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1.
A concept of a universal fitting-out module applicable for space flight test of a solar-powered electric propulsion (EP) as well as for the assembly and deployment of small spacecraft (S/C) from the international space station (ISS) is proposed. 相似文献
3.
The primary objective of the International Space Station (ISS) is to provide a long-term quiescent environment for the conduct of scientific research for a variety of microgravity science disciplines. This paper reports to the microgravity scientific community the results of an initial characterization of the microgravity environment on the International Space Station for increments 2 through 4. During that period almost 70,000 hours of station operations and scientific experiments were conducted. 720 hours of crew research time were logged aboard the orbiting laboratory and over half a terabyte of acceleration data were recorded and much of that was analyzed. The results discussed in this paper cover both the quasi-steady and vibratory acceleration environment of the station during its first year of scientific operation. For the quasi-steady environment, results are presented and discussed for the following: the space station attitudes Torque Equilibrium Attitude and the X-Axis Perpendicular to the Orbital Plane; station docking attitude maneuvers; Space Shuttle joint operation with the station; cabin de-pressurizations and the station water dumps. For the vibratory environment, results are presented for the following: crew exercise, docking events, and the activation/de-activation of both station life support system hardware and experiment hardware. Finally, a grand summary of all the data collected aboard the station during the 1-year period is presented showing where the overall quasi-steady and vibratory acceleration magnitude levels fall over that period of time using a 95th percentile benchmark. 相似文献
4.
As humanity prepares to extend its reach beyond low-Earth-orbit for the first time since the 1970s, a new symbol of international cooperation is needed to further promote the message of peace and collaboration such exploration entails. The space race that occurred between the USSR and the USA is an ill-suited model for long-term sustained space exploration because it is too costly and too resource-intensive for a single nation to bear. While competition is healthy for technology development, the success of a sustained space exploration strategy lies beyond technological capabilities. It lies in international cooperation, space policy, and public support. Without these, no program can realistically achieve a sustained presence in space beyond low-Earth orbit. To this effect, this paper proposes a cost-effective first step in the form of a universal symbol which, when placed alongside national flags displayed on hardware and astronaut/cosmonaut/taikonaut flight-suits, would send a strong message to the world that space exploration is done for the benefit of humanity as a whole, not just for spacefaring nations. The “Blue Marble”, the first complete picture of Earth taken from space by humans in 1972, fits this universally appealing symbol. This symbol requires no political collaboration between countries, yet is an image that anyone, anywhere in the world, can relate to regardless of nationality, ethnic origin or religious beliefs. Placed on the shoulder pads of human ’nauts – ambassadors of planet Earth – or prominently displayed on spacebound hardware, this symbol would send a universal message to present and future generations that, in space, our planet is working together for the benefit of everyone. 相似文献
5.
This report by Ray Williamson of the US Office of Technology Assessment, looks at the prospects for commercialization of space into the 21st century and discusses the relative benefits of private v government investment. The report is taken from a revised version of an article originally appearing in the October 1982 issue of Futures. A fully updated paper will appear in Michiel Schwarz and Paul Stares (eds), ‘The Exploitation of Space: Policy Trends in the Military and Commercial Uses of Space’ (Butterworths, Guildford, UK, 1985). 相似文献
6.
To understand the chemical behavior of organic molecules in the space environment, amino acids and a dipeptide in pure form and embedded in meteorite powder were exposed in the PROCESS experiment in the EXPOSE-E facility mounted on the European Technology Exposure Facility (EuTEF) platform on board the International Space Station (ISS). After exposure to space conditions for 18 months, the samples were returned to Earth and analyzed in the laboratory for reactions caused by solar UV and cosmic radiation. Chemical degradation and possible racemization and oligomerization, the main reactions caused by photochemistry in the vacuum ultraviolet domain (VUV, wavelength range 100-200?nm for photon energy from 6.2 to 12.4?eV) were examined in particular. The molecules were extracted and derivatized by silylation and analyzed by gas chromatograph coupled to a mass spectrometer (GC-MS) to quantify the rate of the degradation of the compounds. Laboratory exposure in several wavelength ranges from UV to VUV was carried out in parallel in the Cologne Deutsches Zentrum für Luft- und Raumfahrt (DLR) Center and Centre de biophysique moléculaire (CBM) laboratories. The results show that resistance to irradiation is a function of the chemical nature of the exposed molecules and the wavelengths of the UV light. The most altered compounds were the dipeptide, aspartic acid, and aminobutyric acid. The most resistant were alanine, valine, glycine, and aminoisobutyric acid. Our results also demonstrate the protective effect of meteorite powder, which reemphasizes the importance of exogenic contribution to the inventory of prebiotic organics on early Earth. 相似文献
7.
分析了空间作战融合网电作战力量的趋势,并结合空间作战的网电对抗对航天器网电攻防的功能需求,分析了可行的航天器系统实现网电对抗功能的技术途径,包含航天器融合网电作战力量的技术能力和可能系统组成。 相似文献
8.
The NASA/White House Vision for Space Exploration is primarily focused on the development of human and robotic systems that will enable ‘discovery-driven’ investigations in areas important to the scientific community: Mars, the solar system's outer moons, and planets orbiting other stars. Such a portfolio can only be realized if NASA is prepared to target investment at opportunities that are most scientifically compelling. NASA's leaders will have to make decisions in subjective and uncertain environments about the relative long-term value of different kinds of scientific discoveries seen as equally important to different groups. A management paradigm of this kind will imply assessment of heterogeneous priorities and management of interdependent and changing requirements. In order to identify the basis and implications of a ‘discovery-driven’ paradigm, this paper surveys the relationship between the Vision's principles and its programmatic content, the objectives of the Vision's scientific focus areas and their interrelationships, and the public context in which science-focused exploration will proceed. 相似文献
10.
