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61.
月球表面没有磁场的保护,粒子辐射是人类在月球活动的重要风险要素。概述了月球的辐射环境以及辐射来源,并介绍了月球探测的现状,特别提及了近年来几个较为典型的月球辐射探测实例及其探测结果;介绍了我国“嫦娥4号”上搭载的月表中子与辐射剂量探测仪(Lunar Lander Neutron&Dosimetry,LND)的科学目标及其技术指标。LND的科学目标主要包括:载人登月辐射剂量的测量、月球南极艾特肯盆地水含量的测量、艾特肯盆地FeO含量的测量,以及为日球层科学的研究提供依据。  相似文献   
62.
Triple flybys of the Galilean moons of Jupiter can capture a spacecraft into orbit about Jupiter or quickly adjust the Jupiter-centered orbit of an already captured spacecraft. Because Callisto does not participate in the Laplace resonance among Ganymede, Europa, and Io, triple flyby sequences involving gravity-assists of Callisto, Ganymede, and Io occur only aperiodically for limited time windows. An exhaustive search of triple-flyby trajectories over a 16-year period from 2024 to 2040 using “blind” searching would require 8,415,358 Lambert function calls to find only 127,289 possible triple flyby trajectories. Because most of these Lambert function calls would not converge to feasible solutions, it is much more efficient to prune the solution space using a heuristic algorithm and then direct a much smaller number of Lambert function calls to find feasible triple flyby solutions. The novel “Phase Angle Pruning Heuristic” is derived and used to reduce the search space by 99%.  相似文献   
63.
嫦娥工程技术发展路线   总被引:4,自引:2,他引:2       下载免费PDF全文
月球是距离地球最近的天体,以其独特的空间位置、广阔的科学探索前景,成为人类地外天体探测和资源利用的首选目标和持续选择。简要总结世界各主要航天大国的探月发展历程和后续计划,详细介绍了我国探月工程(嫦娥工程)"绕""落""回"三步走的发展思路和技术路线,分析了后续的发展方向,提出了2030年前月球机器人科研站任务设想。  相似文献   
64.
伞状可展开天线是"嫦娥4号"中继星为着陆于月球背面的"嫦娥4号"着陆器和巡视器提供中继通信的关键单机。对伞状可展开天线的设计原理和构造进行了描述,对天线在轨展开、网面成型与保持、超低温环境适应性等技术难点开展了分析。天线在轨展开采用缓释弹簧分布式驱动展开技术,具有布局灵活、轻便、安装体积小、可靠性高的优点,并开展了寿命、热真空环境展开等试验,验证了天线展开技术的正确性;采用双层网结构设计形式实现天线网面成型与保持,优化了张力网节点数量,开展了型面精度测试和型面在轨热变形预示,验证了天线在轨型面精度达到亚毫米级的设计指标,进一步确保了天线在轨性能满足任务要求;天线部组件最低温度达到–250℃的超低温环境验证结果,表明天线经历超低温环境存储后,结构无损坏,性能无下降,满足天线在轨环境适应性的要求,有效地支撑了"嫦娥4号"中继星中继通信任务的顺利执行。  相似文献   
65.
Space law education has an essential role in the space capacity building of a country because of its importance for human resources development in space law. Comparisons between Canada and China, the European Union and China and the United States of America (USA) and China in space law degree education, course, teaching methodology, institute and practice and communication platform are provided in an attempt to review some issues which exist within the Chinese space law educational system and to seek a better choice for China’s space law education reform. Chinese space law education has achieved noticeable progress over the past two decades. However, it is still limited in comparison to its counterparts in Europe and Northern America. The range of the space law degree education programmes and space-law-related courses is comparatively limited. A gap remains between space law education and practice in China. Chinese space law classes are still dominated by the teacher-centred teaching methodology, although several universities have some new teaching practices. The establishment of seven space law-related research institutes plays an increasingly important role in Chinese space law education, space law and policy research and legal advisory services for the Chinese government and non-governmental sectors. However, these institutes still have a long way to go in comparison with their counterparts in Europe and Northern America. While China has established domestic research platforms for space law communication through international cooperation, it does not provide space law practice platforms for space law education. While international space law does not provide a direct legal foundation for space law education in China, Chinese educational laws can lay a profound legal foundation for Chinese space law education. To promote its national expertise and capacity in space law, based on the three-pillar model and the experiences of its counterparts in North America and Europe, China should adopt a systematic and sustainable regime for its space law education.  相似文献   
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