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741.
Harry O. Ruppe 《Acta Astronautica》1983,10(7):513-515
For rocket transfers between coplanar circular orbits various areas of flight mechanical interest are outlined, depending upon thrust acceleration. Optimum thrust direction has been assumed. All information presented has been derived from analytical approximations. 相似文献
742.
The dynamics of formation of the ordered structures of charged macroparticles under microgravity conditions is investigated. The experimental observations of the behavior of an ensemble of macroparticles were carried out onboard the Mirspace station. The analysis and comparison of results of experimental and theoretical investigations allow us to conclude that under microgravity conditions the formation of elongated, ordered structures of macroparticles, charged by solar radiation, is possible. 相似文献
743.
V. I. LukyashchenkoS. O. TverdokhlebovN. A. Brukhanov 《Acta Astronautica》1999,44(7-12):525-529
A concept of a universal fitting-out module applicable for space flight test of a solar-powered electric propulsion (EP) as well as for the assembly and deployment of small spacecraft (S/C) from the international space station (ISS) is proposed. 相似文献
744.
N.M. Walters O.G. Malan D.C. Neethling 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(5):105-107
In the course of the South African participation in the Nimbus-7 CZCS project, a fair amount of cloud-free data were collected along the South African West Coast, mainly to study upwelling phenomena. Examples of aerosol radiance maps produced during analysis of these data, including some anomalous results, are discussed. 相似文献
745.
R.C. Butler E. Caroli O. Catani G. Di Cocco E. Morelli A. Rubini G. Spada A. Traci L. Barbareschi A. Igiuni M. Santini G. Villa A. Bazzano C. La Padula F. Polcaro P. Ubertini R.E. Baker J.N. Carter D. Ramsden 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(4):95-98
A large area (6000 cm2) actively shielded low energy gamma-ray telescope is going to be built by an Anglo-Italian collaboration. The telescope, named ZEBRA, will be capable of producing images of the X and gamma ray sky in the energy range 0.015–20 MeV with an intrinsic angular resolution of a few tenths of a degree. A prototype detector has been built in order to experimentally study the main characteristics of the detection plane. The preliminary results obtained during a balloon flight from Trapani, Sicily in July 1981 are presented. 相似文献
746.
J. Nishimura H. Hirosawa O. Ohta H. Akiyama T. Yamagami 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(6):67-70
A relay balloon system for long-duration or large-area observations is described. The system consists of a balloon for scientific observations and a relay balloon for a data-relay terminal between a ground station and the balloon for observation. The system was successfully applied to the observation of electric-power fields (50 and 60 Hz) over the Pacific ocean. The maiximum distance between two balloons was about 1100 km and that between the Sanriku Balloon Center and the main balloon for the observation was about 1300 km. 相似文献
747.
R.A. Harrison A. Fludra E.C. Sawyer J.L. Culhane K. Norman A.I. Poland W.T. Thompson O. Kjeldseth-Moe B. Aschenbach M.C.E. Huber A.H. Gabriel H.E. Mason 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1997,20(12):2239-2248
We present first results from the Coronal Diagnostic Spectrometer (CDS) aboard the ESA/NASA Solar and Heliospheric Observatory (SOHO). CDS is a double spectrometer operating in the 151–785 Å range. This region of the solar spectrum is rich in emission lines from trace elements in the solar atmosphere, which can be used to derive diagnostic information on coronal and transition region plasmas. Early spectra are presented and well identified lines are listed. In addition, examples of images in selected wavelength ranges are shown, for a prominence, a loop system and a bright point, demonstrating well the power of such extreme ultraviolet observations. 相似文献
748.
O. Havnes G.E. Morfill 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(9):85-90
We have calculated the vertical structure of planetary dust rings as it results from a balance between an electrostatic force on the dust grains and the vertical component of the gravitational force from the central planet. The electrostatic force results from the charging of the dust grains by the ambient plasma and a large scale electric field due to a shielding electric field and the resulting vertical dust distribution are strongly dependent on dust size, dust and plasma density, plasma temperature and plasma ion type. The dust density distribution has a different dependence on these parameters in tenuous and in dense dust rings. We solve the relevant equations numerically and also by linearization in the limiting cases of tenuous or dense rings. Our results indicate that the effects treated in this paper may be important in both Jupiter's and Saturn's rings. 相似文献
749.
A.J. Merkys R.S. Laurinavichius O.Y. Rupainene D.V. Shvegzhdene A.V. Yaroshius 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(14):109-116
Gravity may influence different aspects of plant activity. The present report deals with two questions: gravity as an ecological factor determining spatial orientation of plant growth; and second, a possible requirement for gravity in the process of normal growth, morphogenesis and generative development of plants. 相似文献
750.
Maurer RH Roth DR Kinnison JD Goldsten JO Gold RE Fainchtein R 《Acta Astronautica》2003,52(2-6):405-410
We describe the instrument design and detector development for MANES which has been selected to fly on the Mars 2003 Lander. Section 1 explains the need for the spectrometer in determining the increased risk of carcinogenesis for astronauts. Section 2 presents the instrument design including an outline drawing, a cross-sectional view and a detailed block diagram. Sections 3 and 4 describe the low and high energy detector components of the spectrometer and present responses to monoenergetic neutron beams. Sections 5 and 6 explain the design approaches to charged particle discrimination and instrument transfer function modeling. 相似文献