharma, Rahul Kumar; Mudring, Anja -Verena; Ghosh, Pushpal

    Rare-earth (RE) doped binary and ternary fluoride nanomaterials are currently receiving the highest attention as phosphor materials due to their potential for a wide range of photonic and biophotonic applications. This review article aims providing and introduction to the field and giving a critical overview about the latest developments in this fast evolving field. First, the underlying photoluminescence mechanisms like up- and downconversion (UC and DC), charge transfer (CT) and energy transfer (ET) between optically active trivalent RE ions are explained. Then, the influence of particle size and surface, shape and lattice strain, as well as the crystal phase ofmore » the host materials on the optical properties of rare earth based nanomaterias are illustrated. In addition, the effect of surface plasmon resonance (SPR) on the rare earth luminescence is discussed. In the following, different synthesis strategies which have been developed for tuning the crystal phase, shape, size, and morphology of the host nanomaterial are presented. The role of surface modification and functionalization for improving the luminescence intensity, stability, aqueous dispersity/dispersibility and biocompatibility of the materials is discussed. Lastly, photonic applications of RE-doped nanofluorides for energy efficient lighting, improved solar cells and biophotonic applications like photodynamic therapy, and biological detection techniques including in vivo and in vitro bioimaging are presented.« less

  7. Maria Montessori's Cosmic Vision, Cosmic Plan, and Cosmic Education

    ERIC Educational Resources Information Center

    Grazzini, Camillo

    2013-01-01

    This classic position of the breadth of Cosmic Education begins with a way of seeing the human's interaction with the world, continues on to the grandeur in scale of time and space of that vision, then brings the interdependency of life where each growing human becomes a participating adult. Mr. Grazzini confronts the laws of human nature in…

  8. The influence of high heat input and inclusions control for rare earth on welding in low alloy high strength steel

    NASA Astrophysics Data System (ADS)

    Chu, Rensheng; Mu, Shukun; Liu, Jingang; Li, Zhanjun

    2017-09-01

    In the current paper, it is analyzed for the influence of high heat input and inclusions control for rare earth on welding in low alloy high strength steel. It is observed for the structure for different heat input of the coarse-grained area. It is finest for the coarse grain with the high heat input of 200 kJ / cm and the coarse grain area with 400 kJ / cm is the largest. The performance with the heat input of 200 kJ / cm for -20 °C V-shaped notch oscillatory power is better than the heat input of 400 kJ / cm. The grain structure is the ferrite and bainite for different holding time. The grain structure for 5s holding time has a grain size of 82.9 μm with heat input of 200 kJ/cm and grain size of 97.9 μm for 10s holding time. For the inclusions for HSLA steel with adding rare earth, they are Al2O3-CaS inclusions in the Al2O3-CaS-CaO ternary phase diagram. At the same time, it can not be found for low melting calcium aluminate inclusions compared to the inclusions for the HSLA steel without rare earth. Most of the size for the inclusions is between 1 ~ 10μm. The overall grain structure is smaller and the welding performance is more excellent for adding rare earth.

  9. Influence of rare earth elements (Nd, Sm, Gd) on the physicochemical properties of ges crystal

    NASA Astrophysics Data System (ADS)

    Madatov, R. S.; Alekperov, A. S.; Magerramova, Dzh. A.

    2015-11-01

    Layered semiconductors (including GeS), which are widely used in modern electronics, are of great interest for researchers. New GeS-based devices have been developed for holographic recording, optical processing, and storage of information. In the last few years, American scientists have developed a unique GeS-based device that makes it possible to accumulate an immense amount of solar energy. The introduction of rare earth elements (REEs) facilitates the healing of metal and chalcogenide vacancies, removes polytypism, and enhances interlayer interaction.

  10. High-Energy Cosmic Rays from Supernovae

    NASA Astrophysics Data System (ADS)

    Morlino, Giovanni

    Cosmic rays are charged relativistic particles that reach the Earth with extremely high energies, providing striking evidence of the existence of effective accelerators in the Universe. Below an energy around ˜ 1017 eV, cosmic rays are believed to be produced in the Milky Way, while above that energy, their origin is probably extragalactic. In the early 1930s, supernovae were already identified as possible sources for the galactic component of cosmic rays. After the 1970s this idea has gained more and more credibility, thanks to the development of the diffusive shock acceleration theory, which provides a robust theoretical framework for particle energization in astrophysical environments. Afterward, mostly in recent years, much observational evidence has been gathered in support of this framework, converting a speculative idea in a real paradigm. In this chapter the basic pillars of this paradigm will be illustrated. This includes the acceleration mechanism, the nonlinear effects produced by accelerated particles onto the shock dynamics needed to reach the highest energies, the escape process from the sources, and the transportation of cosmic rays through the Galaxy. The theoretical picture will be corroborated by discussing several observations which support the idea that supernova remnants are effective cosmic ray factories.

  11. Ultra heavy cosmic ray experiment (A0178)

    NASA Technical Reports Server (NTRS)

    Thompson, A.; Osullivan, D.; Bosch, J.; Keegan, R.; Wenzel, K. P.; Jansen, F.; Domingo, C.

    1992-01-01

    The Ultra Heavy Cosmic Ray Experiment (UHCRE) is based on a modular array of 192 side viewing solid state nuclear track detector stacks. These stacks were mounted in sets of four in 48 pressure vessels using 16 peripheral LDEF trays. The geometry factor for high energy cosmic ray nuclei, allowing for Earth shadowing, was 30 sq m sr, giving a total exposure factor of 170 sq m sr y at an orbital inclination of 28.4 degs. Scanning results indicate that about 3000 cosmic ray nuclei in the charge region with Z greater than 65 were collected. This sample is more than ten times the current world data in the field (taken to be the data set from the HEAO-3 mission plus that from the Ariel-6 mission) and is sufficient to provide the world's first statistically significant sample of actinide cosmic rays. Results are presented including a sample of ultra heavy cosmic ray nuclei, analysis of pre-flight and post-flight calibration events and details of track response in the context of detector temperature history. The integrated effect of all temperature and age related latent track variations cause a maximum charge shift of + or - 0.8e for uranium and + or - 0.6e for the platinum-lead group. Astrophysical implications of the UHCRE charge spectrum are discussed.

  12. JUPITER AS A GIANT COSMIC RAY DETECTOR

    SciTech Connect

    Rimmer, P. B.; Stark, C. R.; Helling, Ch., E-mail: pr33@st-andrews.ac.uk

    We explore the feasibility of using the atmosphere of Jupiter to detect ultra-high-energy cosmic rays (UHECRs). The large surface area of Jupiter allows us to probe cosmic rays of higher energies than previously accessible. Cosmic ray extensive air showers in Jupiter's atmosphere could in principle be detected by the Large Area Telescope (LAT) on the Fermi observatory. In order to be observed, these air showers would need to be oriented toward the Earth, and would need to occur sufficiently high in the atmosphere that the gamma rays can penetrate. We demonstrate that, under these assumptions, Jupiter provides an effective cosmicmore » ray ''detector'' area of 3.3 × 10{sup 7} km{sup 2}. We predict that Fermi-LAT should be able to detect events of energy >10{sup 21} eV with fluence 10{sup –7} erg cm{sup –2} at a rate of about one per month. The observed number of air showers may provide an indirect measure of the flux of cosmic rays ≳ 10{sup 20} eV. Extensive air showers also produce a synchrotron signature that may be measurable by Atacama Large Millimeter/submillimeter Array (ALMA). Simultaneous observations of Jupiter with ALMA and Fermi-LAT could be used to provide broad constraints on the energies of the initiating cosmic rays.« less

  13. Deepening Cosmic Education

    ERIC Educational Resources Information Center

    Leonard, Gerard

    2013-01-01

    This article is a special blend of research, theory, and practice, with clear insight into the origins of Cosmic Education and cosmic task, while recalling memories of student explorations in botany, in particular, episodes from Mr. Leonard's teaching. Mr. Leonard speaks of a storytelling curriculum that eloquently puts perspective into dimensions…

  14. The Cosmic Connection

    Science.gov Websites

    Macy High School We have a simple cosmic ray detector that can be built by high school teachers. This cosmic rays vary with elevation. In addition, it is a valuable tool to teach elementary measurement

  15. The Cosmic Connection

    Science.gov Websites

    The Nuclear Science Division has produced a 25 minute video called The Cosmic Connection. The narrator and author is Tim Middleton, a teacher from Austin, Texas. This video describes cosmic rays and and Mount Diablo are shown. The video is suitable for grades 6 - 12. It can be found at http

  16. Our Cosmic Insignificance

    PubMed Central

    Kahane, Guy

    2014-01-01

    The universe that surrounds us is vast, and we are so very small. When we reflect on the vastness of the universe, our humdrum cosmic location, and the inevitable future demise of humanity, our lives can seem utterly insignificant. Many philosophers assume that such worries about our significance reflect a banal metaethical confusion. They dismiss the very idea of cosmic significance. This, I argue, is a mistake. Worries about cosmic insignificance do not express metaethical worries about objectivity or nihilism, and we can make good sense of the idea of cosmic significance and its absence. It is also possible to explain why the vastness of the universe can make us feel insignificant. This impression does turn out to be mistaken, but not for the reasons typically assumed. In fact, we might be of immense cosmic significance—though we cannot, at this point, tell whether this is the case. PMID:25729095

  17. The influence of internal variability on Earth's energy balance framework and implications for estimating climate sensitivity

    NASA Astrophysics Data System (ADS)

    Dessler, Andrew E.; Mauritsen, Thorsten; Stevens, Bjorn

    2018-04-01

    Our climate is constrained by the balance between solar energy absorbed by the Earth and terrestrial energy radiated to space. This energy balance has been widely used to infer equilibrium climate sensitivity (ECS) from observations of 20th-century warming. Such estimates yield lower values than other methods, and these have been influential in pushing down the consensus ECS range in recent assessments. Here we test the method using a 100-member ensemble of the Max Planck Institute Earth System Model (MPI-ESM1.1) simulations of the period 1850-2005 with known forcing. We calculate ECS in each ensemble member using energy balance, yielding values ranging from 2.1 to 3.9 K. The spread in the ensemble is related to the central assumption in the energy budget framework: that global average surface temperature anomalies are indicative of anomalies in outgoing energy (either of terrestrial origin or reflected solar energy). We find that this assumption is not well supported over the historical temperature record in the model ensemble or more recent satellite observations. We find that framing energy balance in terms of 500 hPa tropical temperature better describes the planet's energy balance.

  18. Influence of rare earth doping on thermoelectric properties of SrTiO3 ceramics

    NASA Astrophysics Data System (ADS)

    Liu, J.; Wang, C. L.; Li, Y.; Su, W. B.; Zhu, Y. H.; Li, J. C.; Mei, L. M.

    2013-12-01

    Thermoelectric properties of SrTiO3 ceramics, doped with different rare earth elements, were investigated in this work. It's found that the ionic radius of doping elements plays an important role on thermoelectric properties: SrTiO3 ceramics doped with large rare earth ions (such as La, Nd, and Sm) exhibit large power factors, and those doped with small ions (such as Gd, Dy, Er, and Y) exhibit low thermal conductivities. Therefore, a simple approach for enhancing the thermoelectric performance of SrTiO3 ceramics is proposed: mainly doped with large ions to obtain a large power factor and, simultaneously, slightly co-doped with small ions to obtain a low thermal conductivity. Based on this rule, Sr0.8La0.18Yb0.02TiO3 ceramics were prepared, whose ZT value at 1 023 K reaches 0.31, increasing by a factor of 19% compared with the single-doped counterpart Sr0.8La0.2TiO3 (ZT = 0.26).

  19. Manifestations of Influence of Solar Activity and Cosmic Ray Intensity on the Wheat Price in the Medieval England (1259-1703 Years)

    NASA Astrophysics Data System (ADS)

    Pustil'Nik, Lev A.; Dorman, L. I.; Yom Din, G.

    2003-07-01

    The database of Professor Rogers, with wheat prices in England in the Middle Ages (1249-1703) was used to search for possible manifestations of solar activity and cosmic ray variations. The main object of the statistical analysis is investigation of bursts of prices. We present a conceptual model of possible modes for sensitivity of wheat prices to weather conditions, caused by solar cycle variations in cosmic rays, and compare the expected price fluctuations with wheat price variations recorded in the Medieval England. We compared statistical properties of the intervals between price bursts with statistical properties of the intervals between extremes (minimums) of solar cycles during the years 1700-2000. Statistical properties of these two samples are similar both in averaged/median values of intervals and in standard deviation of this values. We show that histogram of intervals distribution for price bursts and solar minimums are coincidence with high confidence level. We analyzed direct links between wheat prices and solar activity in the th 17 Century, for which wheat prices and solar activity data as well as cosmic ray intensity (from 10 Be isotop e) are available. We show that for all seven solar activity minimums the observed prices were higher than prices for the nine intervals of maximal solar activity proceed preceding to the minimums. This result, combined with the conclusion on similarity of statistical properties of the price bursts and solar activity extremes we consider as direct evidence of a causal connection between wheat prices bursts and solar activity.

  20. Mid- and far-infrared spectroscopic studies of the influence of temperature, ultraviolet photolysis and ion irradiation on cosmic-type ices.

    PubMed

    Moore, M H; Hudson, R L; Gerakines, P A

    2001-03-15

    Infrared (IR) studies of laboratory ices can provide information on the evolution of cosmic-type ices as a function of different simulated space environments involving thermal, ultraviolet (UV), or ion processing. Laboratory radiation experiments can lead to the formation of complex organic molecules. However, because of our lack of knowledge about UV photon and ion fluxes, and exposure lifetimes, it is not certain how well our simulations represent space conditions. Appropriate laboratory experiments are also limited by the absence of knowledge about the composition, density, and temperature of ices in different regions of space. Our current understanding of expected doses due to UV photons and cosmic rays is summarized here, along with an inventory of condensed-phase molecules identified on outer solar system surfaces, comets and interstellar grains. Far-IR spectra of thermally cycled H2O are discussed since these results reflect the dramatic difference between the amorphous and crystalline phases of H2O ice, the most dominant condensed-phase molecule in cosmic ices. A comparison of mid-IR spectra of products in proton-irradiated and UV-photolyzed ices shows that few differences are observed for these two forms of processing for the simple binary mixtures studied to date. IR identification of radiation products and experiments to determine production rates of new molecules in ices during processing are discussed. A new technique for measuring intrinsic IR band strengths of several unstable molecules is presented. An example of our laboratory results applied to Europa observations is included.

  1. Hubble's Cosmic Bubbles

    NASA Image and Video Library

    2017-12-08

    This entrancing image shows a few of the tenuous threads that comprise Sh2-308, a faint and wispy shell of gas located 5,200 light-years away in the constellation of Canis Major (The Great Dog). Sh2-308 is a large bubble-like structure wrapped around an extremely large, bright type of star known as a Wolf-Rayet Star — this particular star is called EZ Canis Majoris. These type of stars are among the brightest and most massive stars in the Universe, tens of times more massive than our own sun, and they represent the extremes of stellar evolution. Thick winds continually poured off the progenitors of such stars, flooding their surroundings and draining the outer layers of the Wolf-Rayet stars. The fast wind of a Wolf-Rayet star therefore sweeps up the surrounding material to form bubbles of gas. EZ Canis Majoris is responsible for creating the bubble of Sh2-308 — the star threw off its outer layers to create the strands visible here. The intense and ongoing radiation from the star pushes the bubble out farther and farther, blowing it bigger and bigger. Currently the edges of Sh2-308 are some 60 light-years apart! Beautiful as these cosmic bubbles are, they are fleeting. The same stars that form them will also cause their death, eclipsing and subsuming them in violent supernova explosions. Credit: ESA/Hubble & NASA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  2. Modulation of Cosmic Ray Precipitation Related to Climate

    NASA Technical Reports Server (NTRS)

    Feynman, J.; Ruzmaikin, A.

    1998-01-01

    High energy cosmic rays may influence the formation of clouds, and thus can have an impact on weather and climate. Cosmic rays in the solar wind are incident on the magnetosphere boundary and are then transmitted through the magnetosphere and atmosphere to reach the upper troposphere.

  3. Near-Earth Space Radiation Models

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael A.; O'Neill, Patrick M.; O'Brien, T. Paul

    2012-01-01

    Review of models of the near-Earth space radiation environment is presented, including recent developments in trapped proton and electron, galactic cosmic ray and solar particle event models geared toward spacecraft electronics applications.

  4. Scientific Set of Instruments "Solar Cosmic Rays"

    NASA Astrophysics Data System (ADS)

    Kuznetsov, S. N.; Bogomolov, A. V.; Galkin, V. I.; Denisov, Yu. I.; Podorolsky, A. N.; Ryumin, S. P.; Kudela, K.; Rojko, J.

    A set of scientific instruments SCR (Solar Cosmic Rays) was developed by the scientists of SINP MSU and IEP SAS in order to study relations between the radiation conditions in the near-Earth space and solar activity. This set of instruments was installed on board the satellites CORONAS-I and CORONAS-F launched to the orbit on March 2, 1994, and July 30, 2001, respectively. Detailed description of the instruments is presented.

  5. On the influence of Aerosols in measurement of electric field from Earth surface using a Field-Mill

    NASA Astrophysics Data System (ADS)

    Ghosh, Abhijit; Sundar De, Syam; Paul, Suman; Hazra, Pranab; Guha, Gautam

    2016-07-01

    Aerosol particles influence the electrical conductivity of air. The value is reduced through the removal of small ions responsible for the conductivity. The metropolitan city, Kolkata (latitude 22.56° N, longitude 88.5° E) is densely populated surrounded by various types of Industries. Air is highly invaded by pollutant particles here for which the city falls under small-scale fair-weather condition where electric field and air-earth current get perturbed by ionization and different aerosols produced locally. Fine particles having diameter < 0.1 μm (Aitken nuclei) are distributed in air which decreases the electrical conductivity and increases the columnar resistance. Aerosol particles steadily change the status at different times of the day through coagulation, sedimentation, charge-transfer initiated by precipitation. The diurnal variation of potential gradient is caused mainly due to urbanization, emission from industry and traffic. The rate of production of haze (atmospheric suspension) and their vertical transportation control the daily variation of atmospheric potential. The nuclei of pollutant particles combine with ions and decrease the concentration of small ions thereby reducing the conductivity. The pollutants, influenced by CO _{2} and other green house gas emission from fossil fuels are also responsible for the variation of electric field. Variation in consumption of Oil and Gasoline due to traffic in the city contributes a high Aitken count and there are changes in atmospheric dispersion following reduction of conductivity of the medium. Outcome of some important measurement of potential gradient and air-earth current will be presented. Different parameters like air-conductivity, relative abundance of smoke, visibility would offer new signatures of aerosol-influence on electric potential gradient. Some of those will be reported here.

  6. The influence of the Earth's magnetosphere on the high-energy solar protons

    NASA Technical Reports Server (NTRS)

    Bazilevskaya, G. A.; Makhmutov, V. S.; Charakhchyan, T. N.

    1985-01-01

    In the Earth's polar regions the intensity of the solar protons with the energy above the critical energy of geomagnetic cutoff is the same as in the interplanetary space. The penumbra in the polar regions is small and the East-West effect is also small. However the geomagnetic cutoff rigidity R sub c in polar regions is difficult to calculate because it is not sufficient to include only the internal sources of the geomagnetic field. During the magneto-quiescent periods the real value of R sub c can be less by 0.1 GV than the calculated value because of the external sources. During the geomagnetic storms the real value of R sub c is still lower.

  7. Influence of rare earth ions on microstructural and optical properties of ZnO nanostructures

    SciTech Connect

    Riyajuddin, Sk., E-mail: riyaj5303@gmail.com; Ahmad, Shabbir; Faizan, M.

    2016-05-23

    Pure and 3% rare earth ions (Nd{sup 3+} & Gd{sup 3+}) doped ZnO samples were synthesized by sol-gel method, followed by annealing at temperature 450°C for 2hr. The samples were characterized by XRD, FTIR and UV-visible spectroscopy. XRD result confirmed single phase nature of all samples with crystalline structure. The average crystallite size of the doped samples found to be decreases as caculated using Debye-Scherrer’s formula. FTIR spectra indicate absorption band centered at 464 cm{sup −1} which is attributed to Zn-O lattice vibration. It confirms the formaton of compounds. UV-visible spectroscopy was used to study the optical properties and band gapmore » of the synthesised materials using Tauc’s relation.« less

  8. Influence of clouds on UV-B penetration to the earth's surface

    NASA Technical Reports Server (NTRS)

    Green, A. E. S.

    1979-01-01

    Radiometric measurements of cloud influence on ultraviolet B radiation (UV-B) were obtained. Mathematical models of the influence were defined to lay the groundwork for the construction of the global UV-B climatology from satellite determined ozone data. More refined measurements comparing UV-B radiation with total solar radiation were carried out. The cloudy case is referred to the cloudless sky irradiance and convenient transmission ratios are given An approach to the inversion of scattering data is summarized. An improved characterization of the UV-B radiation from a cloudless sky is also presented.

  9. Influence of geomagnetic activity and earth weather changes on heart rate and blood pressure in young and healthy population

    NASA Astrophysics Data System (ADS)

    Ozheredov, V. A.; Chibisov, S. M.; Blagonravov, M. L.; Khodorovich, N. A.; Demurov, E. A.; Goryachev, V. A.; Kharlitskaya, E. V.; Eremina, I. S.; Meladze, Z. A.

    2017-05-01

    There are many references in the literature related to connection between the space weather and the state of human organism. The search of external factors influence on humans is a multi-factor problem and it is well known that humans have a meteo-sensitivity. A direct problem of finding the earth weather conditions, under which the space weather manifests itself most strongly, is discussed in the present work for the first time in the helio-biology. From a formal point of view, this problem requires identification of subset (magnetobiotropic region) in three-dimensional earth's weather parameters such as pressure, temperature, and humidity, corresponding to the days when the human body is the most sensitive to changes in the geomagnetic field variations and when it reacts by statistically significant increase (or decrease) of a particular physiological parameter. This formulation defines the optimization of the problem, and the solution of the latter is not possible without the involvement of powerful metaheuristic methods of searching. Using the algorithm of differential evolution, we prove the existence of magnetobiotropic regions in the earth's weather parameters, which exhibit magneto-sensitivity of systolic, diastolic blood pressure, and heart rate of healthy young subjects for three weather areas (combinations of atmospheric temperature, pressure, and humidity). The maximum value of the correlation confidence for the measurements attributable to the days of the weather conditions that fall into each of three magnetobiotropic areas is an order of 0.006, that is almost 10 times less than the confidence, equal to 0.05, accepted in many helio-biological researches.

  10. Influence of geomagnetic activity and earth weather changes on heart rate and blood pressure in young and healthy population.

    PubMed

    Ozheredov, V A; Chibisov, S M; Blagonravov, M L; Khodorovich, N A; Demurov, E A; Goryachev, V A; Kharlitskaya, E V; Eremina, I S; Meladze, Z A

    2017-05-01

    There are many references in the literature related to connection between the space weather and the state of human organism. The search of external factors influence on humans is a multi-factor problem and it is well known that humans have a meteo-sensitivity. A direct problem of finding the earth weather conditions, under which the space weather manifests itself most strongly, is discussed in the present work for the first time in the helio-biology. From a formal point of view, this problem requires identification of subset (magnetobiotropic region) in three-dimensional earth's weather parameters such as pressure, temperature, and humidity, corresponding to the days when the human body is the most sensitive to changes in the geomagnetic field variations and when it reacts by statistically significant increase (or decrease) of a particular physiological parameter. This formulation defines the optimization of the problem, and the solution of the latter is not possible without the involvement of powerful metaheuristic methods of searching. Using the algorithm of differential evolution, we prove the existence of magnetobiotropic regions in the earth's weather parameters, which exhibit magneto-sensitivity of systolic, diastolic blood pressure, and heart rate of healthy young subjects for three weather areas (combinations of atmospheric temperature, pressure, and humidity). The maximum value of the correlation confidence for the measurements attributable to the days of the weather conditions that fall into each of three magnetobiotropic areas is an order of 0.006, that is almost 10 times less than the confidence, equal to 0.05, accepted in many helio-biological researches.

  11. Quantifying cosmic variance

    NASA Astrophysics Data System (ADS)

    Driver, Simon P.; Robotham, Aaron S. G.

    2010-10-01

    We determine an expression for the cosmic variance of any `normal' galaxy survey based on examination of M* +/- 1 mag galaxies in the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) data cube. We find that cosmic variance will depend on a number of factors principally: total survey volume, survey aspect ratio and whether the area surveyed is contiguous or comprising independent sightlines. As a rule of thumb cosmic variance falls below 10 per cent once a volume of 107h-30.7Mpc3 is surveyed for a single contiguous region with a 1:1 aspect ratio. Cosmic variance will be lower for higher aspect ratios and/or non-contiguous surveys. Extrapolating outside our test region we infer that cosmic variance in the entire SDSS DR7 main survey region is ~7 per cent to z < 0.1. The equation obtained from the SDSS DR7 region can be generalized to estimate the cosmic variance for any density measurement determined from normal galaxies (e.g. luminosity densities, stellar mass densities and cosmic star formation rates) within the volume range 103-107h-30.7Mpc3. We apply our equation to show that two sightlines are required to ensure that cosmic variance is <10 per cent in any ASKAP galaxy survey (divided into Δ z ~ 0.1 intervals, i.e. ~1Gyr intervals for z < 0.5). Likewise 10 MeerKAT sightlines will be required to meet the same conditions. GAMA, VVDS and zCOSMOS all suffer less than 10 per cent cosmic variance (~3-8 per cent) in Δ z intervals of 0.1, 0.25 and 0.5, respectively. Finally we show that cosmic variance is potentially at the 50-70 per cent level, or greater, in the Hubble Space Telescope (HST) Ultra Deep Field depending on assumptions as to the evolution of clustering. 100 or 10 independent sightlines will be required to reduce cosmic variance to a manageable level (<10 per cent) for HST ACS or HST WFC3 surveys, respectively (in Δ z ~ 1 intervals). Cosmic variance is therefore a significant factor in the z > 6 HST studies currently underway.

  12. How Does Boiling in the Earth's Crust Influence Metal Speciation and Transport?

    NASA Astrophysics Data System (ADS)

    Kam, K.; Lemke, K.

    2014-12-01

    The presence of large quantities of precious metals, such as gold and copper, near the Earth's surface (upper crust) is commonly attributed to transport in aqueous solution and precipitation upon variations in temperature and pressure. As a consequence, gold exploration is closely linked to solution chemistry, i.e. hydrothermal processes involving aqueous fluids with densities of around unity. However, as crustal fluids buoyantly ascend, boiling produces a coexisting low-density aqueous liquid with fundamentally different physical and chemical properties, and a, most importantly, a high affinity for coinage metals (Heinrich et al., Econ Geol., 1992, 87, 1566). From recent experimental studies of Au (Hurtig and Williams-Jones, 2014, Geochim. Cosmochim. Acta,, 127, 304), we know that metal speciation in this low-density phase differs fundamentally from that observed in bulk solution, clearly, with important implications for Au, and metal speciation in general, transport and ore concentrations processes (these processes would also be operable in industrial geothermal plants given the quite special solvent properties of steam). In brief, this study focuses on the speciation of select metal halides in bulk solution as well as in water vapor, and is driven by our need to understand the solvent properties of around 2.0x109 cubic kilometers of free water (or 2,500 times as much water as stored in all lakes and rivers) present in the Earth's crust. The scope of this study has particular applications in the geothermal and oil industries, as both deal with high temperature low-density aqueous fluids. Understanding how metal halide species behave upon boiling can also provide insight into how metals, such as copper and silver, coat turbine equipment and steam piping in geothermal plants, ultimately rendering these components inoperable. This study will also provide preliminary results from mass spectrometric experiments of transition metal halides, and will be augmented with

  13. Obliquity histories of Earth and Mars: Influence of inertial and dissipative core-mantle coupling

    NASA Technical Reports Server (NTRS)

    Bills, Bruce G.

    1990-01-01

    For both the Earth and Mars, secular variations in the angular separation of the spin axis from the orbit normal are suspected of driving major climatic changes. There is considerable interest in determining the amplitude and timing of these obliquity variations. If the orientation of the orbital plane were inertially fixed, and the planet were to act as a rigid body in it response to precessional torques, the spin axis would simply precess around the orbit at a fixed obliquity and at a uniform angular rate. The precession rate parameter depends on the principal moments of inertia and rotation rate of the perturbed body, and on the gravitational masses and semiminor axes of the perturbing bodies. For Mars, the precession rate is not well known, but probably lies in the interval 8 to 10 arcsec/year. Gravitational interactions between the planets lead to secular motions of the orbit planes. In the rigid body case, the spin axis still attempts to precess about the instantaneous orbit normal, but now the obliquity varies. The hydrostatic figure of a planet represents a compromise between gravitation, which attempts to attain spherical symmetry, and rotation, which prefers cylindrical symmetry. Due to their higher mean densities the cores of the Earth and Mars will be more nearly spherical than the outer layers of these planets. On short time scales it is appropriate to consider the core to be an inviscid fluid constrained to move with the ellipsoidal region bounded by the rigid mantle. The inertial coupling provided by this mechanism is effective whenever the ellipticicy of the container exceeds the ratio of precessional to rotational rates. If the mantle were actually rigid, this would be an extremely effective type of coupling. However, on sufficiently long time scales, the mantle will deform viscously and can accommodate the motions of the core fluid. A fundamentally different type of coupling is provided by electromagnetic or viscous torques. This type of coupling

  14. Influence of crude oil cracking on distribution of hydrocarbons in the Earth's interior (experimental data)

    NASA Astrophysics Data System (ADS)

    Balitsky, V. S.; Balitskaya, L. V.; Penteley, S. V.; Novikova, M. A.

    2012-02-01

    The compositions and phase conditions of water-hydrocarbon fluids in synthetic quartz inclusions were studied by the methods of microthermometry, local IR spectroscopy, and gas-liquid chromatography. Synthetic quartz was grown in near-neutral fluoride, low-alkali bicarbonate, and alkali carbonate solutions with crude oil and its major fractions. The crystals with fluid inclusions were grown under thermal gradient conditions at relatively low temperatures (240-280°C) and pressures (6-45 MPa). After the study, the inclusions of grown crystals were subject to thermal processing in autoclaves at 350-380°C and 80-125 MPa. As a result, the initial water-hydrocarbon inclusions underwent significant changes. Hydrocarbon gases, largely methane and residual solid bitumens, appeared in their composition; the gasoline-kerosene fraction content increased substantially in liquid hydrocarbons (HCs). These changes are caused, first of all, by crude oil cracking, which is manifested already at 330°C and attains its maximum activity at 350-500°C (pressure of saturated vapor and higher). In natural conditions with increase in depths and, thus, the thermobaric parameters, this process is inevitable. According to the obtained experimental data, this very phenomenon and the existence of real thermal and baric gradients in the Earth's interior provide for the formation of vertical zoning in the distribution of hydrocarbon deposits of different types.

  15. Influence of ocean tides on the diurnal and semidiurnal earth rotation variations from VLBI observations

    NASA Astrophysics Data System (ADS)

    Gubanov, V. S.; Kurdubov, S. L.

    2015-05-01

    The International astrogeodetic standard IERS Conventions (2010) contains a model of the diurnal and semidiurnal variations in Earth rotation parameters (ERPs), the pole coordinates and the Universal Time, arising from lunisolar tides in the world ocean. This model was constructed in the mid-1990s through a global analysis of Topex/Poseidon altimetry. The goal of this study is to try to estimate the parameters of this model by processing all the available VLBI observations on a global network of stations over the last 35 years performed within the framework of IVS (International VLBI Service) geodetic programs. The complexity of the problemlies in the fact that the sought-for corrections to the parameters of this model lie within 1 mm and, thus, are at the limit of their detectability by all currently available methods of ground-based positional measurements. This requires applying universal software packages with a high accuracy of reduction calculations and a well-developed system of controlling the simultaneous adjustment of observational data to analyze long series of VLBI observations. This study has been performed with the QUASAR software package developed at the Institute of Applied Astronomy of the Russian Academy of Sciences. Although the results obtained, on the whole, confirm a high accuracy of the basic model in the IERS Conventions (2010), statistically significant corrections that allow this model to be refined have been detected for some harmonics of the ERP variations.

  16. Direct observations of galactic cosmic rays

    NASA Astrophysics Data System (ADS)

    Müller, Dietrich

    2012-08-01

    The mysterious " radiation ... entering our atmosphere from above" discovered by Hess in 1912 is now known to be dominated by relativistic charged particles, mostly with energies in the GeV-range, but extending to energies higher by many orders of magnitude. As none of these particles can penetrate the earth's atmosphere without interaction, detailed studies of their composition and energy spectra require observations with high-altitude balloons or spacecraft. This became possible only towards the middle of the 20th century. The direct measurements have now revealed much detail about the Galactic cosmic rays below 1015eV, but do not yet provide much overlap with the air-shower region of energies. A historic overview of the measurements is given, beginning with the realization that the majority of the cosmic rays are protons. The discovery and astrophysical significance of the heavier nuclei, and of the ultra-heavy nuclei beyond iron and up to the actinides, are then described, and measurements of the isotopic composition are discussed. Observations of the individual energy spectra are reviewed, and finally, the detection of electrons, positrons, and anti-protons in the cosmic rays, and the searches for exotic or unusual phenomena are summarized. Emphasis is given to the fact that all of these discoveries have become possible through the evolution of increasingly sophisticated detection techniques, a process that is continuing through the present time. The precise knowledge of the abundance distributions of the elements in the cosmic rays and of their isotopic composition permits a comparison with the "universal abundance scale" and provides strong constraints on the origin of the cosmic-ray material in the interstellar medium. "Clock-isotopes" reveal the time history of the particles. The shapes of the energy spectra of the individual cosmic-ray components are related to evolving ideas about particle acceleration and propagation in the Galaxy. In conclusion

  17. Toward a descriptive model of galactic cosmic rays in the heliosphere

    NASA Technical Reports Server (NTRS)

    Mewaldt, R. A.; Cummings, A. C.; Adams, James H., Jr.; Evenson, Paul; Fillius, W.; Jokipii, J. R.; Mckibben, R. B.; Robinson, Paul A., Jr.

    1988-01-01

    Researchers review the elements that enter into phenomenological models of the composition, energy spectra, and the spatial and temporal variations of galactic cosmic rays, including the so-called anomalous cosmic ray component. Starting from an existing model, designed to describe the behavior of cosmic rays in the near-Earth environment, researchers suggest possible updates and improvements to this model, and then propose a quantitative approach for extending such a model into other regions of the heliosphere.

  18. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1991-01-01

    The annual progress report on Cosmic X Ray Physics for the period 1 Jan. to 31 Dec. 1990 is presented. Topics studied include: soft x ray background, new sounding rocket payload: x ray calorimeter, and theoretical studies.

  19. Cosmic x ray physics

    NASA Technical Reports Server (NTRS)

    Mccammon, Dan; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

    1990-01-01

    The annual progress report on Cosmic X Ray Physics is presented. Topics studied include: the soft x ray background, proportional counter and filter calibrations, the new sounding rocket payload: X Ray Calorimeter, and theoretical studies.

  20. Cosmic-ray tracing

    NASA Astrophysics Data System (ADS)

    Becker Tjus, Julia

    2018-04-01

    Active galactic nuclei are firm favourites to be revealed as the source of cosmic rays, but solid evidence has proven elusive. A model taking both local and global nuclei propagation into account may help to close the deal.

  1. Cosmic Ray Astronomy

    NASA Technical Reports Server (NTRS)

    Wu, S. T.

    2000-01-01

    The cosmic ray division participation in the cooperative agreement was activated in the second year. The scientific goals will be analysis of cosmic ray data from the Japanese-American Cooperative Emulsion Experiments (JACEE). Measurements of primary cosmic rays in the JACEE emulsion chambers will be made to derive for each detected particle the deposited energy in the chamber and the primary charge (atomic number). The data will be corrected to the primary flux above the atmosphere, and the composition and energy spectra will be derived. The spectra of the individual elements will be interpreted in context with the supernova shock and other models of cosmic ray acceleration. Additional information is contained in the original extended abstract.

