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931.
We consider the behavior of the proper atmosphere of space objects in interaction with a flow of incident particles and when the orientation of an object changes. An asymmetry in the behavior of a sorption film with respect to an incident flow of atmospheric particles and the flow’s angular characteristics is shown, as well as the film influence on operation of sensors of the spacecraft’s attitude control system. A recommendation concerning usage of heavy gases for technological operations onboard spacecraft is given. 相似文献
932.
When studying microwave emission of active regions on the Sun, an effect of parametric resonance between 5-min velocity oscillations in the solar photosphere and sound oscillations of coronal magnetic loops modulating the microwave emission has been discovered for the first time. The effect shows itself as simultaneous excitation in coronal magnetic loop of oscillations with periods 5, 10, and 3 min, which correspond to the pumping frequency, subharmonic, and the first upper frequency of parametric resonance. The parametric resonance can serve as an effective channel of transporting the energy of photospheric oscillations into the upper layers of the solar atmosphere. This effect opens up the important prospects in understanding the mechanisms of coronal plasma heating. 相似文献
933.
G. A. Zherebtsov V. A. Kovalenko S. I. Molodykh O. A. Rubtsova L. A. Vasil’eva 《Cosmic Research》2008,46(4):358-366
We present the mechanism and the concept of a model of the solar activity impact on thermobaric and climatic characteristics of the troposphere. Both are based on the idea of parametric action. The results of analysis are presented concerning specific features and regularities of changes in temperature regime of the troposphere in the period of variable helio-and geophysical activity, as well as long-term variations of temperature and heat content of the troposphere. The influence of changes in circulation in the atmosphere and ocean on processes in the system atmosphere-ocean-cryosphere is considered: thermohaline circulation of the oceans and energy exchange between the atmosphere and ocean. The revealed regularities find their complete explanation within the context of a model and mechanism of solar activity impact on climatic characteristics of the troposphere that were suggested previously by the authors. 相似文献
934.
S. I. Kozlov N. V. Smirnova T. V. Loseva A. N. Lyakhov I. B. Kosarev 《Cosmic Research》2008,46(6):489-498
A theoretical interpretation is given to the experimental data on the luminescence in the visible spectral region of the disturbed upper atmosphere in the conditions of injection of a high-velocity aluminum plasma jet (the “Fluxus” experiment). Mathematical models of optical effects are presented. It is demonstrated that the results of the calculations and the experimental data agree satisfactorily. The principal physical and chemical processes responsible for the observed luminescence are determined. 相似文献
935.
D. V. Doronin 《Cosmic Research》2008,46(3):244-250
Based on the methods of the theory of optimum control of dynamic systems, as well as the methods of inverse problems of dynamics and the energy principle, a combined method is developed for control of the motion of a flying vehicle of the Aerospace plane type during the long flight in the atmosphere. The disturbed motion is considered under the conditions when there are constraints on the values of control actions and on functions of phase coordinates. 相似文献
936.
The problem connected with formation of lenses and chaotic bands on Europa’s ice surface are considered. Some assumptions concerning their formation due to temperature stresses in the ice cover of Jupiter’s moon and action of gravitational tidal forces are put forward. 相似文献
937.
A. V. Bobylev A. A. Dyad’kin V. I. Kobzev V. M. Poedinok A. G. Reshetin S. N. Suprunenko V. A. Jaroshevskii 《Cosmic Research》2008,46(1):74-89
We consider the problems of control of the angular and trajectory motion of the Kliper re-entry vehicle. This spacecraft with a moderate hypersonic lift-to-drag ratio is designed according to the load-carrying frame scheme. Gas-dynamic engines, a split balancing flap, and an air brake are used as mounting devices of control. 相似文献
938.
Billings L Cameron V Claire M Dick GJ Domagal-Goldman SD Javaux EJ Johnson OJ Laws C Race MS Rask J Rummel JD Schelble RT Vance S 《Astrobiology》2006,6(5):735-813
The Astrobiology Primer has been created as a reference tool for those who are interested in the interdisciplinary field of astrobiology. The field incorporates many diverse research endeavors, but it is our hope that this slim volume will present the reader with all he or she needs to know to become involved and to understand, at least at a fundamental level, the state of the art. Each section includes a brief overview of a topic and a short list of readable and important literature for those interested in deeper knowledge. Because of the great diversity of material, each section was written by a different author with a different expertise. Contributors, authors, and editors are listed at the beginning, along with a list of those chapters and sections for which they were responsible. We are deeply indebted to the NASA Astrobiology Institute (NAI), in particular to Estelle Dodson, David Morrison, Ed Goolish, Krisstina Wilmoth, and Rose Grymes for their continued enthusiasm and support. The Primer came about in large part because of NAI support for graduate student research, collaboration, and inclusion as well as direct funding. We have entitled the Primer version 1 in hope that it will be only the first in a series, whose future volumes will be produced every 3-5 years. This way we can insure that the Primer keeps up with the current state of research. We hope that it will be a great resource for anyone trying to stay abreast of an ever-changing field. 相似文献
939.
Based on simultaneous observations performed by several spacecraft, we evaluate the orientation of sharp (with a duration of a few minutes) and large (tens and hundreds percent of the mean value) fronts of the solar wind plasma (changes in the ion flux and ram pressure). The orientation of the fronts is determined with respect to the Sun–Earth line and to two planes in space for several tens of the largest (in amplitude) changes of the ion flux. A considerable fraction of these fronts (about 50%) has an inclination to the plane perpendicular to the Sun–Earth line that exceeds 30°. 相似文献
940.
O. S. Ougolnikov 《Cosmic Research》2003,41(2):141-146
The paper is devoted to searching for a possible phenomenon of the gravitational lensing of cosmic gamma-ray bursts on celestial bodies of a globular cluster type (mesolensing). If this phenomenon takes place, gamma-ray bursts should have light curves with two or three similar components whose spectra are identical. These components are separated in time by a few seconds. Using a statistical method developed for comparing the components, we have found in the BATSE catalog 11 candidates of gamma-ray bursts with mesolensing for the entire time of operation of the Compton Gamma-Ray Observatory (1991–2000). Two of these 11 gamma-ray bursts have light curves with three components. The possibility of gravitational mesolensing of these gamma-ray bursts on the King's type bodies is investigated. 相似文献