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901.
E. Marsch E. Antonucci P. Bochsler J. -L. Bougeret B. Fleck R. Harrison Y. Langevin R. Marsden O. Pace R. Schwenn J. -C. Vial 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,29(12):135-2040
The scientific rationale of the Solar Orbiter is to provide, at high spatial (35 km pixel size) and temporal resolution, observations of the solar atmosphere and unexplored inner heliosphere. Novel observations will be made in the almost heliosynchronous segments of the orbits at heliocentric distances near 45 R and out of the ecliptic plane at the highest heliographic latitudes of 30° – 38°. The Solar Orbiter will achieve its wide-ranging aims with a suite of sophisticated instruments through an innovative design of the orbit. The first near-Sun interplanetary measurements together with concurrent remote observations of the Sun will permit us to determine and understand, through correlative studies, the characteristics of the solar wind and energetic particles in close linkage with the plasma and radiation conditions in their source regions on the Sun. Over extended periods the Solar Orbiter will deliver the first images of the polar regions and the side of the Sun invisible from the Earth. 相似文献
902.
A. S. Biryukov I. S. Veselovsky O. R. Grigoryan A. D. Koval'' S. N. Kuznetsov A. P. Kropotkin M. I. Panasyuk S. B. Ryabukha A. A. Us V. A. Shuvalov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(12):135-141
More than 20 years ago V.P. Shabansky suggested that the magnetic system installed aboard the satellite, could be used as a physical instrument for studying the processes which occur in the near Earth space. The corresponding space scales of an artificial “magnetosphere”—“magnisphere”—are 10 m in the experiment with relatively small magnets in the ionosphere and 100 m in the solar wind. The corresponding similarity criteria are estimated. The possible scheme of the experiment with a superconducting magnet (magnetic moment 105 A · m2) installed aboard the satellite is considered. The experimental complex includes a number of systems for measuring the fluxes of charged particles in a wide energy range, DC electric and magnetic fields, the electromagnetic fields in different frequency bands (from X-rays to radio). The scientific objectives are discussed in detail. 相似文献
903.
904.
D. V. Kartashov O. B. Shchuko R. Orosei 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,33(12):2263-2269
The structure of the pulse radar signal reflected from continuously changing layered Martian crust is investigated theoretically. As a simple model of stratigraphy, we considered one layer with electrodynamics’ parameters increasing or decreasing exponentially upon a depth laying on monolith base and covered by homogeneous layer. This exponential changing of electromagnetic properties of the layer is assumed due to exponential changing of porosity (or saturation) in the bedrocks with pores filled by seawater. The conditions of subsurface features resolution are obtained. It is shown that the sign and value for gradient of the electromagnetic properties change can be resolved from the reflection peaks trend. These results are important for subsurface detection of liquid water on Mars by orbit-based radars. 相似文献
905.
Biological dosimetry in Russian and Italian astronauts. 总被引:1,自引:0,他引:1
O Greco M Durante G Gialanella G Grossi M Pugliese P Scampoli G Snigiryova G Obe 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(6):1495-1503
Large uncertainties are associated with estimates of equivalent dose and cancer risk for crews of long-term space missions. Biological dosimetry in astronauts is emerging as a useful technique to compare predictions based on quality factors and risk coefficients with actual measurements of biological damage in-flight. In the present study, chromosomal aberrations were analyzed in one Italian and eight Russian cosmonauts following missions of different duration on the MIR and the international space station (ISS). We used the technique of fluorescence in situ hybridization (FISH) to visualize translocations in chromosomes 1 and 2. In some cases, an increase in chromosome damage was observed after flight, but no correlation could be found between chromosome damage and flight history, in terms of number of flights at the time of sampling, duration in space and extra-vehicular activity. Blood samples from one of the cosmonauts were exposed in vitro to 6 MeV X-rays both before and after the flight. An enhancement in radiosensitivity induced by the spaceflight was observed. 相似文献
906.
Nechaev AP Myasnikov VI Stepanova SI Kozerenko OP Isaev GF Bronnikov SV 《Acta Astronautica》1998,42(1-8):331-338
The methodological approach to the study of cosmonauts errors is discussed in the paper. Within its framework an error is considered in psychophysiological aspect as consequence of cosmonaut "psychophysiological troubles" caused by combined effect of flight extreme conditions on his/her organism. This approach was used for the investigation of interrelation between cosmonauts errors, their psychophysiological state and work-rest schedule peculiarities. It includes procedures of expert analysis of data received in the course of radio and TV sessions with crew, analysis of timelines as well deviations in "crew-spacecraft" system functioning. These data are accumulated, systematized and processed in data base. Realization of the suggested approach does not require specialized onboard equipment and crew members time expenditure. Some results of inflight data analysis are presented to illustrate its potentials. 相似文献
907.
Johannes B Salnitski VP Korsun VG Kaleri AJ Kirsch K Schewtschenko OI Fischer F Dudukin AV Gunga HC 《Acta Astronautica》1998,42(1-8):215-218
A complex psychophysiological test battery (ECG, blood pressure, SCL, finger temperature e.t.c.) was applied on two subjects in space. It could be shown that the subjects react under space conditions differently than on earth. The data received could be classified into four types of regulation. The subjects changed this type of regulation during the flight and returned to their former pattern after the flight. 相似文献
908.
The results of studying a dispersed airflow around a single porous cylinder are presented. The flow field of carrying medium outside the cylinder is described within the framework of the Navier-Stokes equations for incompressible gas; inside the porous cylinder the Darcy-Brinkman extended equations for averaged velocity are used. The numerical solution of the medium equations is achieved in the FLUENT package. In the found field of carrying medium velocities the suspended particle trajectories are calculated. Also given are the dependences of the particle inertial deposition effectiveness on the Stokes number at various values of the Darcy number. 相似文献
909.
T. Miyachi M. Fujii N. Hasebe G. Kuraza K. Mori O. Okudaira N. Yamashita S. Sasaki T. Iwai K. Nogami H. Matsumoto H. Ohashi H. Shibata S. Minami S. Takechi T. Onishi E. Grün R. Srama N. Okada 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(7):1147-1151
The detector characteristics of a pentagonal element were studied by colliding it with hypervelocity micro-particles. A charge-sensitive amplifier was developed for the element of its capacitance ∼10 nF. The output amplitudes were expressed as a linear function of the momentum at collision. Empirical formulas obtained from on-ground experiments could be used for the calibration of the detector. The pentagonal element was potential to measure the momentum during collision from the output amplitude. A set of electrodes on the surface was used to confirm the measurement of the coordinates at collision. A possible application of this pentagonal element on a real-time dust detector was discussed. 相似文献
910.