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1.
首先根据载人航天器轨道运行段的基本特征,利用球面三角公式推导了:①阳光方向与载人航天器太阳能帆板法向的最佳夹角公式;②圆轨道的受晒因子公式。然后根据理论分析,引入帆板的效率系数。最后借助于计算机代数mathematica系统,建立了一种分析帆板最佳受晒的直观、清晰、简便的方法。所得的结论为确定载人航天器的发射窗口提供了依据。  相似文献   

2.
Dynamic processes in the interplanetary space have been investigated using time variations in time parameters of the cosmic-ray rigidity spectrum. Change of heliosphere electromagnetic characteristics has been found out to precede sporadic phenomena on the Sun. In particular, it is shown that sporadic phenomena are followed by generation of local polarization electric fields, decrease of the magnetic-field strength in small-scale heliospheric structures, and increase of the potential difference between the pole and the plane of the ecliptic. These features allow prediction of solar proton events in advance (from several hours to several tens of hours) with a high degree of confirmation.  相似文献   

3.
介绍了南大西洋异常区的辐射环境及其特点,重点研究了发生于2000年7月14日的太阳质子事件对太阳同步轨道空间环境造成的影响,太阳质子事件期间,抵达近地空间的高能电子、质子及重离子对太阳同步轨道空间环境造成剧烈地扰动,并且不同种类不同能量的粒子扰动特征不尽相同。  相似文献   

4.
选用NOAA提供的太阳质子事件表以及SGD发表的与其相关的射电多波段的观测资料进行了统计分析,试图从厘米波,毫米波爆发与质子事件的关系上寻找规律,从而获得一些有意义的结果.   相似文献   

5.
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The Advanced Space-based Solar Observatory (ASO-S) was formally approved at the end of 2017. In the past two years, ASO-S underwent its official Phase-B and Phase-C studies. The Phase-B study was successfully accomplished by the end of April 2019, and the Phase-C study is being now undertaken until August 2020. Then the flight model is planned to finish within 16 months. Around the end of 2021, ASO-S will be ready in the launch state. We briefly summarize the history of ASO-S, the phase-B studies, and the phase-C studies.  相似文献   

6.
    
Peak fluxes are an important property of gradual solar energetic particle (SEP) event time profiles from both astro/heliophysical and applications perspectives. However, the peak flux in an event may occur at the event onset, or at the time of the interplanetary shock arrival (the ESP or energetic storm particles). This makes an important difference in the interpretation of the peak flux, and in any attempts to characterize or model it. This paper describes a study of SEP data sets from ACE, IMP-8 and GOES toward determining the relative properties of these peak fluxes for protons with energies near 1, 10, and 50 MeV. The results suggest that for gradual events with both peaks, the ESP peak often dominates at 1 MeV energies and is dominant about half the time at 10 MeV. Moreover, the prompt peak fluxes can be used to estimate the shock peak (ESP event) up to days ahead, especially in the lower energy range.  相似文献   

7.
我国“风云一号(B)”气象卫星于1990年9月3日发射入轨,该星载有粒子成分监测器,用来探测空间粒子辐射环境,其中包括测量太阳耀斑时产生的太阳质子事件及其重粒子丰度;银河宇宙线异常成分与强度;内辐射带磁异常区的粒子通量及重粒子成分,“风云一号(B)”卫星运行半年来,我们已获取了上述有关的粒子辐射资料,在卫星上获得这些资料在我国尚属首次,本文主要分析观测到的太阳质子事件。  相似文献   

8.
We performed a search for ground level solar cosmic ray enhancements on the full five minute database of the Mexico City neutron monitor using wavelet filters and two different statistical tests. We present a detailed analysis of the time series of November 2, 1992, where we found a previously unreported increment matching the onset time of the impulsive phase of GLE 54, thus providing evidence of an effective detection of high energy solar cosmic rays.  相似文献   

9.
Based on the author’s experience in ISO TC20/SC14 Working Group 4, this paper discusses the common problems encountered when developing a standard for solar energetic particle (SEP) fluxes. The problem involving the reliability of the distribution function describing the SEP events and the interpolation of this function into the region of not-yet-observed large events are discussed. The problems with describing the fluences of SEPs over a wide range of energy in the form of energetic spectra are analyzed. Requirements for SEP flux models are formulated. The reliability of some SEP flux models is determined by comparing their predictions with the experimental data.  相似文献   

10.
影响地球环境的太阳质子事件的时间过程   总被引:1,自引:0,他引:1  
利用1966年以来的大量太阳耀斑以及相应质子事件的资料,分析研究了质子事件到达时间和极大时间同耀斑经度位置的统计关系.结果表明当耀斑位置处于经过地球的行星际大尺度场磁力线足点位置附近时,上述两种时间过程最短.这个结果支持了太阳耀斑粒子经日冕传播再向行星际空间传播的二阶段传播模型.  相似文献   

11.
    