  2. A Cosmic Variance Cookbook

    NASA Astrophysics Data System (ADS)

    Moster, Benjamin P.; Somerville, Rachel S.; Newman, Jeffrey A.; Rix, Hans-Walter

    2011-04-01

    Deep pencil beam surveys (<1 deg2) are of fundamental importance for studying the high-redshift universe. However, inferences about galaxy population properties (e.g., the abundance of objects) are in practice limited by "cosmic variance." This is the uncertainty in observational estimates of the number density of galaxies arising from the underlying large-scale density fluctuations. This source of uncertainty can be significant, especially for surveys which cover only small areas and for massive high-redshift galaxies. Cosmic variance for a given galaxy population can be determined using predictions from cold dark matter theory and the galaxy bias. In this paper, we provide tools for experiment design and interpretation. For a given survey geometry, we present the cosmic variance of dark matter as a function of mean redshift \\bar{z} and redshift bin size Δz. Using a halo occupation model to predict galaxy clustering, we derive the galaxy bias as a function of mean redshift for galaxy samples of a given stellar mass range. In the linear regime, the cosmic variance of these galaxy samples is the product of the galaxy bias and the dark matter cosmic variance. We present a simple recipe using a fitting function to compute cosmic variance as a function of the angular dimensions of the field, \\bar{z}, Δz, and stellar mass m *. We also provide tabulated values and a software tool. The accuracy of the resulting cosmic variance estimates (δσ v /σ v ) is shown to be better than 20%. We find that for GOODS at \\bar{z}=2 and with Δz = 0.5, the relative cosmic variance of galaxies with m *>1011 M sun is ~38%, while it is ~27% for GEMS and ~12% for COSMOS. For galaxies of m * ~ 1010 M sun, the relative cosmic variance is ~19% for GOODS, ~13% for GEMS, and ~6% for COSMOS. This implies that cosmic variance is a significant source of uncertainty at \\bar{z}=2 for small fields and massive galaxies, while for larger fields and intermediate mass galaxies, cosmic variance is

  3. COSMIC monthly progress report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Activities of the Computer Software Management and Information Center (COSMIC) are summarized for the month of January 1994. Tables showing the current inventory of programs available from COSMIC are presented and program processing and evaluation activities are discussed. Marketing and customer service activities in this period are presented as is the progress report of NASTRAN maintenance and support. Tables of disseminations and budget summary conclude the report.

  4. Strong Cosmic Censorship

    NASA Astrophysics Data System (ADS)

    Isenberg, James

    2017-01-01

    The Hawking-Penrose theorems tell us that solutions of Einstein's equations are generally singular, in the sense of the incompleteness of causal geodesics (the paths of physical observers). These singularities might be marked by the blowup of curvature and therefore crushing tidal forces, or by the breakdown of physical determinism. Penrose has conjectured (in his `Strong Cosmic Censorship Conjecture`) that it is generically unbounded curvature that causes singularities, rather than causal breakdown. The verification that ``AVTD behavior'' (marked by the domination of time derivatives over space derivatives) is generically present in a family of solutions has proven to be a useful tool for studying model versions of Strong Cosmic Censorship in that family. I discuss some of the history of Strong Cosmic Censorship, and then discuss what is known about AVTD behavior and Strong Cosmic Censorship in families of solutions defined by varying degrees of isometry, and discuss recent results which we believe will extend this knowledge and provide new support for Strong Cosmic Censorship. I also comment on some of the recent work on ``Weak Null Singularities'', and how this relates to Strong Cosmic Censorship.

  5. Cross section parameterizations for cosmic ray nuclei. 1: Single nucleon removal

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Townsend, Lawrence W.

    1992-01-01

    Parameterizations of single nucleon removal from electromagnetic and strong interactions of cosmic rays with nuclei are presented. These parameterizations are based upon the most accurate theoretical calculations available to date. They should be very suitable for use in cosmic ray propagation through interstellar space, the Earth's atmosphere, lunar samples, meteorites, spacecraft walls and lunar and martian habitats.

  6. The Cosmic Shoreline

    NASA Technical Reports Server (NTRS)

    Zahnle, Kevin J.; Catling, D. C.

    2013-01-01

    Volatile escape is the classic existential problem of planetary atmospheres. The problem has gained new currency now that we can study the cumulative effects of escape from extrasolar planets. Escape itself is likely to be a rapid process, relatively unlikely to be caught in the act, but the cumulative effects of escape in particular, the distinction between planets with and without atmospheres should show up in the statistics of the new planets. The new planets make a moving target. It can be difficult to keep up, and every day the paper boy brings more. Of course most of these will be giant planets loosely resembling Saturn or Neptune albeit hotter and nearer their stars, as big hot fast-orbiting exoplanets are the least exceedingly difficult to discover. But they are still planets, all in all, and although twenty years ago experts could prove on general principles that they did not exist, we have come round rather quickly, and they should be welcome now at LPSC. Here we will discuss the empirical division between planets with and without atmospheres. For most exoplanets the question of whether a planet has or has not an atmosphere is a fuzzy inference based on the planet's bulk density. A probably safe presumption is that a low density planet is one with abundant volatiles, in the general mold of Saturn or Neptune. On the other hand a high density low mass planet could be volatile-poor, in the general mold of Earth or Mercury. We will focus on planets, mostly seen in transit, for which both radius and mass are measured, as these are the planets with measured densities. More could be said: a lot of subtle recent work has been devoted to determining the composition of planets from equations of state or directly observing atmospheres in transit, but we will not go there. What interests us here is that, from the first, the transiting extrasolar planets appear to have fit into a pattern already seen in our own Solar System, as shown in Fig. 1. We first noticed this

  7. Satellite Constellations for Space Weather and Ionospheric Studies: Overview of the COSMIC and COSMIC-2 Missions

    NASA Astrophysics Data System (ADS)

    Schreiner, W. S.; Pedatella, N. M.; Weiss, J.

    2016-12-01

    Measurements from constellations of low Earth orbiting (LEO) satellites are proving highly useful for ionospheric science and space weather studies. The Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC), a joint US/Taiwan mission launched in April 2006, is a six micro-satellite constellation carrying Global Positioning System (GPS) radio occultation (RO) receivers. COSMIC has collected a large amount of useful data from these scientific payloads and is still currently collecting up to 1,000 RO measurement events per day on average. The GPS RO dual-frequency L-band phase and amplitude measurements can be used to observe absolute Total Electron Content (TEC) and scintillation on lines of sight between the LEO and GPS satellites, and electron density profiles via the RO method. The large number and complete global and local time coverage of COSMIC data are allowing scientists to observe ionospheric and plasmaspheric phenomena that are difficult to see with other instruments. The success of COSMIC has prompted U.S. agencies and Taiwan to execute a COSMIC follow-on mission (called COSMIC-2) that will put twelve satellites with GNSS (Global Navigation Satellite System) RO payloads into orbit on two launches in the 2017-20 time frame. The first launch in 2017 will place six satellites in a 520-km altitude 24 deg inclination orbit, which is ideal for low latitude ionospheric research and space weather forecasting. The planned second launch (not currently funded) places six additional satellites in a 750 km 72 deg inclination orbit to provide global coverage and increased sampling density. COSMIC-2 will make use of an advanced radio occultation receiver with an innovative beam-forming antenna design, and is expected to produce at least 10,000 high-quality atmospheric and ionospheric profiles per day from GPS and GLONASS signals to support operational weather prediction, climate monitoring, and space weather forecasting. Each COSMIC-2 spacecraft

  8. Rare earth indates (RE: La-Yb): influence of the synthesis route and heat treatment on the crystal structure.

    PubMed

    Shukla, Rakesh; Grover, Vinita; Srinivasu, Kancharlapalli; Paul, Barnita; Roy, Anushree; Gupta, Ruma; Tyagi, Avesh Kumar

    2018-05-15

    Rare earth indates are an interesting class of compounds with rich crystallography. The present study explores the crystallographic phases observed in REInO3 (RE: La-Yb) systems and their dependence on synthesis routes and annealing temperature. All REInO3 compositions were synthesized by a solid state route as well as gel-combustion synthesis (GC) followed by annealing at different temperatures. The systems were well characterized by powder XRD studies and were analysed by Rietveld refinement for the structural parameters. The cell parameters were observed to decrease in accordance with the trend in ionic radii on proceeding from lighter to heavier rare earth ions. Interestingly, the synthesis route and the annealing temperature had a profound bearing on the phase relationships observed in the REInO3 series. The solid state synthesized samples depicted an orthorhombic phase (Pbnm) field for LaInO3 to SmInO3, followed by a hexagonal-type phase (P63cm) for GdInO3 to DyInO3. However, the phase field distribution was greatly influenced upon employing gel-combustion (GC) wherein both single-phasic hexagonal and orthorhombic phase fields were found to shrink. Annealing the GC-synthesized compositions to still higher temperatures (1250 °C) further evolved the phase boundaries. An important outcome of the study is observance of polymorphism in SmInO3 which crystallized in the hexagonal phase when synthesized by GC and orthorhombic phase by solid state synthesis. This reveals the all-important role played by synthesis conditions. The existence and energetics of the two polymorphs have been elucidated and discussed with the aid of theoretical studies.

  9. Factors that Influence the Price of Al, Cd, Co, Cu, Fe, Ni, Pb, Rare Earth Elements, and Zn

    USGS Publications Warehouse

    Papp, John F.; Bray, E. Lee; Edelstein, Daniel L.; Fenton, Michael D.; Guberman, David E.; Hedrick, James B.; Jorgenson, John D.; Kuck, Peter H.; Shedd, Kim B.; Tolcin, Amy C.

    2008-01-01

    This report is based on a presentation delivered at The 12th International Battery Materials Recycling Seminar, March 17-20, 2008, Fort Lauderdale, Fla., about the factors that influence prices for aluminum, cadmium, cobalt, copper, iron, lead, nickel, rare earth elements, and zinc. These are a diverse group of metals that are of interest to the battery recycling industry. Because the U.S. Geological Survey (USGS) closely monitors, yet neither buys nor sells, metal commodities, it is an unbiased source of metal price information and analysis. The authors used information about these and other metals collected and published by the USGS (U.S. production, trade, stocks, and prices and world production) and internationally (consumption and stocks by country) from industry organizations, because metal markets are influenced by activities and events over the entire globe. Long-term prices in this report, represented by unit values, were adjusted to 1998 constant dollars to remove the effects of inflation. A previous USGS study in this subject area was 'Economic Drivers of Mineral Supply' by Lorie A. Wagner, Daniel E. Sullivan, and John L. Sznopek (USGS Open File Report 02-335). By seeking a common cause for common behavior of prices among the various metal commodities, the authors found that major factors that influence prices of metal commodities were international events such as wars and recessions, and national events such as the dissolution of the Soviet Union in 1991 and economic growth in China, which started its open door policy in the 1970s but did not have significant market impact until the 1990s. Metal commodity prices also responded to commodity-specific events such as tariff or usage changes or mine strikes. It is shown that the prices of aluminum, cadmium, copper, iron, lead, nickel, and zinc are at historic highs, that world stocks are at (or near) historic lows, and that China's consumption of these metals had increased substantially, making it the world

  10. Cosmic rays flux and geomagnetic field variations at midlatitudes

    NASA Astrophysics Data System (ADS)

    Morozova, Anna; Ribeiro, Paulo; Tragaldabas Collaboration Team

    2014-05-01

    It is well known that the cosmic rays flux is modulated by the solar wind and the Earth's magnetic field. The Earth's magnetic field deflects charged particles in accordance with their momentum and the local field strength and direction. The geomagnetic cutoffs depend both on the internal and the external components of the geomagnetic field, therefore reflecting the geodynamo and the solar activity variations. A new generation, high performance, cosmic ray detector Tragaldabas was recently installed at the University of Santiago de Compostela (Spain). The detector has been acquiring test data since September 2013 with a rate of about 80 events/s over a solid angle of ~5 srad. around the vertical direction. To take full advantage of this new facility for the study of cosmic rays arriving to the Earth, an international collaboration has been organized, of about 20 researchers from 10 laboratories of 5 European countries. The Magnetic Observatory of Coimbra (Portugal) has been measuring the geomagnetic field components for almost 150 years since the first measurements in 1866. It is presently equipped with up-to-date instruments. Here we present a preliminary analysis of the global cosmic ray fluxes acquired by the new Tragaldabas detector in relation to the geomagnetic field variations measured by the Coimbra observatory. We also compare the data from the new cosmic rays detector with results obtained by the Castilla-La Mancha Neutron Monitor (CaLMa, Gadalajara, Spain) that is in operation since October 2011.

  11. Nearest Cosmic Mirage

    NASA Astrophysics Data System (ADS)

    2003-07-01

    Discovery of quadruply lensed quasar with Einstein ring Summary Using the ESO 3.6-m telescope at La Silla (Chile), an international team of astronomers [1] has discovered a complex cosmic mirage in the southern constellation Crater (The Cup). This "gravitational lens" system consists of (at least) four images of the same quasar as well as a ring-shaped image of the galaxy in which the quasar resides - known as an "Einstein ring". The more nearby lensing galaxy that causes this intriguing optical illusion is also well visible. The team obtained spectra of these objects with the new EMMI camera mounted on the ESO 3.5-m New Technology Telescope (NTT), also at the La Silla observatory. They find that the lensed quasar [2] is located at a distance of 6,300 million light-years (its "redshift" is z = 0.66 [3]) while the lensing elliptical galaxy is rougly halfway between the quasar and us, at a distance of 3,500 million light-years (z = 0.3). The system has been designated RXS J1131-1231 - it is the closest gravitationally lensed quasar discovered so far . PR Photo 20a/03 : Image of the gravitational lens system RXS J1131-1231 (ESO 3.6m Telescope). PR Photo 20b/03 : Spectra of two lensed images of the source quasar and the lensing galaxy. Cosmic mirages The physical principle behind a "gravitational lens" (also known as a "cosmic mirage") has been known since 1916 as a consequence of Albert Einstein's Theory of General Relativity . The gravitational field of a massive object curves the local geometry of the Universe, so light rays passing close to the object are bent (like a "straight line" on the surface of the Earth is necessarily curved because of the curvature of the Earth's surface). This effect was first observed by astronomers in 1919 during a total solar eclipse. Accurate positional measurements of stars seen in the dark sky near the eclipsed Sun indicated an apparent displacement in the direction opposite to the Sun, about as much as predicted by Einstein

  12. Low-energy cosmic ray protons from nuclear interactions of cosmic rays with the interstellar medium.

    NASA Technical Reports Server (NTRS)

    Wang, H. T.

    1973-01-01

    The intensity of low-energy (less than 100 MeV) protons from nuclear interactions of higher-energy (above 100 MeV) cosmic rays with the interstellar medium is calculated. The resultant intensity in the 10- to 100-MeV range is larger by a factor of 3-5 than the observed proton intensity near earth. The calculated intensity from nuclear interactions constitutes a lower limit on the actual proton intensity in interstellar space.

  13. Influence of rare earth content on Mm-based AB 5 metal hydride alloys for Ni-MH batteries-An X-ray fluorescence study

    NASA Astrophysics Data System (ADS)

    Ananth, M. V.; Raju, M.; Manimaran, K.; Balachandran, G.; Nair, Lekshmi M.

    AB 5-type MH alloys with Mm (Misch metal) as the A part (with varied rare earth contents in Mm) were investigated for rare earth by XRF analysis and battery performance by life cycle tests with an objective of understanding the influence of rare earth content on electrochemical hydrogen storage. The La/Ce ratio was found to vary from 0.51 to 18.73. The capacity output varied between 179 and 266 mAh g -1. The results show that the La/Ce ratio has a strong influence on the performance, with the best performance realized with samples having an La/Ce ratio of around 12. La enhancement facilitates easy activation due to refinement in grain size and interstitial dimensions. Also, an orderly influence on crystalline structure could be seen. The study demonstrates that the rare earth content is an essential factor in determining the maximum capacity output because of its influence on crystal orientation as well as an increase in the radius of the interstitials, lattice constants and cell volumes.

  14. Processes Influencing the Timing and Volume of Eruptions From the Youngest Supervolcano on Earth

    NASA Astrophysics Data System (ADS)

    Wilson, C. J. N.; Barker, S. J.; Morgan, D. J.; Rowland, J. V.; Schipper, I.

    2015-12-01

    In their stratigraphic records, silicic caldera volcanoes display wide ranges of eruptive styles and volumes. However, relationships between frequency and magnitude are often complex, and the forecasting of future activity is inherently problematic. Taupo volcano, New Zealand, provides a unique opportunity to investigate eruptive histories from a hyperactive, large silicic magmatic system with eruptive volumes that span 3-4 orders of magnitude, and show no clear relationships with the repose period. Taupo hosted the world's most recent supereruption at 25.4 ka, which discharged 530 km3 of magma in the episodic 10-phase Oruanui event. Only 5 kyr later, Taupo revived, with 3 dacitic eruptions from 21.5-17 ka and 25 rhyolite eruptions from 12-1.7 ka. Here we use trends in whole rock, glass and mineral chemistry to show how the magma system reestablished following the Oruanui event, and to consider what processes influence the state of the modern volcano. The post-Oruanui dacites reflect the first products of the rebuilding silicic magma system, as most of the Oruanui mush was reconfigured or significantly modified in composition following thermal fluxing accompanying post-caldera collapse readjustment. Compositional variations within the younger rhyolites at <12 ka reflect fine-scale temporal changes in mineral phase stability, closely linked to the development, stabilization and maturation of a new silicic mush system. For the most recent eruptions, the system underwent destabilization, resulting in increased volumes of melt extraction from the silicic mush. Orthopyroxene Fe-Mg diffusion timescales indicate that the onset of rapid heating and priming of the silicic mush occurred <100 years prior to the <2.15 ka eruptions, with subsequent melt accumulation occurring in only decades. The largest post-Oruanui eruption at 232 AD culminated from elevated mafic magma supply to the silicic mush pile, rapid melt accumulation and high differential tectonic stress build up

  15. IMF Prediction with Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Bieber, J. W.; Evenson, P. A.; Kuwabara, T.; Pei, C.

    2013-12-01

    Cosmic rays impacting Earth have passed through and interacted with the interplanetary magnetic field (IMF) surrounding Earth, and in some sense they carry information on the three-dimensional structure of that field. This work uses neutron monitor data in an effort to extract that information and use it to predict the future behavior of the IMF, especially the north-south component (Bz) which is so crucial in determining geomagnetic activity. We consider 161 events from a published list of interplanetary coronal mass ejections and compare hourly averages of the predicted field with the actual field measured later. We find that the percentage of events with 'good' predictions of Bz (in the sense of having a positive correlation between the prediction and the subsequent measurement) varies from about 85% for predictions 1 hour into the future to about 60% for predictions 4 hours into the future. We present several ideas for how the method might be improved in future implementations. Supported by NASA grant NNX08AQ01G and NSF grant ANT-0739620.

  16. Relative likelihood for life as a function of cosmic time

    SciTech Connect

    Loeb, Abraham; Batista, Rafael A.; Sloan, David, E-mail: aloeb@cfa.harvard.edu, E-mail: rafael.alvesbatista@physics.ox.ac.uk, E-mail: david.sloan@physics.ox.ac.uk

    2016-08-01

    Is life most likely to emerge at the present cosmic time near a star like the Sun? We address this question by calculating the relative formation probability per unit time of habitable Earth-like planets within a fixed comoving volume of the Universe, dP ( t )/ dt , starting from the first stars and continuing to the distant cosmic future. We conservatively restrict our attention to the context of ''life as we know it'' and the standard cosmological model, ΛCDM . We find that unless habitability around low mass stars is suppressed, life is most likely to exist near ∼more » 0.1 M {sub ⊙} stars ten trillion years from now. Spectroscopic searches for biosignatures in the atmospheres of transiting Earth-mass planets around low mass stars will determine whether present-day life is indeed premature or typical from a cosmic perspective.« less

  17. Mining cosmic dust from the blue ice lakes of Greenland

    NASA Technical Reports Server (NTRS)

    Maurette, M.; Brownlee, D. E.; Fehrenback, L.; Hammer, C.; Jehano, C.; Thomsen, H. H.

    1985-01-01

    Extraterrestrial material, most of which invisible settles to Earth's surface as dust particles smaller than a millimeter in size were investigated. Particles of 1/10 millimeter size fall at a rate of one/sq m/yr collection of extraterrestrial dust is important because the recovered cosmic dust particles can provide important information about comets. Comets are the most important source of dust in the solar system and they are probably the major source of extraterrestrial dust that is collectable at the Earth's surface. A new collection site for cosmic dust, in an environment where degradation by weathering is minimal is reported. It is found that the blue ice lakes on the Greenland ice cap provide an ideal location for collection of extraterrestrial dust particles larger than 0.1 mm in size. It is found that the lakes contain large amounts of cosmic dust which is much better preserved than similar particles recovered from the ocean floor.

  18. Cosmic distance duality and cosmic transparency

    NASA Astrophysics Data System (ADS)

    Nair, Remya; Jhingan, Sanjay; Jain, Deepak

    2012-12-01

    We compare distance measurements obtained from two distance indicators, Supernovae observations (standard candles) and Baryon acoustic oscillation data (standard rulers). The Union2 sample of supernovae with BAO data from SDSS, 6dFGS and the latest BOSS and WiggleZ surveys is used in search for deviations from the distance duality relation. We find that the supernovae are brighter than expected from BAO measurements. The luminosity distances tend to be smaller then expected from angular diameter distance estimates as also found in earlier works on distance duality, but the trend is not statistically significant. This further constrains the cosmic transparency.

  19. DETERMINATION OF INDUCED RADIOACTIVITY IN THE SECOND COSMIC SPACESHIP

    SciTech Connect

    Matveev, V.V.; Sokolov, A.D.

    1961-01-01

    The residual gamma activity in a biological specimen on board the second Soviet cosmic spaceship was determined. The biological specimens were in the form of cylinders (3.8-cm dia., 4-cm long) with a total weight of 86 g. The activity of the specimens was measured after return to earth, and it was found that if there was a residual gamma activity 15 days after the return to earth it did not exceed 10-/sup 10/ g equivalents of Ra. (OTS)

  20. Heliospheric Impact on Cosmic Rays Modulation

    NASA Astrophysics Data System (ADS)

    Tiwari, Bhupendra Kumar

    2016-07-01

    Heliospheric Impact on Cosmic RaysModulation B. K. Tiwari Department of Physics, A. P. S. University, Rewa (M.P.), btiwari70@yahoo.com Cosmic rays (CRs) flux at earth is modulated by the heliosphereric magnetic field and the structure of the heliosphere, controls by solar outputs and their variability. Sunspots numbers (SSN) is often treated as a primary indicator of solar activity (SA). GCRs entering the helioshphere are affected by the interplanetary magnetic field (IMF) and solar wind speed, their modulation varies with the varying solar activity. The observation based on data recoded from Omniweb data Centre for solar- interplanetary activity indices and monthly mean count rate of cosmic ray intensity (CRI) data from neutron monitors of different cut-off rigidities(Rc) (Moscow Rc=2.42Gv and Oulu Rc=0.80Gv). During minimum solar activity periodof solar cycle 23/24, the sun is remarkably quiet, weakest strength of the IMF and least dense and slowest, solar wind speed, whereas, in 2003, highest value of yearly averaged solar wind speed (~568 Km/sec) associated with several coronal holes, which generate high speed wind stream has been recorded. It is observed that GCRs fluxes reduces and is high anti-correlated with SSN (0.80) and IMF (0.86). CRI modulation produces by a strong solar flare, however, CME associated solar flare produce more disturbance in the interplanetary medium as well as in geomagnetic field. It is found that count rate of cosmic ray intensity and solar- interplanetary parameters were inverse correlated and solar indices were positive correlated. Keywords- Galactic Cosmic rays (GCRs), Sunspot number (SSN), Solar activity (SA), Coronal Mass Ejection (CME), Interplanetary magnetic field (IMF)

  1. Terrestrial effects of high energy cosmic rays

    NASA Astrophysics Data System (ADS)

    Atri, Dimitra

    On geological timescales, the Earth is likely to be exposed to higher than the usual flux of high energy cosmic rays (HECRs) from astrophysical sources such as nearby supernovae, gamma ray bursts or by galactic shocks. These high-energy particles strike the Earth's atmosphere, initiating an extensive air shower. As the air shower propagates deeper, it ionizes the atmosphere by producing charged secondary particles and photons. Increased ionization leads to changes in atmospheric chemistry, resulting in ozone depletion. This increases the flux of solar UVB radiation at the surface, which is potentially harmful to living organisms. Increased ionization affects the global electrical circuit, which could enhance the low-altitude cloud formation rate. Secondary particles such as muons and thermal neutrons produced as a result of hadronic interactions of the primary cosmic rays with the atmosphere are able to reach the ground, enhancing the biological radiation dose. The muon flux dominates the radiation dose from cosmic rays causing damage to DNA and an increase in mutation rates and cancer, which can have serious biological implications for surface and sub-surface life. Using CORSIKA, we perform massive computer simulations and construct lookup tables for 10 GeV - 1 PeV primaries, which can be used to quantify these effects from enhanced cosmic ray exposure to any astrophysical source. These tables are freely available to the community and can be used for other studies. We use these tables to study the terrestrial implications of galactic shock generated by the infall of our galaxy toward the Virgo cluster. Increased radiation dose from muons could be a possible mechanism explaining the observed periodicity in biodiversity in paleobiology databases.

  2. Cosmic ray strangelets

    NASA Astrophysics Data System (ADS)

    Madsen, Jes

    2005-06-01

    Searching for strangelets in cosmic rays may be the best way to test the possible stability of strange quark matter. I review calculations of the astrophysical strangelet flux in the GV TV rigidity range, which will be investigated from the Alpha Magnetic Spectrometer (AMS-02) on the International Space Station, and discuss the merits of strangelets as ultra-high energy cosmic rays at EeV ZeV energies, beyond the Greisen Zatsepin Kuzmin cutoff. I also address some 'counter-arguments' sometimes raised against the possibility of stable strangelets. It will be argued that stability of strange quark matter remains a viable possibility, which must be tested by experiments.

  3. Cosmic rays and terrestrial life: A brief review

    NASA Astrophysics Data System (ADS)

    Atri, Dimitra; Melott, Adrian L.

    2014-01-01

    “The investigation into the possible effects of cosmic rays on living organisms will also offer great interest.” - Victor F. Hess, Nobel Lecture, December 12, 1936 High-energy radiation bursts are commonplace in our Universe. From nearby solar flares to distant gamma ray bursts, a variety of physical processes accelerate charged particles to a wide range of energies, which subsequently reach the Earth. Such particles contribute to a number of physical processes occurring in the Earth system. A large fraction of the energy of charged particles gets deposited in the atmosphere, ionizing it, causing changes in its chemistry and affecting the global electric circuit. Remaining secondary particles contribute to the background dose of cosmic rays on the surface and parts of the subsurface region. Life has evolved over the past ∼3 billion years in presence of this background radiation, which itself has varied considerably during the period [1-3]. As demonstrated by the Miller-Urey experiment, lightning plays a very important role in the formation of complex organic molecules, which are the building blocks of more complex structures forming life. There is growing evidence of increase in the lightning rate with increasing flux of charged particles. Is there a connection between enhanced rate of cosmic rays and the origin of life? Cosmic ray secondaries are also known to damage DNA and cause mutations, leading to cancer and other diseases. It is now possible to compute radiation doses from secondary particles, in particular muons and neutrons. Have the variations in cosmic ray flux affected the evolution of life on earth? We describe the mechanisms of cosmic rays affecting terrestrial life and review the potential implications of the variation of high-energy astrophysical radiation on the history of life on earth.

  4. Cosmic Ray Induced Neutron Irradiation

    NASA Astrophysics Data System (ADS)

    Overholt, Andrew

    2011-11-01

    After cancer studies performed on flight crews during the 1970s, it was found that cosmic rays produce a signficant flux of thermal neutrons at airplane altitudes. In the case of high energy cosmic rays these biologically threatening neutrons are increased at ground level. Our work models the flux of neutrons produced by high energy cosmic rays, exploring the possibility of biological impact due to extended periods of increase high energy cosmic ray flux.

  5. An Inexpensive Cosmic Ray Detector for the Classroom

    ERIC Educational Resources Information Center

    Goldader, Jeffrey D.; Choi, Seulah

    2010-01-01

    Finding ways to demonstrate--in a high school classroom--that subatomic particles from space produce other particles capable of reaching the Earth's surface is not a trivial task. In this paper, we describe a Geiger-Muller tube-based cosmic ray coincidence detector we produced at a total cost of less than $200, using two tubes purchased used…

  6. Cosmic Education: Linking the Human to the Universe.

    ERIC Educational Resources Information Center

    Gebhardt-Seele, Peter

    2002-01-01

    Describes cosmic education as the Montessori guide for educating 6- to 12-year-olds. Discusses practical consequences of Montessori's ideas, including the selection of the "great story," the need for physics at the elementary level to teach the laws of nature, the citizen's responsibility for the earth's survival, the importance of…

  7. Ionospheric Electron Density Measurements Using COSMIC

    NASA Astrophysics Data System (ADS)

    Dymond, K. F.; Budzien, S. A.; Bernhardt, P. A.; Rocken, C.; Syndergaard, S.

    2007-12-01

    At 0140 UTC on April 15, 2006, the joint Taiwan-U.S. COSMIC/FORMOSAT-3 (Constellation Observing System for Meteorology, Ionosphere, and Climate and Formosa Satellite mission #3; hereafter COSMIC) mission, a constellation of six micro-satellites, was launched into a 512-km orbit from Vandenberg Air Force Base in California. Using on-board propulsion these satellites have been deployed to their final orbits at 800 km with 30 degrees of separation. This process has taken about 17 months following the launch. There are three instruments aboard each COSMIC satellite: the GPS Occultation Experiment (GOX), the Tri-Band Beacon (TBB), and the Tiny Ionospheric Photometer (TIP). These three instruments constitute a unique suite of instruments for studying the Earth's ionosphere. The GOX instrument operates by inferring the slant total electron content (the integral of the electron density along the line-of-sight) between the COSMIC satellites and the GPS satellites as a function of tangent height above the Earth's limb. These data can be inverted to produce electron density profiles in the E and F regions of the ionosphere. The TBB is a three frequency radio beacon that radiates coherently at 150, 400, and 1067 MHz. When the relative phases of the signals are measured between the COSMIC satellites and ground-based or space-based receivers, the total electron content along the line-of-sight can be determined. By making the measurements from a set of receivers, the two-dimensional distribution of electrons beneath the satellite can be determined using tomographic techniques. The TIP instrument measures the optical signature of the natural decay of the ionosphere produced via ecombination of the O+ ions and electrons. The TIP measurements can be used to characterize the morphology and dynamics of the global ionosphere. Additionally, the TIP measurements can be inverted in conjunction with the GPS occultation measurements, using tomographic techniques, to produce the two

  8. The Near-Earth Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Xapsos, Michael

    2008-01-01

    This viewgraph presentation reviews the effects of the Near-Earth space radiation environment on NASA missions. Included in this presentation is a review of The Earth s Trapped Radiation Environment, Solar Particle Events, Galactic Cosmic Rays and Comparison to Accelerator Facilities.

  9. Reconstructing the Chronology of Supernovae: Determining Major Variations in the History of the Cosmic-ray Flux Incident on the Earth's Surface by Measuring the Concentration of 22Ne in Halite

    NASA Astrophysics Data System (ADS)

    Nahill, N. D.; Giegengack, R.; Lande, K.; Omar, G.

    2008-12-01

    We plan to measure the inventory of cosmogenically produced 22Ne atoms preserved in the mineral lattice of halite in deposits of rock salt, and to use that inventory to measure variations in the cosmic-ray flux to enable us to reconstruct the history of supernovae. Bedded rock salt consists almost entirely of the mineral halite (NaCl). Any neon trapped in the halite crystals during precipitation is primarily 20Ne, with a 22Ne concentration of 9% or less. Any neon resulting from cosmic-ray interactions with 23Na is solely 22Ne; therefore, 22Ne atoms in excess of 9% of the total neon are cosmogenic in origin. Measurement of the 22Ne inventory in halite from deposits covering a range of geologic ages may enable us to document the systematic growth of 22Ne through geologic time and, thus, establish the cosmic-ray flux and a chronology of supernovae. The cosmic-ray flux is attenuated in direct proportion to the mass of material overlying a halite deposit. To adjust the 22Ne inventory to account for that attenuation, we must reconstruct the post-depositional history of accumulation and removal of superjacent sediment for each halite deposit we study. As an example of our procedure, we reconstruct here the shielding history of the Permian halite deposit, the Salado Formation, Delaware Basin, New Mexico. The stratigraphy of the Delaware Basin has been well documented via exploration and production wells drilled in search of oil and gas, exploration boreholes associated with potash mining, and comprehensive geologic site assessment of the DOE Waste Isolation Pilot Plant (WIPP). WIPP is a subsurface repository for the permanent disposal of transuranic wastes, located in southeastern New Mexico, 42 km east of Carlsbad and approximately 655 m beneath the surface in the Salado Fm. The Salado Fm is part of the Late Permian Ochoan Series, and consists of 1) a lower member, 2) the McNutt Potash Zone, and 3) an upper member. WIPP lies between marker bed (MB)139 and MB136 in the

  10. Radiation Hazard from Galactic Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Farahat, Ashraf

    2006-03-01

    Space radiation is a major hazard to astronauts in long-duration human space explosion. Astronauts are exposed to an enormous amount of radiation during their missions away from the Earth in outer space. Deep space is a rich environment of protons, gamma rays and cosmic rays. A healthy 40 years old man staying on Earth away from large doses of radiation stands a 20% chance of dying from cancer. If the same person travels into a 3- year Mars mission, the added risk should increase by 19%. This indicates that there is 39% chance of having cancer after he comes back to Earth. Female astronaut chances to get cancer is even almost double the above percentage. The greatest threat to astronauts en route to the red planet is galactic cosmic rays (GCR). GCRs penetrate through the skin of spaceships and people like tiny firearm bullets, breaking the strands of DNA molecules, damaging genes, and killing cells. Understanding the nature of the GCRs, their effect on biological cells, and their interactions with different shielding materials is the key point to shield against them in long space missions. In this paper we will present a model to evaluate the biological effects of GCRs and suggestion different ways to shield against them.

