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991.
992.
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   
993.
In recent years, Bacteria and Archaea have been discovered living in practically every conceivable terrestrial environment, including some previously thought to be too extreme for survival. Exploration of our solar system has revealed a number of extraterrestrial bodies that harbor environments analogous to many of the terrestrial environments in which extremophiles flourish. The recent discovery of more than 105 extrasolar planets suggests that planetary systems are quite common. These three findings have led some to speculate that life is therefore common in the universe, as life as we know it can seemingly survive almost anywhere there is liquid water. It is suggested here that while environments capable of supporting life may be common, this does not in itself support the notion that life is common in the universe. Given that interplanetary transfer of life may be unlikely, the actual origin of life may require specific environmental and geological conditions that may be much less common than the mere existence of liquid water.  相似文献   
994.
This paper reports on two major technology events of great significance in the field of Astronautics which were conceived and developed at the MIT Instrumentation Laboratory during the decade of the fifties. It is a personal memoir by the author on two important topics which should be a part of the written history of our field.Part one details the conception and development by Dr J. Halcombe Laning, Jr of “George”, the world's first algebraic compiler for use on Project Whirlwind—MIT's first experimental all-digital computer. This was indeed challenging since Whirlwind at that time had but 1024 sixteen-bit words. Dr Laning began work in the summer of 1952 and the first version of the George compiler was finished in March of 1953.In the early fifties many people were debating the feasibility of a system for translating algebraic formulae into computer programs which would allow the engineer to avoid the all too painstaking and error-prone task of writing programs using basic computer code. But Hal Laning was the first to do it.In part two of this paper, the author explores the early concepts of energy exchange between a spacecraft and a planet during a close encounter of these two celestial objects. The fact that this energy transfer could be exploited for useful purposes in the development of interplanetary orbits was first documented in an MIT Instrumentation Laboratory report published in April of 1958. The topic has been the subject of recent papers at several IAF congresses, but they failed to recognize the early work at MIT. As a part of this important history, the author describes his own work to develop a round-trip orbit to Mars using the planet Venus for a gravity assist to shorten the flight time from three years to one and a quarter years. The first orbit of this type was obtained by the author on 26 January 1961. To the author's knowledge, no one has even suggested that practical three-dimensional multiple fly-by orbits had been constructed at an earlier date.  相似文献   
995.
H.H. Koelle 《Space Policy》1996,12(2):97-102
The rate of progress in any particular program is primarily dependent on the annual resources committed for the specific program. Soon after the turn of the century, the question of returning to the Moon will probably be raised again among political decision makers. At that time the positive and negative arguments will have to be weighed again. A simple method to analyse the relevant force-field was developed comprising the following steps: (1) Definition of positive and negative forces; (2) cross-impact analysis between the individual forces producing relative weights; (3) probability analysis of the current relevance of the individual forces; (4) estimating resulting negative and positive partial force-fields as functions for selected years between 1960 and 2030; and (5) determination of the strength of the resulting force influencing a decision. An example is presented.  相似文献   
996.
One design for a manned Mars base incorporates a bioregenerative life support system based upon growing higher plants at a low atmospheric pressure in a greenhouse on the Martian surface. To determine the concept's feasibility, the germination and initial growth of wheat (Triticum aestivum) was evaluated at low atmospheric pressures in simulated Martian atmosphere (SMA) and in SMA supplemented with oxygen. Total atmospheric pressures ranged from 10 to 1013 mb. No seeds germinated in pure SMA, regardless of atmospheric pressure. In SMA plus oxygen at 60 mb total pressure, germination and growth occurred but were lower than in the Earth atmosphere controls.  相似文献   
997.
Sandler H 《Acta Astronautica》1995,35(4-5):363-372
The use of artificial gravity in extended space flight is reviewed. Topics examined include synergistic factors, gravity loading, gravity magnitude, uniformity of gravity field, and effects of slow rotation.  相似文献   
998.
Significant progress has been achieved in India in demonstrating the utility of remote sensing data for various oceanographic applications during the last one decade. Among these, techniques have been developed for retrieval of ocean surface waves, winds, wave forecast model, internal waves, sea surface temperature and chlorophyll pigments. Encouraged from these results as well as for meeting the specific and increasing data requirements on an assured basis by oceanographers, India is making concerted efforts for developing and launching state-of-the-art indigenous satellites for ocean applications in the coming years.

