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421.
D. A. Paige M. C. Foote B. T. Greenhagen J. T. Schofield S. Calcutt A. R. Vasavada D. J. Preston F. W. Taylor C. C. Allen K. J. Snook B. M. Jakosky B. C. Murray L. A. Soderblom B. Jau S. Loring J. Bulharowski N. E. Bowles I. R. Thomas M. T. Sullivan C. Avis E. M. De Jong W. Hartford D. J. McCleese 《Space Science Reviews》2010,150(1-4):125-160
The Diviner Lunar Radiometer Experiment on NASA’s Lunar Reconnaissance Orbiter will be the first instrument to systematically map the global thermal state of the Moon and its diurnal and seasonal variability. Diviner will measure reflected solar and emitted infrared radiation in nine spectral channels with wavelengths ranging from 0.3 to 400 microns. The resulting measurements will enable characterization of the lunar thermal environment, mapping surface properties such as thermal inertia, rock abundance and silicate mineralogy, and determination of the locations and temperatures of volatile cold traps in the lunar polar regions. 相似文献
422.
This report is divided into three parts: Section 1 gives a short introduction and a summary of the topics discussed. Section 2 is a position statement by J. Kuhn on the interpretation of the irradiance measurements, while Section 3 gives a position statement by M. Schüssler discussing observations of stars that could be useful for understanding solar variability. 相似文献
423.
G. P. Zank N. V. Pogorelov J. Heerikhuisen H. Washimi V. Florinski S. Borovikov I. Kryukov H. R. Müller 《Space Science Reviews》2009,146(1-4):295-327
The interaction of the solar wind with the local interstellar medium is characterized by the self-consistent coupling of solar wind plasma, both upstream and downstream of the heliospheric termination shock, the interstellar plasma, and the neutral atom component of interstellar and solar wind origin. The complex coupling results in the creation of new plasma components (pickup ions), turbulence, and anomalous cosmic rays, and new populations of neutral atoms and their coupling can lead to energetic neutral atoms that can be detected at 1 AU. In this review, we discuss the interaction and coupling of global sized structures (the heliospheric boundary regions) and kinetic physics (the distributions that are responsible for the creation of energetic neutral atoms) based on models that have been developed by the University of Alabama in Huntsville group. 相似文献
424.
G. Randall Gladstone S. Alan Stern Kurt D. Retherford Ronald K. Black David C. Slater Michael W. Davis Maarten H. Versteeg Kristian B. Persson Joel W. Parker David E. Kaufmann Anthony F. Egan Thomas K. Greathouse Paul D. Feldman Dana Hurley Wayne R. Pryor Amanda R. Hendrix 《Space Science Reviews》2010,150(1-4):161-181
425.
Paul Morgan Matthias Grott Brigitte Knapmeyer-Endrun Matt Golombek Pierre Delage Philippe Lognonné Sylvain Piqueux Ingrid Daubar Naomi Murdoch Constantinos Charalambous William T. Pike Nils Müller Axel Hagermann Matt Siegler Roy Lichtenheldt Nick Teanby Sharon Kedar 《Space Science Reviews》2018,214(6):104
This article discusses relevant physical properties of the regolith at the Mars InSight landing site as understood prior to landing of the spacecraft. InSight will land in the northern lowland plains of Mars, close to the equator, where the regolith is estimated to be \(\geq3\mbox{--}5~\mbox{m}\) thick. These investigations of physical properties have relied on data collected from Mars orbital measurements, previously collected lander and rover data, results of studies of data and samples from Apollo lunar missions, laboratory measurements on regolith simulants, and theoretical studies. The investigations include changes in properties with depth and temperature. Mechanical properties investigated include density, grain-size distribution, cohesion, and angle of internal friction. Thermophysical properties include thermal inertia, surface emissivity and albedo, thermal conductivity and diffusivity, and specific heat. Regolith elastic properties not only include parameters that control seismic wave velocities in the immediate vicinity of the Insight lander but also coupling of the lander and other potential noise sources to the InSight broadband seismometer. The related properties include Poisson’s ratio, P- and S-wave velocities, Young’s modulus, and seismic attenuation. Finally, mass diffusivity was investigated to estimate gas movements in the regolith driven by atmospheric pressure changes. Physical properties presented here are all to some degree speculative. However, they form a basis for interpretation of the early data to be returned from the InSight mission. 相似文献
426.
