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Scientific and policy developments in the field of Near-Earth Objects (NEOs) since the UN NEO conference in 1995 are briefly outlined. Some areas of research and discovery have exhibited considerable progress while others have languished. In particular, facilities in the southern hemisphere for discovery and tracking of NEOs are inadequate. Suggestions are made both at the scientific and technical levels as well as at the policy level to provide coordinated and coherent progress in developing a long-term approach to NEO hazard mitigation. The next step should be the establishment of a panel of international scientific experts on the subject.  相似文献   

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In the absence of a mature body of literature on the origins and evolution of the Canadian space program, recent official publications have arbitrarily chosen 1974, the year that Canada's civilian space policy was ratified in the House of Commons, as the popular date of origin. However, this start date ignores several significant policy documents that influenced Canada's space program development prior to that year. This article examines policy that shaped Canada's space program during the ‘golden age’ of space exploration (1958–1974), and will demonstrate that the true origins of the Canadian space program date back much earlier that the current perception.  相似文献   

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The UK civil space strategy for the years 2008–2012 and beyond was published in February 2008. This paper describes the key features of the strategy and highlights those areas that are new or different from the aims set out in previous strategies. In particular, the strategy lays out a new five-part high-level vision for UK civil space.  相似文献   

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There is a large discrepancy between potential needs for nuclear propulsion and power systems for the human exploration of Mars and the current status of R&D funding, public opinion, and governmental support for these technologies. Mission planners and spacecraft designers, energized by the recent claims of possible discovery of life on Mars and responding to increased public interest in the human exploration of Mars, frequently propose nuclear reactors and radioisotope thermoelectric generators (RTGs) for interplanetary spacecraft propulsion and for power supply on the surface of Mars. These plans and designs typically assume that reactors will be available "on-the-shelf," and do not take the extensive R&D costs required to develop such reactors into consideration. However, it is likely that current U.S. policies, if unchanged, will prohibit the launch of nuclear reactors and large RTGs in response to a perceived risk by the public.  相似文献   

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Europe has at last started to integrate the assets of its broad set of actors into a comprehensive European Space Strategy. But will this first approach be ambitious enough to strengthen Europe as a global actor? In this contribution, the individuals responsible for strategy in the French and German space agencies seek an answer to this question. They do so by reviewing the historical background to European space efforts, and its role in shaping present-day activities; setting forth a vision of how Europe should proceed in space, and measuring current progress in drafting a European space strategy against this vision.  相似文献   

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In recent years Micro Systems Technology (MST) was introduced to manufacture miniaturized components for satellite subsystems, like small sensors, valves, micromotors, antennas and many more. These components can be used to build a new class of satellites weighing considerably less than 10 kg, with the capabilities comparable to present microsatellites. With the possibility of cheap mass production of such nanosatellites new applications become possible. However, the construction of very small satellites is connected with problems concerning launch, orbit control and, deorbiting. Furthermore the reduction of size creates certain limits for power consumption, data rates and optical resolutions which have to be carefully considered.  相似文献   

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A marriage between Russian space technology and US space ambitions was unthinkable only a short time ago, but that potential union is now the talk of the town. With the dizzying pace of changes in US-Russian relationships, what is written here in July 1992 may well have changed by the time this article is published. Nevertheless, a glance at what the Russians are selling, what the USA may want to buy and the major policy issues involved is worth a look. Traditional cooperative ventures remain an important part of US-Russian space relations, but are not the focus of this article.  相似文献   

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