  11. Virtual impact: visualizing the potential effects of cosmic impact in human history

    SciTech Connect

    Masse, W Bruce; Janecky, David R; Forte, Maurizio

    2009-01-01

    Current models indicate that catastrophic impacts by asteroids and comets capable of killing more than one quarter of Earth's human population have occurred on average once every million years; smaller impacts, such the 1908 Tunguska impact that leveled more than 2,000 square km of Siberian forest, occur every 200-300 years. Therefore, cosmic impact likely significantly affected hominine evolution and conceivably played a role in Holocene period human culture history. Regrettably, few archaeologists are trained to appreciate the nature and potential effects of cosmic impact. We have developed a conceptual model for an extensible set of educational and research tools basedmore » on virtual reality collaborative environments to engage archaeologists and the general public on the topic of the role of cosmic impact in human history. Our initial focus is on two documented asteroid impacts in Argentina during the period of 4000 to 1000 B.C. Campo del Cicio resulted in an energy release of around 2-3 megatons (100-150 times the Hiroshima atomic weapon), and left several craters and a strewn field covering 493 km{sup 2} in northeastern Argentina. Rio Cuarto was likely more than 1000 megatons and may have devastated an area greater than 50,000 km{sup 2} in central Argentina. We are focusing on reconstructions of these events and their potential effects on contemporary hunter and gatherers. Our vinual reality tools also introduce interactive variables (e.g., impactor physical properties, climate, vegetation, topography, and social complexity) to allow researchers and students to better investigate and evaluate the factors that significantly influence cosmic impact effects.« less

  12. Cosmic Microwave Background Timeline

    Science.gov Websites

    about 2.3 K 1948: George Gamow, Ralph Alpher, and Robert Herman predict that a Big Bang universe perfect blackbody spectrum and thereby strongly supporting the hot big bang model, the thermal history of anisotropy in the cosmic microwave background, this strongly supports the big bang model with gravitational

  13. Other Cosmic Ray Links

    Science.gov Websites

    curriculum for its course Physics In and Through Cosmology. The Distributed Observatory aims to become the world's largest cosmic ray telescope, using the distributed sensing and computing power of the world's cell phones. Modeled after the distributed computing efforts of SETI@Home and Folding@Home, the

  14. Chandra Discovers Cosmic Cannonball

    NASA Astrophysics Data System (ADS)

    2007-11-01

    One of the fastest moving stars ever seen has been discovered with NASA's Chandra X-ray Observatory. This cosmic cannonball is challenging theories to explain its blistering speed. Astronomers used Chandra to observe a neutron star, known as RX J0822-4300, over a period of about five years. During that span, three Chandra observations clearly show the neutron star moving away from the center of the Puppis A supernova remnant. This remnant is the stellar debris field created during the same explosion in which the neutron star was created about 3700 years ago. Chandra X-ray Image of RX J0822-4300 in Puppis A Chandra X-ray Image of RX J0822-4300 in Puppis A By combining how far it has moved across the sky with its distance from Earth, astronomers determined the neutron star is moving at over 3 million miles per hour. At this rate, RX J0822-4300 is destined to escape from the Milky Way after millions of years, even though it has only traveled about 20 light years so far. "This star is moving at 3 million miles an hour, but it's so far away that the apparent motion we see in five years is less than the height of the numerals in the date on a penny, seen from the length of a football field," said Frank Winkler of Middlebury College in Vermont. "It's remarkable, and a real testament to the power of Chandra, that such a tiny motion can be measured." Labeled Image of RX J0822-4300 in Puppis A Labeled Image of RX J0822-4300 in Puppis A "Just after it was born, this neutron star got a one-way ticket out of the Galaxy," said co-author Robert Petre of NASA's Goddard Space Flight Center in Greenbelt, Md. "Astronomers have seen other stars being flung out of the Milky Way, but few as fast as this." So-called hypervelocity stars have been previously discovered shooting out of the Milky Way with speeds around one million miles per hour. One key difference between RX J0822-4300 and these other reported galactic escapees is the source of their speed. The hypervelocity stars are

  15. Cosmic Rays: "A Thin Rain of Charged Particles."

    ERIC Educational Resources Information Center

    Friedlander, Michael

    1990-01-01

    Discussed are balloons and electroscopes, understanding cosmic rays, cosmic ray paths, isotopes and cosmic-ray travel, sources of cosmic rays, and accelerating cosmic rays. Some of the history of the discovery and study of cosmic rays is presented. (CW)

  16. Tracing the cosmic web

    NASA Astrophysics Data System (ADS)

    Libeskind, Noam I.; van de Weygaert, Rien; Cautun, Marius; Falck, Bridget; Tempel, Elmo; Abel, Tom; Alpaslan, Mehmet; Aragón-Calvo, Miguel A.; Forero-Romero, Jaime E.; Gonzalez, Roberto; Gottlöber, Stefan; Hahn, Oliver; Hellwing, Wojciech A.; Hoffman, Yehuda; Jones, Bernard J. T.; Kitaura, Francisco; Knebe, Alexander; Manti, Serena; Neyrinck, Mark; Nuza, Sebastián E.; Padilla, Nelson; Platen, Erwin; Ramachandra, Nesar; Robotham, Aaron; Saar, Enn; Shandarin, Sergei; Steinmetz, Matthias; Stoica, Radu S.; Sousbie, Thierry; Yepes, Gustavo

    2018-01-01

    The cosmic web is one of the most striking features of the distribution of galaxies and dark matter on the largest scales in the Universe. It is composed of dense regions packed full of galaxies, long filamentary bridges, flattened sheets and vast low-density voids. The study of the cosmic web has focused primarily on the identification of such features, and on understanding the environmental effects on galaxy formation and halo assembly. As such, a variety of different methods have been devised to classify the cosmic web - depending on the data at hand, be it numerical simulations, large sky surveys or other. In this paper, we bring 12 of these methods together and apply them to the same data set in order to understand how they compare. In general, these cosmic-web classifiers have been designed with different cosmological goals in mind, and to study different questions. Therefore, one would not a priori expect agreement between different techniques; however, many of these methods do converge on the identification of specific features. In this paper, we study the agreements and disparities of the different methods. For example, each method finds that knots inhabit higher density regions than filaments, etc. and that voids have the lowest densities. For a given web environment, we find a substantial overlap in the density range assigned by each web classification scheme. We also compare classifications on a halo-by-halo basis; for example, we find that 9 of 12 methods classify around a third of group-mass haloes (i.e. Mhalo ∼ 1013.5 h-1 M⊙) as being in filaments. Lastly, so that any future cosmic-web classification scheme can be compared to the 12 methods used here, we have made all the data used in this paper public.

  17. Ground albedo neutrons produced by cosmic radiations

    NASA Astrophysics Data System (ADS)

    Kodama, M.

    1983-05-01

    Day-to-day variations of cosmic-ray-produced neutron fluxes near the earth's ground surface are measured by using three sets of paraffin-moderated BF3 counters, which are installed in different locations, 3 m above ground, ground level, and 20 cm under ground. Neutron flux decreases observed by these counters when snowcover exists show that there are upward-moving neutrons, that is, ground albedo neutron near the ground surface. The amount of albedo neutrons is estimated to be about 40 percent of total neutron flux in the energy range 1-10 to the 6th eV.

  18. Atmospheric cosmic rays and solar energetic particles at aircraft altitudes.

    PubMed

    O'Brien, K; Friedberg, W; Sauer, H H; Smart, D F

    1996-01-01

    Galactic cosmic rays, which are thought to be produced and accelerated by a variety of mechanisms in the Milky Way galaxy, interact with the solar wind, the earth's magnetic field, and its atmosphere to produce hadron, lepton, and photon fields at aircraft altitudes that are quite unlike anything produced in the laboratory. The energy spectra of these secondary particles extend from the lowest possible energy to energies over an EeV. In addition to cosmic rays, energetic particles, generated on the sun by solar flares or coronal mass ejections, bombard the earth from time to time. These particles, while less energetic than cosmic rays, also produce radiation fields at aircraft altitudes which have qualitatively the same properties as cosmic rays. The authors have calculated atmospheric cosmic-ray angular fluxes, spectra, scalar fluxes, and ionization, and compared them with experimental data. Agreement with these data is seen to be good. These data have been used to calculate equivalent doses in a simplified human phantom at aircraft altitudes and the estimated health risks to aircraft crews. The authors have also calculated the radiation doses from several large solar energetic particle events (known as GLEs, or Ground Level Events), which took place in 1989, including the very large event known as GLE 42, which took place on September 29th and 30th of that year. The spectra incident on the atmosphere were determined assuming diffusive shock theory. Unfortunately, there are essentially no experimental data with which to compare these calculations.

  19. Cosmic ray injection spectrum at the galactic sources

    NASA Astrophysics Data System (ADS)

    Lagutin, Anatoly; Tyumentsev, Alexander; Volkov, Nikolay

    The spectra of cosmic rays measured at Earth are different from their source spectra. A key to understanding this difference, being crucial for solving the problem of cosmic-ray origin, is the determination of how cosmic-ray (CR) particles propagate through the turbulent interstellar medium (ISM). If the medium is a quasi-homogeneous the propagation process can be described by a normal diffusion model. However, during a last few decades many evidences, both from theory and observations, of the existence of multiscale structures in the Galaxy have been found. Filaments, shells, clouds are entities widely spread in the ISM. In such a highly non-homogeneous (fractal-like) ISM the normal diffusion model certainly is not kept valid. Generalization of this model leads to what is known as "anomalous diffusion". The main goal of the report is to retrieve the cosmic ray injection spectrum at the galactic sources in the framework of the anomalous diffusion (AD) model. The anomaly in this model results from large free paths ("Levy flights") of particles between galactic inhomogeneities. In order to evaluate the CR spectrum at the sources, we carried out new calculation of the CR spectra at Earth. AD equation in terms of fractional derivatives have been used to describe CR propagation from the nearby (r≤1 kpc) young (t≤ 1 Myr) and multiple old distant (r > 1 kpc) sources. The assessment of the key model parameters have been based on the results of the particles diffusion in the cosmic and laboratory plasma. We show that in the framework of the anomalous diffusion model the locally observed basic features of the cosmic rays (difference between spectral exponents of proton, He and other nuclei, "knee" problem, positron to electron ratio) can be explained if the injection spectrum at the main galactic sources of cosmic rays has spectral exponent p˜ 2.85. The authors acknowledge support from The Russian Foundation for Basic Research grant No. 14-02-31524.

  20. Ultra-heavy cosmic rays: Theoretical implications of recent observations

    NASA Technical Reports Server (NTRS)

    Blake, J. B.; Hainebach, K. L.; Schramm, D. N.; Anglin, J. D.

    1977-01-01

    Extreme ultraheavy cosmic ray observations (Z greater or equal 70) are compared with r-process models. A detailed cosmic ray propagation calculation is used to transform the calculated source distributions to those observed at the earth. The r-process production abundances are calculated using different mass formulae and beta-rate formulae; an empirical estimate based on the observed solar system abundances is used also. There is the continued strong indication of an r-process dominance in the extreme ultra-heavy cosmic rays. However it is shown that the observed high actinide/Pt ratio in the cosmic rays cannot be fit with the same r-process calculation which also fits the solar system material. This result suggests that the cosmic rays probably undergo some preferential acceleration in addition to the apparent general enrichment in heavy (r-process) material. As estimate also is made of the expected relative abundance of superheavy elements in the cosmic rays if the anomalous heavy xenon in carbonaceous chondrites is due to a fissioning superheavy element.

  1. Semianalytic calculation of cosmic microwave background anisotropies from wiggly and superconducting cosmic strings

    NASA Astrophysics Data System (ADS)

    Rybak, I. Yu.; Avgoustidis, A.; Martins, C. J. A. P.

    2017-11-01

    We study how the presence of world-sheet currents affects the evolution of cosmic string networks, and their impact on predictions for the cosmic microwave background (CMB) anisotropies generated by these networks. We provide a general description of string networks with currents and explicitly investigate in detail two physically motivated examples: wiggly and superconducting cosmic string networks. By using a modified version of the CMBact code, we show quantitatively how the relevant network parameters in both of these cases influence the predicted CMB signal. Our analysis suggests that previous studies have overestimated the amplitude of the anisotropies for wiggly strings. For superconducting strings the amplitude of the anisotropies depends on parameters which presently are not well known—but which can be measured in future high-resolution numerical simulations.

  2. Smooth halos in the cosmic web

    SciTech Connect

    Gaite, José, E-mail: jose.gaite@upm.es

    Dark matter halos can be defined as smooth distributions of dark matter placed in a non-smooth cosmic web structure. This definition of halos demands a precise definition of smoothness and a characterization of the manner in which the transition from smooth halos to the cosmic web takes place. We introduce entropic measures of smoothness, related to measures of inequality previously used in economy and with the advantage of being connected with standard methods of multifractal analysis already used for characterizing the cosmic web structure in cold dark matter N-body simulations. These entropic measures provide us with a quantitative description ofmore » the transition from the small scales portrayed as a distribution of halos to the larger scales portrayed as a cosmic web and, therefore, allow us to assign definite sizes to halos. However, these ''smoothness sizes'' have no direct relation to the virial radii. Finally, we discuss the influence of N-body discreteness parameters on smoothness.« less

  3. Energetic ion and cosmic ray characteristics of a magnetic cloud

    NASA Astrophysics Data System (ADS)

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

    The large interplanetary shock event of February 11, 1982, has yielded ISEE-3 energetic ion and magnetic field data as well as ground-based neutron-monitor cosmic-ray data. The timing and the onset of the Forbush decrease associated with this shock event coincide with the arrival at the earth of its magnetic cloud component; the duration of the decrease, similarly, corresponds to that of the cloud's passage past the earth. The large scattering mean free path readings suggest that while magnetic cloud ions can easily travel along magnetic field lines, they cannot travel across them, so that they cannot escape the cloud after entering it. Similarly, the cloud field lines prevented cosmic ray entrance, and could have prevented their reaching the earth. The cloud is therefore a major basis for the Forbush decrease.

  4. Neutrinos from cosmic ray interactions in the Sun

    SciTech Connect

    Edsjö, J.; Elevant, J.; Niblaeus, C.

    Cosmic rays hitting the solar atmosphere generate neutrinos that interact and oscillate in the Sun and oscillate on the way to Earth. These neutrinos could potentially be detected with neutrino telescopes and will be a background for searches for neutrinos from dark matter annihilation in the Sun. We calculate the flux of neutrinos from these cosmic ray interactions in the Sun and also investigate the interactions near a detector on Earth that give rise to muons. We compare this background with both regular Earth-atmospheric neutrinos and signals from dark matter annihilation in the Sun. Our calculation is performed with anmore » event-based Monte Carlo approach that should be suitable as a simulation tool for experimental collaborations. Our program package is released publicly along with this paper.« less

  5. PLASMA EFFECTS ON EXTRAGALACTIC ULTRAHIGH-ENERGY COSMIC-RAY HADRON BEAMS IN COSMIC VOIDS. II. KINETIC INSTABILITY OF PARALLEL ELECTROSTATIC WAVES

    SciTech Connect

    Krakau, S.; Schlickeiser, R., E-mail: steffen.krakau@rub.de, E-mail: rsch@tp4.rub.de

    2016-02-20

    The linear instability of an ultrarelativistic hadron beam in the unmagnetized intergalactic medium (IGM) is investigated with respect to the excitation of parallel electrostatic and electromagnetic fluctuations. This analysis is important for the propagation of extragalactic ultrarelativistic cosmic rays from their distant sources to Earth. As opposed to the previous paper, we calculate the minimum instability growth time for Lorentz-distributed cosmic rays which traverse the hot IGM. The growth times are orders of magnitude higher than the cosmic-ray propagation time in the IGM. Since the backreaction of the generated plasma fluctuations (plateauing) lasts longer than the propagation time, the cosmic-raymore » hadron beam can propagate to the Earth without losing a significant amount of energy to electrostatic turbulence.« less

  6. Characterizing an Integrated Annual Global Measure of the Earth's Maximum Land Surface Temperatures from 2003 to 2012 Reveals Strong Biogeographic Influences

    NASA Astrophysics Data System (ADS)

    Mildrexler, D. J.; Zhao, M.; Running, S. W.

    2014-12-01

    Land Surface Temperature (LST) is a good indicator of the surface energy balance because it is determined by interactions and energy fluxes between the atmosphere and the ground. The variability of land surface properties and vegetation densities across the Earth's surface changes these interactions and gives LST a unique biogeographic influence. Natural and human-induced disturbances modify the surface characteristics and alter the expression of LST. This results in a heterogeneous and dynamic thermal environment. Measurements that merge these factors into a single global metric, while maintaining the important biophysical and biogeographical factors of the land surface's thermal environment are needed to better understand integrated temperature changes in the Earth system. Using satellite-based LST we have developed a new global metric that focuses on one critical component of LST that occurs when the relationship between vegetation density and surface temperature is strongly coupled: annual maximum LST (LSTmax). A 10 year evaluation of LSTmax histograms that include every 1-km pixel across the Earth's surface reveals that this integrative measurement is strongly influenced by the biogeographic patterns of the Earth's ecosystems, providing a unique comparative view of the planet every year that can be likened to the Earth's thermal maximum fingerprint. The biogeographical component is controlled by the frequency and distribution of vegetation types across the Earth's land surface and displays a trimodal distribution. The three modes are driven by ice covered polar regions, forests, and hot desert/shrubland environments. In ice covered areas the histograms show that the heat of fusion results in a convergence of surface temperatures around the melting point. The histograms also show low interannual variability reflecting two important global land surface dynamics; 1) only a small fraction of the Earth's surface is disturbed in any given year, and 2) when

  7. The estimation of galactic cosmic ray penetration and dose rates

    NASA Technical Reports Server (NTRS)

    Burrell, M. O.; Wright, J. J.

    1972-01-01

    This study is concerned with approximation methods that can be readily applied to estimate the absorbed dose rate from cosmic rays in rads - tissue or rems inside simple geometries of aluminum. The present work is limited to finding the dose rate at the center of spherical shells or behind plane slabs. The dose rate is calculated at tissue-point detectors or for thin layers of tissue. This study considers cosmic-rays dose rates for both free-space and earth-orbiting missions.

  8. Dark cosmic rays

    DOE PAGES

    Hu, Ping-Kai; Kusenko, Alexander; Takhistov, Volodymyr

    2017-02-22

    If dark matter particles have an electric charge, as in models of millicharged dark matter, such particles should be accelerated in the same astrophysical accelerators that produce ordinary cosmic rays, and their spectra should have a predictable rigidity dependence. Depending on the charge, the resulting “dark cosmic rays” can be detected as muon-like or neutrino-like events in Super-Kamiokande, IceCube, and other detectors. We present new limits and propose several new analyses, in particular, for the Super-Kamiokande experiment, which can probe a previously unexplored portion of the millicharged dark matter parameter space. Here, most of our results are fairly general andmore » apply to a broad class of dark matter models.« less

  9. COSMIC monthly progress report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Activities of the Computer Software Management and Information Center (COSMIC) are summarized for the month of April 1994. Tables showing the current inventory of programs available from COSMIC are presented and program processing and evaluation activities are summarized. Five articles were prepared for publication in the NASA Tech Brief Journal. These articles (included in this report) describe the following software items: GAP 1.0 - Groove Analysis Program, Version 1.0; SUBTRANS - Subband/Transform MATLAB Functions for Image Processing; CSDM - COLD-SAT Dynamic Model; CASRE - Computer Aided Software Reliability Estimation; and XOPPS - OEL Project Planner/Scheduler Tool. Activities in the areas of marketing, customer service, benefits identification, maintenance and support, and disseminations are also described along with a budget summary.

  10. Galactic cosmic ray composition

    NASA Technical Reports Server (NTRS)

    Meyer, J. P.

    1986-01-01

    An assessment is given of the galactic cosmic ray source (GCRS) elemental composition and its correlation with first ionization potential. The isotopic composition of heavy nuclei; spallation cross sections; energy spectra of primary nuclei; electrons; positrons; local galactic reference abundances; comparison of solar energetic particles and solar coronal compositions; the hydrogen; lead; nitrogen; helium; and germanium deficiency problems; and the excess of elements are among the topics covered.

  11. Cosmic Magnetic Fields - An Overview

    NASA Astrophysics Data System (ADS)

    Wielebinski, Richard; Beck, Rainer

    Magnetic fields have been known in antiquity. Aristotle attributes the first of what could be called a scientific discussion on magnetism to Thales, who lived from about 625 BC. In China “magnetic carts” were in use to help the Emperor in his journeys of inspection. Plinius comments that in the Asia Minor province of Magnesia shepherds' staffs get at times “glued” to a stone, a alodestone. In Europe the magnetic compass came through the Arab sailors who met the Portuguese explorers. The first scientific treatise on magnetism, “De Magnete”, was published by William Gilbert who in 1600 described his experiments and suggested that the Earth was a huge magnet. Johannes Kepler was a correspondent of Gilbert and at times suggested that planetary motion was due to magnetic forces. Alas, this concept was demolished by Isaac Newton,who seeing the falling apple decided that gravity was enough. This concept of dealing with gravitational forces only remains en vogue even today. The explanations why magnetic effects must be neglected go from “magnetic energy is only 1% of gravitation” to “magnetic fields only complicate the beautiful computer solutions”. What is disregarded is the fact that magnetic effects are very directional(not omni-directional as gravity) and also the fact that magnetic fields are seen every where in our cosmic universe.

  12. Stars and Cosmic Rays Observed from Mars

    NASA Image and Video Library

    2004-03-12

    In this five-minute exposure taken from the surface of Mars by NASA Spirit rover, stars appear as streaks due to the rotation of the planet, and instantaneous cosmic-ray hits appear as points of light. Spirit took the image with its panoramic camera on March 11, 2004, after waking up during the martian night for a communication session with NASA's Mars Global Surveyor orbiter. Other exposures were also taken. The images tested the capabilities of the rover for night-sky observations. Scientists will use the results to aid planning for possible future astronomical observations from Mars. The difference in Mars' rotation, compared to Earth's, gives the star trails in this image a different orientation than they would have in a comparable exposure taken from Earth. http://photojournal.jpl.nasa.gov/catalog/PIA05551

  13. Cosmic transparency and acceleration

    NASA Astrophysics Data System (ADS)

    Holanda, R. F. L.; Pereira, S. H.; Jain, Deepak

    2018-01-01

    In this paper, by considering an absorption probability independent of photon wavelength, we show that current type Ia supernovae (SNe Ia) and gamma-ray burst (GRB) observations plus high-redshift measurements of the cosmic microwave background (CMB) radiation temperature support cosmic acceleration regardless of the transparent-universe assumption. Two flat scenarios are considered in our analyses: the Λ CDM model and a kinematic model. We consider τ (z )=2 ln (1 +z )ɛ, where τ (z ) denotes the opacity between an observer at z =0 and a source at z . This choice is equivalent to deforming the cosmic distance duality relation as DLDA-1=(1 +z )2+ɛ and, if the absorption probability is independent of photon wavelength, the CMB temperature evolution law is TCMB(z )=T0(1 +z )1+2 ɛ /3. By marginalizing on the ɛ parameter, our analyses rule out a decelerating universe at 99.99% C.L. for all scenarios considered. Interestingly, by considering only SNe Ia and GRBs observations, we obtain that a decelerated universe—indicated by ΩΛ≤0.33 and q0>0 —is ruled out around 1.5 σ C.L. and 2 σ C.L., respectively, regardless of the transparent-universe assumption.

  14. Relativistic heavy cosmic rays

    NASA Technical Reports Server (NTRS)

    Mewaldt, R. A.; Fernandez, J. I.; Israel, M. H.; Klarmann, J.; Binns, W. R.

    1972-01-01

    During three balloon flights of a 1 sq m sr ionization chamber/Cerenkov counter detector system, measurements were made of the atmospheric attenuation, flux, and charge composition of cosmic ray nuclei with 16 is less than or = Z is less than or = 30 and rigidity greater than 4.5 GV. The attenuation mean free path in air of VH (20 less than or = Z less than or = 30) nuclei is found to be 19.7 + or - 1.6 g/sq cm, a value somewhat greater than the best previous measurement. The attenuation mean free path of iron is found to be 15.6 + or - 2.2 g/sq cm, consistent with predictions of geometric cross-section formulae. An absolute flux of VH nuclei 10 to 20% higher than earlier experiments at similar geomagnetic cutoff and level of solar activity was measured. The relative abundances of even-charged nuclei are found to be in good agreement with results of other recent high resolution counter experiments. The observed cosmic ray chemical composition implies relative abundances at the cosmic ray source of Ca/Fe = 0.12 + or - 0.04 and S/Fe = 0.14 + or - 0.05.

  15. Astronomy: A small star with an Earth-like planet

    NASA Astrophysics Data System (ADS)

    Deming, Drake

    2015-11-01

    A rocky planet close in size to Earth has been discovered in the cosmic vicinity of our Sun. The small size and proximity of the associated star bode well for studies of the planet's atmosphere. See Letter p.204

  16. Caustic Skeleton & Cosmic Web

    NASA Astrophysics Data System (ADS)

    Feldbrugge, Job; van de Weygaert, Rien; Hidding, Johan; Feldbrugge, Joost

    2018-05-01

    We present a general formalism for identifying the caustic structure of a dynamically evolving mass distribution, in an arbitrary dimensional space. The identification of caustics in fluids with Hamiltonian dynamics, viewed in Lagrangian space, corresponds to the classification of singularities in Lagrangian catastrophe theory. On the basis of this formalism we develop a theoretical framework for the dynamics of the formation of the cosmic web, and specifically those aspects that characterize its unique nature: its complex topological connectivity and multiscale spinal structure of sheetlike membranes, elongated filaments and compact cluster nodes. Given the collisionless nature of the gravitationally dominant dark matter component in the universe, the presented formalism entails an accurate description of the spatial organization of matter resulting from the gravitationally driven formation of cosmic structure. The present work represents a significant extension of the work by Arnol'd et al. [1], who classified the caustics that develop in one- and two-dimensional systems that evolve according to the Zel'dovich approximation. His seminal work established the defining role of emerging singularities in the formation of nonlinear structures in the universe. At the transition from the linear to nonlinear structure evolution, the first complex features emerge at locations where different fluid elements cross to establish multistream regions. Involving a complex folding of the 6-D sheetlike phase-space distribution, it manifests itself in the appearance of infinite density caustic features. The classification and characterization of these mass element foldings can be encapsulated in caustic conditions on the eigenvalue and eigenvector fields of the deformation tensor field. In this study we introduce an alternative and transparent proof for Lagrangian catastrophe theory. This facilitates the derivation of the caustic conditions for general Lagrangian fluids, with

  17. Intensity of Upward Muon Flux Due to Cosmic-Ray Neutrinos Produced in the Atmosphere

    DOE R&D Accomplishments Database

    Lee, T. D.; Robinson, H.; Schwartz, M.; Cool, R.

    1963-06-01

    Calculations were performed to determine the upward going muon flux leaving the earth's surface after production by cosmic-ray neutrinos in the crust. Only neutrinos produced in the earth's atmosphere are considered. Rates of the order of one per 100 sq m/day might be expected if an intermediate boson exists and has a mass less than 2 Bev. (auth)

  18. Deriving the solar activity cycle modulation on cosmic ray intensity observed by Nagoya muon detector from October 1970 until December 2012

    NASA Astrophysics Data System (ADS)

    de Mendonça, Rafael R. S.; Braga, Carlos. R.; Echer, Ezequiel; Dal Lago, Alisson; Rockenbach, Marlos; Schuch, Nelson J.; Munakata, Kazuoki

    2017-10-01

    It is well known that the cosmic ray intensity observed at the Earth's surface presents an 11 and 22-yr variations associated with the solar activity cycle. However, the observation and analysis of this modulation through ground muon detectors datahave been difficult due to the temperature effect. Furthermore, instrumental changes or temporary problems may difficult the analysis of these variations. In this work, we analyze the cosmic ray intensity observed since October 1970 until December 2012 by the Nagoya muon detector. We show the results obtained after analyzing all discontinuities and gaps present in this data and removing changes not related to natural phenomena. We also show the results found using the mass weighted method for eliminate the influence of atmospheric temperature changes on muon intensity observed at ground. As a preliminary result of our analyses, we show the solar cycle modulation in the muon intensity observed for more than 40 years.

  19. Cosmic strings and galaxy formation

    NASA Technical Reports Server (NTRS)

    Bertschinger, Edmund

    1989-01-01

    The cosmogonical model proposed by Zel'dovich and Vilenkin (1981), in which superconducting cosmic strings act as seeds for the origin of structure in the universe, is discussed, summarizing the results of recent theoretical investigations. Consideration is given to the formation of cosmic strings, the microscopic structure of strings, gravitational effects, cosmic string evolution, and the formation of galaxies and large-scale structure. Simulation results are presented in graphs, and several outstanding issues are listed and briefly characterized.

  20. Cosmic Convergence: Art and Science

    NASA Astrophysics Data System (ADS)

    Mayo, Elizabeth A.; Zisholtz, E.; Hilton, H.

    2010-01-01

    The I.P. Stanback Museum and Planetarium is a major educational and teaching resource for South Carolina State University, K-12 schools, other universities and the community of Orangeburg and well beyond. The concept of creating a museum with a planetarium on the campus of SC State was ahead of its time. Today scholars are writing about the unity of creative disciplines. Through its integration of the arts, humanities and sciences, the Stanback, the only art museum with a planetarium at any of the Historically Black Colleges and Universities and one of the few in the nation, stands in the forefront of modern thinking. Cosmic Convergence: Art and Science, opening at the I.P. Stanback Museum and Planetarium in February 2010, will feature the works of Mildred Thompson (1936-2003), a prominent African American artist who worked in the media of painting, drawing, print making, sculpture, and photography. Thompson’s artwork shows the strong influences of her interest in physics, astronomy, and metaphysics as well as music and spiritualism. “My work in the visual arts is, and has always been, a continuous search for understanding. It is an expression of purpose and reflects a personal interpretation of the Universe.” Cosmic Convergence will explore the meeting of Art and Science through Mildred Thompson's work and the scientific basis of that work. The paintings and sculptures of the exhibit will be combined with astronomical images showing both the reality and interpretation of the surrounding Universe. Support for this work was provided by the NSF PAARE program to South Carolina State University under award AST-0750814.

  1. Neural network and wavelets in prediction of cosmic ray variability: The North Africa as study case

    NASA Astrophysics Data System (ADS)

    Zarrouk, Neïla; Bennaceur, Raouf

    2010-04-01

    Since the Earth is permanently bombarded with energetic cosmic rays particles, cosmic ray flux has been monitored by ground based neutron monitors for decades. In this work an attempt is made to investigate the decomposition and reconstructions provided by Morlet wavelet technique, using data series of cosmic rays variabilities, then to constitute from this wavelet analysis an input data base for the neural network system with which we can then predict decomposition coefficients and all related parameters for other points. Thus the latter are used for the recomposition step in which the plots and curves describing the relative cosmic rays intensities are obtained in any points on the earth in which we do not have any information about cosmic rays intensities. Although neural network associated with wavelets are not frequently used for cosmic rays time series, they seems very suitable and are a good choice to obtain these results. In fact we have succeeded to derive a very useful tool to obtain the decomposition coefficients, the main periods for each point on the Earth and on another hand we have now a kind of virtual NM for these locations like North Africa countries, Maroc, Algeria, Tunisia, Libya and Cairo. We have found the aspect of very known 11-years cycle: T1, we have also revealed the variation type of T2 and especially T3 cycles which seem to be induced by particular Earth's phenomena.

  2. Feasibility of Cosmic-Ray Muon Intensity Measurements for Tunnel Detection

    DTIC Science & Technology

    1990-06-01

    BUR-’TR-3110 TECHNICAL REPORT BRL-TR-3110 mBRL I• FEASIBILITY OF COSMIC - RAY MUON INTENSITY MEASUREMENTS FOR TUNNEL DETECTION AIVARS CELIN. , JUNE...Feasibility of Cosmic - Ray Muon Intensity Measurements f or Tunnel Detection 612786H20001 4.AUTNOR(S) Aivars Celmins 7. PERORMING ORGANIZATION NAMe(S) AND... cosmic - ray muon intensity depends on the amount, of material above the point of reference and is therefore influenced by anomalies in rock density

  3. Cosmic-ray transport in the heliosphere: A global perspective

    NASA Astrophysics Data System (ADS)

    Florinski, Vladimir

    2013-02-01

    Earth is shielded from the hazardous galactic radiation in the form or cosmic ray ions by the outwardly flow of the solar wind plasma and by the geomagnetic field. Understanding the effects of the global structure of the heliosphere on the transport of energetic charged particles remains an important challenge in space physics. The expanding bubble of the supersonic solar wind cools the populations of GeV ions that penetrate deeply into the interplanetary space. Beyond the solar wind lies the heliosheath that is believed to act as a long-term storage reservoir for the cosmic rays. The heliosheath and its magnetic field topology play an important role in modulating cosmic rays at large heliocentric distances. Understanding this role is crucial for interpreting the the puzzling Voyager spacecraft observations near the edge of the solar system.

  4. Cosmic-Ray Energetics and Mass Processing - Bonding

    NASA Image and Video Library

    2017-06-20

    Research that started aboard balloons a century ago will soon culminate in a three-year stint aboard the International Space Station as scientists work on solving a fundamental astrophysics mystery: What gives cosmic rays such incredible energies, and how does that affect the composition of the universe? The Cosmic-Ray Energetics and Mass investigation, known as CREAM, places a highly successful balloon-borne instrument aboard the International Space Station where it gathers an order of magnitude (ten times) more data, which has lower background interference because Earth's atmosphere is no longer interfering. CREAM's instruments measure the charges of cosmic rays ranging from hydrogen up through iron nuclei, over a broad energy range. The modified balloon instrument is carried aloft on a SpaceX Dragon Lab cargo supply mission and placed on the Japanese Exposed Module for a period of at least three years.

  5. Cosmic-Ray Energetics and Mass Processing - Unbagging and Inspection

    NASA Image and Video Library

    2017-06-22

    Research that started aboard balloons a century ago will soon culminate in a three-year stint aboard the International Space Station as scientists work on solving a fundamental astrophysics mystery: What gives cosmic rays such incredible energies, and how does that affect the composition of the universe? The Cosmic-Ray Energetics and Mass investigation, known as CREAM, places a highly successful balloon-borne instrument aboard the International Space Station where it gathers an order of magnitude (ten times) more data, which has lower background interference because Earth's atmosphere is no longer interfering. CREAM's instruments measure the charges of cosmic rays ranging from hydrogen up through iron nuclei, over a broad energy range. The modified balloon instrument is carried aloft on a SpaceX Dragon Lab cargo supply mission and placed on the Japanese Exposed Module for a period of at least three years.

  6. Determination and study of the cosmic-ray composition above 100 TeV

    SciTech Connect

    Sinnis, G.; Haines, T.J.; Hoffman, C.M.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of this project was to develop a new technique using ground-based measurements to determine the cosmic-ray composition at energies around 10{sup 15} eV (the knee in the cosmic-ray spectrum). Cosmic rays are high-energy nuclei that continuously bombard the earth. Though cosmic rays were first detected in the 1870s it wasn`t until 1915 that their cosmic origin was established. At present, the authors still do not know the source of cosmic rays. At energies above 50 TeVmore » (1 TeV = 1 trillion electron-volts) they do not know the composition of the cosmic rays. At about 5 PeV (1PeV = 10{sup 15} eV) the cosmic ray spectrum steepens. Knowledge of the composition above and below this point can help determine the origin of cosmic rays.« less

  7. Toward a Cosmic Dawn Mapper

    NASA Astrophysics Data System (ADS)

    Bowman, Judd D.

    2018-06-01

    After stars formed in the early universe, their ultraviolet light altered the 21cm hyperfine state of hydrogen atoms, causing the atoms to absorb photons from the cosmic microwave background. The EDGES experiment has reported evidence for this signal as a decrease in the sky-averaged radio intensity observed today as a broad feature centered at 78 MHz due to cosmological redshift, corresponding to an age of about 200 million years after the Big Bang. Ground-based radio arrays are expected soon to detect and eventually to characterize the power spectrum of spatial fluctuations of the 21cm absorption signal. However, the Earth’s ionosphere and radio transmitters, particularly those in the FM radio band, will complicate the observations and likely will limit the ultimate goal of imaging the era of cosmic dawn in detail. A radio array in lunar orbit or on the lunar suface would avoid the limitations imposed by Earth ionosphere’s. The Moon’s farside is also uniquely shielded from human-generated radio interference. Locating the radio observatory on the lunar surface compared to orbit has potential advantages, including fixed locations for the antennas that require no propulsion to maintain and simpler operations. The lunar surface poses unique challenges for instruments, including surviving the 14-day lunar night when there is no sunlight and temperatures can fall to 100 K. Building on lessons from ground based arrays and design studies from the last decade that led to the Dark Ages Lunar Interferometer and the Lunar Array for Radio Cosmology concepts, we are exploring a trade space for key lunar array technology. Our trade space includes choices related to: 1) antenna design for optimizing sensitivity and mass, while maintaining mechanical and thermal stability and enabling cost-effective deployment scenarios; 2) location of the array on the lunar surface to provide an efficient observing paradigm and suitable environmental conditions; 3) data transportation and

  8. COSMIC DUST AGGREGATION WITH STOCHASTIC CHARGING

    SciTech Connect

    Matthews, Lorin S.; Hyde, Truell W.; Shotorban, Babak, E-mail: Lorin_Matthews@baylor.edu

    2013-10-20

    The coagulation of cosmic dust grains is a fundamental process which takes place in astrophysical environments, such as presolar nebulae and circumstellar and protoplanetary disks. Cosmic dust grains can become charged through interaction with their plasma environment or other processes, and the resultant electrostatic force between dust grains can strongly affect their coagulation rate. Since ions and electrons are collected on the surface of the dust grain at random time intervals, the electrical charge of a dust grain experiences stochastic fluctuations. In this study, a set of stochastic differential equations is developed to model these fluctuations over the surface ofmore » an irregularly shaped aggregate. Then, employing the data produced, the influence of the charge fluctuations on the coagulation process and the physical characteristics of the aggregates formed is examined. It is shown that dust with small charges (due to the small size of the dust grains or a tenuous plasma environment) is affected most strongly.« less

  9. Cosmic Dawn with WFIRST

    NASA Astrophysics Data System (ADS)

    Rhoads, James

    Central objectives: WFIRST-AFTA has tremendous potential for studying the epoch of "Cosmic Dawn" the period encompassing the formation of the first galaxies and quasars, and their impact on the surrounding universe through cosmological reionization. Our goal is to ensure that this potential is realized through the middle stages of mission planning, culminating in designs for both WFIRST and its core surveys that meet the core objectives in dark energy and exoplanet science, while maximizing the complementary Cosmic Dawn science. Methods: We will consider a combined approach to studying Cosmic Dawn using a judicious mixture of guest investigator data analysis of the primary WFIRST surveys, and a specifically designed Guest Observer program to complement those surveys. The Guest Observer program will serve primarily to obtain deep field observations, with particular attention to the capabilities of WFIRST for spectroscopic deep fields using the WFI grism. We will bring to bear our years of experience with slitless spectroscopy on the Hubble Space Telescope, along with an expectation of JWST slitless grism spectroscopy. We will use this experience to examine the implications of WFIRST’s grism resolution and wavelength coverage for deep field observations, and if appropriate, to suggest potential modifications of these parameters to optimize the science return on WFIRST. We have assembled a team of experts specializing in (1) Lyman Break Galaxies at redshifts higher than 7 (2) Quasars at high redshifts (3) Lyman-alpha galaxies as probes of reionization (4) Theoretical simulations of high-redshift galaxies (5) Simulations of grism observations (6) post-processing analysis to find emission line galaxies and high redshift galaxies (7) JWST observations and calibrations. With this team we intend to do end-to-end simulations starting with halo populations and expected spectra of high redshift galaxies and finally extracting what we can learn about (a) reionization

  10. CosmicSIG science and plans

    NASA Astrophysics Data System (ADS)

    Olinto, Angela V.

