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Solar proton events recorded in the stratosphere during cosmic ray balloon observations in 1957–2008
G.A. Bazilevskaya V.S. MakhmutovY.I. Stozhkov A.K. SvirzhevskayaN.S. Svirzhevsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Long-term balloon observations have been performed by the Lebedev Physical Institute since 1957 up to the present time. The observations are taken several times a week at the polar and mid latitudes and allow us to study dynamics of galactic and solar cosmic ray as well as secondary particle fluxes in the atmosphere and in the near-Earth space. Solar energetic particles (120) – mostly protons – (SEP) events with >100 MeV proton intensity above 1 cm−2 s−1 s−1 were recorded during 1958–2006. Before the advent of the SEP monitoring on spacecraft these results constituted the only homogeneous series of >100 MeV SEP events. The SEP intensities and energy spectra inferred from the Lebedev Physical Institute observations are consistent with the results taken in the adjacent energy intervals by the spacecraft and neutron monitors. Joint consideration of the SEP events series recorded by balloons and by neutron monitors during solar cycles 20–23 makes it possible to restore the probable number of events in solar cycle 19, which was not properly covered by observations. Some correlation was found between duration of SEP event production in a solar cycle and sunspot cycle characteristics. 相似文献
85.
M.N. Gousheva R.P. Glavcheva D.L. Danov P.L. Hristov B.B. Kirov K.Y. Georgieva 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
The problem of earthquake prediction has stimulated the search for a correlation between seismic activity and ionospherical anomalies. We found observational evidence of possible earthquake effects in the near-equatorial and low latitude ionosphere; these ionospheric anomalies have been proposed by Gousheva et al. [Gousheva, M., Glavcheva, R., Danov, D., Angelov P., Hristov, P., Influence of earthquakes on the electric field disturbances in the ionosphere on board of the Intercosmos-Bulgaria-1300 satellite. Compt. Rend. Acad. Bulg. Sci. 58 (8) 911–916, 2005a; Gousheva, M., Glavcheva, R., Danov, D., Angelov, P., Hristov, P., Kirov, B., Georgieva, K., Observation from the Intercosmos-Bulgaria-1300 satellite of anomalies associated with seismic activity. In: Poster Proceeding of 2nd International Conference on Recent Advances in Space Technologies: Space in the Service of Society, RAST ‘2005, June 9–11, Istanbul, Turkey, pp. 119–123, 2005b; Gousheva, M., Glavcheva, R., Danov, D., Angelov, P., Hristov, P., Kirov, B., Georgieva, K., Satellite monitoring of anomalous effects in the ionosphere probably related to strong earthquakes. Adv. Space Res. 37 (4), 660–665, 2006]. This paper presents new results from observations of the quasi-static electric field and ion density on board INTERCOSMOS-BULGARIA-1300 satellite in the mid latitude ionosphere above sources of moderate earthquakes. Data from INTERCOSMOS-BULGARIA-1300 satellite and seismic data (World Data Center, Denver, Colorado, USA) for magnetically quiet and medium quiet days are juxtaposed in time-space domain. For satellite’s orbits in the time period 15.09–01.10.1981 an increase in the horizontal and vertical components of the quasi-static electric field and fluctuations of the ion density are observed over zones of forthcoming seismic events. Some similar post effects are observed too. The emphasis of this paper is put on the anomalies which specify the mid latitude ionosphere. The obtained results contain important information because they confirm our previous results for near-equatorial and low latitude regions. 相似文献
86.
对地观测卫星总体参数多学科优化 总被引:7,自引:2,他引:5
针对对地观测卫星总体参数设计问题,建立了以对地观测性能最佳为目标的多学科优化模型,考虑姿轨控制、电源、结构、推进、有效载荷5个分系统的设计变量和相应约束条件,并考虑运载火箭对卫星设计的约束条件,通过经验公式建立分析模型.采用协同优化方法,利用外点罚函数法将系统级优化问题转化为无约束优化问题以改善协同优化系统级的数值缺陷,建立了多学科设计优化框架.计算结果表明通过优化可提升卫星的对地观测性能,验证了该方法的合理性.建模思路与优化方法可望用于更贴合工程实际的卫星参数设计. 相似文献
87.
