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1.
Adelegation led by CASC President Ma Xingrui visited Turkmenistan on August 8. President of Turkmenistan Gurbanguly Berdimuhamedov received the delegation in a warm, friendly atmosphere. President Gurbanguly Berdimuhamedov highly praised the remarkable achievements of China in the past 50 years. He said that exploration  相似文献   

2.
The ChinaSat-10 satellite was delivered to the customer, China Satellite Communicaitons Co. Ltd. on June 28 by CAST. President of CASC, Mr. Ma Xingrui and related leaders of the two parties attended the delivery ceremony. The satellite was launched in June, 2011 onboard a LM-3B launch vehicle from the XSLC. It is a geosynchronous satellite de  相似文献   

3.
This is the Executive Summary of the 182-page report of the Synthesis Group, which was established in May 1990 by US Vice President Dan Quayle and NASA Administrator Richard Truly. The Group's purpose was to assess and synthesize suggestions for how to accomplish the Space Exploration Initiative (SEI) proposed by President George Bush in July 1989; to suggest several significantly different approaches to human exploration of the solar system; and to identify key technologies required for such exploration. The recommendations of the report are expected to form the basis for several years of study by the USA and, potentially, other countries, before a particular strategy for SEI is selected.  相似文献   

4.
Marcia S. Smith   《Space Policy》2011,27(1):20-23
The major features of President Obama’s new US space policy are discussed and particular aspects are compared with those of the previous Bush policy. In many cases there are similarities of substance but the tone of the latest policy is more outward looking and inclusive, with a far greater emphasis on cooperation, both internationally and with the private sector. And while some complain that the policy does not sufficiently emphasize US leadership, a statement by President Obama on the day of its release makes clear that this remains a paramount goal. Serious questions remain, however, about implementation of the new policy, particularly where it requires substantial government funding such as human spaceflight and the restructured weather/environmental satellite programs.  相似文献   

5.
Apollo should not serve as a model for the many programs for lunar and planetary exploration currently making headway: it was a unilateral effort whose generous budget would be inconceivable today. Yet President Kennedy was an advocate of cooperation in major space missions, an attitude that makes perfect sense today, when so many agencies have ambitious exploration plans. The importance of President G.W. Bush's ‘Vision for Space Exploration’, by providing a focus for NASA and others, has been underestimated. It should give us a chance to find out whether a long-term objective of moving humans off the home planet is really feasible—surely the point of exploration.  相似文献   

6.
John M. Logsdon   《Space Policy》2011,27(1):15-19
In 2010 the administration of President Barack Obama proposed a dramatically new approach to future US human spaceflight. That new strategy was immediately controversial. This article traces the origins of the new spaceflight strategy and the continuing political debate with respect to its acceptance.  相似文献   

7.
燃油分配对超燃冲压发动机的性能影响仿真分析   总被引:1,自引:0,他引:1  
针对超燃冲压发动机两级燃油分配对内流道流动过程、燃烧模态、发动机性能及调节特性的影响问题,建立了发动机一维流动分析模型;对马赫数6/当量比1,马赫数6/当量比0.6,马赫数4/当量比1三种工况不同的一级/二级燃烧室燃油分配比例下的流动过程进行了仿真,并获得了不同燃油分配规律下的发动机性能.通过分析表明:超燃冲压发动机的两级燃油分配比例直接影响发动机内流道内的流动参数分布、燃烧模态及发动机比冲等性能参数.对于马赫数6/当量比1工况,当一级燃烧室的燃油分配比例为30%~70%时,可在全流道内组织纯超声速燃烧,最高比冲超过800 s;对于马赫数6/当量比0.6工况,即使将所有的燃油均在一级燃烧室喷入,流道也不会壅塞,该工况下最大比冲超过800s;对于马赫数4/当量比1工况,燃烧室内组织亚声速燃烧,最大比冲为1 031.9 s;为保证亚声速燃烧扰动不传递到燃烧室入口外,一级燃油分配比例不应过高.  相似文献   

8.
Recognizing that, in the wake of major geopolitical changes, technological developments and global recession, the US space programme needed to change, then Vice President Dan Quayle commissioned a review of the USA's space policy which was completed at the very end of 1992. Its findings — in summary form — and recommendations are reprinted here.  相似文献   

9.
This report by Harry Marshall Jr is based on a paper presented to the 27th International Colloquium on the Law of Outer Space of the International Institute of Space Law during the 35th Congress of the International Astronautical Federation, Lausanne, Switzerland, 9 October 1984. It outlines US attitudes and legislation on the commercialization of space, in particular the space programme of President Reagan, LANDSAT commercialization, ELV commercialization and conflicts of space law.  相似文献   

10.
This article examines the effect that private-sector remote sensing activities might have on the international community and on the future of international cooperation in space. It describes in detail The Land Remote Sensing Commercialization Act of 1984, recently passed by the US Congress and signed by President Reagan. The article concludes that it is possible to develop domestic regulations that balance the economic interests of the private sector with the legal and political concerns of the international community.  相似文献   

11.
Nearly six years after the launch of the first International Space Station element, and four years after its initial occupation, the United States and our 6 international partners have made great strides in operating this impressive Earth orbiting research facility. This past year we have done so in the face of the adversity of operating without the benefit of the Space Shuttle. In his January 14, 2004, speech announcing a new vision for America's space program, President Bush affirmed the United States' commitment to completing construction of the International Space Station by 2010. The President also stated that we would focus our future research aboard the Station on the long-term effects of space travel on human biology. This research will help enable human crews to venture through the vast voids of space for months at a time. In addition, ISS affords a unique opportunity to serve as an engineering test bed for hardware and operations critical to the exploration tasks. NASA looks forward to working with our partners on International Space Station research that will help open up new pathways for future exploration and discovery beyond low Earth orbit. This paper provides an overview of the International Space Station Program focusing on a review of the events of the past year, as well as plans for next year and the future.  相似文献   

