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751.
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
752.
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
753.
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
754.
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
755.
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
756.
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
757.
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
758.
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
759.
H. O. Funsten R. M. Skoug A. A. Guthrie E. A. MacDonald J. R. Baldonado R. W. Harper K. C. Henderson K. H. Kihara J. E. Lake B. A. Larsen A. D. Puckett V. J. Vigil R. H. Friedel M. G. Henderson J. T. Niehof G. D. Reeves M. F. Thomsen J. J. Hanley D. E. George J.-M. Jahn S. Cortinas A. De Los Santos G. Dunn E. Edlund M. Ferris M. Freeman M. Maple C. Nunez T. Taylor W. Toczynski C. Urdiales H. E. Spence J. A. Cravens L. L. Suther J. Chen 《Space Science Reviews》2013,179(1-4):423-484
The HOPE mass spectrometer of the Radiation Belt Storm Probes (RBSP) mission (renamed the Van Allen Probes) is designed to measure the in situ plasma ion and electron fluxes over 4π sr at each RBSP spacecraft within the terrestrial radiation belts. The scientific goal is to understand the underlying physical processes that govern the radiation belt structure and dynamics. Spectral measurements for both ions and electrons are acquired over 1 eV to 50 keV in 36 log-spaced steps at an energy resolution ΔE FWHM/E≈15 %. The dominant ion species (H+, He+, and O+) of the magnetosphere are identified using foil-based time-of-flight (TOF) mass spectrometry with channel electron multiplier (CEM) detectors. Angular measurements are derived using five polar pixels coplanar with the spacecraft spin axis, and up to 16 azimuthal bins are acquired for each polar pixel over time as the spacecraft spins. Ion and electron measurements are acquired on alternate spacecraft spins. HOPE incorporates several new methods to minimize and monitor the background induced by penetrating particles in the harsh environment of the radiation belts. The absolute efficiencies of detection are continuously monitored, enabling precise, quantitative measurements of electron and ion fluxes and ion species abundances throughout the mission. We describe the engineering approaches for plasma measurements in the radiation belts and present summaries of HOPE measurement strategy and performance. 相似文献
760.
We consider the angular motion of an axi-symmetrical satellite equipped with an active magnetic attitude control system. Dynamics of the satellite is studied on the entire control loop, consisting of a bunch of three successively used algorithms. The control cycle includes the stages of nutation damping, spinning up the satellite about its symmetry axis, and reorienting the symmetry axis into a preset direction in the inertial space. The results are confirmed by numerical simulations. 相似文献