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1.
空间物理学是人类进入空间时代后迅速发展的一门新兴交叉学科,特别是进入新世纪后国内外都取得了辉煌的成就.本文简要介绍空间物理领域近年来取得的重要进展、重要成果、国内外发展趋势,以及未来发展的重点方向.  相似文献   

2.
As we celebrate the centennial year of the discovery of cosmic rays on a manned balloon, it seems appropriate to reflect on the evolution of ballooning and its scientific impact. Balloons have been used for scientific research since they were invented in France more than 200 years ago. Ballooning was revolutionized in 1950 with the introduction of the so-called natural shape balloon with integral load tapes. This basic design has been used with more or less continuously improved materials for scientific balloon flights for more than a half century, including long-duration balloon (LDB) flights around Antarctica for the past two decades. The U.S. National Aeronautics and Space Administration (NASA) is currently developing the next generation super-pressure balloon that would enable extended duration missions above 99.5% of the Earth’s atmosphere at any latitude. The Astro2010 Decadal Survey report supports super-pressure balloon development and the giant step forward it offers with ultra-long-duration balloon (ULDB) flights at constant altitudes for about 100 days.  相似文献   

3.
Human missions to Mars are planned to happen within this century. Activities associated therewith will interact with the environment of Mars in two reciprocal ways: (i) the mission needs to be protected from the natural environmental elements that can be harmful to human health, the equipment or to their operations; (ii) the specific natural environment of Mars should be protected so that it retains its value for scientific and other purposes. The following environmental elements need to be considered in order to protect humans and the equipment on the planetary surface: (i) cosmic ionizing radiation, (ii) solar particle events; (iii) solar ultraviolet radiation; (iv) reduced gravity; (v) thin atmosphere; (vi) extremes in temperatures and their fluctuations; and (vii) surface dust. In order to protect the planetary environment, the requirements for planetary protection as adopted by COSPAR for lander missions need to be revised in view of human presence on the planet. Landers carrying equipment for exobiological investigations require special consideration to reduce contamination by terrestrial microorganisms and organic matter to the greatest feasible extent. Records of human activities on the planet's surface should be maintained in sufficient detail that future scientific experimenters can determine whether environmental modifications have resulted from explorations.  相似文献   

4.
A more flexible policy basis from which to manage our planet in the 21st century is desirable. As one contribution, we note that synergies between space exploration and the preservation of our habitat exist, and that protecting life on Earth requires similar concepts and information as investigations of life beyond the Earth, including the expansion of human presence in space. Instrumentation and data handling to observe both planetary objects and planet Earth are based on similar techniques. Moreover, while planetary surface operations are conducted under different conditions, the technology to probe the surface and subsurface of both the Earth and other planets requires similar tools, such as radar, seismometers, and drilling devices. The Earth observation community has developed some exemplary tools and has featured successful international cooperation in data handling and sharing that could be equally well applied to robotic planetary exploration. Here we propose a network involving both communities that will enable the interchange of scientific insights and the development of new policies and management strategies. Those tools can provide a vital forum through which the management of this planet can be assisted, and in which a new bridge between the Earth-centric and space-centric communities can be built.  相似文献   

5.
The 20th century temperature anomaly record is reproduced using an energy balance model, with a diffusive deep ocean. The model takes into account all the standard radiative forcings, and in addition the possibility of a non-thermal solar component. The model is parameterized and then optimized to produce the most likely values for the climate parameters and radiative forcings which reproduce the 20th century global warming. We find that the best fit is obtained with a negligible net feedback. We also show that a non-thermal solar component is necessarily present, indicating that the total solar contribution to the 20th century global warming, of ΔTsolar = 0.27 ± 0.07 °C, is much larger than can be expected from variation in the total solar irradiance alone. However, we also find that the largest contribution to the 20th century warming comes from anthropogenic sources, with ΔTman = 0.42 ± 0.11 °C.  相似文献   

6.
The ancient Greek astronomical calculator known as the Antikythera Mechanism has been analyzed using geometrical, calculus, trigonometric and complex variable methods. This analysis demonstrates that the Mechanism modeled the variations in the Moon’s angular velocity as seen from the Earth, to better than 1 part in 200. A major implication of this analysis is that the Antikythera Mechanism of the 2nd century BCE modeled the anomalistic motion of the Moon more accurately than Ptolemy’s account of Hipparchus’s theory of the 2nd century CE. In the present work, mathematics, astronomy, history and methodology of the sciences combine in the study of a unique artifact, preserved for posterity in an ancient ship that sank in the Mediterranean 2100 years ago and recovered by Greek sponge divers at the dawn of the 20th century.  相似文献   

