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1.
美国火星表面探测使命述评(上)   总被引:3,自引:1,他引:3  
从1975年发射(1976年着陆火星)的海盗-1探测器以来,美国已成功执行了6次火星表面探测使命,即海盗-1与海盗-2轨道器/着陆器,"火星探路者"(MPF)着陆器/巡游车,"勇气"与"机遇"火星探测巡游车(MER),以及"凤凰"着陆器;而推迟到2011年发射的"好奇心"火星科学实验室(MSL)将火星着陆技术与表面巡游车技术推向一个新的高度。从"海盗"着陆器到"好奇心"巡游车、美国历经三种火星着陆系统与三代火星表面巡游车技术的发展。三种着陆系统为着陆腿着陆系统("海盗"与"凤凰"),气囊着陆系统(MPF与MER),以及空中吊机着陆系统(MSL)。三代巡游车为MPF"旅居者"巡游车、MER"勇气"与"机遇"巡游车,以及MSL"好奇心"巡游车。现在,美国在火星进入、降落与着陆(EDL)运作与表面避障移动方面,已达到技术成熟与先进的水平,满足安全着陆与表面移动探测的要求。文章阐述美国上述七项火星表面探测使命的立项背景、科学目标与有效载荷、飞行系统组成,以及飞行运作程序;分析美国火星着陆技术与表面巡游车技术的发展。  相似文献   

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The paper, ‘Space sustainability through the sustainable management of common-pool resources: a framework and potential policies’ by Brian Weeden and Tiffany Chow, researches Long-Term Sustainability issues (LTS) from the perspectives of both economics and governance, focusing on analyzing Elinor Ostrom's principles, and puts forward the main elements for a management regime. Their paper will be helpful for the international community to understand the importance of LTS, to further discussions in this field and even to shape a framework for tackling LTS. On the other hand, some of the principles raised by Ostrom still need to be clarified and deliberated throughout the international community. This commentary will analyze some of Ostrom's principles from the perspective of the 1967 Outer Space Treaty (OST) and put forward the values LTS should encompass based on an analysis of its relations with provisions in the OST.  相似文献   

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The US space programme continues to face difficulties in restructuring to meet existing political and fiscal conditions, in part because the basic structure and focus of the programme derive from the tensions of the Cold War. This paper argues that the world's new, more complicated political and economic conditions present a challenge for US policy makers that can be met with a renewed focus on the pursuit of science and the public good, within the context of international economic competition and political and scientific cooperation.  相似文献   

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The political climate today is more favourable for joint superpower cooperation in space than it has been for many years. The authors of this Viewpoint, who studied together as members of the inaugural class of the International Space University, trace recent developments in the USA and USSR and evaluate how they might affect cooperation. Ironically, they find, it is the common problems both nations face in relation to space activities - budgetary constraints and declining political support for their space programmes - that argue most forcefully for cooperation. But a subtle and initially modest strategy will be needed to overcome the obstacles that stand in the way.  相似文献   

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The USA adopted a new defence strategy in 2012 which responds to the changing geopolitical landscape and straightened economic circumstances. The emphasis is on leaner, more flexible and diversified operations, while priority areas have shifted from Europe to the Asia-Pacific (in acknowledgement of China's growing military might) and the Middle East. This will have consequences for Europe, which is now expected to take a greater share of the strategic burden. The major developments in the strategy – such as eschewing the pursuit of lengthy engagements on more than one front, and using the military to complement diplomatic and economic initiatives – are discussed. Europe is urged to respond by maintaining its national strategic and industrial autonomy, including in access to space and missile defence.  相似文献   

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Hubert Fabre   《Space Policy》2002,18(4):208-286
With the growth of commercial activities in outer space, insurers have found an emerging new market. Insurance policy for space satellites has been built chiefly in France and the USA and underwent various crises in the 1980s and 1990s. While the main risks have been more or less identified, their occurrence has shifted from the launch phase to the orbital period over the past few years. At the same time, the duration of insurance policies has been extended up to five years in certain cases, with an adverse effect on profits. The dual-use nature of most spacecraft also makes it difficult to obtain data necessary for the precise identification of risk. An analysis of the space insurance market and its contractual regime is presented, with the aim of identifying emerging trends, and the means by which insurers can develop this still immature sector without compromising their profits.  相似文献   

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有关大型空间平台(空间站和航天飞机)在国家空间安全中的应用.尤其是军事应用问题.无论是在国内或是在国外,长期以来一直受到人们的关注。  相似文献   