神舟七号微小卫星伴随飞行技术试验 总被引:2,自引:0,他引:2
神舟七号 (SZ-7) 载人航天任务中释放的一颗微小伴随卫星 (BX-1), 首次开展了卫星在轨释放、对飞船观测和对轨道舱接近及绕飞等技术试验. 该卫星首次进行了GaInP2/GaAs/Ge 中国产太阳电池阵、锂离子蓄电池、微型液氨推进模块、小型化姿态跟踪控制模块、双焦距一体化可见光相机及小型化USB 测控应答机等技术验证. 本文介绍了SZ-7 微小卫星的设计方案, 讨论了形成稳定伴随飞行的轨道设计等技术, 并根据卫星在轨运行情况对试验任务进行了评价. 相似文献
88.
本文从跑道必须配置的自动气象观测系统(AWOS)入手,主要从四个方面对多跑道(两条或以上)运行下的航空气象服务进行了探讨。一是主要与航空气象人员对外服务有关,如本场天气报告(METAR、SPECI)中数据采集基准点的选择、跑道视程的显示、修正海平面气压采集等的归纳;二是管制部门、机场等用户所需要的相关气象数据信息显示方式、更新速率及如何理解等;三是探讨如何为多跑道运行提供精细化、临近的预报技术支持;最后,本文对航站自动情报服务系统(ATIS)中气象报告种类的选取及注意事项进行了探讨,指出该系统目前存在的问题和需要改进的地方。 相似文献
89.
风云卫星是我国民用遥感卫星中应用范围最广泛、成效最为显著的卫星系列之一,在推动国民经济发展和加强装备自主建设等方面发挥了重要作用。面向气象高质量发展、防灾减灾、应对气候变化、生态文明建设和国家安全等多重挑战,风云卫星将坚持创新驱动发展战略,以体系化、智能化为主要发展方向,突破平台和载荷关键技术,构建智慧协同观测体系。本文探讨了风云卫星智慧协同观测体系在气象综合观测效能提升、体系化智能化网络赋能及全方位环境保障等方面的必要性,在分析国内外气象卫星发展历程的基础上,提出了新一代风云气象卫星构建智慧协同观测体系的建设思路和初步方案,并对体系构建中的关键技术进行了分析。最后,展望了风云卫星智慧协同观测体系的应用前景。 相似文献
90.
Gordon Chin Scott Brylow Marc Foote James Garvin Justin Kasper John Keller Maxim Litvak Igor Mitrofanov David Paige Keith Raney Mark Robinson Anton Sanin David Smith Harlan Spence Paul Spudis S. Alan Stern Maria Zuber 《Space Science Reviews》2007,129(4):391-419
NASA’s Lunar Precursor Robotic Program (LPRP), formulated in response to the President’s Vision for Space Exploration, will
execute a series of robotic missions that will pave the way for eventual permanent human presence on the Moon. The Lunar Reconnaissance
Orbiter (LRO) is first in this series of LPRP missions, and plans to launch in October of 2008 for at least one year of operation.
LRO will employ six individual instruments to produce accurate maps and high-resolution images of future landing sites, to
assess potential lunar resources, and to characterize the radiation environment. LRO will also test the feasibility of one
advanced technology demonstration package. The LRO payload includes: Lunar Orbiter Laser Altimeter (LOLA) which will determine
the global topography of the lunar surface at high resolution, measure landing site slopes, surface roughness, and search
for possible polar surface ice in shadowed regions, Lunar Reconnaissance Orbiter Camera (LROC) which will acquire targeted
narrow angle images of the lunar surface capable of resolving meter-scale features to support landing site selection, as well
as wide-angle images to characterize polar illumination conditions and to identify potential resources, Lunar Exploration
Neutron Detector (LEND) which will map the flux of neutrons from the lunar surface to search for evidence of water ice, and
will provide space radiation environment measurements that may be useful for future human exploration, Diviner Lunar Radiometer
Experiment (DLRE) which will chart the temperature of the entire lunar surface at approximately 300 meter horizontal resolution
to identify cold-traps and potential ice deposits, Lyman-Alpha Mapping Project (LAMP) which will map the entire lunar surface
in the far ultraviolet. LAMP will search for surface ice and frost in the polar regions and provide images of permanently
shadowed regions illuminated only by starlight. Cosmic Ray Telescope for the Effects of Radiation (CRaTER), which will investigate
the effect of galactic cosmic rays on tissue-equivalent plastics as a constraint on models of biological response to background
space radiation. The technology demonstration is an advanced radar (mini-RF) that will demonstrate X- and S-band radar imaging
and interferometry using light weight synthetic aperture radar. This paper will give an introduction to each of these instruments
and an overview of their objectives. 相似文献