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701.
Edwards Christopher S. Christensen Philip R. Mehall Greg L. Anwar Saadat Tunaiji Eman Al Badri Khalid Bowles Heather Chase Stillman Farkas Zoltan Fisher Tara Janiczek John Kubik Ian Harris-Laurila Kelly Holmes Andrew Lazbin Igor Madril Edgar McAdam Mark Miner Mark O’Donnell William Ortiz Carlos Pelham Daniel Patel Mehul Powell Kathryn Shamordola Ken Tourville Tom Smith Michael D. Smith Nathan Woodward Rob Weintraub Aaron Reed Heather Pilinski Emily B. 《Space Science Reviews》2021,217(7):1-37
Space Science Reviews - Modern observatories have revealed the ubiquitous presence of magnetohydrodynamic waves in the solar corona. The propagating waves (in contrast to the standing waves) are... 相似文献
702.
The speed and mass dependence of meteor air plasma temperatures is perhaps the most important data needed to understand how small meteoroids chemically change the ambient atmosphere in their path and enrich the ablated meteoric organic matter with oxygen. Such chemistry can play an important role in creating prebiotic compounds. The excitation conditions in various air plasma emissions were measured from high-resolution optical spectra of Leonid storm meteors during NASA's Leonid Multi-Instrument Aircraft Campaign. This was the first time a sufficient number and range of temperature measurements were obtained to search for meteoroid mass and speed dependencies. We found slight increases in temperature with decreasing altitude, but otherwise nearly constant values for meteoroids with speeds between 35 and 72 km/s and masses between 10(-5) g and 1 g. We conclude that faster and more massive meteoroids produce a larger emission volume, but not a higher air plasma temperature. We speculate that the meteoric plasma may be in multiphase equilibrium with the ambient atmosphere, which could mean lower plasma temperatures in a CO(2)-rich early Earth atmosphere. 相似文献
703.
Life support components are evaluated for application to an idealized closed life support system which includes an algal reactor for food production. Weight-based trade studies are reported as "break-even" time for replacing food stores with a regenerative bioreactor. It is concluded that closure of the life support gases (oxygen recovery) depends on the carbon dioxide reduction chemistry and that an algae-based food production can provide an attractive alternative to re-supply for longer duration missions. 相似文献
704.
O Chlebovsky M Praslicka 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(10):257-262
Monopotassium D, L-aspartate and monomagnesium D, L-aspartate, both in the solution of 500 mg in 100 ml of drinking water administered prior to, during and after the outset of prolonged continuous irradiation increased the survival of rats and mice and improved neuromuscular coordination and physical ability of mice. 相似文献
705.
O Monje G W Stutte G D Goins D M Porterfield G E Bingham 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):151-167
The colonization of space will depend on our ability to routinely provide for the metabolic needs (oxygen, water, and food) of a crew with minimal re-supply from Earth. On Earth, these functions are facilitated by the cultivation of plant crops, thus it is important to develop plant-based food production systems to sustain the presence of mankind in space. Farming practices on earth have evolved for thousands of years to meet both the demands of an ever-increasing population and the availability of scarce resources, and now these practices must adapt to accommodate the effects of global warming. Similar challenges are expected when earth-based agricultural practices are adapted for space-based agriculture. A key variable in space is gravity; planets (e.g. Mars, 1/3 g) and moons (e.g. Earth's moon, 1/6 g) differ from spacecraft orbiting the Earth (e.g. Space stations) or orbital transfer vehicles that are subject to microgravity. The movement of heat, water vapor, CO2 and O2 between plant surfaces and their environment is also affected by gravity. In microgravity, these processes may also be affected by reduced mass transport and thicker boundary layers around plant organs caused by the absence of buoyancy dependent convective transport. Future space farmers will have to adapt their practices to accommodate microgravity, high and low extremes in ambient temperatures, reduced atmospheric pressures, atmospheres containing high volatile organic carbon contents, and elevated to super-elevated CO2 concentrations. Farming in space must also be carried out within power-, volume-, and mass-limited life support systems and must share resources with manned crews. Improved lighting and sensor technologies will have to be developed and tested for use in space. These developments should also help make crop production in terrestrial controlled environments (plant growth chambers and greenhouses) more efficient and, therefore, make these alternative agricultural systems more economically feasible food production systems. 相似文献
706.
Yu I. Portnyagin O.F. Klyuev A.A. Shidlovsky A.N. Evdokimov T.W. Buzdigar P.G. Matukhin S.G. Pasynkov K.N. Shamshev V.V. Sokolov N.D. Semkin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1991,11(12):89-92
Institute of Experimental Meteorology initiated investigations of anthropogenic contamination (AC) and its influence on the near-earth environment and orbiting vehicles. These investigations are based on rocket experiments on simulation of the effects of gas-dust fluxes at the rate of 7–8 km/s on vehicle optical elements under real space conditions. The fluxes are generated by rocket-borne explosive generators. 相似文献
707.
V. N. Kuril'chik M. Y. Boudjada H. O. Rucker I. F. Kopaeva S. V. Mironov 《Cosmic Research》2005,43(6):413-422
Results of almost four years of continuous observations of the subauroral nonthermal radio emission (SANE) onboard the Interball-1 satellite are presented. The main features of SANE are described and discussed: the intensity and character of a signal, its appearance in time, beam directivity, propagation distance, and other observed parameters. 相似文献
708.
709.
We report new results obtained from the EXOSAT AO- 1 observation of the intermediate polar V1223 Sgr. The detection of a 12.4 minute period in the medium energy X-ray flux with an associated hardness ratio variation has been previously reported in Osborne et al. (1984a). Further work has revealed: a narrow dip at the phase zero in the folded medium energy light curve; 30% modulation in the low energy X-ray (3000 Lexan) flux; a count rate ratio from 3 filters which allow the presence of a bright low temperature blackbody component (kT = .05 –. 40 KeV); and a phase resolved ME spectrum which must have two or more components when the source is bright. New optical ephemerides show that the X-ray and optical pulses are in phase at an orbital phase of = 0.31.Affiliated to the Astrophysics Division, Space Science Dept., ESA 相似文献
710.
Harry O. Ruppe 《Acta Astronautica》1983,10(8):585-586
This Note attempts to clear up the discussions relating to the interpretation of Tsiolkowskiy's equation vs Irving's solution. 相似文献