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211.
In Italy, the selection of the Italian payload scientists has been performed according to the Spacelab Program of ESA. Twenty-four subjects underwent a screening performed by the Health Service of Italian Air Force. They were requested to pass an exercise test on treadmill and another ten-minute test on centrifuge, subject to the effect of +3 Gz. The authors briefly describe the results of the test. Noteworthy is the determination of Central Flicker Fusion Frequency. This parameter makes it possible to assess the endurance level of the subject, much earlier than other techniques (e.g. EKG). The importance of an accurate preliminary screening is emphasized as well as of successive training periods. Future studies will be undertaken to compare evoked cortical potentials with behaviour parameters of space safety, with a view to setting up a subtle tool of evaluation for both future candidates and payload scientists. 相似文献
212.
Joseph F. Dolan 《Space Science Reviews》1970,10(6):830-868
The variability of the X-ray spectrum of the discrete source Cyg XR-1 (α = 19h 56m δ = +35°.1) is reviewed. The variations observed in the energy region accessible to balloon borne detectors (energies greater
than 20 keV) can be explained by assuming them to be caused by the eclipsing properties of a binary system. It is suggested
that the system is composed of a source of small angular extent having a spectrum similar to that of a black body at approximately
1.5 × 108 K (kT= 12.5 keV) and a non X-radiating companion which eclipses it at intervals of 2.9850 days. The system would be surrounded
by an X-radiating plasma whose photon flux between 1 and 100 keV can be approximated by a power law spectrum whose exponent
is — 1.7. 相似文献
213.
The imaging capabilities of the Exosat and Einstein satellites at soft X-ray wavelengths have begun to show that suitable Galactic X-ray sources have extended ( 10 arcmin) haloes due to scattering of soft X-rays by interstellar dust. A simple argument suggests that similar haloes, due to scattering by intergalactic dust, should exist around distant (z 1) quasars and detailed analysis confirms this conclusion. A search for such haloes around suitable X-ray quasars could provide valuable, model-independent, constraints on the amount and origin of intergalactic dust. 相似文献
214.
R.Z. Sagdeev G.G. Managadze A.A. Martinson Yu.A. Romanovsky R.I. Moisya W.K. Riedler M.F. Friedrich T.G. Adeishvily S.B. Lyakhov L.S. Novikov N.A. Leonov T.I. Gagua I.I. Slyusarenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):129-140
This paper describes two rocket experiments “Aelita” with high power lithium plasma injection. The results of onboard magnetometer, massspectrometer, photometer, plasma, corpuscular and ground radar measurements are given. Dynamics and structure of plasma formation are discussed. 相似文献
215.
John S. Lewis 《Space Science Reviews》1973,14(3-4):401-411
Data on the composition of the satellites of the outer planets and the composition and structure of planetary atmospheres are briefly reviewed in light of simple models for the origin of the solar system and the planets. Some crucial tests of present theories are suggested.Contribution No. 52 of the MIT Planetary Astronomy Laboratory.This is one of the publications by the Science Advisory Group. 相似文献
216.
Ruoff CF 《Aerospace America》1989,27(8):38-41, 46
This article describes the use of robots to perform work in space. In particular, telerobotics, which uses human operators to control the movement and operation of the robots, are explored. The relationship between the human operator and the robot is very complex but these systems are being used to explore planetary surfaces and will also be used in the construction of the space station. Research being conducted at NASA facilities is described, providing a picture of the future of space robotics. 相似文献
217.
Wasson JT 《Astrobiology》2003,3(1):163-179
Large aerial bursts similar to the 1908 Tunguska bolide but much larger in magnitude have surely been responsible for many catastrophic events in the history of the Earth. Because aerial bursts produce shallow (or even negligible) craters, their existence is difficult to document in the geological record. Even aerial bursts as small as Tunguska deposit enough energy to melt approximately 1mm of dry soil. Silica-rich glass formed in such melts has the potential to survive in the soil for many Ma, thus a potential indicator of large aerial bursts is glass that was formed as thick regions within silicate melt sheets. The layered tektites from Southeast Asia and the Libyan desert glass may have formed by a combination of sedimentation and downslope flow of silicate melt heated by radiation from large aerial bursts. The alternative, formation of layered tektites as crater ejecta, cannot account for observations such as uniformly high 10Be contents, the orientation of the magnetic remanence field, and the absence of splash-form (e.g., teardrop or dumbbell) tektites in regions where layered tektites are common. The largest asteroids or comets make craters no matter what their strength. Recent reviews suggest that, for events in the energy range up to 10(19)-10(20) J (about two orders of magnitude larger than the Meteor Crater impact), aerial bursts are more likely than cratering events, and the layered tektites of Southeast Asia imply the existence of aerial bursts one to two orders of magnitude larger still. 相似文献
218.
Induced abnormality in Mir- and Earth grown Super Dwarf wheat. 总被引:4,自引:0,他引:4
D L Bubenheim J Stieber W F Campbell F B Salisbury M Levinski V Sytchev I Podolsky L Chernova I Pdolsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):229-234
Super-dwarf wheat grown on the Mir space station using the Svet "Greenhouse" exhibited morphological, metabolic and reproductive abnormalities compared with Earth-grown wheat. Of prominent importance were the abnormalities associated with reproductive ontogeny and the total absence of seed formation on Mir. Changes in the apical meristem associated with transition from the vegetative phase to floral initiation and development of the reproductive spike were all typical of 'Super-Dwarf' wheat up to the point of anthesis. Observation of ruptured anthers from the Mir-grown plants revealed what appeared to be normally developed pollen. These pollen gains, however, contained only one nuclei, while normal viable pollen is tri-nucleate. A potentially important difference in the flight experiment, compared with ground reference studies, was the presence of a high level of atmospheric ethylene (1,200 ppb). Ground studies conducted by exposing 'Super-Dwarf' wheat to ethylene just prior to anthesis resulted in manifestation of the same abnormalities observed in the space flight samples. 相似文献
219.
D F Smart M A Shea 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(1):45-50
Estimates of the energetic proton environment for a Mars mission are generally extrapolated from the solar proton observations at 1 AU. We find that solar particle events may be divided into two general classes. Events dominated by a near-sun injection of particles onto interplanetary magnetic field lines leading to the spacecraft position represent the "classical" solar particle event associated with solar activity. This class of event will scale in radial distance by the classical power law extrapolation. The extended-interplanetary-shock source generates a maximum flux as the shock passes the detection location. This class of event typically generates maximum fluence, but in this case, the flux and fluence will not scale in the classical manner with radial distance. 相似文献
220.
This article presents main scientific and practical results obtained in course of scientific and applied research and experiments on Mir space station. Based on Mir experience, processes of research program formation for the Russian Segment of the ISS are briefly described. The major trends of activities planned in the frames of these programs as well as preliminary results of increment research programs implementation in the ISS' first missions are also presented. 相似文献