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901.
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
902.
S. N. Walker M. A. Balikhin M. Dunlop 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,30(12):2745-2750
Mirror mode oscillations are often observed in the magnetosheath. According to linear, kinetic theory, these waves do not propagate in the plasma rest frame and posses a linear polarisation. However, observations of these waves show them to exhibit a non-planar polarisation. Using data collected by the AMPTE-UKS satellite on 21st September, 1984, this paper investigates the nature of these waves using the variance analysis technique to determine the polarisation and maximum/minimum variance directions. The results show that the individual oscillations do indeed posses non-planar characteristics and the variation in the maximum/minimum variance directions indicates that these oscillations are in fact 3D structures propagating with the plasma rather than a 2D plane wave. 相似文献
903.
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
904.
J.N. de Villiers 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(6):71-75
Low speed data from high altitude scientific balloon flights can be retrieved by geostationary satellites through existing data collection platform systems. Higher speed data of the order of 1 kbit/s create a more difficult problem, particularly if a response is to be made to the balloon payload in near real time. Different geostationary satellite methods to achieve these more demanding requirements are reviewed, and the more interesting cases identified for possible future experiments. 相似文献
905.
L. Barbareschi C. La Padula M. Mastropietro F. Perotti G. Villa A. Bazzano L. Boccaccini R. Patriarca V.F. Polcaro P. Ubertini R.C. Butler G. Di Cocco G. Spada J.N. Carter P. Charalambous A.J. Dean J.B. Stephen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(4):91-93
In order to improve the low energy capability (15 ÷ 150 KeV) of the balloon borne “ZEBRA” low energy gamma imaging telescope (150 KeV-20 MeV), a large area, high spectral resolution (5% at 60 KeV), low background detector has been designed and is now under development.It consists of two MultiWire Spectroscopic Proportional Counter (SPC), escape gated, that have a sensitive area of 6000 cm2, and are placed above the large area array of sodiumiodide position sensitive elements. 相似文献
906.
J.N. Carter G. Frye C.J. Hall T.L. Jenkins A. Owen D. Ramsden 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(4):49-52
Recent tests of a γ-ray imaging telescope, which incorporated a coded aperture mask and multi-wire proportional counter system produced good images of a tritium target source which was used to generate the 20 MeV protons at a proton Van de Graaff accelerator. This paper indicates what performance one might expect if a large area drift chamber were used in conjunction with a coded aperture mask. The prospects for achieving significant scientific results if such a system were flown on a variety of space vehicles are discussed. 相似文献
907.
L.E. Link W.B. Krabill R.N. Swift 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(2):309-322
Airborne laser systems have demonstrated enormous potential for topographic and bathymetric mapping. Both profiling and scanning systems have been evaluated for terrain elevation mapping, stream valley cross-section determination, and nearshore bottom profiling. Performance of the laser systems has been impressive and for some applications matches current operational accuracy requirements. Determining the position of individual laser measurements remains a constraint for most applications. Laser technology constrains some terrain and bathymetric applications, particularly for water penetration and frequency of measurements for high-spatial resolution over large areas. 相似文献
908.
V. N. Oraevskii S. N. Kuznetsov V. V. Malyshev V. E. Usachov Yu. D. Tychinskii 《Cosmic Research》2004,42(1):23-31
We study a possibility of observing the eclipses of the Sun by the Moon from satellite orbits. The scientific tasks planned to be solved onboard satellites are considered. The requirements for the observation of eclipses and for the appropriate satellite trajectories are formulated. A technique of the analysis and synthesis of such trajectories is developed, and some results of preliminary ballistic studies are presented. These results confirm the efficiency of observing the eclipses onboard satellites. 相似文献
909.
J.R. Belanger A.N. Rencz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1983,3(2):187-191
The effects of a glacially enriched zone of trace elements on soils and vegetation in the Thetford Mines area of Quebec were investigated using ground information plus digital Multispectral Scanner (MSS) data from airborne and Landsat sensors. The enriched zone was developed during the last glaciation when a southeastward flowing glacier eroded and dispersed an ultrabasic outcrop that had anomalous levels of Ni, Cu, Co, Cr, Mg and Fe.The dispersal train of enriched trace elements was detectable over an area at least 70 × 15 km ‘down-ice’ from the outcrop. In this zone total Ni concentrations in the soil ranged from background levels of 10 ppm to levels in excess of 1800 ppm. The dominant tree species, (balsam fir) and (white spruce) reflect the soil anomaly with higher concentrations of trace elements in their tissue and lower concentrations of chlorophyll.An unsupervised enhancement of Landsat imagery showed that a tonal discontinuity was caused by a vegetation segregation related to the heavy metal enrichment soils. A detailed study based on Landsat MSS data was able to establish regional patterns of chlorophyll production by certain plant species closely related to the ultrabasic dispersal train. Multi-channel airborne MSS data confirmed the Landsat soil-plant patterns. 相似文献
910.
Measurements of Energy of Cosmic-Ray Nuclei by Specific Energy Release at the Hadron Cascade Maximum
A method of measuring the particle energy in the range higher than 1 TeV based on detection of the maximum specific energy release in hadron cascades that develop in dense media is proposed and studied. This method makes it possible to improve the accuracy of energy measurements carried out with partial-absorption ionization calorimeters in the high-altitude studies of energy spectra of high-energy cosmic rays. The attainable accuracies of energy measurements are considered for light, intermediate, and heavy nuclei in iron and lead absorbers. The results of modeling are compared with the data of an experiment onboard the Kosmos-1713 satellite. 相似文献