7.
8.
临近空间科学探测数据的共享与实践   总被引:1,自引:1,他引:0       下载免费PDF全文
为促进鸿鹄专项临近空间科学探测数据资源的有效应用,为国家科学数据资源增加新的数据成员,开展临近空间科学探测数据共享相关技术研究.依据相关元数据国家标准与规范,借鉴参考多个领域科学数据元数据的构建方法,通过分析临近空间科学探测数据的数据特征,研究设计了符合临近空间科学探测数据共享需求的核心元数据模型,从不同角度描述了临近空间科学探测数据的数据特征和用户访问数据时所关心信息,并基于该模型实现了临近空间科学探测数据资源目录服务,设计了临近空间科学探测数据共享服务平台,实现了临近空间科学探测数据的归档管理和共享分发,为使用鸿鹄专项数据开展科学研究和有效应用提供了有效支撑.   相似文献   

9.
空间科学实验柜被动式减振系统研究   总被引:2,自引:0,他引:2  
载人航天二期我国将发展短期有人照料的空间实验室,将开展一系列空间科学实验.国际空间站和我国神舟飞船实际微重力水平测量结果表明,需采取必要的减振措施才能满足特殊科学实验要求,鉴于此对空间科学实验柜被动式减振系统进行了研究和设计.根据空间科学实验柜在载人航天器内的实际安放状态,对其进行了减振布局.将实验柜本身作为刚体,建立6自由度的减振系统动力学模型,然后在ADAMS中建立了空间科学实验柜及减振系统三维实体模型,对减振系统进行仿真,得出系统时域、频域及随机输入下的响应特性.对减振系统参数进行优化,提高了系统的减振效果.   相似文献   

10.
双星/GIS组合定位建模与仿真   总被引:4,自引:1,他引:4  
双星定位系统具有快速高精度定位和简短报文通信的功能.为了进一步提高定位精度,满足特殊用户需要,文中提出了由双星和道路地理信息系统组合定位的新方法,并做了计算机仿真试验,进行了组合定位精度分析.分析结果表明,该方法可明显提高双星定位精度,在适当条件下组合定位均方差小于10m。  相似文献   

11.
The design and operation of a high altitude scientific balloon requires adequate knowledge of the thermal characteristics of the balloon to make it safe and reliable. The thermal models and dynamic models of altitude scientific balloons are established in this paper. Based on the models, a simulation program is developed. The thermal performances of a super pressure balloon are simulated. The influence of film radiation property and clouds on balloon thermal behaviors is discussed in detail. The results are helpful for the design and operate of safe and reliable high altitude scientific balloons.  相似文献   

12.
“嫦娥4号”任务有效载荷系统设计与实现   总被引:3,自引:2,他引:1  
"嫦娥4号"任务将首次实现人类在月球背面软着陆。通过分析任务特点,以多类型有效载荷配置为背景,介绍了以科学目标和探测任务为核心的有效载荷系统设计思路和实现方法。同时针对首次在深空探测领域搭载国际合作有效载荷项目情况进行了说明。"嫦娥4号"任务最重要的科学目标是利用月球背面洁净的电磁环境进行天文低频射电观测,因此分别在着陆器和中继星上新增配置了国内新研制的低频射电频谱仪及荷兰研制的低频探测仪。科学探测的太阳爆发产生的低频电场信号极其微弱,如何消除着陆器和中继星上其他电子设备发射的近场噪声对远场探测信号的干扰就成了本次任务的最大难点。在相关研制单位的多方努力下,通过优化接收天线设计和地面数据处理算法等多种手段,实现了低频探测信号不低于30 d B的噪声抑制性能,具备了实现科学目标的能力。  相似文献   

13.
世界航空动力技术的现状及发展动向   总被引:43,自引:1,他引:43  
讲述了喷气战斗机动力的发展历程.推重比8一级发动机是目前世界各发达国家现役主战机种的动力,配装推重比10一级发动机的第4代战斗机预计在2003~2007年后陆续装备使用,成为美国、部分西方国家甚至我国部分周边国家和地区2010年后的主战机种.概括了民用涡扇发动机和直升机动力的发展及其主要关键技术.列举了21世纪航空动力主要关键技术的发展方向.  相似文献   