    2014-03-01

    Recent activities of the Cosmic Ray Science Interest Group (CosmicSIG) of the Physics of the Cosmos PAG will be reviewed. CosmicSIG was formed to provide an assessment to NASA HQ and the PCOS program office of the status of current and future missions in the area of cosmic-ray astrophysics. CosmicSIG also strives to act as a focal point and forum for the cosmic ray community.

  11. Cosmological cosmic strings

    NASA Technical Reports Server (NTRS)

    Gregory, Ruth

    1988-01-01

    The effect of an infinite cosmic string on a cosmological background is investigated. It is found that the metric is approximately a scaled version of the empty space string metric, i.e., conical in nature. Results are used to place bounds on the amount of cylindrical gravitational radiation currently emitted by such a string. The gravitational radiation equations are then analyzed explicitly and it is shown that even initially large disturbances are rapidly damped as the expansion proceeds. The implications of the gravitational radiation background and the limitations of the quadrupole formula are discussed.

  12. The Cosmic Background Explorer

    NASA Technical Reports Server (NTRS)

    Gulkis, Samuel; Lubin, Philip M.; Meyer, Stephan S.; Silverberg, Robert F.

    1990-01-01

    The Cosmic Background Explorer (CBE), NASA's cosmological satellite which will observe a radiative relic of the big bang, is discussed. The major questions connected to the big bang theory which may be clarified using the CBE are reviewed. The satellite instruments and experiments are described, including the Differential Microwave Radiometer, which measures the difference between microwave radiation emitted from two points on the sky, the Far-Infrared Absolute Spectrophotometer, which compares the spectrum of radiation from the sky at wavelengths from 100 microns to one cm with that from an internal blackbody, and the Diffuse Infrared Background Experiment, which searches for the radiation from the earliest generation of stars.

  13. The cosmic microwave background

    NASA Technical Reports Server (NTRS)

    Silk, Joseph

    1991-01-01

    Recent limits on spectral distortions and angular anisotropies in the cosmic microwave background are reviewed. The various backgrounds are described, and the theoretical implications are assessed. Constraints on inflationary cosmology dominated by cold dark matter (CDM) and on open cosmological models dominated by baryonic dark matter (BDM), with, respectively, primordial random phase scale-invariant curvature fluctuations or non-gaussian isocurvature fluctuations are described. More exotic theories are addressed, and I conclude with the 'bottom line': what theorists expect experimentalists to be measuring within the next two to three years without having to abandon their most cherished theories.

  14. Tracing Cosmic Dawn

    NASA Astrophysics Data System (ADS)

    Fialkov, Anastasia

    2018-05-01

    Observational effort is on the way to probe the 21-cm of neutral hydrogen from the epochs of Reionization and Cosmic Dawn. Our current poor knowledge of high redshift astrophysics results in a large uncertainty in the theoretically predicted 21-cm signal. A recent parameter study that is highlighted here explores the variety of 21-cm signals resulting from viable astrophysical scenarios. Model-independent relations between the shape of the signal and the underlying astrophysics are discussed. Finally, I briefly note on possible alternative probes of the high redshift Universe, specifically Fast Radio Bursts.

  15. Detection of low tension cosmic superstrings

    NASA Astrophysics Data System (ADS)

    Chernoff, David F.; Tye, S.-H. Henry

    2018-05-01

    Cosmic superstrings of string theory differ from conventional cosmic strings of field theory. We review how the physical and cosmological properties of the macroscopic string loops influence experimental searches for these relics from the epoch of inflation. The universe's average density of cosmic superstrings can easily exceed that of conventional cosmic strings having the same tension by two or more orders of magnitude. The cosmological behavior of the remnant superstring loops is qualitatively distinct because the string tension is exponentially smaller than the string scale in flux compactifications in string theory. Low tension superstring loops live longer, experience less recoil (rocket effect from the emission of gravitational radiation) and tend to cluster like dark matter in galaxies. Clustering enhances the string loop density with respect to the cosmological average in collapsed structures in the universe. The enhancement at the Sun's position is ~ 105. We develop a model encapsulating the leading order string theory effects, the current understanding of the string network loop production and the influence of cosmological structure formation suitable for forecasting the detection of superstring loops via optical microlensing, gravitational wave bursts and fast radio bursts. We evaluate the detection rate of bursts from cusps and kinks by LIGO- and LISA-like experiments. Clustering dominates rates for G μ < 10‑11.9 (LIGO cusp), G μ<10‑11.2 (LISA cusp), G μ < 10‑10.6 (LISA kink); we forecast experimentally accessible gravitational wave bursts for G μ>10‑14.2 (LIGO cusp), G μ>10‑15 (LISA cusp) and G μ>10‑ 14.1 (LISA kink).

  16. Critical decisions on Cosmic Vision

    NASA Astrophysics Data System (ADS)

    2003-11-01

    Eddington had two aims, both remarkable and very pertinent to front-line astronomical interests. The first was to look for Earth-like planets outside our solar system - one of the key goals in the search to understand how life came to be, how it is that we live where we do in the universe and whether there are other potential life-supporting environments 'out there'. At the same time it was going to follow the path that the ESA-NASA mission SOHO had taken with the Sun of using astroseismology to look 'inside' stars. In the longer term, the loss of this one mission will not stop ESA and the scientific community pursuing the grand quests to which it would have contributed. The loss of the BepiColombo lander is also hard to take scientifically. ESA, in conjunction with the Japanese space agency, JAXA, will still put two orbiters around Mercury but the ‘ground truth’ provided by the lander is a big loss. However, to land on a planet so near the Sun is no small matter and was a bridge too far in present circumstances, and this chance for Europe to be first has probably been lost. The origins of the problems were recognised at the ESA Council meeting held in June. Several sudden demands on finance occurred in the spring, the most obvious and public being the unforeseen Ariane 5 grounding in January, delaying the launches of Rosetta and Smart-1. A temporary loan of EUR 100 million was granted, but must be paid back out of present resources by the end of 2006. ESA's SPC was therefore caught in a vice. Immediate mission starts had to be severely limited and the overall envelope of the programme contained. With this week’s decisions, the SPC has brought the scope of the Cosmic Vision programme down to a level that necessarily reflects the financial conditions rather than the ambitions of the scientific community. A long and painful discussion during the SPC meeting resulted in the conclusion that only one new mission can be started at this time, namely LISA Pathfinder

  17. A contrastive study on the influences of radial and three-dimensional satellite gravity gradiometry on the accuracy of the Earth's gravitational field recovery

    NASA Astrophysics Data System (ADS)

    Zheng, Wei; Hsu, Hou-Tse; Zhong, Min; Yun, Mei-Juan

    2012-10-01

    The accuracy of the Earth's gravitational field measured from the gravity field and steady-state ocean circulation explorer (GOCE), up to 250 degrees, influenced by the radial gravity gradient Vzz and three-dimensional gravity gradient Vij from the satellite gravity gradiometry (SGG) are contrastively demonstrated based on the analytical error model and numerical simulation, respectively. Firstly, the new analytical error model of the cumulative geoid height, influenced by the radial gravity gradient Vzz and three-dimensional gravity gradient Vij are established, respectively. In 250 degrees, the GOCE cumulative geoid height error measured by the radial gravity gradient Vzz is about 2½ times higher than that measured by the three-dimensional gravity gradient Vij. Secondly, the Earth's gravitational field from GOCE completely up to 250 degrees is recovered using the radial gravity gradient Vzz and three-dimensional gravity gradient Vij by numerical simulation, respectively. The study results show that when the measurement error of the gravity gradient is 3 × 10-12/s2, the cumulative geoid height errors using the radial gravity gradient Vzz and three-dimensional gravity gradient Vij are 12.319 cm and 9.295 cm at 250 degrees, respectively. The accuracy of the cumulative geoid height using the three-dimensional gravity gradient Vij is improved by 30%-40% on average compared with that using the radial gravity gradient Vzz in 250 degrees. Finally, by mutual verification of the analytical error model and numerical simulation, the orders of magnitude from the accuracies of the Earth's gravitational field recovery make no substantial differences based on the radial and three-dimensional gravity gradients, respectively. Therefore, it is feasible to develop in advance a radial cold-atom interferometric gradiometer with a measurement accuracy of 10-13/s2-10-15/s2 for precisely producing the next-generation GOCE Follow-On Earth gravity field model with a high spatial

  18. On the size and velocity distribution of cosmic dust particles entering the atmosphere

    PubMed Central

    Carrillo‐Sánchez, J. D.; Feng, W.; Nesvorný, D.; Janches, D.

    2015-01-01

    Abstract The size and velocity distribution of cosmic dust particles entering the Earth's atmosphere is uncertain. Here we show that the relative concentrations of metal atoms in the upper mesosphere, and the surface accretion rate of cosmic spherules, provide sensitive probes of this distribution. Three cosmic dust models are selected as case studies: two are astronomical models, the first constrained by infrared observations of the Zodiacal Dust Cloud and the second by radar observations of meteor head echoes; the third model is based on measurements made with a spaceborne dust detector. For each model, a Monte Carlo sampling method combined with a chemical ablation model is used to predict the ablation rates of Na, K, Fe, Mg, and Ca above 60 km and cosmic spherule production rate. It appears that a significant fraction of the cosmic dust consists of small (<5 µg) and slow (<15 km s−1) particles. PMID:27478282

  19. Life as a Cosmic Phenomenon: 2. the Panspermic Trajectory of Homo Sapiens

    NASA Astrophysics Data System (ADS)

    Tokoro, Gensuke; Wickramasinghe, N. Chandra

    We discuss the origin and evolution of Homo sapiens in a cosmic context, and in relation to the Hoyle-Wickramasinghe theory of panspermia for which there is now overwhelming evidence. It is argued that the first bacteria (archea) incident on the Earth via the agency of comets 3.8-4 billion years ago continued at later times to be augmented by viral genes (DNA, RNA) from space that eventually led to the evolutionary patterns we see in present-day biology. We argue that the current evolutionary status of Homo sapiens as well as its future trajectory is circumscribed by evolutionary processes that were pre-determined on a cosmic scale -- over vast distances and enormous spans of cosmic time. Based on this teleological hypothesis we postulate that two distinct classes of cosmic viruses (cosmic viral genes) are involved in accounting for the facts relating to the evolution of life.

  20. Cosmic ray physics in space: the role of Sergey Vernov's scientific school

    NASA Astrophysics Data System (ADS)

    Panasyuk, M. I.

    2011-04-01

    Cosmic rays were discovered almost 100 years ago. Since then the scientific world has learned a lot from their nature: the particles nascent in the Universe, both in our Galaxy and outside, the basic mechanisms of their acceleration, transfer in the interstellar environment and the interaction of the primary cosmic rays with the atmosphere surrounding the Earth. Before 1957, i.e., the beginning of the Space Era, researchers' capabilities were limited to experiments performed on the ground, underground and in near-ground atmosphere to flight altitudes of aerostats, airplanes and rockets, i.e., where only secondary radiation is in existence, this is the result of the interaction of cosmic rays with the Earth's atmosphere. The launching of spacecraft allowed the scientists to commence exploring the Universe's primordial matter itself outside the atmosphere, i.e., the primary cosmic rays. Sergey Vernov, the Russian scientist, was among them.

  1. Space-atmospheric interactions of energetic cosmic rays

    NASA Astrophysics Data System (ADS)

    Isar, Paula Gina

    2015-02-01

    Ultra-high energy cosmic rays are the most energetic particles in the Universe of which origin still remain a mystery since a century from their descovery. They are unique messengers coming from far beyond our Milky Way Galaxy, which provides insights into the fundamental matter, energy, space and time. As subatomic particles flying through space to nearly light speed, the ultra-high energy cosmic rays are so rare that they strike the Earth's atmosphere at a rate of up to only one particle per square kilometer per year or century. While the atmosphere is used as a giant calorimeter where cosmic rays induced air showers are initiated and the medium through which Cherenkov or fluorescence light or radio waves propagate, all cosmic ray measurements (performed either from space or ground) rely on an accurate atmospheric monitoring and understanding of atmospheric effects. The interdisciplinary link between Astroparticle Physics and Atmospheric Environment through the ultra-high energy comic rays space - atmospheric interactions, based on the present ground- and future space-based cosmic ray observatories, will be presented.

  2. Cosmic ray propagation and containment

    NASA Technical Reports Server (NTRS)

    Parker, E. N.

    1976-01-01

    The cosmic rays, an active gaseous component of the disk of the galaxy, are considered along with their propagation and containment as a part of the general dynamics of the disk. The sources of cosmic rays are a matter of speculation. The disk is inflated by the cosmic ray gas pressure comparable to the magnetic pressure, but the rate of inflation is unknown. The time spent by the individual cosmic ray particles in the disk is inversely proportional to the cosmic ray production rate. It is evident from the decay of Be(1c) that the cosmic rays circulate through a volume of space perhaps ten times the thickness of the gaseous disk, suggesting a magnetic halo extending out approximately 1 kpc from either face of the disk. The cosmic rays may be responsible for the halo by inflating the magnetic fields of the disk. Extension of the fields to 1 kpc would imply a high production rate and short life of cosmic rays in the dense gaseous disk of the galaxy.

  3. Testing Galactic Cosmic Ray Models

    NASA Technical Reports Server (NTRS)

    Adams, James H., Jr.

    2009-01-01

    Models of the Galactic Cosmic Ray Environment are used for designing and planning space missions. The existing models will be reviewed. Spectral representations from these models will be compared with measurements of galactic cosmic ray spectra made on balloon flights and satellite flights over a period of more than 50 years.

  4. Testing Galactic Cosmic Ray Models

    NASA Technical Reports Server (NTRS)

    Adams, James H., Jr.

    2010-01-01

    Models of the Galactic Cosmic Ray Environment are used for designing and planning space missions. The exising models will be reviewed. Spectral representations from these models will be compared with measurements of galactic cosmic ray spectra made on balloon flights and satellite flights over a period of more than 50 years.

  5. Stable laws and cosmic ray physics

    NASA Astrophysics Data System (ADS)

    Genolini, Y.; Salati, P.; Serpico, P. D.; Taillet, R.

    2017-04-01

    Context. In the new "precision era" for cosmic ray astrophysics, scientists making theoretical predictions cannot content themselves with average trends, but need to correctly take into account intrinsic uncertainties. The space-time discreteness of the cosmic ray sources, together with a substantial ignorance of their precise epochs and locations (with the possible exception of the most recent and close ones) play an important role in this sense. Aims: We elaborate a statistical theory to deal with this problem, relating the composite probability P(Ψ) to obtain a flux Ψ at the Earth and the single-source probability p(ψ) to contribute with a flux ψ. The main difficulty arises from the fact that p(ψ) is a "heavy tail" distribution, characterized by power-law or broken power-law behavior up to very large fluxes, for which the central limit theorem does not hold, and leading to distributions different from Gaussian. The functional form of the distribution for the aggregated flux is nonetheless unchanged by its own convolution, that is, it belongs to the so-called stable laws class. Methods: We analytically discuss the regime of validity of the stable laws associated with the distributions arising in cosmic ray astrophysics, as well as the limitations to the treatment imposed by causal considerations and partial source catalog knowledge. We validate our results with extensive Monte Carlo simulations, for different regimes of propagation parameters and energies. Results: We find that relatively simple recipes provide a satisfactory description of the probability P(Ψ). We also find that a naive Gaussian fit to simulation results would underestimate the probability of very large fluxes, that is, several times above the average, while overestimating the probability of relatively milder excursions. At large energies, large flux fluctuations are prevented by causal considerations, while at low energies, a partial knowledge of the recent and nearby population of

  6. Genuine cosmic hair

    NASA Astrophysics Data System (ADS)

    Kastor, David; Ray, Sourya; Traschen, Jennie

    2017-02-01

    We show that asymptotically future de Sitter (AFdS) spacetimes carry ‘genuine’ cosmic hair; information that is analogous to the mass and angular momentum of asymptotically flat spacetimes and that characterizes how an AFdS spacetime approaches its asymptotic form. We define new ‘cosmological tension’ charges associated with future asymptotic spatial translation symmetries, which are analytic continuations of the ADM mass and tensions of asymptotically planar AdS spacetimes, and which measure the leading anisotropic corrections to the isotropic, exponential de Sitter expansion rate. A cosmological Smarr relation, holding for AFdS spacetimes having exact spatial translation symmetry, is derived. This formula relates cosmological tension, which is evaluated at future infinity, to properties of the cosmology at early times, together with a ‘cosmological volume’ contribution that is analogous to the thermodynamic volume of AdS black holes. Smarr relations for different spatial directions imply that the difference in expansion rates between two directions at late times is related in a simple way to their difference at early times. Hence information about the very early universe can be inferred from cosmic hair, which is potentially observable in a late time de Sitter phase. Cosmological tension charges and related quantities are evaluated for Kasner-de Sitter spacetimes, which serve as our primary examples.

  7. Testing Cosmic Inflation

    NASA Technical Reports Server (NTRS)

    Chuss, David

    2010-01-01

    The Cosmic Microwave Background (CMB) has provided a wealth of information about the history and physics of the early Universe. Much progress has been made on uncovering the emerging Standard Model of Cosmology by such experiments as COBE and WMAP, and ESA's Planck Surveyor will likely increase our knowledge even more. Despite the success of this model, mysteries remain. Currently understood physics does not offer a compelling explanation for the homogeneity, flatness, and the origin of structure in the Universe. Cosmic Inflation, a brief epoch of exponential expansion, has been posted to explain these observations. If inflation is a reality, it is expected to produce a background spectrum of gravitational waves that will leave a small polarized imprint on the CMB. Discovery of this signal would give the first direct evidence for inflation and provide a window into physics at scales beyond those accessible to terrestrial particle accelerators. I will briefly review aspects of the Standard Model of Cosmology and discuss our current efforts to design and deploy experiments to measure the polarization of the CMB with the precision required to test inflation.

  8. COSMIC monthly progress report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Activities of the Computer Software Management and Information Center (COSMIC) are summarized for the month of May 1994. Tables showing the current inventory of programs available from COSMIC are presented and program processing and evaluation activities are summarized. Nine articles were prepared for publication in the NASA Tech Brief Journal. These articles (included in this report) describe the following software items: (1) WFI - Windowing System for Test and Simulation; (2) HZETRN - A Free Space Radiation Transport and Shielding Program; (3) COMGEN-BEM - Composite Model Generation-Boundary Element Method; (4) IDDS - Interactive Data Display System; (5) CET93/PC - Chemical Equilibrium with Transport Properties, 1993; (6) SDVIC - Sub-pixel Digital Video Image Correlation; (7) TRASYS - Thermal Radiation Analyzer System (HP9000 Series 700/800 Version without NASADIG); (8) NASADIG - NASA Device Independent Graphics Library, Version 6.0 (VAX VMS Version); and (9) NASADIG - NASA Device Independent Graphics Library, Version 6.0 (UNIX Version). Activities in the areas of marketing, customer service, benefits identification, maintenance and support, and dissemination are also described along with a budget summary.

  9. COSMIC monthly progress report

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Activities of the Computer Software Management and Information Center (COSMIC) are summarized for the month of August, 1993. Tables showing the current inventory of programs available from COSMIC are presented and program processing and evaluation activities are discussed. Ten articles were prepared for publication in the NASA Tech Brief Journal. These articles (included in this report) describe the following software items: (1) MOM3D - A Method of Moments Code for Electromagnetic Scattering (UNIX Version); (2) EM-Animate - Computer Program for Displaying and Animating the Steady-State Time-Harmonic Electromagnetic Near Field and Surface-Current Solutions; (3) MOM3D - A Method of Moments Code for Electromagnetic Scattering (IBM PC Version); (4) M414 - MIL-STD-414 Variable Sampling Procedures Computer Program; (5) MEDOF - Minimum Euclidean Distance Optimal Filter; (6) CLIPS 6.0 - C Language Integrated Production System, Version 6.0 (Macintosh Version); (7) CLIPS 6.0 - C Language Integrated Production System, Version 6.0 (IBM PC Version); (8) CLIPS 6.0 - C Language Integrated Production System, Version 6.0 (UNIX Version); (9) CLIPS 6.0 - C Language Integrated Production System, Version 6.0 (DEC VAX VMS Version); and (10) TFSSRA - Thick Frequency Selective Surface with Rectangular Apertures. Activities in the areas of marketing, customer service, benefits identification, maintenance and support, and dissemination are also described along with a budget summary.

  10. Wind Observations of Anomalous Cosmic Rays from Solar Minimum to Maximum

    NASA Technical Reports Server (NTRS)

    Reames, D. V.; McDonald, F. B.

    2003-01-01

    We report the first observation near Earth of the time behavior of anomalous cosmic-ray N, O, and Ne ions through the period surrounding the maximum of the solar cycle. These observations were made by the Wind spacecraft during the 1995-2002 period spanning times from solar minimum through solar maximum. Comparison of anomalous and galactic cosmic rays provides a powerful tool for the study of the physics of solar modulation throughout the solar cycle.

  11. Difference between even and odd 11-year cycles in cosmic ray intensity

    NASA Technical Reports Server (NTRS)

    Otaola, J. A.; Perez-Enriquez, R.; Valdes-Galicia, J. F.

    1985-01-01

    Cosmic ray data for the period 1946-1984 are used to determine the run of the cosmic ray intensity over three complete solar cycles. The analysis shows a tendency towards a regular alternation of cosmic ray intensity cycles with double and single maxima. Whereas a saddle-like shape is characteristic of even cycles, odd cycles are characterized by a peak-like shape. The importance of this behavior is discussed in terms of different processes influencing cosmic ray transport in the heliosphere.

  12. Cosmic Dust Collection Facility: Scientific objectives and programmatic relations

    NASA Technical Reports Server (NTRS)

    Hoerz, Fred (Editor); Brownlee, D. E.; Bunch, T. E.; Grounds, D.; Grun, E.; Rummel, Y.; Quaide, W. L.; Walker, R. M.

    1990-01-01

    The science objectives are summarized for the Cosmic Dust Collection Facility (CDCF) on Space Station Freedom and these objectives are related to ongoing science programs and mission planning within NASA. The purpose is to illustrate the potential of the CDCF project within the broad context of early solar system sciences that emphasize the study of primitive objects in state-of-the-art analytical and experimental laboratories on Earth. Current knowledge about the sources of cosmic dust and their associated orbital dynamics is examined, and the results are reviewed of modern microanalytical investigations of extraterrestrial dust particles collected on Earth. Major areas of scientific inquiry and uncertainty are identified and it is shown how CDCF will contribute to their solution. General facility and instrument concepts that need to be pursued are introduced, and the major development tasks that are needed to attain the scientific objectives of the CDCF project are identified.

  13. The Galactic Magnetic Field and Ultra-High Energy Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Urban, Federico R.

    The Galactic Magnetic Field is a peeving and importune screen between Ultra-High Energy Cosmic Rays and us cosmologists, engaged in the combat to unveil their properties and origin, as it deviates their paths towards the Earth in unpredictable ways. I will, in this order: briefly review the available field models on the market; explain a little trick which allows one to obtain cosmic rays deflection variances without even knowing what the (random) GMF model is; and argue that there is a lack of anisotropy in the large scales cosmic rays signal, which the Galactic field can do nothing about.

  14. Microanalytical study of some cosmic dust discovered in sea-floor sediments in China

    NASA Technical Reports Server (NTRS)

    Shijie, Z.; Hanchang, P.; Zhong, Y.

    1984-01-01

    The study of cosmic dust can provide useful data in the investigation of the origin of the Earth and the evolution of celestial bodies. Three types of cosmic dust (ferriginous, siliceous, and glassy) were discovered in the seafloor sediments near China. Their chemical composition and microstructure were examined by X-ray diffraction, fractography, and electron microscopy. The major mineral in an iron-containing cosmic dust is magnetite. The silicate spheres contain sundry metals and metal oxides. Glassy microtektites are similar in composition to tektites, and are found in all the major meteorite areas worldwide.

  15. Influence of soil characteristics on rare earth fingerprints in mosses and mushrooms: Example of a pristine temperate rainforest (Slavonia, Croatia).

    PubMed

    Fiket, Željka; Medunić, Gordana; Furdek Turk, Martina; Ivanić, Maja; Kniewald, Goran

    2017-07-01

    The present study aims to investigate levels and distribution of rare earth elements (REE) in soils, mosses and mushrooms of a pristine temperate rainforest, a non-polluted natural system, in order to characterise their environmental availability and mobility. The multielement analysis of digested soil, moss and mushroom samples was performed by High Resolution Inductively Coupled Plasma Mass Spectrometry. The distribution of rare earths in mosses and mushrooms was found primarily affected by local pedological setting. Mosses displayed a consistent lithological signature with an almost insignificant REE fractionation compared to soils. Mushrooms showed differences in REE concentrations in certain parts of the fruiting body with regard to their main physiological function and indicated a significant impact of soil organic content on the overall REEs uptake. Results of our work highlight the importance of substrate characteristics on the initial levels of REEs in mosses and mushrooms. Moreover, this study provides baseline data on the rare earth element levels in mosses and mushrooms growing in a pristine forest area characterised by naturally elevated REE levels in the soil. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Cosmic Dawn Science Interest Group

    NASA Astrophysics Data System (ADS)

    Lazio, T. Joseph W.; Cosmic Origins Program Analysis Group

    2016-01-01

    Cosmic Dawn was identified as one of the three science objectives for this decade in the _New Worlds, New Horizons_ Decadal report, and it will likely continue to be a research focus well into the next decade. Cosmic Dawn refers to the interval during which the Universe transitioned from a nearly completely neutral state back to a nearly fully ionized state and includes the time during which the first stars formed and the first galaxies assembled.The Cosmic Dawn Science Interest Group (SIG) was formed recently under the auspices of the Cosmic Origins Program Analysis Group (COPAG). The Cosmic Dawn SIG focusses on the science cases, observations, and technology development needed to address the "great mystery" of Cosmic Origins. The reach of this SIG is broad, involving the nature of the first stars and the detectability of gamma-ray bursts at high redshifts, the extent to which the first galaxies and first supermassive black holes grew together, and the technology required to pursue these questions.For further information, consult the Cosmic Dawn SIG Web site http://cd-sig.jpl.nasa.gov/ and join the mailing list (by contacting the author).Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  17. Radioresistance of Adenine to Cosmic Rays.

    PubMed

    Vignoli Muniz, Gabriel S; Mejía, Christian F; Martinez, Rafael; Auge, Basile; Rothard, Hermann; Domaracka, Alicja; Boduch, Philippe

    2017-04-01

    The presence of nucleobases in carbonaceous meteorites on Earth is an indication of the existence of this class of molecules in outer space. However, space is permeated by ionizing radiation, which can have damaging effects on these molecules. Adenine is a purine nucleobase that amalgamates important biomolecules such as DNA, RNA, and ATP. Adenine has a unique importance in biochemistry and therefore life. The aim of this work was to study the effects of cosmic ray analogues on solid adenine and estimate its survival when exposed to corpuscular radiation. Adenine films were irradiated at GANIL (Caen, France) and GSI (Darmstadt, Germany) by 820 MeV Kr 33+ , 190 MeV Ca 10+ , 92 MeV Xe 23+ , and 12 MeV C 4+ ion beams at low temperature. The evolution of adenine molecules under heavy ion irradiation was studied by IR absorption spectroscopy as a function of projectile fluence. It was found that the adenine destruction cross section (σ d ) follows an electronic stopping power (S e ) power law under the form: CS e n ; C is a constant, and the exponential n is a dimensionless quantity. Using the equation above to fit our results, we determined σ d  = 4 × 10 -17 S e 1.17 , with S e in kiloelectronvolts per micrometer (keV μm -1 ). New IR absorption bands arise under irradiation of adenine and can be attributed to HCN, CN - , C 2 H 4 N 4 , CH 3 CN, and (CH 3 ) 3 CNC. These findings may help to understand the stability and chemistry related to complex organic molecules in space. The half-life of solid adenine exposed to the simulated interstellar medium cosmic ray flux was estimated as (10 ± 8) × 10 6 years. Key Words: Heavy ions-Infrared spectroscopy-Astrochemistry-Cosmic rays-Nucleobases-Adenine. Astrobiology 17, 298-308.

  18. Cosmic Light EDU kit

    NASA Astrophysics Data System (ADS)

    Doran, Rosa

    2015-08-01

    In 2015 we celebrate the International Year of Light, a great opportunity to promote awareness about the importance of light coming from the Cosmos and what messages it is bringing to mankind. In parallel a unique moment to attract the attention of stakeholders on the dangers of light pollution and its impact in our lives and our pursuit of more knowledge. In this presentation I want to present one of the conrnerstones of IYL2015, a partnership between the Galileo Teacher Training Program, Universe Awareness and Globe at Night, the Cosmic Light EDU kit. The aim of this project is to assemble a core set of tools and resources representing our basic knowledge pilars about the Universe and simple means to preserve our night sky.

  19. The Cosmic Origins Spectrograph

    NASA Technical Reports Server (NTRS)

    Green, James C.; Froning, Cynthia S.; Osterman, Steve; Ebbets, Dennis; Heap, Sara H.; Leitherer, Claus; Linsky, Jeffrey L.; Savage, Blair D.; Sembach, Kenneth; Shull, J. Michael; hide

    2010-01-01

    The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in May 2009, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F(sub lambda) approximates 1.0 X 10(exp -14) ergs/s/cm2/Angstrom, COS can achieve comparable signal to noise (when compared to STIS echelle modes) in 1-2% of the observing time. This has led to a significant increase in the total data volume and data quality available to the community. For example, in the first 20 months of science operation (September 2009 - June 2011) the cumulative redshift pathlength of extragalactic sight lines sampled by COS is 9 times that sampled at moderate resolution in 19 previous years of Hubble observations. COS programs have observed 214 distinct lines of sight suitable for study of the intergalactic medium as of June 2011. COS has measured, for the first time with high reliability, broad Lya absorbers and Ne VIII in the intergalactic medium, and observed the HeII reionization epoch along multiple sightlines. COS has detected the first CO emission and absorption in the UV spectra of low-mass circumstellar disks at the epoch of giant planet formation, and detected multiple ionization states of metals in extra-solar planetary atmospheres. In the coming years, COS will continue its census of intergalactic gas, probe galactic and cosmic structure, and explore physics in our solar system and Galaxy.

  20. The Cosmic Origins Spectrograph

    NASA Astrophysics Data System (ADS)

    Green, James C.; Froning, Cynthia S.; Osterman, Steve; Ebbets, Dennis; Heap, Sara H.; Leitherer, Claus; Linsky, Jeffrey L.; Savage, Blair D.; Sembach, Kenneth; Shull, J. Michael; Siegmund, Oswald H. W.; Snow, Theodore P.; Spencer, John; Stern, S. Alan; Stocke, John; Welsh, Barry; Béland, Stéphane; Burgh, Eric B.; Danforth, Charles; France, Kevin; Keeney, Brian; McPhate, Jason; Penton, Steven V.; Andrews, John; Brownsberger, Kenneth; Morse, Jon; Wilkinson, Erik

    2012-01-01

    The Cosmic Origins Spectrograph (COS) is a moderate-resolution spectrograph with unprecedented sensitivity that was installed into the Hubble Space Telescope (HST) in 2009 May, during HST Servicing Mission 4 (STS-125). We present the design philosophy and summarize the key characteristics of the instrument that will be of interest to potential observers. For faint targets, with flux F λ ≈ 1.0 × 10-14 erg cm-2 s-1 Å-1, COS can achieve comparable signal to noise (when compared to Space Telescope Imaging Spectrograph echelle modes) in 1%-2% of the observing time. This has led to a significant increase in the total data volume and data quality available to the community. For example, in the first 20 months of science operation (2009 September-2011 June) the cumulative redshift pathlength of extragalactic sight lines sampled by COS is nine times than sampled at moderate resolution in 19 previous years of Hubble observations. COS programs have observed 214 distinct lines of sight suitable for study of the intergalactic medium as of 2011 June. COS has measured, for the first time with high reliability, broad Lyα absorbers and Ne VIII in the intergalactic medium, and observed the He II reionization epoch along multiple sightlines. COS has detected the first CO emission and absorption in the UV spectra of low-mass circumstellar disks at the epoch of giant planet formation, and detected multiple ionization states of metals in extra-solar planetary atmospheres. In the coming years, COS will continue its census of intergalactic gas, probe galactic and cosmic structure, and explore physics in our solar system and Galaxy.

  1. Cosmic Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Sánchez Almeida, J.; Martínez González, M. J.

    2018-05-01

    Magnetic fields play an important role in many astrophysical processes. They are difficult to detect and characterize since often their properties have to be inferred through interpreting the polarization of the light. Magnetic fields are also challenging to model and understand. Magnetized plasmas behave following highly non-linear differential equations having no general solution, so that every astrophysical problem represents a special case to be studied independently. Hence, magnetic fields are often an inconvenient subject which is overlooked or simply neglected (the elephant in the room, as they are dubbed in poster of the school). Such difficulty burdens the research on magnetic fields, which has evolved to become a very technical subject, with many small disconnected communities studying specific aspects and details. The school tried to amend the situation by providing a unifying view of the subject. The students had a chance to understand the behavior of magnetic fields in all astrophysical contexts, from cosmology to the Sun, and from starbursts to AGNs. The school was planed to present a balanced yet complete review of our knowledge, with excursions into the unknown to point out present and future lines of research. The subject of Cosmic Magnetic Fields was split into seven different topics: cosmic magnetic field essentials, solar magnetic fields, stellar magnetic fields, the role of magnetic fields on AGN feedback, magnetic fields in galaxies, magnetic fields in galaxy clusters and at larger scales, and primordial magnetic fields and magnetic fields in the early Universe. The corresponding lectures were delivered by seven well known and experienced scientists that have played key roles in the major advances of the field during the last years: F. Cattaneo, P. Judge, O. Kochukhov, R. Keppens, R. Beck, K. Dolag, and F. Finelli. Their lectures were recorded and are freely available at the IAC website: http://iactalks.iac.es/talks/serie/19.

  2. A cosmic microwave background feature consistent with a cosmic texture.

    PubMed

    Cruz, M; Turok, N; Vielva, P; Martínez-González, E; Hobson, M

    2007-12-07

    The Cosmic Microwave Background provides our most ancient image of the universe and our best tool for studying its early evolution. Theories of high-energy physics predict the formation of various types of topological defects in the very early universe, including cosmic texture, which would generate hot and cold spots in the Cosmic Microwave Background. We show through a Bayesian statistical analysis that the most prominent 5 degrees -radius cold spot observed in all-sky images, which is otherwise hard to explain, is compatible with having being caused by a texture. From this model, we constrain the fundamental symmetry-breaking energy scale to be (0) approximately 8.7 x 10(15) gigaelectron volts. If confirmed, this detection of a cosmic defect will probe physics at energies exceeding any conceivable terrestrial experiment.

  3. Cosmic rays in the heliosphere

    NASA Technical Reports Server (NTRS)

    Webber, William R.

    1987-01-01

    The different types of cosmic ray particles and their role in the heliosphere are briefly described. The rates of various energetic particles were examined as a function of time and used to derive various differential energy gradients. The Pioneer and Voyager cosmic ray observations throughout the heliosphere are indeed giving a perspective on the three-dimensional character and size of the heliosphere. Most clearly the observations are emphasizing the role that transient variations in the outer heliosphere, and most likely the heliospheric boundary shock, play in the 11 year solar cycle modulation of cosmic rays.

  4. The local time dependence of the anisotropic solar cosmic ray flux.

    PubMed

    Smart, D F; Shea, M A

    2003-01-01

    The distribution of the solar cosmic radiation flux over the earth is not uniform, but the result of complex phenomena involving the interplanetary magnetic field, the geomagnetic field and latitude and longitude of locations on the earth. The latitude effect relates to the geomagnetic shield; the longitude effect relates to local time. For anisotropic solar cosmic ray events the maximum particle flux is always along the interplanetary magnetic field direction, sometimes called the Archimedean spiral path from the sun to the earth. During anisotropic solar cosmic ray event, the locations on the earth viewing "sunward" into the interplanetary magnetic field direction will observe the largest flux (when adjustments are made for the magnetic latitude effect). To relate this phenomena to aircraft routes, for anisotropic solar cosmic ray events that occur during "normal quiescent" conditions, the maximum solar cosmic ray flux (and corresponding solar particle radiation dose) will be observed in the dawn quadrant, ideally at about 06 hours local time. Published by Elsevier Ltd on behalf of COSPAR.

  5. Planetary Habitability over Cosmic-Time Based on Cosmic-Ray Levels

    NASA Astrophysics Data System (ADS)

    Mason, Paul A.; Biermann, Peter L.

