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Rhea Lüst 《Space Science Reviews》1969,10(2):217-229
The studies carried out in the U.S.A. and in Europe to investigate the possibilities and the scientific merit of a cometary probe are surveyed and reviewed. The scientific objectives of such a mission are given and the conditions are stated which a feasible comet must fulfill. Further, proposals of the different groups for the instrumentation of the probe are discussed.Though not all the groups propose the same comets for a first mission, due to different selection criteria, they agree that a mission to a new, non-periodic comet is out of consideration at present, and that a mission to a periodic comet, though possible in principle, presents various difficulties with respect to orbit accuracy and energy requirements. It is emphasized that a mission to Comet Halley in 1986 would be of special value. 相似文献
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The former Director-General of ESA reviews how Europe got to where it now is in space and highlights the major issues likely to affect it at the moment before discussing the decisions he believes must be made to ensure continuing European succuss in space. 相似文献
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