14.
在科学研究领域, 存储容量、处理效率和分析精度并不能适应科学数据的指数级增长速度。通过对科学数据结构与标准的研究, 提出了一个海量科学数据计算框架BSDF。提出了一种基于模型驱动的统一数据接口, 实现对异构科学数据的无差别访问;提出了一种基于元数据的自动分区算法, 通过参数预取与超平面维度计算确定任务颗粒度。实验结果表明:与H5Spark科学数据计算框架的基于9项基准测试的性能相比, BSDF计算框架提升了39%~68%;在特定领域PKTM的算法优化上, BSDF达到了41.62倍的加速比。   相似文献   

15.
小行星探测科学目标进展与展望   总被引:1,自引:0,他引:1       下载免费PDF全文
由于较好地保留了太阳系早期形成和演化历史的遗迹,小行星,尤其是近地小行星,已成为国际深空探测领域的研究热点。介绍了小行星的定义、分类和主要探测方式,指出目前小行星探测已进入空间探测的新时代;总结了国际小行星探测的现状,包括已实施和正在实施的小行星探测任务的科学目标、科学载荷配置,以及获取的主要科学数据等;探讨了未来小行星探测的发展趋势和主要科学问题,并对我国未来自主小行星探测任务科学目标的制定进行了展望。  相似文献   

16.
The time has come to give serious thought to the use of the International Space Station (ISS) as a space platform to advance remote sensing research in several scientific disciplines. The European scientific community has been developing instrumentation for deployment on the ISS for some time now. Recently, NASA opened competitions for scientific programs to be supported as “Missions of Opportunity” to utilize the “EXPRESS Pallet” facility on the ISS. A single EXPRESS Pallet has the capability of carrying a collection of instruments similar to the payload of a conventional satellite. A major difference between ISS and satellite programs is that the research funding will be expended on scientific instrumentation and analysis and not on a spacecraft, launch vehicle, and flight operations. As the ISS becomes fully operational, EXPRESS Pallets could be deployed in short periods of time compared to preparing a satellite program. The ability to retrieve, improve, and re-fly an instrument is important to a progressive research program. This allows the experiment to be responsive to data analysis in a timely manner and also keep pace with developing technology.  相似文献   

17.
航天器环境工程回顾与展望   总被引:2,自引:0,他引:2  
文章回顾了 2 0世纪航天器环境工程发展的三个主要方面 :在航天器研制中 ,环境工程和环境试验起着重要的作用 ,是验证工作的主要组成部分 ;环境效应、环境模拟试验方法等方面的研究则是环境工程的基础 ;而计算机和数字技术大大促进了整个环境工程和试验技术的发展。在新的世纪 ,环境工程的发展在继续努力降低环境试验的费用和时间的同时 ,提高环境试验的效果 ,使整个环境工程对保证航天器可靠性起到更重要的作用。文章提出了中国在 2 1世纪发展航天器环境工程需要努力的若干方面。  相似文献   

18.
SMILE (Solar wind Magnetosphere Ionosphere Link Explorer) mission is a joint ESA-CAS space science project. The working orbit is a 19 Re 5000 km HEO with 4 scientific instruments:Soft X-ray Imager(SXI), Ultra-Violet Imager (UVI), Magnetometer (MAG) and Light Ion Analyzer (LIA). SMILE aims to understand the interaction between the solar wind and the Earth's magnetosphere through the images of SXI and UVI and in-situ measurement from LIA and MAG. After the kick-off in 2016, the SMILE project went to Phase A study. The mission adoption is scheduled for November 2018, with a target launch date in 2022-2023. In this paper, the background of the mission, scientific objectives, the design and characteristics of scientific instruments and the mission outline will be introduced in details.   相似文献   

19.
The efforts in scientific ballooning in India have always been focussed towards continuous upgrading of capabilities in all aspects of balloon flights - balloon material, balloon fabrication, launch techniques, heavy payload launch, telemetry, telecommand and other ground facilities - to meet the growing demands of the scientific community. A brief account of recent progress in several of these aspects and future plans for further improvements in scientific ballooning capability is presented.  相似文献   

20.
CNES (Centre National d'Études Spatiales) acts, since its creation in 1961, as the French Space Agency and is a key leader in space research, and scientific and technical developments. Its involvement in a broad range of programs has positioned CNES as one of the most relevant national research agencies, leading efforts and initiatives in both European and international contexts. This article provides a review and analysis of the scientific and technical production of CNES, using as input the papers written by CNES staff referenced in the Scopus database. The period under study dates to 1964 and includes more than 10.000 documents. The study analyses measurable characteristics of CNES documents’ production: productivity, collaboration, and impact through citations. This paper provides a contribution aimed to gain a better understanding and characterisation of the scientific activity completed by Space agencies.  相似文献   

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