    2016-01-01

    Extreme cosmic-ray (CR) fluxes have a negative effect on life when flux densities are high enough to cause excessive biological, especially DNA, damage. The CR history of a planet plays an important role in its potential surface habitation. Both global and local CR conditions determine the ability of life to survive for astrobiologically relevant time periods. We highlight two CR life-limiting factors: 1) General galactic activity, starburst and AGN, was up by about a factor of 30 at redshift 1 - 2, per comoving frame, averaged over all galaxies. And 2) AGN activity is highly intermittent, so extreme brief but powerful bursts (Her A for example) can be detrimental at great distances. This means that during such brief bursts of AGN activity the extragalactic CRs might even overpower the local galactic CRs. But as shown by the starburst galaxy M82, the local CRs in a starburst can also be quite high. Moreover, in our cosmic neighborhood we have several super-massive black holes. These are in M31, M32, M81, NGC5128 (Cen A), and in our own Galaxy, all within about 4 Mpc today. Within about 20 Mpc today there are many more super-massive black holes. Cen A is of course the most famous one now, since it may be a major source of the ultra-high-energy CRs (UHECRs). Folding in what redshift means in terms of cosmic time, this implies that there may have been little chance for life to survive much earlier than Earth's starting epoch. We speculate, on whether the very slow start oflife on Earth is connected to the decay of disturbing CR activity.

  6. Anthropogenic disturbance of element cycles at the Earth's surface.

    PubMed

    Sen, Indra S; Peucker-Ehrenbrink, Bernhard

    2012-08-21

    The extent to which humans are modifying Earth's surface chemistry can be quantified by comparing total anthropogenic element fluxes with their natural counterparts (Klee and Graedel, 2004). We quantify anthropogenic mass transfer of 77 elements from mining, fossil fuel burning, biomass burning, construction activities, and human apportionment of terrestrial net primary productivity, and compare it to natural mass transfer from terrestrial and marine net primary productivity, riverine dissolved and suspended matter fluxes to the ocean, soil erosion, eolian dust, sea-salt spray, cosmic dust, volcanic emissions, and for helium, hydrodynamic escape from the Earth's atmosphere. We introduce an approach to correct for losses during industrial processing of elements belonging to geochemically coherent groups, and explicitly incorporate uncertainties of element mass fluxes through Monte Carlo simulations. We find that at the Earth's surface anthropogenic fluxes of iridium, osmium, helium, gold, ruthenium, antimony, platinum, palladium, rhenium, rhodium and chromium currently exceed natural fluxes. For these elements mining is the major factor of anthropogenic influence, whereas petroleum burning strongly influences the surficial cycle of rhenium. Our assessment indicates that if anthropogenic contributions to soil erosion and eolian dust are considered, anthropogenic fluxes of up to 62 elements surpass their corresponding natural fluxes.

  7. Influence of various amount of diatomaceous earth used as cement substitute on mechanical properties of cement paste

    NASA Astrophysics Data System (ADS)

    Pokorný, Jaroslav; Pavlíková, Milena; Medved, Igor; Pavlík, Zbyšek; Zahálková, Jana; Rovnaníková, Pavla; Černý, Robert

    2016-06-01

    Active silica containing materials in the sub-micrometer size range are commonly used for modification of strength parameters and durability of cement based composites. In addition, these materials also assist to accelerate cement hydration. In this paper, two types of diatomaceous earths are used as partial cement replacement in composition of cement paste mixtures. For raw binders, basic physical and chemical properties are studied. The chemical composition of tested materials is determined using classical chemical analysis combined with XRD method that allowed assessment of SiO2 amorphous phase content. For all tested mixtures, initial and final setting times are measured. Basic physical and mechanical properties are measured on hardened paste samples cured 28 days in water. Here, bulk density, matrix density, total open porosity, compressive and flexural strength, are measured. Relationship between compressive strength and total open porosity is studied using several empirical models. The obtained results give evidence of high pozzolanic activity of tested diatomite earths. Their application leads to the increase of both initial and final setting times, decrease of compressive strength, and increase of flexural strength.

  8. Cosmic ray anisotropies at high energies

    NASA Technical Reports Server (NTRS)

    Martinic, N. J.; Alarcon, A.; Teran, F.

    1986-01-01

    The directional anisotropies of the energetic cosmic ray gas due to the relative motion between the observers frame and the one where the relativistic gas can be assumed isotropic is analyzed. The radiation fluxes formula in the former frame must follow as the Lorentz invariance of dp/E, where p, E are the 4-vector momentum-energy components; dp is the 3-volume element in the momentum space. The anisotropic flux shows in such a case an amplitude, in a rotating earth, smaller than the experimental measurements from say, EAS-arrays for primary particle energies larger than 1.E(14) eV. Further, it is shown that two consecutive Lorentz transformations among three inertial frames exhibit the violation of dp/E invariance between the first and the third systems of reference, due to the Wigner rotation. A discussion of this result in the context of the experimental anisotropic fluxes and its current interpretation is given.

  9. Statistical reconstruction for cosmic ray muon tomography.

    PubMed

    Schultz, Larry J; Blanpied, Gary S; Borozdin, Konstantin N; Fraser, Andrew M; Hengartner, Nicolas W; Klimenko, Alexei V; Morris, Christopher L; Orum, Chris; Sossong, Michael J

    2007-08-01

    Highly penetrating cosmic ray muons constantly shower the earth at a rate of about 1 muon per cm2 per minute. We have developed a technique which exploits the multiple Coulomb scattering of these particles to perform nondestructive inspection without the use of artificial radiation. In prior work [1]-[3], we have described heuristic methods for processing muon data to create reconstructed images. In this paper, we present a maximum likelihood/expectation maximization tomographic reconstruction algorithm designed for the technique. This algorithm borrows much from techniques used in medical imaging, particularly emission tomography, but the statistics of muon scattering dictates differences. We describe the statistical model for multiple scattering, derive the reconstruction algorithm, and present simulated examples. We also propose methods to improve the robustness of the algorithm to experimental errors and events departing from the statistical model.

  10. Mapping of cosmic radiation dose in Croatia.

    PubMed

    Poje, M; Vuković, B; Radolić, V; Miklavčić, I; Faj, D; Varga Pajtler, M; Planinić, J

    2012-01-01

    The Earth is continually bombarded by high-energy particles coming from the outer space and the sun. These particles, termed cosmic radiation, interact with nuclei of atmospheric constituents and decrease in intensity with depth in the atmosphere. Measurements of photon and gamma radiation, performed with a Radiameter at 1 m above the ground, indicated dose rates of 50-100 nSv/h. The neutron dose rate was measured with the CR-39 track etch detector calibrated by the CERN-EU high-energy Reference Field (CERF) facility. Correlation between neutron dose rates and altitudes at 36 sites was examined in order to obtain a significant positive correlation coefficient; the resulting linear regression enabled estimation of a neutron dose at particular altitude. The measured neutron dose rate in Osijek (altitude of 89 m, latitude of 45.31° N) was 110 nSv/h. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Part II: Cosmic Winter.

    ERIC Educational Resources Information Center

    Overbye, Dennis

    1984-01-01

    Discusses conflicting theories that explain how and why bombardment by comets spells periodic disaster for life on earth. Dislodgment of comets occurs from a vast cloud that envelops the solar system by gravitational forces of either a companion star of the sun or a dust cloud. (BC)

  12. Cosmic Ray-Air Shower Measurement from Space

    NASA Technical Reports Server (NTRS)

    Takahashi, Yoshiyuki

    1997-01-01

    A feasibility study has been initiated to observe from space the highest energy cosmic rays above 1021 eV. A satellite observatory concept, the Maximum-energy Auger (Air)-Shower Satellite (MASS), is recently renamed as the Orbital Wide-angle Collector (OWL) by taking its unique feature of using a very wide field-of-view (FOV) optics. A huge array of imaging devices (about 10(exp 6) pixels) is required to detect and record fluorescent light profiles of cosmic ray cascades in the atmosphere. The FOV of MASS could extend to as large as about 60 in. diameter, which views (500 - 1000 km) of earth's surface and more than 300 - 1000 cosmic ray events per year could be observed above 1020 eV. From far above the atmosphere, the MASS/OWL satellite should be capable of observing events at all angles including near horizontal tracks, and would have considerable aperture for high energy photon and neutrino observation. With a large aperture and the spatial and temporal resolution, MASS could determine the energy spectrum, the mass composition, and arrival anisotropy of cosmic rays from 1020 eV to 1022 eV; a region hitherto not explored by ground-based detectors such as the Fly's Eye and air-shower arrays. MASS/OWL's ability to identify cosmic neutrinos and gamma rays may help providing evidence for the theory which attributes the above cut-off cosmic ray flux to the decay of topological defects. Very wide FOV optics system of MASS/OWL with a large array of imaging devices is applicable to observe other atmospheric phenomena including upper atmospheric lightning. The wide FOV MASS optics being developed can also improve ground-based gamma-ray observatories by allowing simultaneous observation of many gamma ray sources located at different constellations.

  13. Terrestrial Effects of High Energy Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Atri, Dimitra

    2011-01-01

    On geological timescales, the Earth is likely to be exposed to an increased flux of high energy cosmic rays (HECRs) from astrophysical sources such as nearby supernovae, gamma ray bursts or by galactic shocks. These high-energy particles strike the Earth's atmosphere initiating an extensive air shower. As the air shower propagates deeper, it ionizes the atmosphere by producing charged secondary particles. Increased ionization could lead to changes in atmospheric chemistry, resulting in ozone depletion. This could increase the flux of solar UVB radiation at the surface, which is potentially harmful to living organisms. Increased ionization affects the global electrical circuit can could possibly enhance the low-altitude cloud formation rate. Secondary particles such as muons and thermal neutrons produced as a result of nuclear interactions are able to reach the ground, enhancing the biological radiation dose. The muon flux dominates radiation dose from cosmic rays causing DNA damage and increase in the mutation rates, which can have serious biological implications for terrestrial and sub-terrestrial life. This radiation dose is an important constraint on the habitability of a planet. Using CORSIKA, we perform massive computer simulations and construct lookup tables from 10 GeV - 1 PeV primaries (1 PeV - 0.1 ZeV in progress), which can be used to quantify these effects. These tables are freely available to the community and can be used for other studies, not necessarily relevant to Astrobiology. We use these tables to study the terrestrial implications of galactic shock generated by the infall of our galaxy toward the Virgo cluster. This could be a possible mechanism explaining the observed periodicity in biodiversity in paleobiology databases.

  14. The dawn of the particle astronomy era in ultra-high-energy cosmic rays.

    PubMed

    Bauleo, Pablo M; Martino, Julio Rodríguez

    2009-04-16

    Cosmic rays are charged particles arriving at the Earth from space. Those at the highest energies are particularly interesting because the physical processes that could create or accelerate them are at the limit of our present knowledge. They also open the window to particle astronomy, as the magnetic fields along their paths are not strong enough to deflect their trajectories much from a straight line. The Pierre Auger Observatory is the largest cosmic-ray detector on Earth, and as such is beginning to resolve past observational disagreements regarding the origin and propagation of these particles.

  15. Calculation of cosmic ray induced single event upsets: Program CRUP (Cosmic Ray Upset Program)

    NASA Astrophysics Data System (ADS)

    Shapiro, P.

    1983-09-01

    This report documents PROGRAM CRUP, COSMIC RAY UPSET PROGRAM. The computer program calculates cosmic ray induced single-event error rates in microelectronic circuits exposed to several representative cosmic-ray environments.

  16. Rare earth elements in intertidal sediments of Bohai Bay, China: concentration, fractionation and the influence of sediment texture.

    PubMed

    Zhang, Yong; Gao, Xuelu; Arthur Chen, Chen-Tung

    2014-07-01

    Surface sediments from intertidal Bohai Bay were assessed using a four-step sequential extraction procedure to determine their concentrations of rare earth elements (REEs) and the chemical forms in which those elements were present. The normalized ratios La/Gd and La/Yb showed that LREE contents were not significantly higher than the middle REEs or HREE contents. A negative Ce anomaly and positive Eu were observed in sand and silty sand sediments, whereas no significant Ce or Eu anomaly was found in clayey silt sediments. Residual fraction of REEs accounted for the majority of their total concentrations. Middle REEs were more easily leached than other REEs, especially in clayey silt sediment. REEs contents in the surface sediment from the intertidal Bohai Sea were consistent with data from the upper continental crust and China shallow sea sediments, indicating that they were generally unaffected by heavily anthropogenic effects from adjacent areas. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Estimates of radiation exposure from solar cosmic rays in SST altitudes

    NASA Technical Reports Server (NTRS)

    Foelsche, T.

    1974-01-01

    Factors influencing crew and passenger exposure to solar and galactic cosmic rays that is expected to occur during flights of supersonic transport aircraft are discussed, and some possibilities are considered for decreasing such exposure.

  18. Cosmic string wakes

    NASA Technical Reports Server (NTRS)

    Stebbins, Albert; Veeraraghavan, Shoba; Silk, Joseph; Brandenberger, Robert; Turok, Neil

    1987-01-01

    Accretion of matter onto wakes left behind by horizon-sized pieces of cosmic string is investigated, and the effects of wakes on the large-scale structure of the universe are determined. Accretion of cold matter onto wakes, the effects of a long string on fluids with finite velocity dispersion or sound speeds, the interactions between loops and wakes, and the conditions for wakes to survive disruption by loops are discussed. It is concluded that the most important wakes are those which were formed at the time of equal matter and radiation density. This leads to sheetlike overdense regions of galaxies with a mean separation in agreement with the scale of the bubbles of de Lapparent, Geller, and Huchra (1986). However, for the value of G(mu) favored from galaxy formation considerations in a universe with cold dark matter, a wake accretes matter from a distance of only about 1.5 Mpc, which is much less than the distance between the wakes.

  19. The Cosmic Century

    NASA Astrophysics Data System (ADS)

    Longair, Malcolm S.

    2013-04-01

    Part I. Stars and Stellar Evolution up to the Second World War: 1. The legacy of the nineteenth century; 2. The classification of stellar spectra; 3. Stellar structure and evolution; 4. The end points of stellar evolution; Part II. The Large-Scale Structure of the Universe, 1900-1939: 5. The Galaxy and the nature of spiral nebulae; 6. The origins of astrophysical cosmology; Part III. The Opening up of the Electromagnetic Spectrum: 7. The opening up of the electromagnetic spectrum and the new astronomies; Part IV. The Astrophysics of Stars and Galaxies since 1945: 8. Stars and stellar evolution; 9. The physics of the interstellar medium; 10. The physics of galaxies and clusters of galaxies; 11. High-energy astrophysics; Part V. Astrophysical Cosmology since 1945: 12. Astrophysical cosmology; 13. The determination of cosmological parameters; 14. The evolution of galaxies and active galaxies with cosmic epoch; 15. The origin of galaxies and the large-scale structure of the Universe; 16. The very early Universe; References; Name index; Object index; Subject index.

  20. A cosmic couple

    NASA Image and Video Library

    2015-08-17

    Here we see the spectacular cosmic pairing of the star Hen 2-427 — more commonly known as WR 124 — and the nebula M1-67 which surrounds it. Both objects, captured here by the NASA/ESA Hubble Space Telescope are found in the constellation of Sagittarius and lie 15 000 light-years away. The star Hen 2-427 shines brightly at the very centre of this explosive image and around the hot clumps of gas are ejected into space at over 150 000 kilometres per hour. Hen 2-427 is a Wolf–Rayet star, named after the astronomers Charles Wolf and Georges Rayet. Wolf–Rayet are super-hot stars characterised by a fierce ejection of mass. The nebula M1-67 is estimated to be no more than 10 000 years old — just a baby in astronomical terms — but what a beautiful and magnificent sight it makes. A version of this image was released in 1998, but has now been re-reduced with the latest software.

  1. Boson peak of alkali and alkaline earth silicate glasses: influence of the nature and size of the network-modifying cation.

    PubMed

    Richet, Nicolas F

    2012-01-21

    The influence of the size of the alkaline earth cation on the boson peak of binary metasilicate glasses, MSiO(3) (M = Mg, Ca, Sr, Ba), has been investigated from vibrational densities of states determined by inversion of low-temperature heat capacities. As given both by C(p)/T(3) and g(ω)/ω(2), the intensity of the boson peak undergoes a 7-fold increase from Mg to Ba, whereas its temperature and frequency correlatively decrease from 18 to 10 K and from 100 to 20 cm(-1), respectively. The boson peak results from a combination of librations of SiO(4) tetrahedra and localized vibrations of network-modifying cations with non-bridging oxygens whose contribution increases markedly with the ionic radius of the alkaline earth. As a function of ionic radii, the intensity for Sr and Ba varies in the same way as previously found for alkali metasilicate glasses. The localized vibrations involving alkali and heavy alkaline earth cations appear to be insensitive to the overall glass structure. Although the new data are coherent with an almost linear relationship between the temperature of the boson peak and transverse sound velocity, pure SiO(2) and SiO(2)-rich glasses make marked exceptions to this trend because of the weak transverse character of SiO(4) librations. Finally, the universality of the calorimetric boson peak is again borne out because all data for silicate glasses collapse on the same master curve when plotted in a reduced form (C(P)∕/T(3))/(C(P)/T(3))(b) vs. T/T(b). © 2012 American Institute of Physics

  2. The Fastest Humans on Earth: Environmental Surroundings and Family Influences That Spark Talent Development in Olympic Speed Skaters

    ERIC Educational Resources Information Center

    Ott Schacht, Carol L.; Kiewra, Kenneth A.

    2018-01-01

    This qualitative research study addressed this question: What influence did early environmental surroundings and family have on the talent development of a cohort of American speed skaters who each competed in four Olympic Games during the 1980s and 1990s? The skaters were Bonnie Blair, Dave Cruikshank, and Dan Jansen. Independent interviews with…

  3. PREFACE: 23rd European Cosmic Ray Symposium (and 32nd Russian Cosmic Ray Conference)

    NASA Astrophysics Data System (ADS)

    Erlykin, A. D.; Kokoulin, R. P.; Lidvansky, A. S.; Meroshnichenko, L. I.; Panasyuk, M. I.; Panov, A. D.; Wolfendale, A. W.

    2013-02-01

    The 23rd European Cosmic Ray Symposium (ECRS) took place in Moscow at the Lomonosov Moscow State University (3-7 July 2012), and was excellently organized by the Skobeltsyn Institute of Nuclear Physics of the Lomonosov Moscow State University, with the help of the Russian Academy of Sciences and the Council on the Complex Problem of Cosmic Rays of the Russian Academy of Sciences. The first symposia were held in 1968 in Lodz, Poland (high energy, extensive air showers and astrophysical aspects) and in Bern (solar and heliospheric phenomena) and the two 'strands' joined together in 1976 with the meeting in Leeds. Since then the symposia, which have been very successful, have covered all the major topics with some emphasis on European collaborations and on meeting the demands of young scientists. Initially, a driving force was the need to overcome the divisions caused by the 'Cold War' but the symposia continued even when that threat ceased and they have shown no sign of having outlived their usefulness. 2012 has been an important year in the history of cosmic ray studies, in that it marked the centenary of the discovery of enigmatic particles in the perilous balloon ascents of Victor Hess. A number of conferences have taken place in Western Europe during the year, but this one took place in Moscow as a tribute to the successful efforts of many former USSR and other Eastern European scientists in discovering the secrets of the subject, often under very difficult conditions. The symposium covers a wide range of scientific issues divided into the following topics: PCR-IPrimary cosmic rays I (E < 1015 eV) PCR-IIPrimary cosmic rays II (E > 1015 eV) MNCosmic ray muons and neutrinos GAGeV and TeV gamma astronomy SHEnergetic particles in the heliosphere (solar and anomalous CRs and GCR modulation) GEOCosmic rays and geophysics (energetic particles in the atmosphere and magnetosphere of the Earth) On a personal note, as I step down as co-founder and chairman of the

  4. Cosmic archaeology with gravitational waves from cosmic strings

    NASA Astrophysics Data System (ADS)

    Cui, Yanou; Lewicki, Marek; Morrissey, David E.; Wells, James D.

    2018-06-01

    Cosmic strings are generic cosmological predictions of many extensions of the standard model of particle physics, such as a U (1 )' symmetry-breaking phase transition in the early Universe or remnants of superstring theory. Unlike other topological defects, cosmic strings can reach a scaling regime that maintains a small fixed fraction of the total energy density of the Universe from a very early epoch until today. If present, they will oscillate and generate gravitational waves with a frequency spectrum that imprints the dominant sources of total cosmic energy density throughout the history of the Universe. We demonstrate that current and future gravitational wave detectors, such as LIGO and LISA, could be capable of measuring the frequency spectrum of gravitational waves from cosmic strings and discerning the energy composition of the Universe at times well before primordial nucleosynthesis and the cosmic microwave background where standard cosmology has yet to be tested. This work establishes a benchmark case that gravitational waves may provide an unprecedented, powerful tool for probing the evolutionary history of the very early Universe.

  5. Heliospheric Modulation of Galactic Cosmic Rays; Diurnal Variability Abstract Details

    NASA Astrophysics Data System (ADS)

    Kalu, D. F.; Okpala, K. C.

    2017-12-01

    We have studied the variability of Cosmic rays flux during solar quiet days at mid and high latitudes in the Northern Hemisphere. By using the five (5) quietest days for each month and the five disturbed days for each month, the monthly mean diurnal variation of cosmic ray anisotropy have been derived for the period 1999-2015, which covers part of cycles 23, and cycle 24. This study seeks to understand the heliospheric contribution to the variation of these Cosmic rays on quietest days, three stations (Inuvik, Moscow, Rome) Neutron Monitors were employed. This study seeks to understand the important features of the high latitude and mid latitude diurnal wave, and how solar and geomagnetic activity may be influencing the wave characteristics. Cosmic ray wave characteristics were obtained by discrete Fourier transform (DFT). The mean, diurnal amplitude, phase and dispersion for each month's diurnal wave were calculated and profiled. There was clear indication that the terrestrial effect on the variability of the monthly mean was more associated with geomagnetic activity rather than rigidity of the cosmic rays. Correlation of the time series of these wave characteristic with solar and geomagnetic activity index showed better association with solar activity.

  6. Use of geochemical signatures, including rare earth elements, in mosses and lichens to assess spatial integration and the influence of forest environment

    NASA Astrophysics Data System (ADS)

    Gandois, L.; Agnan, Y.; Leblond, S.; Séjalon-Delmas, N.; Le Roux, G.; Probst, A.

    2014-10-01

    In order to assess the influence of local environment and spatial integration of Trace Metals (TM) by biomonitors, Al, As, Cd, Cr, Cs, Cu, Fe, Mn, Ni, Pb, Sb, Sn, V and Zn and some rare earth element (REE) concentrations have been measured in lichens and mosses collected in three French forest sites located in three distinct mountainous areas, as well as in the local soil and bedrock, and in both bulk deposition (BD) and throughfall (TF). Similar enrichment factors (EF) were calculated using lichens and mosses and local bedrock for most elements, except for Cs, Mn, Ni, Pb, and Cu which were significantly (KW, p < 0.05) more enriched in mosses. Similar REE ratios were measured in soils, bedrock, lichens and mosses at each study sites, indicating a regional integration of atmospheric deposition by both biomonitors. Both TM signature and REE composition of mosses revealed that this biomonitor is highly influenced by throughfall composition, and reflect atmospheric deposition interaction with the forest canopy. This explained the higher enrichment measured in mosses for elements which concentration in deposition were influenced by the canopy, either due to leaching (Mn), direct uptake (Ni), or dry deposition dissolution (Pb, Cu, Cs).

  7. The variations of oxygen emissions in corresponding to Earth's aurora in low latitude region under influence of solar wind dynamics

    NASA Astrophysics Data System (ADS)

    Jamlongkul, P.; Wannawichian, S.

    2017-12-01

    Earth's aurora in low latitude region was studied via time variations of oxygen emission spectra, simultaneously with solar wind data. The behavior of spectrum intensity, in corresponding with solar wind condition, could be a trace of aurora in low latitude region including some effects of high energetic auroral particles. Oxygen emission spectral lines were observed by Medium Resolution Echelle Spectrograph (MRES) at 2.4-m diameter telescope at Thai National Observatory, Inthanon Mountain, Chiang Mai, Thailand, during 1-5 LT on 5 and 6 February 2017. The observed spectral lines were calibrated via Dech95 - 2D image processing program and Dech-Fits spectra processing program for spectrum image processing and spectrum wavelength calibration, respectively. The variations of observed intensities each day were compared with solar wind parameters, which are magnitude of IMF (|BIMF|) including IMF in RTN coordinate (BR, BT, BN), ion density (ρ), plasma flow pressure (P), and speed (v). The correlation coefficients between oxygen spectral emissions and different solar wind parameters were found to vary in both positive and negative behaviors.

  8. The analysis of influence of field of co-rotation on motion of submicronic particles in the Earth's plasmasphere

    NASA Astrophysics Data System (ADS)

    Yakovlev, A. B.

    2018-05-01

    The analysis of the motion of micro-particles with radii of several dozens of nanometers in the Earth's plasmasphere has confirmed that the earlier proved statement about conservation of the form for an orbit of a particle with constant electric charge which moves in superposition of the central gravitational field and the field of a magnetic dipole is true also for the case of a quasi-equilibrium electric charge. For a wide range of altitudes and the sizes of micro-particles other forces that act on the charged grain make considerably smaller impact on its motion. On the basis of numerical simulation it has been shown that for motion in an equatorial plane the field of co-rotation leads to very small monotonous growth of the semimajor axis and an orbit eccentricity, and for not-equatorial orbits there are fluctuations of the semimajor axis, an eccentricity and an inclination of an orbit with the period that considerably exceeds the period of orbital motion. In this paper, on the basis of the analysis of the canonical equations of the motion of a micro-particle in superposition of the central gravitational field and the field of co-rotation the explanation of the time dependences obtained numerically for the basic characteristics of an orbit of a micro-particle is proposed.

  9. Nanomagnetic behavior of fullerene thin films in Earth magnetic field in dark and under polarization light influences.

    PubMed

    Koruga, Djuro; Nikolić, Aleksandra; Mihajlović, Spomenko; Matija, Lidija

    2005-10-01

    In this paper magnetic fields intensity of C60 thin films of 60 nm and 100 nm thickness under the influence of polarization lights are presented. Two proton magnetometers were used for measurements. Significant change of magnetic field intensity in range from 2.5 nT to 12.3 nT is identified as a difference of dark and polarization lights of 60 nm and 100 nm thin films thickness, respectively. Specific power density of polarization light was 40 mW/cm2. Based on 200 measurement data average value of difference between magnetic intensity of C60 thin films, with 60 nm and 100 nm thickness, after influence of polarization light, were 3.9 nT and 9.9 nT respectively.

  10. Earth Observation

    NASA Image and Video Library

    2014-06-01

    ISS040-E-006327 (1 June 2014) --- A portion of International Space Station solar array panels and Earth?s horizon are featured in this image photographed by an Expedition 40 crew member on the space station.

  11. The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations.

    PubMed

    Neyrinck, Mark C; Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

    2018-04-01

    For over 20 years, the term 'cosmic web' has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile 'spiderwebs' is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos.

  12. The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations

    NASA Astrophysics Data System (ADS)

    Neyrinck, Mark C.; Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

    2018-04-01

    For over 20 years, the term `cosmic web' has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile `spiderwebs' is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos.

  13. Robust constraint on cosmic textures from the cosmic microwave background.

    PubMed

    Feeney, Stephen M; Johnson, Matthew C; Mortlock, Daniel J; Peiris, Hiranya V

    2012-06-15

    Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic textures. Textures are a type of topological defect that can be produced during a cosmological phase transition in the early Universe, and which leave characteristic hot and cold spots in the CMB. We apply bayesian methods to carry out a rigorous test of the texture hypothesis, using full-sky data from the Wilkinson Microwave Anisotropy Probe. We conclude that current data do not warrant augmenting the standard cosmological model with textures. We rule out at 95% confidence models that predict more than 6 detectable cosmic textures on the full sky.

  14. Fitting cosmic microwave background data with cosmic strings and inflation.

    PubMed

    Bevis, Neil; Hindmarsh, Mark; Kunz, Martin; Urrestilla, Jon

    2008-01-18

    We perform a multiparameter likelihood analysis to compare measurements of the cosmic microwave background (CMB) power spectra with predictions from models involving cosmic strings. Adding strings to the standard case of a primordial spectrum with power-law tilt ns, we find a 2sigma detection of strings: f10=0.11+/-0.05, where f10 is the fractional contribution made by strings in the temperature power spectrum (at l=10). CMB data give moderate preference to the model ns=1 with cosmic strings over the standard zero-strings model with variable tilt. When additional non-CMB data are incorporated, the two models become on a par. With variable ns and these extra data, we find that f10<0.11, which corresponds to Gmicro<0.7x10(-6) (where micro is the string tension and G is the gravitational constant).

  15. Cosmic Dawn Intensity Mapper

    NASA Astrophysics Data System (ADS)

    Cooray, Asantha

    2018-01-01

    Cosmic Dawn Intensity Mapper (CDIM) is a 1.0m-class infrared telescope capable of three-dimensional spectro-imaging observations over the wavelength range of 0.75 to 7.5 microns, at a spectral resolving power at or better than 300. This will be achieved with linear variablefilters (LVFs) and a large field-of-view (FoV). The survey strategy using spacecraft operations following a shift and stare mode will result in more than 1300 independent narrow-band spectral images of the sky at a given location. Currently prioritized science programs, taking over three-years of a five-year mission, will be accomplished with a two-tiered wedding-cake survey with the shallowest spanning close to 300 sq. degrees and the deepest tier of about 25 sq. degrees.The remaining two-years could be used for additional survey programs (the wide tier can be expanded to 1000 sq. degrees) or for use by the astronomical community through a General Observing (GO) campaign. CDIM survey data will allow us to (i) establish the initial mass function of stars in galaxies present during reionization, (ii) definitively address AGN/quasar contribution to the reionization photon budget; (iii) establish the environmental dependence of star-formation during reionization through clustering and other environmental measurements; (iv) establish the metal abundance of first-light galaxies during reionization over two decades of stellar mass; (v) measure 3D intensity fluctuations during reionization in both Ly-alpha and H-alpha; and (vi) combine intensity fluctuations with 21-cm data to establish the topology of reionization bubbles.

  16. Measuring the Cosmic Particle Radiation from electrons to actinides - HNX/TIGERISS

    NASA Astrophysics Data System (ADS)

    Mitchell, John

    2017-01-01

    The Heavy Nuclei eXplorer (HNX) mission will measure the abundances of nuclei from Carbon (Z =6) to Curium (Z =96) in the cosmic radiation with the resolution to identify the atomic number of each detected nucleus. HNX will measure a significant number of actinides. HNX utilizes two high-precision instruments, the Extremely-heavy Cosmic-ray Composition Observer (ECCO) and the Cosmic-Ray Trans-Iron Galactic Element Recorder (CosmicTIGER), located in a SpaceX DragonLab capsule orbiting the Earth. This talk will discuss the motivating science, the HNX mission, the design and performance of the HNX instruments, and another new instrument, TIGERISS (Trans-Iron Galactic Element Recorder on the ISS), that will be proposed as an intermediate between SuperTIGER and HNX.

  17. The shape of the extragalactic cosmic ray spectrum from galaxy clusters

    SciTech Connect

    Harari, Diego; Mollerach, Silvia; Roulet, Esteban, E-mail: harari@cab.cnea.gov.ar, E-mail: mollerach@cab.cnea.gov.ar, E-mail: roulet@cab.cnea.gov.ar

    2016-08-01

    We study the diffusive escape of cosmic rays from a central source inside a galaxy cluster to obtain the suppression in the outgoing flux appearing when the confinement times get comparable or larger than the age of the sources. We also discuss the attenuation of the flux due to the interactions of the cosmic rays with the cluster medium, which can be sizeable for heavy nuclei. The overall suppression in the total cosmic ray flux expected on Earth is important to understand the shape of the extragalactic contribution to the cosmic ray spectrum for E / Z < 1 EeVmore » . This suppression can also be relevant to interpret the results of fits to composition-sensitive observables measured at ultra-high energies.« less

  18. Paradoxes of Cosmic Flights

    DTIC Science & Technology

    1977-04-26

    less energy than in tha case of a takeoff from the surface of the Sarth. during such a takeoff from the earth the rocket motor ought to accomplish a...the energy point of view to set the roc- ket in motion* at the point closest to the *arth, the perigee, or at the most distant from it,—the apogee...than 1/33 parts of tbat energy that is necjfjessary during initial braking at the nearest-to-the»eaa?tfl ’:■’■- :,’-::::-:’.. :’.-:--:’.--£. ■■K

  19. Cosmic logic: a computational model

    NASA Astrophysics Data System (ADS)

    Vanchurin, Vitaly

    2016-02-01

    We initiate a formal study of logical inferences in context of the measure problem in cosmology or what we call cosmic logic. We describe a simple computational model of cosmic logic suitable for analysis of, for example, discretized cosmological systems. The construction is based on a particular model of computation, developed by Alan Turing, with cosmic observers (CO), cosmic measures (CM) and cosmic symmetries (CS) described by Turing machines. CO machines always start with a blank tape and CM machines take CO's Turing number (also known as description number or Gödel number) as input and output the corresponding probability. Similarly, CS machines take CO's Turing number as input, but output either one if the CO machines are in the same equivalence class or zero otherwise. We argue that CS machines are more fundamental than CM machines and, thus, should be used as building blocks in constructing CM machines. We prove the non-computability of a CS machine which discriminates between two classes of CO machines: mortal that halts in finite time and immortal that runs forever. In context of eternal inflation this result implies that it is impossible to construct CM machines to compute probabilities on the set of all CO machines using cut-off prescriptions. The cut-off measures can still be used if the set is reduced to include only machines which halt after a finite and predetermined number of steps.

  20. Rare Isotopes in Cosmic Explosions and Accelerators on Earth

    ScienceCinema

    Schatz, Hendrick

    2017-12-28

    Rare isotopes are nature’s stepping stones to produce the heavy elements, and they are produced in large quantities in stellar explosions. Despite their fleeting existence, they shape the composition of the universe and the observable features of stellar explosions. The challenge for nuclear science is to produce and study the very same rare isotopes so as to understand the origin of the elements and a range of astronomical observations. I will review the progress that has been made to date in astronomy and nuclear physics, and the prospects of finally addressing many of the outstanding issues with the future Facility for Rare Isotope Beams (FRIB), which DOE will build at Michigan State University.

  1. Cosmic impact: What are the odds?

    NASA Astrophysics Data System (ADS)

    Harris, A. W.

    2009-12-01

    Firestone et al. (PNAS 104, 16016-16021, 2007) propose that the impact of a ~4 km diameter comet (or multiple bodies making up a similar mass) led to the Younger Dryas cooling and extinction of megafauna in North America, 12,900 years ago. Even more provocatively, Firestone et al. (Cycle of Cosmic Catastrophes, Bear & Co. Books, 2006, 392pp), suggest that a nearby supernova may have produced a comet shower leading to the impact event, either by disturbing the Oort Cloud or by direct injection of 4-km comet-like bodies to the solar neighborhood. Here we show: (a) A supernova shockwave or mass ejection is not capable of triggering a shower of comets from the Oort Cloud. (b) An Oort Cloud shower from whatever cause would take 100,000 years or more for the perturbed comets to arrive in the inner solar system, and the peak flux would persist for some hundreds of thousands more years. (c) Even if all 20 solar masses or so of ejected matter from a SN were in the form of 4-km diameter balls, the probability of even one such ball hitting the Earth from an event 100 light years away would be about 3e-5. (d) A 4-km diameter ball traveling fast enough to get here from 100 LY away in some tens of thousands of years would deliver the energy of a 50 km diameter impactor traveling at typical Earth-impact velocity (~20 km/sec). We review the current impact flux on the Earth from asteroids and comets, and show that the probability of an impact of a 4-km diameter asteroid in an interval of 13,000 years is about one in a thousand, and the probability of a comet impact of that size is a few in a million. An "impact shower" caused by the injection or breakup of comets or asteroids in the inner solar system by whatever means would take tens to hundreds of thousands of years to clear out, thus the population of NEOs we see now with our telescopic surveys is what we’ve had for the last few tens of thousands of years, at least. Faced with such low odds, the evidence that such a large

  2. Detection prospects for the Cosmic Neutrino Background using laser interferometers

    SciTech Connect

    Domcke, Valerie; Spinrath, Martin, E-mail: valerie.domcke@apc.univ-paris7.fr, E-mail: martin.spinrath@cts.nthu.edu.tw

    The cosmic neutrino background is a key prediction of Big Bang cosmology which has not been observed yet. The movement of the earth through this neutrino bath creates a force on a pendulum, as if it were exposed to a cosmic wind. We revise here estimates for the resulting pendulum acceleration and compare it to the theoretical sensitivity of an experimental setup where the pendulum position is measured using current laser interferometer technology as employed in gravitational wave detectors. We discuss how a significant improvement of this setup can be envisaged in a micro gravity environment. The proposed setup couldmore » also function as a dark matter detector in the sub-MeV range, which currently eludes direct detection constraints.« less

  3. Inverse Flux versus Pressure of Muons from Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Buitrago, D.; Armendariz, R.

