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1.
Outer space, a valuable natural resource, has to be managed in order to improve safety, efficiency and economy of space missions and to protect the space environment for future exploration and use. There are several aspects of the management of outer space, few in a satisfactory state, others receiving little attention from the international community, and still others not yet addressed at all. Some of the tasks following from the above requirements may have to be performed by an international space organization, created, possibly and preferably, within the UN system of organizations.  相似文献   
2.
The space elevator will operate in near-Earth space, under the attraction of the Earth, the Moon and the Sun. It will have to avoid collisions with active satellites, with space debris and with meteoroids, not counting other minor adverse phenomena. The exceedingly long cable cannot be a passive and limp body. It must be an active part of the elevator, withstanding lunisolar and other perturbations threatening its stability. The cable must have sensors and thrusters at appropriate locations along the cable. Sensors would serve for detection of objects on a collision course and thrusters for station-keeping and for initiating evasive manoeuvres. Adaptive control must be used for that purpose. Extensive series of numerical simulations will have to be performed to ascertain that the elevator is stable and that possible oscillations do not interfere with the main function of the elevator.  相似文献   
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In the early years of space flight the United Nations rapidly developed the principles which now govern outer space activities. In contrast, international agencies have during the 1980s proved reluctant to confront the escalating problem of space debris, presumbly for fear of the likely expense of remedial action. The author of this Viewpoint argues that not all the necessary measures need be expensive, and even the most unpalatable would be cost effective in the long run. But concerted action is urgently needed before the problem becomes unmanageable. International discussions must be initiated through the Committee on the peaceful Uses of Outer Space without delay.  相似文献   
5.
Measures for the safety of space activities have to be elaborated by the scientific community. They should include principles for collision avoidance, possibly in the form of traffic separation schemes. A reduction of collision probabilities could be achieved by systematic removal of inactive satellites, by establishing disposal orbital belts and by reduction of space debris. Safety of space activities would be enhanced by the adoption of standards for the quality of technical equipment and for the competence of personnel. Also timely information on satellite movement should be made available.  相似文献   
6.
Meteor Phenomena and Bodies   总被引:12,自引:0,他引:12  
Meteoroids can be observed at collision with the Earth's atmosphere as meteors. Different methods of observing meteors are presented: besides the traditional counts of individual events, exact methods yield also data on the geometry of the atmospheric trajectory; on the dynamics and ablation of the body in the atmosphere; on radiation; on the spectral distribution of radiation; on ionization; on accompanying sounds; and also data on orbits. Theoretical models of meteoroid interaction with the atmosphere are given and applied to observational data. Attention is paid to radar observations; to spectroscopic observations; to experiments with artificial meteors and to different types of meteor sounds. The proposed composition and structure of meteoroids as well as their orbits link them to meteorites, asteroids and comets. Meteor streams can be observed as meteor showers and storms. The rate of influx of meteoroids of different sizes onto Earth is presented and potential hazards discussed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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The MAP/WINE winter 1983/84 is studied using the LF-MF-HF A3 absorption and 5 kHz atmospherics observed in Czechoslovakia and some other data. The “normal” winter anomaly in Central Europe is developed well in this winter (maximum in mid-January) and appears to be “free of geomagnetic contamination”. The stratospheric warming activity and related changes of prevailing zonal wind in the lower thermosphere in February and March 1984 are followed by decreases of absorption of radio waves. It agrees with our results from preceding winters /1/.  相似文献   
9.
The Satellite Altimeter Data has been used for a) Determination of differences between mean ocean levels; b) Testing the accuracy of different geopotential models as regards their internal structure over the oceans.  相似文献   
10.
The design presented in this paper is in response to the revolution in private space activities, the increasing public interest in commercial flights to space and the utilization of structures such as space hotels or private orbital habitats. The baseline for the Omicron design concept is the Russian Salyut derived space station module. Salyut was the first space station to orbit the Earth. Its unique design and technical features were what made the development of space stations Salyut 1–7, MIR and the International Space Station (ISS) Zwezda service module possible. Due to its versatility and the reliable operating launch vehicle Proton, this space module series has the potential to be adapted for space hotel development. This paper proposes a conceptual design of the space habitat called Omicron, with particular focus on interior design for the microgravity environment. The Omicron concepts address the needs of space tourism with a strong emphasis on the safety and comfort of the spaceflight participants. The Omicron habitat supports three inhabitants in nominal conditions (e.g., two passengers and one astronaut). The habitat provides a flexible interior, facilities and spaces dynamically transforming in order to accommodate various types of activities, which will be performed in an organically formed interior supporting spatial orientation and movement in microgravity. The future development potential of Omicron is also considered. The baseline version is composed solely of one rigid module with an inverted cupola for observations. An alternative version offers more space using an inflatable structure. Finally, a combination of multiple Omicron modules enables the creation of a larger orbital habitat. The Omicron's subsystems support a few days visit by trained passengers. The transport to the habitat would be provided e.g., by the Soyuz TMA spacecraft carried by the Soyuz launch vehicle in the early stage of Omicron's development, before a fully reusable spacecraft would be available.  相似文献   
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