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661.
J I Gitelson 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(5):167-192
Mars mission like the Lunar base is the first venture to maintain human life beyond earth biosphere. So far, all manned space missions including the longest ones used stocked reserves and can not be considered egress from biosphere. Conventional path proposed by technology for Martian mission LSS is to use physical-chemical approaches proved by the experience of astronautics. But the problem of man living beyond the limits of the earth biosphere can be fundamentally solved by making a closed ecosystem for him. The choice optimum for a Mars mission LSS can be substantiated by comparing the merits and demerits of physical-chemical and biological principles without ruling out possible compromise between them. The work gives comparative analysis of ecological and physical-chemical principles for LSS. Taking into consideration universal significance of ecological problems with artificial LSS as a particular case of their solution, complexity and high cost of large-scale experiments with manned LSS, it would be expedient for these works to have the status of an International Program open to be joined. A program of making artificial biospheres based on preceding experience and analysis of current situation is proposed. 相似文献
662.
George A. Dulk Donald B. Melrose 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(11):185
First recognized by Wu and Lee (Ap. J. 230, 621, 1979), electron-cyclotron masers can be activated under very mild conditions. Large growth rates can occur even for relatively mild anisotropies in the electron velocity distribution, e.g., the one-sided loss cones that commonly occur when electrons with small pitch angles precipitate into high density regions at the footpoints of flaring loops while others are reflected in the converging field in the corona. Maser action can plausibly occur at the second harmonic of the local gyrofrequency and so explain certain very bright (? 1010 K) microwave bursts from the sun and other stars. However, the preponderance of the energy is at the first harmonic.We suggest that masers operating at the local gyrofrequency in a flaring loop generate radiation at decimeter wavelengths that is a significant fraction of the total energy of the flare, in fact (and not coincidentally) comparable with the energy in electrons associated with hard X-ray bursts. Essentially all of the radio energy is trapped in the corona and serves to produce localized heating in a volume large compared with the energy release region. Thus it can transfer energy by radiation from one magnetic loop to another, possibly inducing further instabilities, and spreading the course of the flare. Eventually the energy probably escapes the corona as soft X-rays. The electron-cyclotron maser saturates by extracting the perpendicular energy of the electrons, thereby diffusing them into the loss cone at the maximum possible rate; the enhanced precipitation into the footpoints can produce bright emission in hard X-rays, EUV and Hα and remove any necessity for directive acceleration in the energy release region.Details of the proposed mechanism and effects are contained in two papers by Melrose and Dulk (Ap. J. 259, 1982).This work was sponsored by NASA under grants NAGW-91 and NSG-7287 to the University of Colorado. 相似文献
663.
S. Cazes J. Charra N. Coron B. Cougrand J.-F. Crifo J. Crovisier C. Emerich R. Gispert B. Gondet G. Guyot D. Harduin J.-M. Lamarre G. Levanti C. Maurel D. Parisot F. Rocard P. Salvetat A. Soufflot T. Encrenaz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(9):273-276
The IKS infrared spectro-photometer will fly on board the VEGA platforms. It is designed to characterize the size, temperature and emissivity of the Comet Halley nucleus, to identify the major gaseous components of the inner coma and to detect the emission of the cometary grains. This paper presents the “calibration” experiments required to reduce the raw data: (i) absolute wavelength calibration of the filter wheels; (ii) modeling of the internal signal, as a function of the temperature of the different sub-systems; (iii) absolute and spectral responsivities of each of the spectrometric and photometric channels, as a function of the wavelength and position of the source in the field of view. Finally, we shall indicate the expected S/N ratios. 相似文献
664.
I. Kutiev P. Marinov K.B. Serafimov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(1):119-121
A set of data including over 1400 transition level (TL) encounters of the OGO-6 satellite is used to construct analytical presentations of this altitude upon dip-latitude and longitude. The formula represents the TL variation between ± 50° dip-latitude and 20 h and 04 h local time interval. The data were obtained in the high solar activity period in 1969 and 1970. 相似文献
665.
K.Ya. Kondratyev N.I. Moskalenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(8):53-58
The models of chemical composition and structure of the Earth-type planetary atmospheres are offered. The optical properties of gaseous and disperse phases of the atmospheres are investigated. 相似文献
666.
M. Kalinkov K. Stavrev I. Kuneva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
An attempt is made to compare optical properties of Abell clusters with X-ray sources. 相似文献
667.