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美国海军会同美国国防高级研究项目局正在实施一项无人作战机研制计划,预计于2015到2020年服役,主要执行三种任务:监视、打击和压制敌防空系统。 据透露,这种新型无人作战机可以单独使用,也可以与E—2C鹰眼有人驾驶飞机一起使用。如果带上收发分置接收机,它们能够提供较大区域的雷达图像。由于是无人驾驶飞机,它们可以接近前沿阵地而不会像有人驾驶飞机那样,使飞行员有生命危险。无人作战机可完成多种任务,如携带地面跟踪传感器、合成孔径雷达传感器/移动目标指示器等,或者进行现场化学、生物制剂探测。 在执行作战任…  相似文献   

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《中国航天》2000,(4):28
负责中国对外发射服务的长城工业总公司新闻发言人就美国媒体报道美国务院军贸控制办公室指责洛克希德·马丁公司向中国提供火箭技术帮助一事发表谈话称 ,近日来美国媒体以大量篇幅报道美国务院4月 4日致洛马公司的指控信 ,称 1 994年中国在研制卫星近地点固体发动机 EPKM过程中可能得到了洛克希德·马丁公司的技术帮助。长城公司发言人称 ,这种说法是毫无事实根据的 ,也是不负责任的。该发言人称 ,1 993年 3月2日中国长城工业总公司与亚洲卫星公司签订了用中国长二捆火箭向低地球轨道发射洛克希德·马丁公司制造的亚洲二号卫星以及采购中…  相似文献   

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提高在空间的作战能力是美国军事转型的目标之一。近年来,虽然一些国家努力防止空间的武器化,但美国的空间武器技术一直在研究和发展。  相似文献   

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The initiation of a new vision for exploration, as articulated by US President George W. Bush on 14 January 2004, has excited much interest. This article analyzes the dynamics and potential for changes in the processes and participants in future space policy and space exploration activities. It examines a range of possible alternative paths for NASA and the US government's space exploration activities, the international space community and the private sector in the articulation and pursuit of future space exploration endeavors. It concludes that the new vision for exploration brings about both an opportunity and indeed a necessity for movement towards new and innovative methods and institutions for the effective conduct of multidimensional and multilateral space exploration activities in the future.  相似文献   

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The attitude motion of an artificial satellite carrying a strong magnet is studied. The approximate first integrals of the problem, i.e., adiabatic invariants, are indicated. The basic properties of the satellite motions close to the regular precessions with slowly varying parameters are established via the analysis of the adiabatic invariants.  相似文献   

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轨道舱的功用如果用简单的语言来概括的话,一是为航天员提供生活和工作支持,二是作为航天员出舱的气闸舱来使用.中国航天科技集团空间技术研究院总体部的一位设计师这样向记者概括轨道舱的功用.  相似文献   

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This article provides an overview of NASA's plans to encourage commercial use of the International Space Station (ISS). It examines the reasons driving such commercialization and highlights those private companies currently most interested in undertaking profit-making operations on the station, as well as discussing those activities most likely to be seen as commercial possibilities. The steps NASA is taking to stimulate private interest are enumerated. Various unresolved issues are raised, such as the legal issues associated with commercial research, charging policy for in-orbit operations and ‘metering’ of in-orbit resources. It is noted that the international dimension of the ISS has thus far received little consideration in the USA.  相似文献   

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After a proposition from Russia to France, ESA agreed to see Soyuz rockets take off from French Guiana. From industry, to governments and agencies, many Russian and European actors were involved in this project and they all had different motives. It is therefore relevant to try to discern them so as to understand the rationale behind this cooperative endeavor. Soyuz's primary role is to consolidate Arianespace commercial position in the launching market and to bring activity and founding to a stagnating Russian space sector. With this decision Arianespace will have a full range of commercially available launchers with Soyuz completing the two European rockets Vega and Ariane V. But since Vega and Ariane must have the priority, there is a risk to see an insufficient launch rate for Soyuz, which would not satisfy the Russian partners. Commercial elements alone cannot justify the agreement. There is a larger strategic ambition behind. What is at stake is the future development of innovative launch systems. It is important for ESA to maintain an autonomous access to space and to maintain a dynamic and strong European propulsion industry. Cooperation with Russia can offer an increase of expandable rockets capabilities and can pave for the next generation of launch vehicles. Moreover, we can detect an interest in acquiring a system that has the potential for human space flight capacity. Finally, the decision to launch Soyuz from French Guiana was the conjunction of Russian and French national interests, which led to a complete redefinition of the relations between Europe and Russia. It is of strategic importance that we, Europeans, adapt to this evolution and understand the new place that Russia takes in our space sector.  相似文献   

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<正>2010年6月28日,美国总统奥巴马签发新的《国家航天政策》(以下简称新政策),以取代2006年8月出台的《国家航天政策》。与2006年的航天政策相比,新政策调整了具有"单边主义"色彩的相关内容,语气与措辞也相对比较平和。  相似文献   

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