    2017-12-01

    When an incoming cosmic ray proton or atom collides with particles in earth's atmosphere a shower of secondary muons is created. Cosmic ray muon flux was measured at the Queensborough Community College using a QuarkNet detector consisting of three stacked scintillator muon counters and a three-fold coincidence trigger. Data was recorded during a three-day period during a severe weather storm that occurred from March 13-17, 2017. A computer program was created in Python to read the muon flux rate and atmospheric pressure sensor readings from the detector's data acquisition board. The program converts the data from hexadecimal to decimal, re-bins the data in a more suitable format, creates and overlays plots of muon flux with atmospheric pressure. Results thus far show a strong correlation between muon flux and atmospheric pressure. More data analysis will be done to verify the above conclusion.

  4. Measurement of Cosmic-Ray TeV Electrons

    NASA Astrophysics Data System (ADS)

    Schubnell, Michael; Anderson, T.; Bower, C.; Coutu, S.; Gennaro, J.; Geske, M.; Mueller, D.; Musser, J.; Nutter, S.; Park, N.; Tarle, G.; Wakely, S.

    2011-09-01

    The Cosmic Ray Electron Synchrotron Telescope (CREST) high-altitude balloon experiment is a pathfinding effort to detect for the first time multi-TeV cosmic-ray electrons. At these energies distant sources will not contribute to the local electron spectrum due to the strong energy losses of the electrons and thus TeV observations will reflect the distribution and abundance of nearby acceleration sites. CREST will detect electrons indirectly by measuring the characteristic synchrotron photons generated in the Earth's magnetic field. The instrument consist of an array of 1024 BaF2 crystals viewed by photomultiplier tubes surrounded by a hermetic scintillator shield. Since the primary electron itself need not traverse the payload, an effective detection area is achieved that is several times the nominal 6.4 m2 instrument. CREST is scheduled to fly in a long duration circumpolar orbit over Antarctica during the 2011-12 season.

  5. DNA sequencing and predictions of the cosmic theory of life

    NASA Astrophysics Data System (ADS)

    Wickramasinghe, N. Chandra

    2013-01-01

    The theory of cometary panspermia, developed by the late Sir Fred Hoyle and the present author argues that life originated cosmically as a unique event in one of a great multitude of comets or planetary bodies in the Universe. Life on Earth did not originate here but was introduced by impacting comets, and its further evolution was driven by the subsequent acquisition of cosmically derived genes. Explicit predictions of this theory published in 1979-1981, stating how the acquisition of new genes drives evolution, are compared with recent developments in relation to horizontal gene transfer, and the role of retroviruses in evolution. Precisely-stated predictions of the theory of cometary panspermia are shown to have been verified.

  6. DNA Sequencing and Predictions of the Cosmic Theory of Life

    NASA Astrophysics Data System (ADS)

    Wickramasinghe, N. Chandra

    The theory of cometary panspermia, developed by the late Sir Fred Hoyle and the present author argues that life originated cosmically as a unique event in one of a great multitude of comets or planetary bodies in the Universe. Life on Earth did not originate here but was introduced by impacting comets, and its further evolution was driven by the subsequent acquisition of cosmically derived genes. Explicit predictions of this theory published in 1979-1981, stating how the acquisition of new genes drives evolution, are compared with recent developments in relation to horizontal gene transfer, and the role of retroviruses in evolution. Precisely-stated predictions of the theory of cometary panspermia are shown to have been verified.

  7. Detection prospects for the Cosmic Neutrino Background using laser interferometers

    NASA Astrophysics Data System (ADS)

    Domcke, Valerie; Spinrath, Martin

    2017-06-01

    The cosmic neutrino background is a key prediction of Big Bang cosmology which has not been observed yet. The movement of the earth through this neutrino bath creates a force on a pendulum, as if it were exposed to a cosmic wind. We revise here estimates for the resulting pendulum acceleration and compare it to the theoretical sensitivity of an experimental setup where the pendulum position is measured using current laser interferometer technology as employed in gravitational wave detectors. We discuss how a significant improvement of this setup can be envisaged in a micro gravity environment. The proposed setup could also function as a dark matter detector in the sub-MeV range, which currently eludes direct detection constraints.

  8. Spallation processes and nuclear interaction products of cosmic rays.

    PubMed

    Silberberg, R; Tsao, C H

    1990-08-01

    Most cosmic-ray nuclei heavier than helium have suffered nuclear collisions in the interstellar gas, with transformation of nuclear composition. The isotopic and elemental composition at the sources has to be inferred from the observed composition near the Earth. The source composition permits tests of current ideas on sites of origin, nucleosynthesis in stars, evolution of stars, the mixing and composition of the interstellar medium and injection processes prior to acceleration. The effects of nuclear spallation, production of radioactive nuclides and the time dependence of their decay provide valuable information on the acceleration and propagation of cosmic rays, their nuclear transformations, and their confinement time in the Galaxy. The formation of spallation products that only decay by electron capture and are relatively long-lived permits an investigation of the nature and density fluctuations (like clouds) of the interstellar medium. Since nuclear collisions yield positrons, antiprotons, gamma rays and neutrinos, we shall discuss these topics briefly.

  9. Key scientific problems from Cosmic Ray History

    NASA Astrophysics Data System (ADS)

    Lev, Dorman

    2016-07-01

    Recently was published the monograph "Cosmic Ray History" by Lev Dorman and Irina Dorman (Nova Publishers, New York). What learn us and what key scientific problems formulated the Cosmic Ray History? 1. As many great discoveries, the phenomenon of cosmic rays was discovered accidentally, during investigations that sought to answer another question: what are sources of air ionization? This problem became interesting for science about 230 years ago in the end of the 18th century, when physics met with a problem of leakage of electrical charge from very good isolated bodies. 2. At the beginning of the 20th century, in connection with the discovery of natural radioactivity, it became apparent that this problem is mainly solved: it was widely accepted that the main source of the air ionization were α, b, and γ - radiations from radioactive substances in the ground (γ-radiation was considered as the most important cause because α- and b-radiations are rapidly absorbed in the air). 3. The general accepted wrong opinion on the ground radioactivity as main source of air ionization, stopped German meteorologist Franz Linke to made correct conclusion on the basis of correct measurements. In fact, he made 12 balloon flights in 1900-1903 during his PhD studies at Berlin University, carrying an electroscope to a height of 5500 m. The PhD Thesis was not published, but in Thesis he concludes: "Were one to compare the presented values with those on ground, one must say that at 1000 m altitude the ionization is smaller than on the ground, between 1 and 3 km the same amount, and above it is larger with values increasing up to a factor of 4 (at 5500 m). The uncertainties in the observations only allow the conclusion that the reason for the ionization has to be found first in the Earth." Nobody later quoted Franz Linke and although he had made the right measurements, he had reached the wrong conclusions, and the discovery of CR became only later on about 10 years. 4. Victor Hess, a

  10. Progress towards a measurement of the UHE cosmic ray electron flux using the CREST Instrument

    NASA Astrophysics Data System (ADS)

    Musser, Jim; Wakely, Scott; Coutu, Stephane; Geske, Matthew; Nutter, Scott; Tarle, Gregory; Park, Nahee; Schubnell, Michael; Gennaro, Joseph; Muller, Dietrich

    2012-07-01

    Electrons of energy beyond about 3 TeV have never been detected in the flux of cosmic rays at Earth despite strong evidence of their presence in a number of supernova remnants (e.g., SN 1006). The detection of high energy electrons at Earth would be extremely significant, yielding information about the spatial distribution of nearby cosmic ray sources. With the Cosmic Ray Electron Synchrotron Telescope (CREST), our collaboration has adopted a novel approach to the detection of electrons of energies between 2 and 50 TeV which results in a substantial increase in the acceptance and sensitivity of the apparatus relative to its physics size. The first LDB flight of the CREST detector took place in January 2012, with a float duration of approximately 10 days. In this paper we describe the flight performance of the instrument, and progress in the analysis of the data obtained in this flight.

  11. Definition of parameters of daily anisotropy of cosmic rays according to the world network of neutron monitors

    NASA Astrophysics Data System (ADS)

    Grigoryev, V. G.; Starodubtsev, S. A.; Potapova, V. D.

    2013-02-01

    In our previous works we have created the method of determination of parameters of cosmic ray daily anisotropy in the interplanetary environment based on the data provided by only single station - cosmic ray spectrograph named after A.I.Kuzmin. This method allows to predict the ingress of the Earth into large-scale solar wind disturbances with a probability of more than 70% and in advance time of about from several hours up to 2 days. Now it became possible to use the data of the neutron monitor networks, which can be seen in the neutron monitor database (NMDB) in real time. In this case the well-known method of global survey is applied for determination of cosmic ray anisotropy. Usage of the data of the cosmic ray station network allows to determine parameters of daily cosmic ray anisotropy with a greater accuracy.

  12. Evaluation of Galactic Cosmic Ray Models

    NASA Technical Reports Server (NTRS)

    Adams, James H., Jr.; Heiblim, Samuel; Malott, Christopher

    2009-01-01

    Models of the galactic cosmic ray spectra have been tested by comparing their predictions to an evaluated database containing more than 380 measured cosmic ray spectra extending from 1960 to the present.

  13. Gravitational waves and cosmic strings

    NASA Astrophysics Data System (ADS)

    Siemens, Xavier

    2002-08-01

    Cosmic strings are potential candidates for a variety of interesting cosmological phenomena such as gamma ray bursts, gravitational wave bursts and ultra high energy cosmic rays. The predictions of cosmic string models, however, depend sensitively on the so far unresolved question of the size of the small-scale structure. This thesis deals largely with this problem. First, I present a gravitational back-reaction model that assumes the interaction between all Fourier modes that make up a given perturbation on a long cosmic string. This calculation leads to the generally accepted value of the small scale structure cutoff. It also, however, leads to paradoxical behaviour when applied to two oppositely moving modes: As one of the modes is stretched conformally the gravitational power radiated approaches a constant. This result is in contradiction with our expectation for the straight string limit in which no power is radiated. A more careful investigation of this problem reveals that, in the case of two oppositely moving modes, the gravitational power is exponentially suppressed when the wavelengths of the modes are sufficiently different. I use this result to construct an improved gravitational back-reaction model in which modes of very different wavelengths do not interact. This model leads to a new small scale structure cutoff which is sensitive to the initial spectrum of perturbations present on the string. I also tentatively examine the consequences of this result for the evolution of cosmic string loops. Finally, I investigate the effect of the presence of small scale structure on the gravitational wave-bursts produced at cosmic string cusps.

  14. Nonlocal Models of Cosmic Acceleration

    NASA Astrophysics Data System (ADS)

    Woodard, R. P.

    2014-02-01

    I review a class of nonlocally modified gravity models which were proposed to explain the current phase of cosmic acceleration without dark energy. Among the topics considered are deriving causal and conserved field equations, adjusting the model to make it support a given expansion history, why these models do not require an elaborate screening mechanism to evade solar system tests, degrees of freedom and kinetic stability, and the negative verdict of structure formation. Although these simple models are not consistent with data on the growth of cosmic structures many of their features are likely to carry over to more complicated models which are in better agreement with the data.

  15. Fun Times with Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Wanjek, Christopher

    2003-01-01

    Who would have thought cosmic rays could be so hip? Although discovered 90 years ago on death-defying manned balloon flights hip even by twenty-first-century extremesport standards cosmic rays quickly lost popularity as way-cool telescopes were finding way-too-cool phenomena across the electromagnetic spectrum. Yet cosmic rays are back in vogue, boasting their own set of superlatives. Scientists are tracking them down with new resolve from the Arctic to Antarctica and even on the high western plains of Argentina. Theorists, too, now see cosmic rays as harbingers of funky physics. Cosmic rays are atomic and subatomic particles - the fastest moving bits of matter in the universe and the only sample of matter we have from outside the solar system (with the exception of interstellar dust grains). Lower-energy cosmic rays come from the Sun. Mid-energy particles come from stellar explosions - either spewed directly from the star like shrapnel, or perhaps accelerated to nearly the speed of light by shock waves. The highest-energy cosmic rays, whose unequivocal existence remains one of astronomy's greatest mysteries, clock in at a staggering 10(exp 19) to 10(exp 22) electron volts. This is the energy carried in a baseball pitch; seeing as how there are as many atomic particles in a baseball as there are baseballs in the Moon, that s one powerful toss. No simple stellar explosion could produce them. At a recent conference in Albuquerque, scientists presented the first observational evidence of a possible origin for the highest-energy variety. A team led by Elihu Boldt at NASA s Goddard Space Flight Center found that five of these very rare cosmic rays (there are only a few dozen confirmed events) come from the direction of four 'retired' quasar host galaxies just above the arm of the Big Dipper, all visible with backyard telescopes: NGC 3610, NGC 3613, NGC 4589, and NGC 5322. These galaxies are billions of years past their glory days as the brightest beacons in the universe

  16. Evolution of cosmic string networks

    NASA Technical Reports Server (NTRS)

    Albrecht, Andreas; Turok, Neil

    1989-01-01

    Results on cosmic strings are summarized including: (1) the application of non-equilibrium statistical mechanics to cosmic string evolution; (2) a simple one scale model for the long strings which has a great deal of predictive power; (3) results from large scale numerical simulations; and (4) a discussion of the observational consequences of our results. An upper bound on G mu of approximately 10(-7) emerges from the millisecond pulsar gravity wave bound. How numerical uncertainties affect this are discussed. Any changes which weaken the bound would probably also give the long strings the dominant role in producing observational consequences.

  17. Special Relativity in the School Laboratory: A Simple Apparatus for Cosmic-Ray Muon Detection

    ERIC Educational Resources Information Center

    Singh, P.; Hedgeland, H.

    2015-01-01

    We use apparatus based on two Geiger-Müller tubes, a simple electronic circuit and a Raspberry Pi computer to illustrate relativistic time dilation affecting cosmic-ray muons travelling through the atmosphere to the Earth's surface. The experiment we describe lends itself to both classroom demonstration to accompany the topic of special relativity…

  18. IR lasers in a struggle against dangerous cosmic objects

    NASA Astrophysics Data System (ADS)

    Kuzyakov, Boris A.

    2001-03-01

    Humanity can struggle with the small dangerous cosmic objects in our time and its parameter knowledge are needed. A present paper deals with prospects for the perspective of the laser methods applications for a dangerous asteroids discovering and a remote sensing and for the course correction systems of the influence expedients. The cosmic IR lasers will be used for remote sensing measurement of the various cosmic objects parameters: dimensions are more than 50 m, velocity is more than 10 km/s. The laser methods have the good perspectives among a large fleet of diagnostics technical means. The more effective CO2-laser parameters were defined for the solar systems smaller bodies velocity analysis. The laser is supplied with modulated laser radiation and an automatic tuning optical system. The CO2-lidars are needed for the asteroids detections and remote sensing at the distances of 30,000 km to 1 Mkm. A laser Doppler anemometer method with adaptive selection is used. The power calculations were made for the various asteroids in a cosmic space. The possibilities are estimated for remote sensing and for the course correction systems of the influence expedients also. The such system must be good for the distances nearby 12600 km, as the asteroids velocity can be more than 70 km/s.

  19. Cosmic strings and ultra-high energy cosmic rays

    NASA Technical Reports Server (NTRS)

    Bhattacharjee, Pijushpani

    1989-01-01

    The flux is calculated of ultrahigh energy protons due to the process of cusp evaporation from cosmic string loops. For the standard value of the dimensionless cosmic string parameter epsilon is identical to G(sub mu) approx. = 10(exp -6), the flux is several orders of magnitude below the observed cosmic ray flux of ultrahigh energy protons. However, the flux at any energy initially increases as the value of epsilon is decreased. This at first suggests that there may be a lower limit on the value of epsilon, which would imply a lower limit on the temperature of a cosmic string forming phase transition in the early universe. However, the calculation shows that this is not the case -- the particle flux at any energy reaches its highest value at epsilon approx. = 10(exp -15) and it then decreases for further decrease of the value of epsilon. This is due to the fact that for too small values of epsilon (less than 10(exp -15)), the energy loss of the loops through the cusp evaporation process itself (rather than gravitational energy loss of the loops) becomes the dominant factor that controls the behavior of the number density of the loops at the relevant times of emission of the particles. The highest flux at any energy remains at least four orders of magnitude below the observed flux. There is thus no lower limit on epsilon.

  20. The Colossal Cosmic Eye

    NASA Astrophysics Data System (ADS)

    2005-09-01

    Eighty-five million years ago on small planet Earth, dinosaurs ruled, ignorant of their soon-to-come demise in the great Jurassic extinction, while mammals were still small and shy creatures. The southern Andes of Bolivia, Chile, and Argentina were not yet formed and South America was still an island continent. Eighty-five million years ago, our Sun and its solar system was 60,000 light years away from where it now stands [1]. Eighty-five million years ago, in another corner of the Universe, light left the beautiful spiral galaxy NGC 1350, for a journey across the universe. Part of this light was recorded at the beginning of the year 2000 AD by ESO's Very Large Telescope, located on the 2,600m high Cerro Paranal in the Chilean Andes on planet Earth. Astronomers classify NGC 1350 as an Sa(r) type galaxy, meaning it is a spiral with large central regions. In fact, NGC 1350 lies at the border between the broken-ring spiral type and a grand design spiral with two major outer arms. It is about 130,000 light-years across and, hence, is slightly larger than our Milky Way. The rather faint and graceful outer arms originate at the inner main ring and can be traced for almost half a circle when they each meet the opposite arm, giving the impression of completing a second outer ring, the "eye". The arms are given a blue tint as a result of the presence of very young and massive stars. The amount of dust, seen as small fragmented dust spirals in the central part of the galaxy and producing a fine tapestry that bear resemblance with blood vessels in the eye, is also a signature of the formation of stars.

  1. Cause of Cambrian Explosion - Terrestrial or Cosmic?

    PubMed

    Steele, Edward J; Al-Mufti, Shirwan; Augustyn, Kenneth A; Chandrajith, Rohana; Coghlan, John P; Coulson, S G; Ghosh, Sudipto; Gillman, Mark; Gorczynski, Reginald M; Klyce, Brig; Louis, Godfrey; Mahanama, Kithsiri; Oliver, Keith R; Padron, Julio; Qu, Jiangwen; Schuster, John A; Smith, W E; Snyder, Duane P; Steele, Julian A; Stewart, Brent J; Temple, Robert; Tokoro, Gensuke; Tout, Christopher A; Unzicker, Alexander; Wainwright, Milton; Wallis, Jamie; Wallis, Daryl H; Wallis, Max K; Wetherall, John; Wickramasinghe, D T; Wickramasinghe, J T; Wickramasinghe, N Chandra; Liu, Yongsheng

    2018-08-01

    We review the salient evidence consistent with or predicted by the Hoyle-Wickramasinghe (H-W) thesis of Cometary (Cosmic) Biology. Much of this physical and biological evidence is multifactorial. One particular focus are the recent studies which date the emergence of the complex retroviruses of vertebrate lines at or just before the Cambrian Explosion of ∼500 Ma. Such viruses are known to be plausibly associated with major evolutionary genomic processes. We believe this coincidence is not fortuitous but is consistent with a key prediction of H-W theory whereby major extinction-diversification evolutionary boundaries coincide with virus-bearing cometary-bolide bombardment events. A second focus is the remarkable evolution of intelligent complexity (Cephalopods) culminating in the emergence of the Octopus. A third focus concerns the micro-organism fossil evidence contained within meteorites as well as the detection in the upper atmosphere of apparent incoming life-bearing particles from space. In our view the totality of the multifactorial data and critical analyses assembled by Fred Hoyle, Chandra Wickramasinghe and their many colleagues since the 1960s leads to a very plausible conclusion - life may have been seeded here on Earth by life-bearing comets as soon as conditions on Earth allowed it to flourish (about or just before 4.1 Billion years ago); and living organisms such as space-resistant and space-hardy bacteria, viruses, more complex eukaryotic cells, fertilised ova and seeds have been continuously delivered ever since to Earth so being one important driver of further terrestrial evolution which has resulted in considerable genetic diversity and which has led to the emergence of mankind. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Radioresistance of Adenine to Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Vignoli Muniz, Gabriel S.; Mejía, Christian F.; Martinez, Rafael; Auge, Basile; Rothard, Hermann; Domaracka, Alicja; Boduch, Philippe

    2017-04-01

    The presence of nucleobases in carbonaceous meteorites on Earth is an indication of the existence of this class of molecules in outer space. However, space is permeated by ionizing radiation, which can have damaging effects on these molecules. Adenine is a purine nucleobase that amalgamates important biomolecules such as DNA, RNA, and ATP. Adenine has a unique importance in biochemistry and therefore life. The aim of this work was to study the effects of cosmic ray analogues on solid adenine and estimate its survival when exposed to corpuscular radiation. Adenine films were irradiated at GANIL (Caen, France) and GSI (Darmstadt, Germany) by 820 MeV Kr33+, 190 MeV Ca10+, 92 MeV Xe23+, and 12 MeV C4+ ion beams at low temperature. The evolution of adenine molecules under heavy ion irradiation was studied by IR absorption spectroscopy as a function of projectile fluence. It was found that the adenine destruction cross section (σd) follows an electronic stopping power (Se) power law under the form: CSen; C is a constant, and the exponential n is a dimensionless quantity. Using the equation above to fit our results, we determined σd = 4 × 10-17 Se1.17, with Se in kiloelectronvolts per micrometer (keV μm-1). New IR absorption bands arise under irradiation of adenine and can be attributed to HCN, CN-, C2H4N4, CH3CN, and (CH3)3CNC. These findings may help to understand the stability and chemistry related to complex organic molecules in space. The half-life of solid adenine exposed to the simulated interstellar medium cosmic ray flux was estimated as (10 ± 8) × 106 years.

  3. A Demonstration Device for Cosmic Rays Telescopes

    ERIC Educational Resources Information Center

    Esposito, Salvatore

    2018-01-01

    We describe a hands-on accurate demonstrator for cosmic rays realized by six high school students. The main aim is to show the relevance and the functioning of the principal parts of a cosmic ray telescope (muon detector), with the help of two large sized wooden artefacts. The first one points out how cosmic rays can be tracked in a muon…

  4. The microphysics and macrophysics of cosmic rays

    SciTech Connect

    Zweibel, Ellen G.

    2013-05-15

    This review paper commemorates a century of cosmic ray research, with emphasis on the plasma physics aspects. Cosmic rays comprise only ∼10{sup −9} of interstellar particles by number, but collectively their energy density is about equal to that of the thermal particles. They are confined by the Galactic magnetic field and well scattered by small scale magnetic fluctuations, which couple them to the local rest frame of the thermal fluid. Scattering isotropizes the cosmic rays and allows them to exchange momentum and energy with the background medium. I will review a theory for how the fluctuations which scatter the cosmicmore » rays can be generated by the cosmic rays themselves through a microinstability excited by their streaming. A quasilinear treatment of the cosmic ray–wave interaction then leads to a fluid model of cosmic rays with both advection and diffusion by the background medium and momentum and energy deposition by the cosmic rays. This fluid model admits cosmic ray modified shocks, large scale cosmic ray driven instabilities, cosmic ray heating of the thermal gas, and cosmic ray driven galactic winds. If the fluctuations were extrinsic turbulence driven by some other mechanism, the cosmic ray background coupling would be entirely different. Which picture holds depends largely on the nature of turbulence in the background medium.« less

  5. The Acquisition of Scientific Knowledge: The Influence of Methods of Questioning and Analysis on the Interpretation of Children's Conceptions of the Earth

    ERIC Educational Resources Information Center

    Frede, Valerie; Nobes, Gavin; Frappart, Soren; Panagiotaki, Georgia; Troadec, Bertrand; Martin, Alan

    2011-01-01

    Studies of children's knowledge of the Earth have led to very different conclusions: some appear to show that children construct their own, non-scientific "theories" (mental models) of the flat, hollow or dual Earth. Others indicate that many young children have some understanding of the spherical (scientific) Earth, and that their…

  6. A Bitter Pill: The Cosmic Lithium Problem

    NASA Astrophysics Data System (ADS)

    Fields, Brian

    2014-03-01

    Primordial nucleosynthesis describes the production of the lightest nuclides in the first three minutes of cosmic time. We will discuss the transformative influence of the WMAP and Planck determinations of the cosmic baryon density. Coupled with nucleosynthesis theory, these measurements make tight predictions for the primordial light element abundances: deuterium observations agree spectacularly with these predictions, helium observations are in good agreement, but lithium observations (in ancient halo stars) are significantly discrepant-this is the ``lithium problem.'' Over the past decade, the lithium discrepancy has become more severe, and very recently the solution space has shrunk. A solution due to new nuclear resonances has now been essentially ruled out experimentally. Stellar evolution solutions remain viable but must be finely tuned. Observational systematics are now being probed by qualitatively new methods of lithium observation. Finally, new physics solutions are now strongly constrained by the combination of the precision baryon determination by Planck, and the need to match the D/H abundances now measured to unprecedented precision at high redshift. Supported in part by NSF grant PHY-1214082.

  7. Discover Earth

    NASA Technical Reports Server (NTRS)

    Steele, Colleen

    1998-01-01

    Discover Earth is a NASA-sponsored project for teachers of grades 5-12, designed to: (1) enhance understanding of the Earth as an integrated system; (2) enhance the interdisciplinary approach to science instruction; and (3) provide classroom materials that focus on those goals. Discover Earth is conducted by the Institute for Global Environmental Strategies in collaboration with Dr. Eric Barron, Director, Earth System Science Center, The Pennsylvania State University; and Dr. Robert Hudson, Chair, the Department of Meteorology, University of Maryland at College Park. The enclosed materials: (1) represent only part of the Discover Earth materials; (2) were developed by classroom teachers who are participating in the Discover Earth project; (3) utilize an investigative approach and on-line data; and (4) can be effectively adjusted to classrooms with greater/without technology access. The Discover Earth classroom materials focus on the Earth system and key issues of global climate change including topics such as the greenhouse effect, clouds and Earth's radiation balance, surface hydrology and land cover, and volcanoes and climate change. All the materials developed to date are available on line at (http://www.strategies.org) You are encouraged to submit comments and recommendations about these materials to the Discover Earth project manager, contact information is listed below. You are welcome to duplicate all these materials.

  8. Alteration of Organic Compounds in Small Bodies and Cosmic Dusts by Cosmic Rays and Solar Radiation

    NASA Astrophysics Data System (ADS)

    Kobayashi, Kensei; Kaneko, Takeo; Mita, Hajime; Obayashi, Yumiko; Takahashi, Jun-ichi; Sarker, Palash K.; Kawamoto, Yukinori; Okabe, Takuto; Eto, Midori; Kanda, Kazuhiro

    2012-07-01

    A wide variety of complex organic compounds have been detected in extraterrestrial bodies like carbonaceous chondrites and comets, and their roles in the generation of terrestrial life are discussed. It was suggested that organics in small bodies were originally formed in ice mantles of interstellar dusts in dense cloud. Irradiation of frozen mixture of possible interstellar molecules including CO (or CH _{3}OH), NH _{3} and H _{2}O with high-energy particles gave complex amino acid precursors with high molecular weights [1]. Such complex organic molecules were taken in planetesimals or comets in the early solar system. In prior to the generation of the terrestrial life, extraterrestrial organics were delivered to the primitive Earth by such small bodies as meteorites, comets and space dusts. These organics would have been altered by cosmic rays and solar radiation (UV, X-rays) before the delivery to the Earth. We examined possible alteration of amino acids, their precursors and nucleic acid bases in interplanetary space by irradiation with high energy photons and heavy ions. A mixture of CO, NH _{3} and H _{2}O was irradiated with high-energy protons from a van de Graaff accelerator (TIT, Japan). The resulting products (hereafter referred to as CAW) are complex precursors of amino acids. CAW, amino acids (dl-Isovaline, glycine), hydantoins (amino acid precursors) and nucleic acid bases were irradiated with continuous emission (soft X-rays to IR; hereafter referred to as soft X-rays irradiation) from BL-6 of NewSUBARU synchrotron radiation facility (Univ. Hyogo). They were also irradiated with heavy ions (eg., 290 MeV/u C ^{6+}) from HIMAC accelerator (NIRS, Japan). After soft X-rays irradiation, water insoluble materials were formed. After irradiation with soft X-rays or heavy ions, amino acid precursors (CAW and hydantoins) gave higher ratio of amino acids were recovered after hydrolysis than free amino acids. Nucleic acid bases showed higher stability than free

  9. Study of the Geoeffectiveness and Galactic Cosmic-Ray Response of VarSITI-ISEST Campaign Events in Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Aslam, O. P. M.; Badruddin

    2017-09-01

    We analyze and compare the geomagnetic and galactic cosmic-ray (GCR) response of selected solar events, particularly the campaign events of the group International Study of Earth-affecting Solar Transients (ISEST) of the program Variability of the Sun and Its Terrestrial Impact (VarSITI). These selected events correspond to Solar Cycle 24, and we identified various of their features during their near-Earth passage. We evaluated the hourly data of geomagnetic indices and ground-based neutron monitors and the concurrent data of interplanetary plasma and field parameters. We recognized distinct features of these events and solar wind parameters when the geomagnetic disturbance was at its peak and when the cosmic-ray intensity was most affected. We also discuss the similarities and differences in the geoeffectiveness and GCR response of the solar and interplanetary structures in the light of plasma and field variations and physical mechanism(s), which play a crucial role in influencing the geomagnetic activity and GCR intensity.

  10. The Resurgence of Cosmic Storytellers

    ERIC Educational Resources Information Center

    Swimme, Brian

    2013-01-01

    Brian Swimme's insights about the Story of the Universe look to the unifying impact of a "cosmic story" that speaks to all cultures and nations. Swimme suggests that humans are now able, through science and narrative, to present a story which will make us all a "cohesive tribe" while answering the universal questions of…

  11. Art and the Cosmic Connection

    ERIC Educational Resources Information Center

    Cobb, Whitney H.; Aiello, Monica Petty; Macdonald, Reeves; Asplund, Shari

    2014-01-01

    The interdisciplinary unit described in this article utilizes "Art and the Cosmic Connection," a free program conceived of by artists Monica and Tyler Aiello and developed by the artists, scientists, and educators through NASA's Discovery and New Frontiers Programs, to inspire learners to explore mysterious worlds in our solar…

  12. Cosmology with the cosmic web

    NASA Astrophysics Data System (ADS)

    Forero-Romero, J. E.

    2017-07-01

    This talk summarizes different algorithms that can be used to trace the cosmic web both in simulations and observations. We present different applications in galaxy formation and cosmology. To finalize, we show how the Dark Energy Spectroscopic Instrument (DESI) could be a good place to apply these techniques.

  13. The Cosmic Ray Electron Excess

    NASA Technical Reports Server (NTRS)

    Chang, J.; Adams, J. H.; Ahn, H. S.; Bashindzhagyan, G. L.; Christl, M.; Ganel, O.; Guzik, T. G.; Isbert, J.; Kim, K. C.; Kuznetsov, E. N.; hide

    2008-01-01

    This slide presentation reviews the possible sources for the apparent excess of Cosmic Ray Electrons. The presentation reviews the Advanced Thin Ionization Calorimeter (ATIC) instrument, the various parts, how cosmic ray electrons are measured, and shows graphs that review the results of the ATIC instrument measurement. A review of Cosmic Ray Electrons models is explored, along with the source candidates. Scenarios for the excess are reviewed: Supernova remnants (SNR) Pulsar Wind nebulae, or Microquasars. Each of these has some problem that mitigates the argument. The last possibility discussed is Dark Matter. The Anti-Matter Exploration and Light-nuclei Astrophysics (PAMELA) mission is to search for evidence of annihilations of dark matter particles, to search for anti-nuclei, to test cosmic-ray propagation models, and to measure electron and positron spectra. There are slides explaining the results of Pamela and how to compare these with those of the ATIC experiment. Dark matter annihilation is then reviewed, which represent two types of dark matter: Neutralinos, and kaluza-Kline (KK) particles, which are next explained. The future astrophysical measurements, those from GLAST LAT, the Alpha Magnetic Spectrometer (AMS), and HEPCAT are reviewed, in light of assisting in finding an explanation for the observed excess. Also the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) could help by revealing if there are extra dimensions.

  14. Q&A: Cosmic gardener

    NASA Astrophysics Data System (ADS)

    Hoffman, Jascha

    2011-05-01

    Charles Jencks designs landscapes and sculptures to convey concepts in astronomy, biology and mathematics -- notably at CERN, Europe's particle-physics lab near Geneva, Switzerland, and in his Garden of Cosmic Speculation near Dumfries in Scotland, UK. On the launch of his new book, he discusses green architecture and metaphor.

  15. Cosmic Censorship for Gowdy Spacetimes.

    PubMed

    Ringström, Hans

    2010-01-01

    Due to the complexity of Einstein's equations, it is often natural to study a question of interest in the framework of a restricted class of solutions. One way to impose a restriction is to consider solutions satisfying a given symmetry condition. There are many possible choices, but the present article is concerned with one particular choice, which we shall refer to as Gowdy symmetry. We begin by explaining the origin and meaning of this symmetry type, which has been used as a simplifying assumption in various contexts, some of which we shall mention. Nevertheless, the subject of interest here is strong cosmic censorship. Consequently, after having described what the Gowdy class of spacetimes is, we describe, as seen from the perspective of a mathematician, what is meant by strong cosmic censorship. The existing results on cosmic censorship are based on a detailed analysis of the asymptotic behavior of solutions. This analysis is in part motivated by conjectures, such as the BKL conjecture, which we shall therefore briefly describe. However, the emphasis of the article is on the mathematical analysis of the asymptotics, due to its central importance in the proof and in the hope that it might be of relevance more generally. The article ends with a description of the results that have been obtained concerning strong cosmic censorship in the class of Gowdy spacetimes.

  16. BLOWING COSMIC BUBBLES

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This NASA Hubble Space Telescope image reveals an expanding shell of glowing gas surrounding a hot, massive star in our Milky Way Galaxy. This shell is being shaped by strong stellar winds of material and radiation produced by the bright star at the left, which is 10 to 20 times more massive than our Sun. These fierce winds are sculpting the surrounding material - composed of gas and dust - into the curve-shaped bubble. Astronomers have dubbed it the Bubble Nebula (NGC 7635). The nebula is 10 light-years across, more than twice the distance from Earth to the nearest star. Only part of the bubble is visible in this image. The glowing gas in the lower right-hand corner is a dense region of material that is getting blasted by radiation from the Bubble Nebula's massive star. The radiation is eating into the gas, creating finger-like features. This interaction also heats up the gas, causing it to glow. Scientists study the Bubble Nebula to understand how hot stars interact with the surrounding material. Credit: Hubble Heritage Team (AURA/STScI/NASA)

  17. Cosmic Fairy Lights

    NASA Image and Video Library

    2014-04-25

    This sparkling jumble is Messier 5 — a globular cluster consisting of hundreds of thousands of stars bound together by their collective gravity. But Messier 5 is no normal globular cluster. At 13 billion years old it dates back to close to the beginning of the Universe, which is some 13.8 billion years of age. It is also one of the biggest clusters known, and at only 24 500 light-years away, it is no wonder that Messier 5 is a popular site for astronomers to train their telescopes on. Messier 5 also presents a puzzle. Stars in globular clusters grow old and wise together. So Messier 5 should, by now, consist of old, low-mass red giants and other ancient stars. But it is actually teeming with young blue stars known as blue stragglers. These stars spring to life when stars collide, or rip material from one another. Credit: ESA/NASA NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  18. Astronomers Unveiling Life's Cosmic Origins

    NASA Astrophysics Data System (ADS)

    2009-02-01

    Processes that laid the foundation for life on Earth -- star and planet formation and the production of complex organic molecules in interstellar space -- are yielding their secrets to astronomers armed with powerful new research tools, and even better tools soon will be available. Astronomers described three important developments at a symposium on the "Cosmic Cradle of Life" at the annual meeting of the American Association for the Advancement of Science in Chicago, IL. Chemistry Cycle The Cosmic Chemistry Cycle CREDIT: Bill Saxton, NRAO/AUI/NSF Full Size Image Files Chemical Cycle Graphic (above image, JPEG, 129K) Graphic With Text Blocks (JPEG, 165K) High-Res TIFF (44.2M) High-Res TIFF With Text Blocks (44.2M) In one development, a team of astrochemists released a major new resource for seeking complex interstellar molecules that are the precursors to life. The chemical data released by Anthony Remijan of the National Radio Astronomy Observatory (NRAO) and his university colleagues is part of the Prebiotic Interstellar Molecule Survey, or PRIMOS, a project studying a star-forming region near the center of our Milky Way Galaxy. PRIMOS is an effort of the National Science Foundation's Center for Chemistry of the Universe, started at the University of Virginia (UVa) in October 2008, and led by UVa Professor Brooks H. Pate. The data, produced by the NSF's Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, came from more than 45 individual observations totalling more than nine GigaBytes of data and over 1.4 million individual frequency channels. Scientists can search the GBT data for specific radio frequencies, called spectral lines -- telltale "fingerprints" -- naturally emitted by molecules in interstellar space. "We've identified more than 720 spectral lines in this collection, and about 240 of those are from unknown molecules," Remijan said. He added, "We're making available to all scientists the best collection of data below 50 GHz ever produced for

  19. Hubble Gazes at a Cosmic Megamaser

    NASA Image and Video Library

    2017-12-08

    This galaxy has a far more exciting and futuristic classification than most — it hosts a megamaser. Megamasers are intensely bright, around 100 million times brighter than the masers found in galaxies like the Milky Way. The entire galaxy essentially acts as an astronomical laser that beams out microwave emission rather than visible light (hence the ‘m’ replacing the ‘l’). A megamaser is a process that involves some components within the galaxy (like gas) that is in the right physical condition to cause the amplification of light (in this case, microwaves). But there are other parts of the galaxy (like stars for example) that aren’t part of the maser process. This megamaser galaxy is named IRAS 16399-0937 and is located over 370 million light-years from Earth. This NASA/ESA Hubble Space Telescope image belies the galaxy’s energetic nature, instead painting it as a beautiful and serene cosmic rosebud. The image comprises observations captured across various wavelengths by two of Hubble’s instruments: the Advanced Camera for Surveys (ACS), and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS). NICMOS’s superb sensitivity, resolution, and field of view gave astronomers the unique opportunity to observe the structure of IRAS 16399-0937 in detail. They found it hosts a double nucleus — the galaxy’s core is thought to be formed of two separate cores in the process of merging. The two components, named IRAS 16399N and IRAS 16399S for the northern and southern parts respectively, sit over 11,000 light-years apart. However, they are both buried deep within the same swirl of cosmic gas and dust and are interacting, giving the galaxy its peculiar structure. The nuclei are very different. IRAS 16399S appears to be a starburst region, where new stars are forming at an incredible rate. IRAS 16399N, however, is something known as a LINER nucleus (Low Ionization Nuclear Emission Region), which is a region whose emission mostly stems from weakly

  20. Cosmic ray intensity gradients in the solar system

    NASA Technical Reports Server (NTRS)

    Mckibben, R. B.

