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Global dependence on the space sector is increasing rapidly. However, the growing challenges outer space poses to international security have not, as yet, been effectively addressed in the United Nations Conference on Disarmament (CD) or in other multilateral fora. This paper briefly reviews the current state of affairs of international security and outer space and explores the challenges the international community faces in building international agreements for improved space security and global stability. It examines some of the hurdles that are faced in tackling space security issues are and provides some thinking on ways to overcome them. The paper concludes that there is a potential role for the disarmament community and the CD in particular. As potential conflicts in outer space emerge, having invested bodies and communities such as the CD and a strong cadre of disarmament diplomats and NGOs to act as an informed hub on space and disarmament issues is essential.  相似文献   

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罗辉 《中国航天》2010,(7):38-39
<正>2010年4月8日,美国总统奥巴马和俄罗斯总统梅德韦杰夫签署了核裁军新条约。新条约将替代已于2009年12月5日到期的《削减和限制进攻性战略武器条约》(START I)。START I签署于1991年7月,1994年12月正式生效,2009年12月5日到期。该条约规定,条约到期后如果没有签署新条约来取代它,可以经双方协商一致,采取延期的方式,允许  相似文献   

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POES Companion is a small satellite that would carry an atmospheric sounding instrument identical to one on a nearby operational polar orbiting spacecraft. The spacing between the two satellites would be controlled and variable. The mission is designed to establish the upper bound on the distance between the two satellites within which data from the instruments are statistically equivalent, and further would demonstrate that two neighboring spacecraft can be managed safely and efficiently. POES Companion will validate new Companion options outlined in this paper that could substantially reduce costs attributable to satellite-based atmospheric sounders for both operational and research programs.  相似文献   

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Earth's subsurface offers one of the best possible sites to search for microbial life and the characteristic lithologies that life leaves behind. The subterrain may be equally valuable for astrobiology. Where surface conditions are particularly hostile, like on Mars, the subsurface may offer the only habitat for extant lifeforms and access to recognizable biosignatures. We have identified numerous unequivocally biogenic macroscopic, microscopic, and chemical/geochemical cave biosignatures. However, to be especially useful for astrobiology, we are looking for suites of characteristics. Ideally, "biosignature suites" should be both macroscopically and microscopically detectable, independently verifiable by nonmorphological means, and as independent as possible of specific details of life chemistries--demanding (and sometimes conflicting) criteria. Working in fragile, legally protected environments, we developed noninvasive and minimal impact techniques for life and biosignature detection/characterization analogous to Planetary Protection Protocols. Our difficult field conditions have shared limitations common to extraterrestrial robotic and human missions. Thus, the cave/subsurface astrobiology model addresses the most important goals from both scientific and operational points of view. We present details of cave biosignature suites involving manganese and iron oxides, calcite, and sulfur minerals. Suites include morphological fossils, mineral-coated filaments, living microbial mats and preserved biofabrics, 13C and 34S values consistent with microbial metabolism, genetic data, unusual elemental abundances and ratios, and crystallographic mineral forms.  相似文献   

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This paper presentes the results of an algorithm developed at INTELSAT to (1) synthesize suboptimal, two-burn midlevel thrust, LEO-GEO transfer trajectories; (2) define practical steering laws to approximate the nominal trajectories; and (3) simulate their performance. Capabilities of the algorithm include: independently selectable constant thrust levels for the two burns, constant acceleration, staging, fixing the mass at either ends of the transfer. Figures of inefficiency versus ideally impulsive transfer are plotted for a reference constant thrust case over a range of initial accelerations. The diagram indicates that acceptable inefficiencies are attainable in the initial acceleration range above 0.1 g. A comparison with an optimal two-burn low-thrust transfer indicates negligible degradation in efficiency. The results of an application to INTELSAT VI are included.  相似文献   

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With recently growing interest in the Active Search for Extraterrestrial Intelligence (SETI), in which humankind would send intentional signals to extraterrestrial civilizations, there have been increased concerns about appropriate policy, as well as the role of space law and ethics in guiding such activities. Implicit in these discussions are notions of responsibility and capability that affect judgments about whether humans or other civilizations should initiate transmissions. Existing protocols that guide SETI research address transmissions from Earth, but there is debate over whether these guidelines should inform de novo transmissions as well. Relevant responsibilities to address include (1) looking out for the interests of humankind as a whole, (2) being truthful in interstellar messages, and (3) benefiting extraterrestrial civilizations. Our capabilities as a species and a civilization affect how well we can fulfill responsibilities, as seen when we consider whether we will be able to reach consensus about message contents (and whether that would be desirable), and whether we have the capacity to decode messages from beings that rely on different sensory modalities. The interplay of these responsibilities and capabilities suggests that humankind should place increased emphasis on Active SETI.  相似文献   

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Abstract

Some of John Bateman's critiques of my article “Qualitative Spatial Reasoning in Interpreting Text and Narrative” are certainly valid. However, the alternative solutions that he proposes do not seem to me to be improvements.  相似文献   

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