The first in the series of ocean satellites planned for launch is Oceansat-1 (IRS-P4) by early 1999. Oceansat-1 carries on-board an Ocean Colour Monitor (OCM) and a Multi-frequency Scanning Microwave Radiometer (MSMR). OCM will have 8 narrow spectral bands operating in visible and near- infrared bands (402–885 nm) with a spatial resolution of 360 m and swath of 1420 km. The MSMR with its all weather capability is configured to have measurements at 4 frequencies viz., 6.6, 10.65, 18 & 21 GHz in dual polarisation mode with a spatial resolution of 120, 80, 40 & 40 km, respectively with an overall swath of 1360 km. The Oceansat-1 with repetitivity of once in two days will provide global data for retrieval of various oceanographic and meteorological parameters such as chlorophyll (primary productivity), sea surface temperature and wind speed, besides a host of other parameters of relevance to meteorology.

A full fledged satellite for ocean applications known as Oceansat-2 (IRS-P7) is also planned for launch during 2002. This satellite with payload mix of microwave (Scatterometer, Altimeter & Passive Microwave Radiometer), Thermal (TIR) and Optical (OCM) sensors, will provide greater in-sight into the global understanding of ocean dynamics/resources. This mission is expected to provide a complete set of oceanographic measurements, which are useful for providing operational oceanographic services.

Efforts are also on towards development of missions having multi-frequency, multipolarisation and multi-look angle microwave payloads including Synthetic Aperture Radar (SAR) and advanced millimeter wave sounders, besides development of imaging spectrometers by 2005.

A well-knit plan has been initiated in India for utilisation of planned Oceansat data. Important efforts initiated in this direction include SATellite Coastal and Oceanographic Research and Ocean Information Services, which are being carried out on an integrated basis aiming at providing services to the down stream users. The paper highlights these efforts in India towards providing an operational ocean information services in the coming years.  相似文献   

999.
The design of the Lunar Exploration Neutron Detector (LEND) experiment is presented, which was optimized to address several of the primary measurement requirements of NASA’s Lunar Reconnaissance Orbiter (LRO): high spatial resolution hydrogen mapping of the Moon’s upper-most surface, identification of putative deposits of appreciable near-surface water ice in the Moon’s polar cold traps, and characterization of the human-relevant space radiation environment in lunar orbit. A comprehensive program of LEND instrument physical calibrations is discussed and the baseline scenario of LEND observations from the primary LRO lunar orbit is presented. LEND data products will be useful for determining the next stages of the emerging global lunar exploration program, and they will facilitate the study of the physics of hydrogen implantation and diffusion in the regolith, test the presence of water ice deposits in lunar cold polar traps, and investigate the role of neutrons within the radiation environment of the shallow lunar surface.  相似文献   
1000.
A new resonant quasi-optic interferometer has been developed which has a unique capability to deduce spatial information about perturbing plasma media. The fundamental property of the resonator is that it is multiply degenerate. Its geometry consists of four spherical mirrors arranged in a confocal ring configuration such that the transverse modes are simultaneously resonant. Energy is coupled into and out of the resonator by thin dielectric film beam splitters. When perturbed, it is found that the resonant frequency of the system depends on the point at which the field is measured and this dependence is directly related to the geometry of the perturbation. The results of a theoretical analysis of the perturbation of the resonator are presented and preliminary experimental measurements of a 4-mm system are discussed.  相似文献   
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