    1975-01-01

    Recent progress in the determination of cosmic-ray intensity gradients is reviewed. Direct satellite measurements of the integral gradient are described together with various types of indirect measurements, including measurements of the Ar-37/Ar-39 ratio in samples from the Lost City meteorite, studies of anisotropies in neutron-monitor counting rates, and analysis of the sidereal diurnal anisotropy observed at a single point on earth. Nucleonic radial gradients and electron gradients measured by satellites in differential energy windows are discussed, and theoretical studies of the physical processes involved in these gradients are summarized. Observations of intensity gradients in heliographic latitude are reported.

  1. Amplitudes of solar modulation of low energy cosmic rays

    NASA Technical Reports Server (NTRS)

    Von Rosenvinge, T. T.; Paizis, C.

    1982-01-01

    There have been differences of opinion regarding the origin and behavior of the solar modulation of galactic cosmic rays. It has been shown that the return to solar maximum intensity levels beginning in early 1978 was dominated by Forbush decreases. These Forbush decreases were caused by radially moving interplanetary shocks resulting from large solar flares. The present investigation is concerned with solar modulation effects which were observed during the previous solar minimum. The effects were associated with high-speed streams in the solar wind. These streams caused the formation of corotating interaction regions with both forward and reverse shocks. The modulation effects seen near earth are intimately connected with these shocks.

  2. Research in cosmic and gamma ray astrophysics

    NASA Technical Reports Server (NTRS)

    Stone, Edward C.; Mewaldt, Richard A.; Prince, Thomas A.

    1992-01-01

    Discussed here is research in cosmic ray and gamma ray astrophysics at the Space Radiation Laboratory (SRL) of the California Institute of Technology. The primary activities discussed involve the development of new instrumentation and techniques for future space flight. In many cases these instrumentation developments were tested in balloon flight instruments designed to conduct new investigations in cosmic ray and gamma ray astrophysics. The results of these investigations are briefly summarized. Specific topics include a quantitative investigation of the solar modulation of cosmic ray protons and helium nuclei, a study of cosmic ray positron and electron spectra in interplanetary and interstellar space, the solar modulation of cosmic rays, an investigation of techniques for the measurement and interpretation of cosmic ray isotopic abundances, and a balloon measurement of the isotopic composition of galactic cosmic ray boron, carbon, and nitrogen.

  3. Evaluating Galactic Cosmic Ray Environment Models Using RaD-X Flight Data

    NASA Technical Reports Server (NTRS)

    Norman, R. B.; Mertens, C. J.; Slaba, T. C.

    2016-01-01

    Galactic cosmic rays enter Earth's atmosphere after interacting with the geomagnetic field. The primary galactic cosmic rays spectrum is fundamentally changed as it interacts with Earth's atmosphere through nuclear and atomic interactions. At points deeper in the atmosphere, such as at airline altitudes, the radiation environment is a combination of the primary galactic cosmic rays and the secondary particles produced through nuclear interactions. The RaD-X balloon experiment measured the atmospheric radiation environment above 20 km during 2 days in September 2015. These experimental measurements were used to validate and quantify uncertainty in physics-based models used to calculate exposure levels for commercial aviation. In this paper, the Badhwar-O'Neill 2014, the International Organization for Standardization 15390, and the German Aerospace Company galactic cosmic ray environment models are used as input into the same radiation transport code to predict and compare dosimetric quantities to RaD-X measurements. In general, the various model results match the measured tissue equivalent dose well, with results generated by the German Aerospace Center galactic cosmic ray environment model providing the best comparison. For dose equivalent and dose measured in silicon, however, the models were compared less favorably to the measurements.

  4. COSMIC-RAY SMALL-SCALE ANISOTROPIES AND LOCAL TURBULENT MAGNETIC FIELDS

    SciTech Connect

    López-Barquero, V.; Farber, R.; Xu, S.

    2016-10-10

    Cosmic-ray anisotropy has been observed in a wide energy range and at different angular scales by a variety of experiments over the past decade. However, no comprehensive or satisfactory explanation has been put forth to date. The arrival distribution of cosmic rays at Earth is the convolution of the distribution of their sources and of the effects of geometry and properties of the magnetic field through which particles propagate. It is generally believed that the anisotropy topology at the largest angular scale is adiabatically shaped by diffusion in the structured interstellar magnetic field. On the contrary, the medium- and small-scalemore » angular structure could be an effect of nondiffusive propagation of cosmic rays in perturbed magnetic fields. In particular, a possible explanation for the observed small-scale anisotropy observed at the TeV energy scale may be the effect of particle propagation in turbulent magnetized plasmas. We perform numerical integration of test particle trajectories in low- β compressible magnetohydrodynamic turbulence to study how the cosmic rays’ arrival direction distribution is perturbed when they stream along the local turbulent magnetic field. We utilize Liouville’s theorem for obtaining the anisotropy at Earth and provide the theoretical framework for the application of the theorem in the specific case of cosmic-ray arrival distribution. In this work, we discuss the effects on the anisotropy arising from propagation in this inhomogeneous and turbulent interstellar magnetic field.« less

  5. A predictive analytic model for the solar modulation of cosmic rays

    DOE PAGES

    Cholis, Ilias; Hooper, Dan; Linden, Tim

    2016-02-23

    An important factor limiting our ability to understand the production and propagation of cosmic rays pertains to the effects of heliospheric forces, commonly known as solar modulation. The solar wind is capable of generating time- and charge-dependent effects on the spectrum and intensity of low-energy (≲10 GeV) cosmic rays reaching Earth. Previous analytic treatments of solar modulation have utilized the force-field approximation, in which a simple potential is adopted whose amplitude is selected to best fit the cosmic-ray data taken over a given period of time. Making use of recently available cosmic-ray data from the Voyager 1 spacecraft, along withmore » measurements of the heliospheric magnetic field and solar wind, we construct a time-, charge- and rigidity-dependent model of solar modulation that can be directly compared to data from a variety of cosmic-ray experiments. Here, we provide a simple analytic formula that can be easily utilized in a variety of applications, allowing us to better predict the effects of solar modulation and reduce the number of free parameters involved in cosmic-ray propagation models.« less

  6. A high-resolution study of ultra-heavy cosmic-ray nuclei (A0178)

    NASA Technical Reports Server (NTRS)

    Osullivan, D.; Thompson, A.; Oceallaigh, C.; Domingo, V.; Wenzel, K. P.

    1984-01-01

    The main objective of the experiment is a detailed study of the charge spectra of ultraheavy cosmic-ray nuclei from zinc (Z = 30) to uranium (Z = 92) and beyond using solid-state track detectors. Special emphasis will be placed on the relative abundances in the region Z or - 65, which is thought to be dominated by r-process nucleosynthesis. Subsidiary objectives include the study of the cosmic-ray transiron spectrum a search for the postulated long-lived superheavy (SH) nuclei (Z or = 110), such as (110) SH294, in the contemporary cosmic radiation. The motivation behind the search for super-heavy nuclei is based on predicted half-lives that are short compared to the age of the Earth but long compared to the age of cosmic rays. The detection of such nuclei would have far-reaching consequences for nuclear structure theory. The sample of ultraheavy nuclei obtained in this experiment will provide unique opportunities for many tests concerning element nucleosynthesis, cosmic-ray acceleration, and cosmic-ray propagation.

  7. Primary gamma rays. [resulting from cosmic ray interaction with interstellar matter

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.

    1974-01-01

    Within this galaxy, cosmic rays reveal their presence in interstellar space and probably in source regions by their interactions with interstellar matter which lead to gamma rays with a very characteristic energy spectrum. From the study of the intensity of the high energy gamma radiation as a function of galactic longitude, it is already clear that cosmic rays are almost certainly not uniformly distributed in the galaxy and are not concentrated in the center of the galaxy. The galactic cosmic rays appear to be tied to galactic structural features, presumably by the galactic magnetic fields which are in turn held by the matter in the arm segments and the clouds. On the extragalactic scale, it is now possible to say that cosmic rays are not universal at the density seen near the earth. The diffuse celestial gamma ray spectrum that is observed presents the interesting possibility of cosmological studies and possible evidence for a residual universal cosmic ray density, which is much lower than the present galactic cosmic ray density.

  8. Extrapolating cosmic ray variations and impacts on life: Morlet wavelet analysis

    NASA Astrophysics Data System (ADS)

    Zarrouk, N.; Bennaceur, R.

    2009-07-01

    Exposure to cosmic rays may have both a direct and indirect effect on Earth's organisms. The radiation may lead to higher rates of genetic mutations in organisms, or interfere with their ability to repair DNA damage, potentially leading to diseases such as cancer. Increased cloud cover, which may cool the planet by blocking out more of the Sun's rays, is also associated with cosmic rays. They also interact with molecules in the atmosphere to create nitrogen oxide, a gas that eats away at our planet's ozone layer, which protects us from the Sun's harmful ultraviolet rays. On the ground, humans are protected from cosmic particles by the planet's atmosphere. In this paper we give estimated results of wavelet analysis from solar modulation and cosmic ray data incorporated in time-dependent cosmic ray variation. Since solar activity can be described as a non-linear chaotic dynamic system, methods such as neural networks and wavelet methods should be very suitable analytical tools. Thus we have computed our results using Morlet wavelets. Many have used wavelet techniques for studying solar activity. Here we have analysed and reconstructed cosmic ray variation, and we have better depicted periods or harmonics other than the 11-year solar modulation cycles.

  9. Earth Wisdom.

    ERIC Educational Resources Information Center

    Van Matre, Steve

    1985-01-01

    In our human-centered ignorance and arrogance we are rapidly destroying the earth. We must start helping people understand the big picture of ecological concepts. What these concepts mean for our own lives and how we must begin to change our lifestyles in order to live more harmoniously with the earth. (JHZ)

  10. Earth Science

    NASA Image and Video Library

    1976-01-01

    The LAGEOS I (Laser Geodynamics Satellite) was developed and launched by the Marshall Space Flight Center on May 4, 1976 from Vandenberg Air Force Base, California . The two-foot diameter satellite orbited the Earth from pole to pole and measured the movements of the Earth's surface.

  11. Cosmic vacuum energy decay and creation of cosmic matter.

    PubMed

    Fahr, Hans-Jörg; Heyl, Michael

    2007-09-01

    In the more recent literature on cosmological evolutions of the universe, the cosmic vacuum energy has become a nonrenouncable ingredient. The cosmological constant Lambda, first invented by Einstein, but later also rejected by him, presently experiences an astonishing revival. Interestingly enough, it acts like a constant vacuum energy density would also do. Namely, it has an accelerating action on cosmic dynamics, without which, as it appears, presently obtained cosmological data cannot be conciliated with theory. As we are going to show in this review, however, the concept of a constant vacuum energy density is unsatisfactory for very basic reasons because it would claim for a physical reality that acts upon spacetime and matter dynamics without itself being acted upon by spacetime or matter.

  12. Research in cosmic and gamma ray astrophysics: Cosmic physics portion

    NASA Technical Reports Server (NTRS)

    Stone, Edward C.; Mewaldt, Richard A.; Schindler, Stephen

    1993-01-01

    Research in particle astrophysics at the Space Radiation Laboratory (SRL) of the California Institute of Technology is supported under NASA Grant NAGW-1919. A three-year proposal for continuation of support was submitted a year ago and put into effect 1 October 1992. This report is the combined progress report and continuation application called for under the Federal Demonstration Project. Gamma-ray Astrophysics at SRL is separately supported under NAGW-1919 and will be separately summarized and proposed. This report will document progress and plans for our particle spectroscopy activities and for related data analysis, calibration, and community service activities. A bibliography and a budget will be attached as appendices. The Caltech SRL research program includes a heavy emphasis on elemental and isotopic spectroscopy of energetic particles in the cosmic radiation; in solar, interplanetary, and anomalous 'cosmic' radiation; and in planetary magnetospheres as discussed.

  13. Preliminary Evaluation of Influence of Aerosols on the Simulation of Brightness Temperature in the NASA's Goddard Earth Observing System Atmospheric Data Assimilation System

    NASA Technical Reports Server (NTRS)

    Kim, Jong; Akella, Santha; da Silva, Arlindo M.; Todling, Ricardo; McCarty, William

    2018-01-01

    This document reports on preliminary results obtained when studying the impact of aerosols on the calculation of brightness temperature (BT) for satellite infrared (IR) instruments that are currently assimilated in a 3DVAR configuration of Goddard Earth Observing System (GEOS)-atmospheric data assimilation system (ADAS). A set of fifteen aerosol species simulated by the Goddard Chemistry Aerosol Radiation and Transport (GOCART) model is used to evaluate the influence of the aerosol fields on the Community Radiative Transfer Model (CRTM) calculations taking place in the observation operators of the Gridpoint Statistical Interpolation (GSI) analysis system of GEOSADAS. Results indicate that taking aerosols into account in the BT calculation improves the fit to observations over regions with significant amounts of dust. The cooling effect obtained with the aerosol-affected BT leads to a slight warming of the analyzed surface temperature (by about 0:5oK) in the tropical Atlantic ocean (off northwest Africa), whereas the effect on the air temperature aloft is negligible. In addition, this study identifies a few technical issues to be addressed in future work if aerosol-affected BT are to be implemented in reanalysis and operational settings. The computational cost of applying CRTM aerosol absorption and scattering options is too high to justify their use, given the size of the benefits obtained. Furthermore, the differentiation between clouds and aerosols in GSI cloud detection procedures needs satisfactory revision.

  14. Quantification of seasonal biomass effects on cosmic-ray soil water content determination

    NASA Astrophysics Data System (ADS)

    Baatz, R.; Bogena, H. R.; Hendricks Franssen, H.; Huisman, J. A.; Qu, W.; Montzka, C.; Korres, W.; Vereecken, H.

    2013-12-01

    The novel cosmic-ray soil moisture probes (CRPs) measure neutron flux density close to the earth surface. High energy cosmic-rays penetrate the Earth's atmosphere from the cosmos and become moderated by terrestrial nuclei. Hydrogen is the most effective neutron moderator out of all chemical elements. Therefore, neutron flux density measured with a CRP at the earth surface correlates inversely with the hydrogen content in the CRP's footprint. A major contributor to the amount of hydrogen in the sensor's footprint is soil water content. The ability to measure changes in soil water content within the CRP footprint at a larger-than-point scale (~30 ha) and at high temporal resolution (hourly) make these sensors an appealing measurement instrument for hydrologic modeling purposes. Recent developments focus on the identification and quantification of major uncertainties inherent in CRP soil moisture measurements. In this study, a cosmic-ray soil moisture network for the Rur catchment in Western Germany is presented. It is proposed to correct the measured neutron flux density for above ground biomass yielding vegetation corrected soil water content from cosmic-ray measurements. The correction for above ground water equivalents aims to remove biases in soil water content measurements on sites with high seasonal vegetation dynamics such as agricultural fields. Above ground biomass is estimated as function of indices like NDVI and NDWI using regression equations. The regression equations were obtained with help of literature information, ground-based control measurements, a crop growth model and globally available data from the Moderate Resolution Imaging Spectrometer (MODIS). The results show that above ground biomass could be well estimated during the first half of the year. Seasonal changes in vegetation water content yielded biases in soil water content of ~0.05 cm3/cm3 that could be corrected for with the vegetation correction. The vegetation correction has particularly

  15. The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations

    PubMed Central

    Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

    2018-01-01

    For over 20 years, the term ‘cosmic web’ has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile ‘spiderwebs’ is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos. PMID:29765637

  16. Tidal Locking Of The Earth

    NASA Astrophysics Data System (ADS)

    Koohafkan, Michael

    2006-05-01

    The Moon's orbit and spin period are nearly synchronized, or tidally locked. Could the Moon's orbit and the Earth's spin eventually synchronize as well? The Moon's gravitational pull on the Earth produces tides in our oceans, and tidal friction gradually lengthens our days. Less obvious gravitational interactions between the Earth and Moon may also have effects on Earth's spin. The Earth is slightly distorted into an egg-like shape, and the torque exerted by the Moon on our equatorial bulge slowly changes the tilt of our spin axis. How do effects such as these change as the Moon drifts away from Earth? I will examine gravitational interactions between Earth and Moon to learn how they contribute to the deceleration of the Earth's rotation. My goal is to determine the amount of time it would take for the Earth's rotational speed to decelerate until the period of a single rotation matches the period of the Moon's orbit around Earth -- when the Earth is ``tidally locked'' with the Moon. I aim to derive a general mathematical expression for the rotational deceleration of the Earth due to Moon's gravitational influences.

  17. Cosmic Journeys: To the Edge of Gravity, Space, and Time ...

    NASA Technical Reports Server (NTRS)

    Wanjek, Christopher

    2000-01-01

    We are embarking upon a cosmic journey. From the safety of our home planet Earth, scientists plan to explore the very limits of the known Universe. Our travels will take us to where space and time cease to exist as we know them, and to where the secrets of the past and future lie captured in the starlight of the present across an expanse of billions of light-years. Cosmic Journeys, a new series of NASA space science missions, will take us to the limits of gravity, space, and time. This virtual journey will use the power of resolution far greater than what current telescopes can muster to transport us to the rim of a black hole, to eagle-eye views of the galaxies and voids that pervade the Universe, and to the earliest moments of time, just fractions of a second after the Big Bang. The goal of our Cosmic Journeys is to solve the mystery of gravity, a force that is all around us but cannot be seen.

  18. Milagro Contributions to XXVI International Cosmic Ray Conference

    SciTech Connect

    Hoffman, C.M.; Haines, T.J.; Sinnis, G.

    1999-08-01

    Milagrito, a prototype for the Milagro detector, operated for 15 months in 1997--8 and collected 8.9 x 10{sup 9} events. It was the first extensive air shower (EAS) array sensitive to showers initiated by primaries with energy below 1 TeV. The shadows of the sun and moon observed with cosmic rays can be used to study systematic pointing shifts and measure the angular resolution of EAS arrays. Below a few TeV, the paths of cosmic rays coming toward the earth are bent by the helio- and geo-magnetic fields. This is expected to distort and displace the shadows of the sunmore » and the moon. The moon shadow, offset from the nominal (unreflected) position, has been observed with high statistical significance in Milagrito. This can be used to establish energy calibrations, as well as to search for the anti-matter content of the VHE cosmic ray flux. The shadow of the sun has also been observed with high significance.« less

  19. Cosmic Flasher Reveals All!

    NASA Astrophysics Data System (ADS)

    1998-09-01

    For more information on magnetars and soft gamma-ray repeaters, see the Background Information which includes a "movie" of the flashing magnetar nebula, as seen by the VLA. Astronomers have found evidence for the most powerful magnetic field ever seen in the universe. They found it by observing a long-sought, short-lived "afterglow" of subatomic particles ejected from a magnetar -- a neutron star with a magnetic field billions of times stronger than any on Earth and 100 times stronger than any other previously known in the Universe. The afterglow is believed to be the aftermath of a massive starquake on the neutron star's surface. "And where there's smoke, there's fire, and we've seen the 'smoke' that tells us there's a magnetar out there," says Dale Frail, who used the National Science Foundation's Very Large Array (VLA) radio telescope to make the discovery. "Nature has created a unique laboratory where there are magnetic fields far stronger than anything that can be created here on Earth. As a result, the study of these objects enables us to study the effects of extraordinarily intense magnetic fields on matter," explains Dr. Morris L. Aizenman, Executive Officer in the Division of Astronomy at the National Science Foundation. Frail, an astronomer at the National Radio Astronomy Observatory (NRAO) in Socorro, New Mexico, along with Shri Kulkarni and Josh Bloom, astronomers at Caltech, discovered radio emission coming from a strange object 15,000 light-years away in our own Milky Way Galaxy. The radio emission was seen after the object experienced an outburst of gamma-rays and X-rays in late August. "This emission comes from particles ejected at nearly the speed of light from the surface of the neutron star interacting with the extremely powerful magnetic field," said Kulkarni. This is the first time this phenomenon, predicted by theorists, has been seen so clearly from a suspected magnetar. "Magnetars are expected to behave in certain ways. Astronomers have seen

  20. Towards understanding the nature of any relationship between Solar Activity and Cosmic Rays with thunderstorm activity and lightning discharge

    NASA Astrophysics Data System (ADS)

    O'Regan, J.; Muller, J.-P.; Matthews, S.

    2012-04-01

    The runaway breakdown hypothesis of lightning discharge has predicted relationships between cosmic rays' interactions with the atmosphere and thunderstorm production and lightning activity. Precipitating energetic particles lead to the injection of MeV-energy electrons into electrified thunderclouds [1,2], resulting in runaway breakdown occurring, and assisting in the process of charge separation [2]. Previous lightning studies show that correlations to solar activity are weak but significant, with better correlations to solar activity and cosmic rays when carried out over smaller geographical areas [3,4,5,6] and over longer timescales [6]. In this work, correlations are explored between variations of SEPs and lightning activity levels at various spatio-temporal scales. Temporal scales span from short-term (days) scales surrounding large Earth-directed coronal mass ejection (CME) events to long-term (years) scales. Similarly, spatial scales span from 1-degree x 1-degree latitudinal-longitudinal grid scales to an entirely global study, for varying timescales. Additionally, investigation of correlation sign and statistical significance by 1-degree latitudinal bands is also employed, allowing a comparative study of lightning activity relative to regions of greatest - and contrasting regions of relative absence of - energetic particle precipitation. These regions are determined from electron and proton flux maps, derived from measurements from the Medium Energy Proton and Electron Detector (MEPED) onboard the Polar Orbiting Environmental Satellite (POES) system. Lightning data is obtained from the World Wide Lightning Location Network (WWLLN) for the period 2005 to 2011. The correlations of lightning strike rates are carried out with respect to Relative Sunspot Number (R), 10.7cm Solar radio flux (F10.7), Galactic Cosmic Ray (GCR) neutron monitor flux, the Ap geomagnetic activity index, and Disturbance Storm Time (DST) index. Correlations show dramatic variations in

  1. Calculation of Cosmic Ray Induced Single Event Upsets: Program CRUP, Cosmic Ray Upset Program

    DTIC Science & Technology

    1983-09-14

    1.., 0 .j ~ u M ~ t R A’- ~~ ’ .~ ; I .: ’ 1 J., ) ’- CALCULATION OF COSMIC RAY INDUCED SINGLE EVEI’o"T UPSETS: PROGRAM CRUP , COSMIC RAY UPSET...neceuety end Identity by blo..;k number) 0Thls report documents PROGR.Al\\1 CRUP , COSMIC RAY UPSET PROGRAM. The computer program calculates cosmic...34. » » •-, " 1 » V »1T"~ Calculation of Cosmic Ray Induced Single Event Upsets: PROGRAM CRUP , COSMIC RAY UPSET PROGRAM I. INTRODUCTION Since the

  2. Thermal evolution of the earth

    NASA Technical Reports Server (NTRS)

    Spohn, T.

    1984-01-01

    The earth's heat budget and models of the earth's thermal evolution are discussed. Sources of the planetary heat are considered and modes of heat transport are addressed, including conduction, convection, and chemical convection. Thermal and convectional models of the earth are covered, and models of thermal evolution are discussed in detail, including changes in the core, the influence of layered mantle convection on the thermal evolution, and the effect of chemical differentiation on the continents.

  3. Placers of cosmic dust in the blue ice lakes of Greenland

    NASA Technical Reports Server (NTRS)

    Maurette, M.; Hammer, C.; Reeh, N.; Brownlee, D. E.; Thomsen, H. H.

    1986-01-01

    A concentration process occurring in the melt zone of the Greenland ice cap has produced the richest known deposit of cosmic dust on the surface of the earth. Extraterrestrial particles collected from this region are well preserved and are collectable in large quantities. The collected particles are generally identical to cosmic spheres found on the ocean floor, but a pure glass type was discovered that has not been seen in deep-sea samples. Iron-rich spheres are conspicuously rare in the collected material.

  4. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Panelists pose for a group photo at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and highlighted how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  5. Aligned interactions in cosmic rays

    SciTech Connect

    Kempa, J., E-mail: kempa@pw.plock.pl

    2015-12-15

    The first clean Centauro was found in cosmic rays years many ago at Mt Chacaltaya experiment. Since that time, many people have tried to find this type of interaction, both in cosmic rays and at accelerators. But no one has found a clean cases of this type of interaction.It happened finally in the last exposure of emulsion at Mt Chacaltaya where the second clean Centauro has been found. The experimental data for both the Centauros and STRANA will be presented and discussed in this paper. We also present our comments to the intriguing question of the existence of a typemore » of nuclear interactions at high energy with alignment.« less

  6. Cosmic Ray research in Armenia

    NASA Astrophysics Data System (ADS)

    Chilingarian, A.; Mirzoyan, R.; Zazyan, M.

    2009-11-01

    Cosmic Ray research on Mt. Aragats began in 1934 with the measurements of East-West anisotropy by the group from Leningrad Physics-Technical Institute and Norair Kocharian from Yerevan State University. Stimulated by the results of their experiments in 1942 Artem and Abraham Alikhanyan brothers organized a scientific expedition to Aragats. Since that time physicists were studying Cosmic Ray fluxes on Mt. Aragats with various particle detectors: mass spectrometers, calorimeters, transition radiation detectors, and huge particle detector arrays detecting protons and nuclei accelerated in most violent explosions in Galaxy. Latest activities at Mt. Aragats include Space Weather research with networks of particle detectors located in Armenia and abroad, and detectors of Space Education center in Yerevan.

  7. Distributed reacceleration of cosmic rays

    NASA Technical Reports Server (NTRS)

    Wandel, Amri; Eichler, David; Letaw, John R.; Silberberg, Rein; Tsao, C. H.

    1985-01-01

    A model is developed in which cosmic rays, in addition to their initial acceleration by a strong shock, are continuously reaccelerated while propagating through the Galaxy. The equations describing this acceleration scheme are solved analytically and numerically. Solutions for the spectra of primary and secondary cosmic rays are given in a closed analytic form, allowing a rapid search in parameter space for viable propagation models with distributed reeacceleration included. The observed boron-to-carbon ratio can be reproduced by the reacceleration theory over a range of escape parameters, some of them quite different from the standard leaky-box model. It is also shown that even a very modest amount of reacceleration by strong shocks causes the boron-to-carbon ratio to level off at sufficiently high energies.

  8. Cosmic censorship in Lovelock theory

    NASA Astrophysics Data System (ADS)

    Camanho, Xián O.; Edelstein, José D.

    2013-11-01

    In analyzing maximally symmetric Lovelock black holes with non-planar horizon topologies, many novel features have been observed. The existence of finite radius singularities, a mass gap in the black hole spectrum and solutions displaying multiple horizons are noteworthy examples. Naively, in all these cases, the appearance of naked singularities seems unavoidable, leading to the question of whether these theories are consistent gravity theories. We address this question and show that whenever the cosmic censorship conjecture is threaten, an instability generically shows up driving the system to a new configuration with presumably no naked singularities. Also, the same kind of instability shows up in the process of spherical black holes evaporation in these theories, suggesting a new phase for their decay. We find circumstantial evidence indicating that, contrary to many claims in the literature, the cosmic censorship hypothesis holds in Lovelock theory.

  9. Evolution of the Cosmic Web

    NASA Astrophysics Data System (ADS)

    Einasto, J.

    2017-07-01

    In the evolution of the cosmic web dark energy plays an important role. To understand the role of dark energy we investigate the evolution of superclusters in four cosmological models: standard model SCDM, conventional model LCDM, open model OCDM, and a hyper-dark-energy model HCDM. Numerical simulations of the evolution are performed in a box of size 1024 Mpc/h. Model superclusters are compared with superclusters found for Sloan Digital Sky Survey (SDSS). Superclusters are searched using density fields. LCDM superclusters have properties, very close to properties of observed SDSS superclusters. Standard model SCDM has about 2 times more superclusters than other models, but SCDM superclusters are smaller and have lower luminosities. Superclusters as principal structural elements of the cosmic web are present at all cosmological epochs.

  10. Characterising CCDs with cosmic rays

    DOE PAGES

    Fisher-Levine, M.; Nomerotski, A.

    2015-08-06

    The properties of cosmic ray muons make them a useful probe for measuring the properties of thick, fully depleted CCD sensors. The known energy deposition per unit length allows measurement of the gain of the sensor's amplifiers, whilst the straightness of the tracks allows for a crude assessment of the static lateral electric fields at the sensor's edges. The small volume in which the muons deposit their energy allows measurement of the contribution to the PSF from the diffusion of charge as it drifts across the sensor. In this work we present a validation of the cosmic ray gain measurementmore » technique by comparing with radioisotope gain measurments, and calculate the charge diffusion coefficient for prototype LSST sensors.« less

  11. Voyager measurements of the isotopic composition of cosmic-ray aluminum and implications for the propagation of cosmic rays

    NASA Technical Reports Server (NTRS)

    Lukasiak, A.; Mcdonald, F. B.; Webber, W. R.

    1994-01-01

    We report a new measurement of the cosmic-ray isotopic composition of aluminum in the low-energy range form 75 to 206 MeV per nucleon.This measurement was made using the high-energy telescope of the CRS experiment on the Voyager 1 and 2 spacecraft during the time period from 1977 to 1993 with an average solar modulation level about 497 MV, roughly the same as at Earth near sunspot minimum. We obtain approximately 430 Al events of which approximately 35 are Al-26 and 395 are Al-27. The Al isotopes were separated with an average mass resolution sigma of 0.35 amu. Our interpretation of the isotopic composition of cosmic-ray aluminum is based on a standard Leaky-Box model for the interstellar propagation of cosmic-ray nuclei using the latest cross sections of the New Mexico-Saclay collaboration as well as a disk-halo diffusion model. From our observed ratio Al-26/Al-27 of 8.3 +/- 2.4 % we deduce an average interstellar density of about 0.52 (+0.26, -0.2) atoms per cu cm. This density is larger than the value of 0.28 (+0.14, -0.11) atoms per cu cm we found from an analysis of the observed abundance of the longer lived Be-10 made using data from the Voyager detectors over almost the same time interval and using essentially the same propagation program.

  12. From cosmic ray physics to cosmic ray astronomy: Bruno Rossi and the opening of new windows on the universe

    NASA Astrophysics Data System (ADS)

    Bonolis, Luisa

    2014-01-01

    Bruno Rossi is considered one of the fathers of modern physics, being also a pioneer in virtually every aspect of what is today called high-energy astrophysics. At the beginning of 1930s he was the pioneer of cosmic ray research in Italy, and, as one of the leading actors in the study of the nature and behavior of the cosmic radiation, he witnessed the birth of particle physics and was one of the main investigators in this fields for many years. While cosmic ray physics moved more and more towards astrophysics, Rossi continued to be one of the inspirers of this line of research. When outer space became a reality, he did not hesitate to leap into this new scientific dimension. Rossi's intuition on the importance of exploiting new technological windows to look at the universe with new eyes, is a fundamental key to understand the profound unity which guided his scientific research path up to its culminating moments at the beginning of 1960s, when his group at MIT performed the first in situ measurements of the density, speed and direction of the solar wind at the boundary of Earth's magnetosphere, and when he promoted the search for extra-solar sources of X rays. A visionary idea which eventually led to the breakthrough experiment which discovered Scorpius X-1 in 1962, and inaugurated X-ray astronomy.

  13. Charged Cosmic Rays and Neutrinos

    NASA Astrophysics Data System (ADS)

    Kachelrieß, M.

    2013-04-01

    High-energy neutrino astronomy has grown up, with IceCube as one of its main experiments having sufficient sensitivity to test "vanilla" models of astrophysical neutrinos. I review predictions of neutrino fluxes as well as the status of cosmic ray physics. I comment also briefly on an improvement of the Fermi-LAT limit for cosmogenic neutrinos and on the two neutrino events presented by IceCube first at "Neutrino 2012".

  14. Cosmic microwave background theory

    PubMed Central

    Bond, J. Richard

    1998-01-01

    A long-standing goal of theorists has been to constrain cosmological parameters that define the structure formation theory from cosmic microwave background (CMB) anisotropy experiments and large-scale structure (LSS) observations. The status and future promise of this enterprise is described. Current band-powers in ℓ-space are consistent with a ΔT flat in frequency and broadly follow inflation-based expectations. That the levels are ∼(10−5)2 provides strong support for the gravitational instability theory, while the Far Infrared Absolute Spectrophotometer (FIRAS) constraints on energy injection rule out cosmic explosions as a dominant source of LSS. Band-powers at ℓ ≳ 100 suggest that the universe could not have re-ionized too early. To get the LSS of Cosmic Background Explorer (COBE)-normalized fluctuations right provides encouraging support that the initial fluctuation spectrum was not far off the scale invariant form that inflation models prefer: e.g., for tilted Λ cold dark matter sequences of fixed 13-Gyr age (with the Hubble constant H0 marginalized), ns = 1.17 ± 0.3 for Differential Microwave Radiometer (DMR) only; 1.15 ± 0.08 for DMR plus the SK95 experiment; 1.00 ± 0.04 for DMR plus all smaller angle experiments; 1.00 ± 0.05 when LSS constraints are included as well. The CMB alone currently gives weak constraints on Λ and moderate constraints on Ωtot, but theoretical forecasts of future long duration balloon and satellite experiments are shown which predict percent-level accuracy among a large fraction of the 10+ parameters characterizing the cosmic structure formation theory, at least if it is an inflation variant. PMID:9419321

  15. Hubble Sees a Bizarre Cosmic Rarity

    NASA Image and Video Library

    2013-12-06

    This new Hubble image shows a peculiar galaxy known as NGC 660, located around 45 million light-years away from us. NGC 660 is classified as a "polar ring galaxy," meaning that it has a belt of gas and stars around its center that it ripped from a near neighbor during a clash about one billion years ago.The first polar ring galaxy was observed in 1978 and only around a dozen more have been discovered since then, making them something of a cosmic rarity. Unfortunately, NGC 660’s polar ring cannot be seen in this image, but the image has plenty of other features that make it of interest to astronomers – its central bulge is strangely off-kilter and, perhaps more intriguingly, it is thought to harbor exceptionally large amounts of dark matter. In addition, in late 2012 astronomers observed a massive outburst emanating from NGC 660 that was around ten times as bright as a supernova explosion. This burst was thought to be caused by a massive jet shooting out of the supermassive black hole at the center of the galaxy. Credit: Hubble/NASA/European Space Agency NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  16. 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.