E. Costa M. Salvati G. Agnetta R. Di Raffaele G. Gerardi B. Sacco L. Scarsi E. Massaro B. Agrinier J.C. Christi J.L. Masnou A. Bui-Van J.P. Chabaud P. Frabel P. Mandrou J. Narbonne M. Niel G. Rouaix G. Vedrenne 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(4):113-116
We present a large area, balloon borne, NaI(Tl) detector for low-energy gamma rays with temporal signature : FIGARO.The main detector is a mosaic of 12 NaI(Tl) tiles 22.5 × 15 × 5 cm, for a total geometric area of 4050 cm2.In the energy band 140 keV - 6 MeV, the expected background counting rate at float altitude is in the range of two to three thousands counts per second.For pulsar analysis the expected 3δ sensitivity for 5 hours exposition time is 2.5 10?4 ph/cm2.s.MeV (150–500 keV) 1.5 10?4 ph/cm2.s.MeV (1–6 MeV). This performance, together with the large effective area and the relatively short duration of a balloon flight, make FIGARO particularly suitable for the identification of sources by means of temporal analysis.For objectives in the Northern sky, including the Crab pulsar, a transmediterranean flight is planned for the summer of 1982 ; a Southern mission is scheduled in Brazil for the fall of 1983 (Vela, PSR 1822-09). 相似文献
668.
V. Sch nfelder K. Bennett H. Bloemen H. de Boer M. Busetta W. Collmar A. Connors R. Diehl J. W. den Herder W. Hermsen L. Kuiper G. G. Lichti J. Lockwood J. Macri M. McConnell D. Morris R. Much J. Ryan G. Stacy H. Steinle A. Strong B. Swanenburg M. Varendorff C. de Vries C. Winkler 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1993,13(12):647-655
COMPTEL is the first imaging telescope to explore the MeV gamma-ray range (0.7 to 30 MeV). At present, it is performing a complete sky survey. In later phases of the mission selected celestial objects will be studied in more detail. The data from the first year of the mission have demonstrated that COMPTEL performs very well. First sky maps of the inner part of the Galaxy clearly identify the plane as a bright MeV-source (probably due to discrete sources as well as diffuse radiation). The Crab and Vela pulsar lightcurves have been measured with unprecedented accuracy. The quasars 3C273 and 3C279 have been seen for the first time at MeV energies. Both quasars show a break in their energy spectra in the COMPTEL energy range. The 1.8 MeV line from radioactive 26A1 has been detected from the central region of the Galaxy and a first sky map of the inner part of the Galaxy has been obtained in the light of this line. Upper limits to gamma-ray line emission at 847 keV and 1.238 MeV from SN 1991T have been derived. Upper limits to the interstellar gamma-ray emissivity have been determined at MeV-energies. Several cosmic gamma-ray bursts within the field-of-view have been located with an accuracy of about 1°. On 1991 June 9, 11 and 15, COMPTEL observed gamma-ray emission (continuum and line) from three solar flares. Also neutrons were detected from the June 9 and June 15 flares. 相似文献
669.
P.B.M. Stortelder H.L.F. Saeijs 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(8):231-240
In this century large-scale transformations have been carried out in the delta of the Rhine, Meuse and Scheldt in The Netherlands. The following principal consequences are considered: the loss of estuarine ecosystems, the change in the process of sedimentation and erosion, and the development of new aquatic and terrestrial ecosystems. The ecological consequences of the transformation of the Grevelingen estuary into a salt-water lake and some surprising developments are described briefly. The need for a limited restoration of the water exchange between the lake and the North Sea is indicated, as well as the major impacts of the exchange. The necessity for the maintenance or restoration of estuaries, the ecological development and the possibilities of the new lakes, and the management of these lakes by engineering structures are discussed. Careful land-use planning and ecosystem management, backed by research, are needed to make the fullest possible use of the potential offered by new lakes. It is also concluded that salt lakes have interesting perspectives. 相似文献
670.
B. Sylwester J. Sylwester 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(13):239-242
The temperature distribution of the hot plasma emission measure in a large but slowly developing flare has been investigated using the following data obtained from the INTERCOSMOS 4 satellite: (1) the X - ray spectra in the range 1.7 – 1.9 Å, (2) the hard X - ray fluxes in the range 10 – 40 keV. It has been found that all the data can be explained by a consistent thermal model of the emitting region. 相似文献