A. Langmeier M. Sztajno J. Trümper 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(3):121-123
We present the results of a search for millisecond rotational pulsations in the X-ray emission of five low-mass X-ray binaries: MXB1728-34, 4U1702-42, 4U1705-44, 4U1755-33 and GX17+2. The data were obtained by the EXOSAT Medium Energy Experiment Argon Counters (1–20 keV) with a time resolution of 7.8125 milliseconds. We searched for periods in the range from 16 msec to 8 sec. Upper limits of 1.5 – 5% were found at a 3 sigma level. 相似文献
427.
研究了单通道和双通道微波衰减测量系统中的射频泄漏所导致的测量误差。使用电磁屏蔽箱和以铝片包裹连接头的方法降低外部辐射泄漏,在双通道衰减测量系统中使用隔离器以减小内部泄漏。利用高灵敏度锁相放大器测量了射频泄漏信号,通过在60 MHz和5 GHz所得的实测数据比较了单通道和双通道衰减测量系统的射频泄漏误差。实验结果表明射频泄漏得到了有效的抑制。 相似文献
428.
B. Ehmann L. Balázs É. Fülöp R. Hargitai P. Kabai B. Péley T. Pólya A. Vargha J. László 《Acta Astronautica》2011,68(9-10):1560-1566
This paper is about a pilot application of narrative psychological content analysis in the psychological status monitoring of Crew 71 of a space analog simulation environment, the Mars Desert Research Station (MDRS). Both the method and its theoretical framework, Scientific Narrative Psychology, are original developments by Hungarian psychologists [5] (László, 2008). The software was NooJ, a multilingual linguistic development environment [11] (Silberztein, 2008). Three measures were conceptualized and assessed: emotional status, team spirit and subjective physical comfort. The results showed the patterns of these three measures on a daily basis at group level, and allowed for detecting individual differences as well. The method is adaptable to languages involved in space psychology, e.g. Russian, French and German in addition to English. 相似文献
429.
Observations of dust in the solar system and in the diffuse interstellar medium are summarized. New measurements of interstellar dust in the heliosphere extend our knowledge about micron-sized and bigger particles in the local interstellar medium. Interplanetary grains extend from submicron- to meter-sized meteoroids. The main destructive effect in the solar system are mutual collisions which provide an effective source for smaller particles. In the diffuse interstellar medium sputtering is believed to be the dominant destructive effect on submicron-sized grains. However, an effective supply mechanism for these grains is presently unknown. The dominant transport mechanisms in the solar system is the Poynting-Robertson effect which sweeps meteoroids bigger than about one micron in size towards the sun. Smaller particles are driven out of the solar system by radiation pressure and electromagnetic interaction with the interplanetary magnetic field. In the diffuse interstellar medium coupling of charged interstellar grains to large-scale magnetic fields seem to dominate frictional coupling of dust to the interstellar gas. 相似文献
430.
D. Offermann H.G. Brückelmann K.M. Torkar H. Widdel 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(12):123-126
Model mechanisms to explain the D-region winter anomaly have so far not really been successful, considering the many different aspects of this atmospheric/ionospheric phenomenon. A new model is therefore proposed relating the winter anomaly essentially to atmospheric temperature and wind variations. The new mechanism is checked by a set of data obtained during the Western European Winter Anomaly Campaign 1975/76, and additionally by a second set of data taken in earlier years. 相似文献