Since 1988 high sensitivity semiconductor dosimeter-radiometer “Liulin” worked on board of MIR space station. Device measured the absorbed dose rate and the flux of penetrating particles. The analysis of the data hows the following new results: In October 1989 and after March 24, 1991, two additional stable maximums in flux channel were observed in the southern-eastern part of South Atlantic Anomaly (SAA). These two maximums existed at least several months and seem to be due to trapped high energy electron and proton fluxes. In April 1991 additional maximums were localized in the following geographical coordinates regions: LATITUDE = (−35 °)–(−50 °) LONGITUDE = 332 ° − 16 ° and lat.(−46 °)–(−52 °) long. 360 ° − 60 °. Additional maximums diffusion occurs inside radiation belt. Appearance of these maximums seems to be closely connected with preceding powerful solar proton events and associated geomagnetic dynamics of new belt disturbances. After the series of solar proton events in June 1991 we observed significant enhancement of this new radiation belt formation. To achieve sufficient accuracy of dose rate predictions in low Earth orbits the structure and dynamics of new belt should be carefully analyzed to be included in a new environment model. From the inter comparison of the data from “Liulin” and French developed tissue equivalent LET spectrometer NAUSICAA in the time period August–November 1992 we come to the following conclusions: Mainly there is good agreement between both data sets for absorbed dose in the region of SAA; Different situation of the instruments on the station can explain the cases when differences up to 2 times are observed; At high latitudes usually the tissue equivalent absorbed dose observations are 2 times larger than “Liulin” doses. 相似文献
11.
Space-Station technology, micron-thick 100-m solar sails, and a near-Earth propulsion system allow exploration of small, dark Near-Earth-Objects (NEO's) of cometary origin. Early crewed missions to NEO's could analyze the objects' properties and evaluate resource-mining possibilities. Later missions to Earth-threatening 100-m radius NEO's could deploy NEO-centered, high-area, low-mass reflective structures. The solar gravitational parameter (GM sun) on a NEO is slightly reduced by increased radiation pressure. The central-force-field equations reveal that NEO eccentricity and average solar distance are thereby slightly increased. Given decades of warning and long-lived reflective canopies, such structures can convert Earth-impacts into near-misses. Although not suitable for NEO mining, such structures are superior to nuclear detonations because (as revealed by the 1994 Jupiter-comet interaction) NEO calving may be a consequence of explosions. NEO despinning is not required. 相似文献
12.
自动紧急关机系统是火箭动力系统试验的关键环节,是推进系统和试验台的有力安全保障。针对液氧/煤油动力系统热试车威力大、响应快的系统特性,研发了基于VXI的数据采集系统及紧急关机系统,依据功能需求设计开发了基于VC++的关机判读软件。首先设计了关机判读软件系统的采集、报警、实时存储、图像显示等基本功能模块,其次阐述了基于VC++的关机判读软件的具体实施方案,包括软件应用环境和核心程序流程,展示了关机判读软件的应用主界面;详细分析了影响自动关机响应时间的主要因素;通过一百多组模拟数据进行了软件功能性、故障检测能力等多方面的测试,实时性和准确度均达到了系统设计要求。某次液氧/煤油动力系统热试车对本系统的应用进一步验证了其性能的优异性。 相似文献
13.
网电一体战的作战目标是破坏和控制敌方的信息基础和战略命脉,摧毁和致瘫敌方的作战指挥控制系统.分析了网电空间战的一般特点和军事特点,并结合网电攻击的案例分析了其对未来防空战争的影响,其影响主要表现在:作战空间由“地表维”和“垂直维”延伸至“网电维”,利用和控制网电空间将成为未来防空作战的主题,网电空间对抗成为提升未来防空作战能力的核心. 相似文献
14.
This new ethological study focuses on the co-adaptation of the crew's spatial behavior to social isolation in a polar base thus simulating long-term living and working of a space team. The method consisted in drawing the subjects' position (n=13) on an observation map at the midday and evening meals at the Dumont d'Urville French station in Antarctica, daily during the summer campaigns and weekly during the winter-over of the TA46 mission. Quantitative data are presented in geocentric (positions), allocentric (distances) and egocentric (orientations) analyses with an emphasis on three adaptative periods (first 3 months, intermediary 2 months and last 3 months of isolation). Results show a large space occupancy during the first week after arrival and the last week before departure from the polar base, and a team-members' grouping during the winter-over. On the over-all time, the inter-individual distances increase. The social orientations are higher at the beginning than at the end of the mission. Discussion underlies the pertinent use of such ethological indicators collected from polar stations as predictors of well-being and optimal-working of the future orbital and planetary stations users. 相似文献
17.
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
20.
This paper presents the study of a concept of Ariane-5 evolution by means of replacement of two solid-propellant boosters EAP with two liquid-propellant reusable fly-back boosters (RFBBs) called “Bargouzine”. The main design feature of the reference RFBB is LOX/LH2 propellant, the canard aerodynamic configuration with delta wings and rocket engines derived from Vulcain-2 identical to that of the central core except for the nozzle length. After separation RFBBs return back by use of air breathing engines mounted in the aft part and then landing on a runway.The aim of the study is a more detailed investigation of critical technology issues concerning reliability, re-usability and maintenance requirements. The study was performed in three main phases: system trade-off, technical consolidation, and programmatic synthesis. The system trade-off includes comparative analysis of two systems with three and four engines on each RFBB and determination of the necessary thrust level taking into account thrust reservation for emergency situations. Besides, this phase contains trade-off on booster aerodynamic configurations and abort scenario analysis.The second phase includes studying of controllability during the ascent phase and separation, thermo-mechanical design, development of ground interfaces and attachment means, and turbojets engine analysis taking into account reusability. 相似文献
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