12.
Waverider     
Duncan Lunan 《Space Policy》1990,6(4):356-358
On 17–19 October 1990 the University of Maryland hosted the 1st International Hypersonic Waverider Symposium. It has been a long wait; and although far more eminent contributors took part, there was also one amateur group. The comeback for the Waverider concept is due in part, at least, to determined advocacy by the amateur group, ASTRA — probably the first case of its kind. Duncan Lunan, President of ASTRA, explains.  相似文献   

13.
As NASA struggles to fund and execute its ambitious Space Station Freedom and Mission to Planet Earth programmes, President Bush has pledge the nation to a programme to return humans to the Moon to stay and to explore Mars. While not predicted on scientific grounds, this Space Exploration Initiative welcomes the support and participation of the scientific community. Success in establishing this relationship will depend on how the initiative is structured, sold and managed within the context of scientists' past experience with large, manned flight programmes.  相似文献   

14.
The Philippine Space Law was approved by the Philippine Senate and the House of Representatives on June 4, 2019, and was signed by the Philippine President Rodrigo Duterte on August 8, 2019 ~([1]). The approval of this act can be of great significance in the development of Philippine's outer space activities and astronautic industry. This article intends to discuss and analyze the Philippine Space Law background, main content, and its enlightenment with regard to the improvement of China's space law system.  相似文献   

15.
Abstract The Cuatro Ciénegas Basin (CCB) has been identified as a center of endemism for many life-forms. Nearly half the bacterial species found in the spring systems have their closest relatives in the ocean. This raises the question of whether the high diversity observed today is the product of an adaptive radiation similar to that of the Galapagos Islands or whether the bacterial groups are "survivors" of an ancient sea, which would be of interest for astrobiology. To help answer this question, we focused on Firmicutes from Cuatro Ciénegas (mainly Bacillus and Exiguobacterium). We reconstructed the phylogenetic relationships of Firmicutes with 28 housekeeping genes and dated the resulting tree using geological events as calibration points. Our results show that marine Bacillus diverged from other Bacillus strains 838?Ma, while Bacillus from Cuatro Ciénegas have divergence dates that range from 770 to 202?Ma. The members of Exiguobacterium from the CCB conform to a much younger group that diverged from the Andes strain 60?Ma and from the one in Yellowstone 183?Ma. Therefore, the diversity of Firmicutes in Cuatro Ciénegas is not the product of a recent radiation but the product of the isolation of lineages from an ancient ocean. Hence, Cuatro Ciénegas is not a Galapagos Archipelago for bacteria but is more like an astrobiological "time machine" in which bacterial lineages survived in an oligotrophic environment that may be very similar to that of the Precambrian. Key Words: Firmicutes-Cuatro Ciénegas-Precambrian-Molecular dating-Western Interior Seaway. Astrobiology 12, 674-684.  相似文献   

16.
Hubbard GS 《Acta Astronautica》2005,57(2-8):649-660
As we move boldly forward into the 21st century, there has rarely been a more exciting time in which to contemplate the future of space exploration. The President of the United States has made a new and ambitious commitment to exploration of the solar system and beyond. Robotic partners will play a vital role in ensuring that the Vision is truly "sustainable and affordable". Relevant science and technology will be discussed with particular emphasis on expertise from NASA Ames Research Center of which the author is Director. The likely evolution of the balance between human explorers and robotic explorers will be addressed.  相似文献   

17.
Despite its scientific successes, NASA has over the past two decades lost its way, spending billions of dollars on transportation systems that have at bottom been failures. President Obama's cancellation of the costly and unwieldy Constellation program provides an opportunity for genuine reform of the agency and the US space program, through harnessing the innovatory and cost-effective power of commercial entrepreneurs. Examples of the kinds of project they might undertake – including solar power satellites, ‘space taxis’ and a space elevator – are discussed.  相似文献   

18.
In 1955 US President Eisenhower made his Open Skies proposal to the USSR, suggesting an exchange of blueprints showing the location of military installations in the two countries. The proposal was rejected at the time, but today the proliferation of remote sensing technology, along with interrelated security concerns, suggests that the time has come to rethink and update the concept. In this paper the author explains his recent proposal to the US Congress that a national commission be established to explore how information gathered by civilian remote sensing satellites could increase international security and stability without jeopardizing national defence.  相似文献   

19.
This article looks at the collaboration between the USA and Europe to develop a permanently manned space station. The US view was initially somewhat conjectural and European involvement has become a matter of dispute. The problem started with President Reagan's vague invitation which has not been followed up. NASA, directed by Congress, has already established a programme to which European contributions would appear as afterthoughts. While, on the other hand, the Europeans have asked for a collaboration, at the same time insisting on separate ownership, jurisdiction, use and control of the elements they intend to provide.  相似文献   

20.
利用时间步进方法(MOT)求解脉冲电场照射下细线的电流响应分布,分析其后期稳定性。提出一种新的电流系数平均法,不仅可以改善前面时间步的电流值,而且能对当前时间步的电流值进行判断,并采取措施预防振荡,有效消除迭代计算的累积误差,改善后期不稳定性问题。数值仿真表明,新方法消除了引起后期振荡的高频分量,获得了稳定的电流响应分布。  相似文献   

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