  17. Is cosmic acceleration slowing down?

    SciTech Connect

    Shafieloo, Arman; Sahni, Varun; Starobinsky, Alexei A.

    2009-11-15

    We investigate the course of cosmic expansion in its recent past using the Constitution SN Ia sample, along with baryon acoustic oscillations (BAO) and cosmic microwave background (CMB) data. Allowing the equation of state of dark energy (DE) to vary, we find that a coasting model of the universe (q{sub 0}=0) fits the data about as well as Lambda cold dark matter. This effect, which is most clearly seen using the recently introduced Om diagnostic, corresponds to an increase of Om and q at redshifts z < or approx. 0.3. This suggests that cosmic acceleration may have already peaked andmore » that we are currently witnessing its slowing down. The case for evolving DE strengthens if a subsample of the Constitution set consisting of SNLS+ESSENCE+CfA SN Ia data is analyzed in combination with BAO+CMB data. The effect we observe could correspond to DE decaying into dark matter (or something else)« less

  18. Studying Cosmic Dawn with WFIRST

    NASA Astrophysics Data System (ADS)

    Rhoads, James; Malhotra, Sangeeta; Jansen, Rolf A.; Windhorst, Rogier; Tilvi, Vithal; Finkelstein, Steven; Wold, Isak; Papovich, Casey; Fan, Xiaohui; Mellema, Garrelt; Zackrisson, Erik; Jensen, Hannes; T

    2018-01-01

    Our understanding of Cosmic Dawn can be revolutionized using WFIRST's combination of wide-field, sensitive, high resolution near-infrared imaging and spectroscopy. Guest investigator studies of WFIRST's high latitude imaging survey and supernova search fields will yield orders of magnitude increases in our samples of Lyman break galaxies from z=7 to z>12. The high latitude spectrsocopic survey will enable an unprecedented search for z>7 quasars. Guest observer deep fields can extend these studies to flux levels of Hubble's deepest fields, over regions measured in square degrees. The resulting census of luminous objects in the Cosmic Dawn will provide key insights into the sources of the ultraviolet photons that powered reionization. Moreover, because WFIRST has a wide field (slitless) spectroscopic capability, it can be used to search for Lyman alpha emitting galaxies over the full history of reionization. By comparing the Lyman alpha galaxy statistics to those of continuum sources, we can directly probe the transparency of the intergalactic gas and chart reionization history.Our team is planning for both Guest Investigator and Guest Observer applications of WFIRST to studying Cosmic Dawn, and welcomes dialog with other interested members of the community.

  19. The Cosmic Microwave Background Anisotropy

    NASA Astrophysics Data System (ADS)

    Bennett, C. L.

    1994-12-01

    The properties of the cosmic microwave background radiation provide unique constraints on the history and evolution of the universe. The first detection of anisotropy of the microwave radiation was reported by the COBE Team in 1992, based on the first year of flight data. The latest analyses of the first two years of COBE data are reviewed in this talk, including the amplitude of the microwave anisotropy as a function of angular scale and the statistical nature of the fluctuations. The two-year results are generally consistent with the earlier first year results, but the additional data allow for a better determination of the key cosmological parameters. In this talk the COBE results are compared with other observational anisotropy results and directions for future cosmic microwave anisotropy observations will be discussed. The National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC) is responsible for the design, development, and operation of the Cosmic Background Explorer (COBE). Scientific guidance is provided by the COBE Science Working Group.

  20. Earth Observation

    NASA Image and Video Library

    2013-08-20

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Looking southwest over northern Africa. Libya, Algeria, Niger.

  1. Earth Observation

    NASA Image and Video Library

    2014-09-01

    Earth Observation taken during a night pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: New Zealand Aurora night pass. On crewmember's Flickr page - Look straight down into an aurora.

  2. Earth Observation

    NASA Image and Video Library

    2014-06-07

    ISS040-E-008174 (7 June 2014) --- Layers of Earth's atmosphere, brightly colored as the sun rises, are featured in this image photographed by an Expedition 40 crew member on the International Space Station.

  3. Earth Observation

    NASA Image and Video Library

    2014-06-02

    ISS040-E-006817 (2 June 2014) --- Intersecting the thin line of Earth's atmosphere, International Space Station solar array wings are featured in this image photographed by an Expedition 40 crew member on the International Space Station.

  4. Earth Science

    NASA Image and Video Library

    1992-07-18

    Workers at Launch Complex 17 Pad A, Kennedy Space Center (KSC) encapsulate the Geomagnetic Tail (GEOTAIL) spacecraft (upper) and attached payload Assist Module-D upper stage (lower) in the protective payload fairing. GEOTAIL project was designed to study the effects of Earth's magnetic field. The solar wind draws the Earth's magnetic field into a long tail on the night side of the Earth and stores energy in the stretched field lines of the magnetotail. During active periods, the tail couples with the near-Earth magnetosphere, sometimes releasing energy stored in the tail and activating auroras in the polar ionosphere. GEOTAIL measures the flow of energy and its transformation in the magnetotail and will help clarify the mechanisms that control the imput, transport, storage, release, and conversion of mass, momentum, and energy in the magnetotail.

  5. Discover Earth

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Discover Earth is a NASA-funded project for teachers of grades 5-12 who want to expand their knowledge of the Earth system, and prepare to become master teachers who promote Earth system science in their own schools, counties, and throughout their state. Participants from the following states are invited to apply: Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Washington, DC. Teachers selected for the project participate in a two-week summer workshop conducted at the University of Maryland, College Park; develop classroom-ready materials during the workshop for broad dissemination; conduct a minimum of two peer training activities during the coming school year; and participate in other enrichment/education opportunities as available and desired. Discover Earth is a team effort that utilizes expertise from a range of contributors, and balances science content with hands-on classroom applications.

  6. Earth Observation

    NASA Image and Video Library

    2014-05-31

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: CEO - Arena de Sao Paolo. View used for Twitter message: Cloudy skies over São Paulo Brazil

  7. Earth Observation

    NASA Image and Video Library

    2013-07-26

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Never tire of finding shapes in the clouds! These look very botanical to me. Simply perfect.

  8. Earth Observation

    NASA Image and Video Library

    2014-06-12

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Folder lists this as: Moon, Japan, Kamchatka with a wild cloud. Part of a solar array is also visible.

  9. Earth Science

    NASA Image and Video Library

    1990-10-24

    Solar Vector Magnetograph is used to predict solar flares, and other activities associated with sun spots. This research provides new understanding about weather on the Earth, and solar-related conditions in orbit.

  10. Earth Observation

    NASA Image and Video Library

    2013-08-03

    Earth observation taken during day pass by an Expedition 36 crew member on board the International Space Station (ISS). Per Twitter message: Perhaps a dandelion losing its seeds in the wind? Love clouds!

  11. Earth Observation

    NASA Image and Video Library

    2014-06-27

    Earth Observation taken during a day pass by the Expedition 40 crew aboard the International Space Station (ISS). Part of Space Station Remote Manipulator System (SSRMS) is visible. Folder lists this as: the Middle East, Israel.

  12. Model-independent Constraints on Cosmic Curvature and Opacity

    SciTech Connect

    Wang, Guo-Jian; Li, Zheng-Xiang; Xia, Jun-Qing

    2017-09-20

    In this paper, we propose to estimate the spatial curvature of the universe and the cosmic opacity in a model-independent way with expansion rate measurements, H ( z ), and type Ia supernova (SNe Ia). On the one hand, using a nonparametric smoothing method Gaussian process, we reconstruct a function H ( z ) from opacity-free expansion rate measurements. Then, we integrate the H ( z ) to obtain distance modulus μ {sub H}, which is dependent on the cosmic curvature. On the other hand, distances of SNe Ia can be determined by their photometric observations and thus are opacity-dependent.more » In our analysis, by confronting distance moduli μ {sub H} with those obtained from SNe Ia, we achieve estimations for both the spatial curvature and the cosmic opacity without any assumptions for the cosmological model. Here, it should be noted that light curve fitting parameters, accounting for the distance estimation of SNe Ia, are determined in a global fit together with the cosmic opacity and spatial curvature to get rid of the dependence of these parameters on cosmology. In addition, we also investigate whether the inclusion of different priors for the present expansion rate ( H {sub 0}: global estimation, 67.74 ± 0.46 km s{sup −1} Mpc{sup −1}, and local measurement, 73.24 ± 1.74 km s{sup −1} Mpc{sup −1}) exert influence on the reconstructed H ( z ) and the following estimations of the spatial curvature and cosmic opacity. Results show that, in general, a spatially flat and transparent universe is preferred by the observations. Moreover, it is suggested that priors for H {sub 0} matter a lot. Finally, we find that there is a strong degeneracy between the curvature and the opacity.« less

  13. Experimental cosmic statistics - I. Variance

    NASA Astrophysics Data System (ADS)

    Colombi, Stéphane; Szapudi, István; Jenkins, Adrian; Colberg, Jörg

    2000-04-01

    Counts-in-cells are measured in the τCDM Virgo Hubble Volume simulation. This large N-body experiment has 109 particles in a cubic box of size 2000h-1Mpc. The unprecedented combination of size and resolution allows, for the first time, a realistic numerical analysis of the cosmic errors and cosmic correlations of statistics related to counts-in-cells measurements, such as the probability distribution function PN itself, its factorial moments Fk and the related cumulants ψ and SNs. These statistics are extracted from the whole simulation cube, as well as from 4096 subcubes of size 125h-1Mpc, each representing a virtual random realization of the local universe. The measurements and their scatter over the subvolumes are compared to the theoretical predictions of Colombi, Bouchet & Schaeffer for P0, and of Szapudi & Colombi and Szapudi, Colombi & Bernardeau for the factorial moments and the cumulants. The general behaviour of experimental variance and cross-correlations as functions of scale and order is well described by theoretical predictions, with a few per cent accuracy in the weakly non-linear regime for the cosmic error on factorial moments. On highly non-linear scales, however, all variants of the hierarchical model used by SC and SCB to describe clustering appear to become increasingly approximate, which leads to a slight overestimation of the error, by about a factor of two in the worst case. Because of the needed supplementary perturbative approach, the theory is less accurate for non-linear estimators, such as cumulants, than for factorial moments. The cosmic bias is evaluated as well, and, in agreement with SCB, is found to be insignificant compared with the cosmic variance in all regimes investigated. While higher order statistics were previously evaluated in several simulations, this work presents textbook quality measurements of SNs, 3<=N<=10, in an unprecedented dynamic range of 0.05 <~ ψ <~ 50. In the weakly non-linear regime the results confirm

  14. Galactic cosmic ray composition and energy spectra

    NASA Technical Reports Server (NTRS)

    Mewaldt, R. A.

    1994-01-01

    Galactic cosmic ray nuclei represent a significant risk to long-duration spaceflight outside the magnetosphere. We review briefly existing measurements of the composition and energy spectra of heavy cosmic ray nuclei, pointing out which species and energy ranges are most critical to assessing cosmic ray risks for spaceflight. Key data sets are identified and a table of cosmic ray abundances is presented for elements from H to Ni (Z = 1 to 28). Because of the 22-year nature of the solar modulation cycle, data from the approaching 1998 solar minimum is especially important to reducing uncertainties in the cosmic ray radiation hazard. It is recommended that efforts to model this hazard take advantage of approaches that have been developed to model the astrophysical aspects of cosmic rays.

  15. Earth Observations

    NASA Image and Video Library

    2010-06-16

    ISS024-E-006136 (16 June 2010) --- Polar mesospheric clouds, illuminated by an orbital sunrise, are featured in this image photographed by an Expedition 24 crew member on the International Space Station. Polar mesospheric, or noctilucent (?night shining?), clouds are observed from both Earth?s surface and in orbit by crew members aboard the space station. They are called night-shining clouds as they are usually seen at twilight. Following the setting of the sun below the horizon and darkening of Earth?s surface, these high clouds are still briefly illuminated by sunlight. Occasionally the ISS orbital track becomes nearly parallel to Earth?s day/night terminator for a time, allowing polar mesospheric clouds to be visible to the crew at times other than the usual twilight due to the space station altitude. This unusual photograph shows polar mesospheric clouds illuminated by the rising, rather than setting, sun at center right. Low clouds on the horizon appear yellow and orange, while higher clouds and aerosols are illuminated a brilliant white. Polar mesospheric clouds appear as light blue ribbons extending across the top of the image. These clouds typically occur at high latitudes of both the Northern and Southern Hemispheres, and at fairly high altitudes of 76?85 kilometers (near the boundary between the mesosphere and thermosphere atmospheric layers). The ISS was located over the Greek island of Kos in the Aegean Sea (near the southwestern coastline of Turkey) when the image was taken at approximately midnight local time. The orbital complex was tracking northeastward, nearly parallel to the terminator, making it possible to observe an apparent ?sunrise? located almost due north. A similar unusual alignment of the ISS orbit track, terminator position, and seasonal position of Earth?s orbit around the sun allowed for striking imagery of polar mesospheric clouds over the Southern Hemisphere earlier this year.

  16. Earth Rotation

    NASA Technical Reports Server (NTRS)

    Dickey, Jean O.

    1995-01-01

    The study of the Earth's rotation in space (encompassing Universal Time (UT1), length of day, polar motion, and the phenomena of precession and nutation) addresses the complex nature of Earth orientation changes, the mechanisms of excitation of these changes and their geophysical implications in a broad variety of areas. In the absence of internal sources of energy or interactions with astronomical objects, the Earth would move as a rigid body with its various parts (the crust, mantle, inner and outer cores, atmosphere and oceans) rotating together at a constant fixed rate. In reality, the world is considerably more complicated, as is schematically illustrated. The rotation rate of the Earth's crust is not constant, but exhibits complicated fluctuations in speed amounting to several parts in 10(exp 8) [corresponding to a variation of several milliseconds (ms) in the Length Of the Day (LOD) and about one part in 10(exp 6) in the orientation of the rotation axis relative to the solid Earth's axis of figure (polar motion). These changes occur over a broad spectrum of time scales, ranging from hours to centuries and longer, reflecting the fact that they are produced by a wide variety of geophysical and astronomical processes. Geodetic observations of Earth rotation changes thus provide insights into the geophysical processes illustrated, which are often difficult to obtain by other means. In addition, these measurements are required for engineering purposes. Theoretical studies of Earth rotation variations are based on the application of Euler's dynamical equations to the problem of finding the response of slightly deformable solid Earth to variety of surface and internal stresses.

  17. Cosmic Origins: A Traveling Science Exhibit and Education Program

    NASA Astrophysics Data System (ADS)

    Dusenbery, P. B.; Morrow, C. A.; Harold, J.

    2003-12-01

    The Space Science Institute of Boulder, Colorado, is developing a 3,000 square-foot traveling exhibition, called Cosmic Origins, which will bring origins-related research and discoveries to students and the American public. Cosmic Origins will have three interrelated exhibit areas: Star Formation, Planet Quest, and Search for Life. Exhibit visitors will explore the awesome events surrounding the birth of stars and planets; they will join scientists in the hunt for planets outside our solar system including those that may be in "habitable zones" around other stars; and finally they will be able to learn about the wide range of conditions for life on Earth and how scientists are looking for signs of life beyond Earth. Visitors will also learn about the tools scientists' use, such as space-based and ground-based telescopes, to improve our understanding of the cosmos. Exhibit content will address age-old questions that form the basis of NASA's Origins and Astrobiology programs: Where did we come from? Are we alone? In addition to the exhibit, our project will include workshops for educators and docents at host sites, as well as a public Web site that will use a virtual rendering of exhibit content. The exhibit's size will permit it to visit medium sized museums in underserved regions of the country. It will begin its 3-year tour to 9 host museums and science centers in early 2005. A second 3-year tour is also planned for 2008. The Association of Science-Technology Centers (ASTC) will manage the exhibit's national tour. Current partners in the Cosmic Origins project include ASTC, the Denver Museum of Nature and Science, Lawrence Hall of Science, NASA Astrobiology Institute, NASA missions (e.g. PlanetQuest, SIRTF, and Kepler), New York Hall of Science, the SETI Institute, and the Space Telescope Science Institute. The exhibition is supported by grants from NSF and NASA. This report will focus on the Planet Quest part of the exhibition.

  18. Exposure to galactic cosmic radiation and solar energetic particles.

    PubMed

    O'Sullivan, D

    2007-01-01

    Several investigations of the radiation field at aircraft altitudes have been undertaken during solar cycle 23 which occurred in the period 1993-2003. The radiation field is produced by the passage of galactic cosmic rays and their nuclear reaction products as well as solar energetic particles through the Earth's atmosphere. Galactic cosmic rays reach a maximum intensity when the sun is least active and are at minimum intensity during solar maximum period. During solar maximum an increased number of coronal mass ejections and solar flares produce high energy solar particles which can also penetrate down to aircraft altitudes. It is found that the very complicated field resulting from these processes varies with altitude, latitude and stage of solar cycle. By employing several active and passive detectors, the whole range of radiation types and energies were encompassed. In-flight data was obtained with the co-operation of many airlines and NASA. The EURADOS Aircraft Crew in-flight data base was used for comparison with the predictions of various computer codes. A brief outline of some recent studies of exposure to radiation in Earth orbit will conclude this contribution.

  19. Underground measurements on secondary cosmic rays

    NASA Technical Reports Server (NTRS)

    Wilson, C. W.; Fenton, A. G.; Fenton, K. B.

    1985-01-01

    Measurements made at the Poatina cosmic ray station (41.8 S 149.9 E, 347 m.w.e.) from August 1983 to July 1984 are summarized. The cosmic ray primary particles responsible for events detected at the station have a median primary energy of 1.2 TeV. The motivation for part of this work came from the reported detection of narrow angle anisotropies in the arrival direction of cosmic rays.

  20. Time-dependent evolution of cosmic-ray-modified shock structure: Transition to steady state

    NASA Astrophysics Data System (ADS)

    Donohue, D. J.; Zank, G. P.; Webb, G. M.

    1994-03-01

    Steady state solutions to the two-fluid equations of cosmic-ray-modified shock structure were investigated first by Drury and Volk (1981). Their analysis revealed, among other properties, that there exist regions of upstream parameter space where the equations possess three different downstream solutions for a given upstream state. In this paper we investigate whether or not all these solutions can occur as time-asymptotic states in a physically realistic evolution. To do this, we investigate the time-dependent evolution of the two-fluid cosmic-ray equations in going from a specified initial condition to a steady state. Our results indicate that the time-asymptotic solution is strictly single-valued, and it undergoes a transition from weakly to strongly cosmic-ray-modified at a critical value of the upstream cosmic ray energy density. The expansion of supernova remnant shocks is considered as an example, and it is shown that the strong to weak transition is in fact more likely. The third intermediate solution is shown to influence the time-dependent evolution of the shock, but it is not found to be a stable time-asymptotic state. Timescales for convergence to these states and their implications for the efficiency of shock acceleration are considered. We also investigate the effects of a recently introduced model for the injection of seed particles into the shock accelerated cosmic-ray population. The injection is found to result in a more strongly cosmic-ray-dominated shock, which supports our conclusion that for most classes of intermediate and strong cosmic-ray-modified shocks, the downstream cosmic-ray pressure component is at least as large as the thermal gas pressure, independent of the upstream state. As a result, cosmic rays almost always play a significant role in determining the shock structure and dissipation and they cannot be regarded as test particles.

  1. Time-dependent evolution of cosmic-ray-modified shock structure: Transition to steady state

    NASA Technical Reports Server (NTRS)

    Donohue, D. J.; Zank, G. P.; Webb, G. M.

    1994-01-01

    Steady state solutions to the two-fluid equations of cosmic-ray-modified shock structure were investigated first by Drury and Volk (1981). Their analysis revealed, among other properties, that there exist regions of upstream parameter space where the equations possess three different downstream solutions for a given upstream state. In this paper we investigate whether or not all these solutions can occur as time-asymptotic states in a physically realistic evolution. To do this, we investigate the time-dependent evolution of the two-fluid cosmic-ray equations in going from a specified initial condition to a steady state. Our results indicate that the time-asymptotic solution is strictly single-valued, and it undergoes a transition from weakly to strongly cosmic-ray-modified at a critical value of the upstream cosmic ray energy density. The expansion of supernova remnant shocks is considered as an example, and it is shown that the strong to weak transition is in fact more likely. The third intermediate solution is shown to influence the time-dependent evolution of the shock, but it is not found to be a stable time-asymptotic state. Timescales for convergence to these states and their implications for the efficiency of shock acceleration are considered. We also investigate the effects of a recently introduced model for the injection of seed particles into the shock accelerated cosmic-ray population. The injection is found to result in a more strongly cosmic-ray-dominated shock, which supports our conclusion that for most classes of intermediate and strong cosmic-ray-modified shocks, the downstream cosmic-ray pressure component is at least as large as the thermal gas pressure, independent of the upstream state. As a result, cosmic rays almost always play a significant role in determining the shock structure and dissipation and they cannot be regarded as test particles.

  2. Propagation of cosmic rays in the galaxy

    NASA Technical Reports Server (NTRS)

    Daniel, R. R.; Stephens, S. A.

    1974-01-01

    The characteristics of a model for analyzing the propagation of cosmic rays are discussed. The requirements for analyzing the relevant observational data on cosmic rays are defines as: (1) the chemical and isotopic composition of cosmic rays as a function of energy, (2) the flux and energy spectrum of the individual nucleonic components, (3) the flux and energy spectrum of the electronic component, (4) the cosmic ray prehistory, and (5) the degree of isotropy in their arrival directions as a function of energy. It is stated that the model which has been able to bring to pass the greatest measure of success is the galactic confinement model.

  3. Simulations of ultra-high energy cosmic rays in the local Universe and the origin of cosmic magnetic fields

    NASA Astrophysics Data System (ADS)

    Hackstein, S.; Vazza, F.; Brüggen, M.; Sorce, J. G.; Gottlöber, S.

    2018-04-01

    We simulate the propagation of cosmic rays at ultra-high energies, ≳1018 eV, in models of extragalactic magnetic fields in constrained simulations of the local Universe. We use constrained initial conditions with the cosmological magnetohydrodynamics code ENZO. The resulting models of the distribution of magnetic fields in the local Universe are used in the CRPROPA code to simulate the propagation of ultra-high energy cosmic rays. We investigate the impact of six different magneto-genesis scenarios, both primordial and astrophysical, on the propagation of cosmic rays over cosmological distances. Moreover, we study the influence of different source distributions around the Milky Way. Our study shows that different scenarios of magneto-genesis do not have a large impact on the anisotropy measurements of ultra-high energy cosmic rays. However, at high energies above the Greisen-Zatsepin-Kuzmin (GZK)-limit, there is anisotropy caused by the distribution of nearby sources, independent of the magnetic field model. This provides a chance to identify cosmic ray sources with future full-sky measurements and high number statistics at the highest energies. Finally, we compare our results to the dipole signal measured by the Pierre Auger Observatory. All our source models and magnetic field models could reproduce the observed dipole amplitude with a pure iron injection composition. Our results indicate that the dipole is observed due to clustering of secondary nuclei in direction of nearby sources of heavy nuclei. A light injection composition is disfavoured, since the increase in dipole angular power from 4 to 8 EeV is too slow compared to observation by the Pierre Auger Observatory.

  4. Cosmic ray diffusion: Report of the Workshop in Cosmic Ray Diffusion Theory

    NASA Technical Reports Server (NTRS)

    Birmingham, T. J.; Jones, F. C.

    1975-01-01

    A workshop in cosmic ray diffusion theory was held at Goddard Space Flight Center on May 16-17, 1974. Topics discussed and summarized are: (1) cosmic ray measurements as related to diffusion theory; (2) quasi-linear theory, nonlinear theory, and computer simulation of cosmic ray pitch-angle diffusion; and (3) magnetic field fluctuation measurements as related to diffusion theory.

  5. High Energy Cosmic Electrons: Messengers from Nearby Cosmic Ray Sources or Dark Matter?

    NASA Technical Reports Server (NTRS)

    Moiseev, Alexander

    2011-01-01

    This slide presentation reviews the recent discoveries by the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-Ray Telescope in reference to high energy cosmic electrons, and whether their source is cosmic rays or dark matter. Specific interest is devoted to Cosmic Ray electrons anisotropy,

  6. Cosmic gamma-rays and cosmic nuclei above 1 TeV

    NASA Technical Reports Server (NTRS)

    Watson, A. A.

    1986-01-01

    Work on cosmic gamma rays and cosmic nuclei above I TeV is described and evaluated. The prospect that gamma ray astronomy above I TeV will give new insights into high energy cosmic ray origin within our galaxy is particularly bright.

  7. Contribution from individual nearby sources to the spectrum of high-energy cosmic-ray electrons

    NASA Astrophysics Data System (ADS)

    Sedrati, R.; Attallah, R.

    2014-04-01

    In the last few years, very important data on high-energy cosmic-ray electrons and positrons from high-precision space-born and ground-based experiments have attracted a great deal of interest. These particles represent a unique probe for studying local comic-ray accelerators because they lose energy very rapidly. These energy losses reduce the lifetime so drastically that high-energy cosmic-ray electrons can attain the Earth only from rather local astrophysical sources. This work aims at calculating, by means of Monte Carlo simulation, the contribution from some known nearby astrophysical sources to the cosmic-ray electron/positron spectra at high energy (≥ 10 GeV). The background to the electron energy spectrum from distant sources is determined with the help of the GALPROP code. The obtained numerical results are compared with a set of experimental data.

  8. Detection of Ultrahigh-Energy Cosmic Rays with the Auger Engineering Radio Array

    NASA Astrophysics Data System (ADS)

    Krause, Raphael; Pierre Auger Collaboration

    2017-02-01

    Ultrahigh-energy cosmic rays interact with the Earth's atmosphere and produce great numbers of secondary particles forming an extensive air shower. These air showers emit radiation in the radio frequency range which delivers important information about the processes of radio emission in extensive air showers and properties of the primary cosmic rays, e.g. arrival direction, energy and mass with a duty cycle close to 100%. The radio extension of the world's largest cosmic-ray experiment, the Pierre Auger Observatory, is called the Auger Engineering Radio Array (AERA). In addition to the particle and fluorescence detectors of the Pierre Auger Observatory, AERA investigates the electromagnetic component of extensive air showers using 153 autonomous radio stations on an area of 17km2 .

  9. Exploring Ultra-Heavy Cosmic Rays with the Trans-Iron Galactic Element Recorder (TIGER)

    NASA Astrophysics Data System (ADS)

    Link, Jason; Supertiger Collaboration

    2017-01-01

    Elements heavier than iron are primarily synthesized by neutron capture. These elements can be accelerated as cosmic-rays and measuring their abundances at Earth can yield information about galactic cosmic-rays' sources, the acceleration processes and the composition of the universe beyond the boundaries of our solar system. The Trans-Iron Galactic Element Recorder (TIGER) and its larger successor SuperTIGER was designed to measure the abundance of these ultra-heavy cosmic rays between Z=10 and Z=60. These detectors utilize scintillators with a wavelength shifter bar and PMT readout system as well as aerogel and acrylic Cherenkov detectors to identify the charge and energy of a particle and utilize a scintillating fiber hodoscope to provide trajectory information. In this talk I will review the results from this highly successful program, give the status for the next SuperTIGER flight planned for a December 2017 launch from Antarctica, and discuss the future direction of the program.

  10. Observation of the 60Fe Nucleosynthesis-Clock Isotope in Galactic Cosmic Rays

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Israel, M. H.; Christian, E. R.; Cummings, A. C.; de Nolfo, G. A.; Lave, K. A.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C.; von Rosenvinge, T. T.

    2016-01-01

    Iron-60 (60Fe) is a radioactive isotope in cosmic rays that serves as a clock to infer an upper limit on the time between nucleosynthesis and acceleration. We have used the ACE-CRIS instrument to collect 3.55 105 iron nuclei, with energies 195 to 500 megaelectron volts per nucleon, of which we identify 15 60Fe nuclei. The 60Fe56Fe source ratio is (7.5 2.9) 105. The detection of supernova-produced 60Fe in cosmic rays implies that the time required for acceleration and transport to Earth does not greatly exceed the 60Fe half-life of 2.6 million years and that the 60Fe source distance does not greatly exceed the distance cosmic rays can diffuse over this time, 1 kiloparsec. A natural place for 60Fe origin is in nearby clusters of massive stars.

  11. Earth: Earth Science and Health

    NASA Technical Reports Server (NTRS)

    Maynard, Nancy G.

    2001-01-01

    A major new NASA initiative on environmental change and health has been established to promote the application of Earth science remote sensing data, information, observations, and technologies to issues of human health. NASA's Earth Sciences suite of Earth observing instruments are now providing improved observations science, data, and advanced technologies about the Earth's land, atmosphere, and oceans. These new space-based resources are being combined with other agency and university resources, data integration and fusion technologies, geographic information systems (GIS), and the spectrum of tools available from the public health community, making it possible to better understand how the environment and climate are linked to specific diseases, to improve outbreak prediction, and to minimize disease risk. This presentation is an overview of NASA's tools, capabilities, and research advances in this initiative.

  12. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Panelists discuss how research on early Earth could help guide our search for habitable planets orbiting other stars at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Photo Credit: (NASA/Aubrey Gemignani)

  13. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    Dr. David H. Grinspoon, Senior Scientist, Planetary Science Institute, moderates a panel at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and highlighted how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  14. Ancient Earth, Alien Earths Event

    NASA Image and Video Library

    2014-08-20

    An audience member asks the panelists a question at the “Ancient Earth, Alien Earths” Event at NASA Headquarters in Washington, DC Wednesday, August 20, 2014. The event was sponsored by NASA, the National Science Foundation (NSF), and the Smithsonian Institution and was moderated by Dr. David H. Grinspoon, Senior Scientist at the Planetary Science Institute. Six scientists discussed how research on early Earth could help guide our search for habitable planets orbiting other stars. Photo Credit: (NASA/Aubrey Gemignani)

  15. Cosmic Spider is Good Mother

    NASA Astrophysics Data System (ADS)

    2006-04-01

    Hanging above the Large Magellanic Cloud (LMC) - one of our closest galaxies - in what some describe as a frightening sight, the Tarantula nebula is worth looking at in detail. Also designated 30 Doradus or NGC 2070, the nebula owes its name to the arrangement of its brightest patches of nebulosity that somewhat resemble the legs of a spider. This name, of the biggest spiders on Earth, is also very fitting in view of the gigantic proportions of the celestial nebula - it measures nearly 1,000 light years across! ESO PR Photo 11/06 ESO PR Photo 13b/06 Tarantula's Central Cluster, R136 The Tarantula nebula is the largest emission nebula in the sky and also one of the largest known star-forming regions in all the Milky Way's neighbouring galaxies. Located about 170,000 light-years away, in the southern constellation Dorado (The Swordfish), it can be seen with the unaided eye. As shown in this image obtained with the FORS1 multi-mode instrument on ESO's Very Large Telescope, its structure is fascinatingly complex, with a large number of bright arcs and apparently dark areas in between. Inside the giant emission nebula lies a cluster of young, massive and hot stars, denoted R 136, whose intense radiation and strong winds make the nebula glow, shaping it into the form of a giant arachnid. The cluster is about 2 to 3 million years old, that is, almost from 'yesterday' in the 13.7 billion year history of the Universe. Several of the brighter members in the immediate surroundings of the dense cluster are among the most massive stars known, with masses well above 50 times the mass of our Sun. The cluster itself contains more than 200 massive stars. ESO PR Photo 11/06 ESO PR Photo 13c/06 The Stellar Cluster Hodge 301 In the upper right of the image, another cluster of bright, massive stars is seen. Known to astronomers as Hodge 301, it is about 20 million years old, or about 10 times older than R136. The more massive stars of Hodge 301 have therefore already exploded as

  16. Studying Stratospheric Temperature Variation with Cosmic Ray Measurements

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaohang; He, Xiaochun

    2015-04-01

    The long term stratospheric cooling in recent decades is believed to be equally important as surface warming as evidence of influences of human activities on the climate system. Un- fortunatly, there are some discrepancies among different measurements of stratospheric tem- peratures, which could be partially caused by the limitations of the measurement techniques. It has been known for decades that cosmic ray muon flux is sensitive to stratospheric temperature change. Dorman proposed that this effect could be used to probe the tempera- ture variations in the stratophere. In this talk, a method for reconstructing stratospheric temperature will be discussed. We verify this method by comparing the stratospheric tem- perature measured by radiosonde with the ones derived from cosmic ray measurement at multiple locations around the globe.

  17. Light, Wind and Fire - Beautiful Image of a Cosmic Sculpture

    NASA Astrophysics Data System (ADS)

    2010-02-01

    000 light-years away from Earth and in close proximity to our home, the much larger Milky Way Galaxy. Like its sister the Large Magellanic Cloud, the Small Magellanic Cloud is visible with the unaided eye from the southern hemisphere and has served as an extragalactic laboratory for astronomers studying the dynamics of star formation. This particular image was obtained using the Wide Field Imager (WFI) instrument at the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. Images like this help astronomers chronicle star birth and evolution, while offering glimpses of how stellar development influences the appearance of the cosmic environment over time. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory, and VISTA the largest survey telescope. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".

  18. About cosmic gamma ray lines

    NASA Astrophysics Data System (ADS)

    Diehl, Roland

    2017-06-01

    Gamma ray lines from cosmic sources convey the action of nuclear reactions in cosmic sites and their impacts on astrophysical objects. Gamma rays at characteristic energies result from nuclear transitions following radioactive decays or high-energy collisions with excitation of nuclei. The gamma-ray line from the annihilation of positrons at 511 keV falls into the same energy window, although of different origin. We present here the concepts of cosmic gamma ray spectrometry and the corresponding instruments and missions, followed by a discussion of recent results and the challenges and open issues for the future. Among the lessons learned are the diffuse radioactive afterglow of massive-star nucleosynthesis in 26Al and 60Fe gamma rays, which is now being exploited towards the cycle of matter driven by massive stars and their supernovae; large interstellar cavities and superbubbles have been recognised to be of key importance here. Also, constraints on the complex processes making stars explode as either thermonuclear or core-collapse supernovae are being illuminated by gamma-ray lines, in this case from shortlived radioactivities from 56Ni and 44Ti decays. In particular, the three-dimensionality and asphericities that have recently been recognised as important are enlightened in different ways through such gamma-ray line spectroscopy. Finally, the distribution of positron annihilation gamma ray emission with its puzzling bulge-dominated intensity disctribution is measured through spatially-resolved spectra, which indicate that annihilation conditions may differ in different parts of our Galaxy. But it is now understood that a variety of sources may feed positrons into the interstellar medium, and their characteristics largely get lost during slowing down and propagation of positrons before annihilation; a recent microquasar flare was caught as an opportunity to see positrons annihilate at a source.

  19. Evolution of the cosmic web

    NASA Astrophysics Data System (ADS)

    Cautun, Marius; van de Weygaert, Rien; Jones, Bernard J. T.; Frenk, Carlos S.

    2014-07-01

    The cosmic web is the largest scale manifestation of the anisotropic gravitational collapse of matter. It represents the transitional stage between linear and non-linear structures and contains easily accessible information about the early phases of structure formation processes. Here we investigate the characteristics and the time evolution of morphological components. Our analysis involves the application of the NEXUS Multiscale Morphology Filter technique, predominantly its NEXUS+ version, to high resolution and large volume cosmological simulations. We quantify the cosmic web components in terms of their mass and volume content, their density distribution and halo populations. We employ new analysis techniques to determine the spatial extent of filaments and sheets, like their total length and local width. This analysis identifies clusters and filaments as the most prominent components of the web. In contrast, while voids and sheets take most of the volume, they correspond to underdense environments and are devoid of group-sized and more massive haloes. At early times the cosmos is dominated by tenuous filaments and sheets, which, during subsequent evolution, merge together, such that the present-day web is dominated by fewer, but much more massive, structures. The analysis of the mass transport between environments clearly shows how matter flows from voids into walls, and then via filaments into cluster regions, which form the nodes of the cosmic web. We also study the properties of individual filamentary branches, to find long, almost straight, filaments extending to distances larger than 100 h-1 Mpc. These constitute the bridges between massive clusters, which seem to form along approximatively straight lines.

  20. Evolution of cosmic string networks

    NASA Technical Reports Server (NTRS)

    Albrecht, Andreas; Turok, Neil

    1989-01-01

    A discussion of the evolution and observable consequences of a network of cosmic strings is given. A simple model for the evolution of the string network is presented, and related to the statistical mechanics of string networks. The model predicts the long string density throughout the history of the universe from a single parameter, which researchers calculate in radiation era simulations. The statistical mechanics arguments indicate a particular thermal form for the spectrum of loops chopped off the network. Detailed numerical simulations of string networks in expanding backgrounds are performed to test the model. Consequences for large scale structure, the microwave and gravity wave backgrounds, nucleosynthesis and gravitational lensing are calculated.