Observed galactic cosmic ray intensity can be subjected to a transient decrease. These so-called Forbush decreases are driven by coronal mass ejection induced shockwaves in the heliosphere. By combining in situ measurements by space borne instruments with ground-based cosmic ray observations, we investigate the relationship between solar energetic particle flux, various solar activity indices, and intensity measurements of cosmic rays during such an event. We present cross-correlation study done using proton flux data from the SOHO/ERNE instrument, as well as data collected during some of the strongest Forbush decreases over the last two completed solar cycles by the network of neutron monitor detectors and different solar observatories. We have demonstrated connection between the shape of solar energetic particles fluence spectra and selected coronal mass ejection and Forbush decrease parameters, indicating that power exponents used to model these fluence spectra could be valuable new parameters in similar analysis of mentioned phenomena. They appear to be better predictor variables of Forbush decrease magnitude in interplanetary magnetic field than coronal mass ejection velocities.  相似文献   

12.
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The Solar Polar ORbit Telescope (SPORT) project for space weather mission has been under intensive scientific and engineering background studies since it was incorporated into the Chinese Space Science Strategic Pioneer Project in 2011.SPORT is designed to carry a suite of remote-sensing and in-situ instruments to observe Coronal Mass Ejections (CMEs),energetic particles,solar high-latitude magnetism,and the fast solar wind from a polar orbit around the Sun. The first extended view of the polar regions of the Sun and the ecliptic enabled by SPORT will provide a unique opportunity to study CME propagation through the inner heliosphere,and the solar high-latitude magnetism giving rise to eruptions and the fast solar wind.Coordinated observations between SPORT and other spaceborne/ground-based facilities within the International Living With a Star (ILWS) framework can significantly enhance scientific output.SPORT is now competing for official selection and implementation during China's 13th Five-Year Plan period of 2016-2020.  相似文献   

13.
通过对0°W-39°W,40°W-70°W,71°W-90°W经度范围内太阳质子事件与太阳耀斑的相关性计算分析,发现太阳质子事件与太阳耀斑的相关系数依赖于经度.太阳耀斑积分与地球磁链接区域(40°W-70°W)太阳质子事件强度的相关系数最大.相关系数的这种特点与耀斑加速粒子的最大流量只出现在磁链接区域的特征相吻合.计算结果表明,太阳耀斑对太阳质子事件具有贡献,即耀斑对E ≥ 10MeV的质子加速有贡献.耀斑和CME在磁链接区域对太阳质子事件的贡献相同,这说明太阳质子事件是混合型事件.  相似文献   

14.
选取第23太阳活动周(1997—2006年)期间542例由太阳爆发活动驱动的行星际激波事件,分析确定了太阳源头和行星际空间中影响行星际激波能否到达地球轨道的关键物理参数;在此基础上,建立了预测行星际激波能否到达地球的新预报模型(EdEaSPM). 回溯预报结果表明,EdEaSPM模型的预报成功率约为66%,略高于国际一流预报模型的预报成功率;EdEaSPM模型的虚报率未超过50%,改善了当前国际主流模型虚报率较大的情况;对于偏度指标,虽然当前所有模型的偏度值均大于1,但EdEaSPM模型的偏度值最接近于1且明显小于其他模型的偏度值;EdEaSPM模型的其他评价指标也都高于国际主流模型的相应指标. 此外,选取2012年期间的激波事件对EdEaSPM模型进行了预报检验,预测结果与实际情况吻合. EdEaSPM模型不仅能够提前约1~3天进行预报,而且预报效果与国际一流模型具有可比性,尤其是在提高预报成功率及降低虚报率方面具有一定优势.  相似文献   

15.
太阳质子事件中短期预报模型研究   总被引:2,自引:0,他引:2       下载免费PDF全文
太阳质子事件通量的预测对航天器抗辐射加固设计和航天员出舱活动具有非常重要的意义.针对一年以下的航天任务,利用经验统计方法,确认太阳活跃年和太阳平静年期间,1——365天不同时间段内 > 10MeV,> 30MeV和 > 60MeV的太阳质子事件积分通量符合对数正态分布,且通量对数的标准偏差σ和期望值μ随任务期时间的变化满足对数函数形式.以此为基础,构建太阳质子通量的中短期预报模型.该模型能够针对太阳活跃年和太阳平静年,给出一定置信度下1——365天不同时间内 > 10MeV,> 30MeV和 > 60MeV的质子事件通量分布,从而为执行中短期航天任务提供太阳质子事件通量的预测,以规避不必要的风险.  相似文献   

16.
Due to high relative velocities, collisions of spacecraft in orbit with Space Debris (SD) or Micrometeoroids (MM) can lead to payload degradation, anomalies as well as failures in spacecraft operation, or even loss of mission. Flux models and impact risk assessment tools, such as MASTER (Meteoroid and Space Debris Terrestrial Environment Reference) or ORDEM (Orbital Debris Engineering Model), and ESABASE2 or BUMPER II are used to analyse mission risk associated with these hazards. Validation of flux models is based on measured data. Currently, as most of the SD and MM objects are too small (millimeter down to micron sized) for ground-based observations (e.g. radar, optical), the only available data for model validation is based upon retrieved hardware investigations e.g. Long Duration Exposure Facility (LDEF), Hubble Space Telescope (HST), European Retrievable Carrier (EURECA). Since existing data sets are insufficient, further in-situ experimental investigation of the SD and MM populations are required. This paper provides an overview and assessment of existing and planned SD and MM impact detectors. The detection area of the described detectors is too small to adequately provide the missing data sets. Therefore an innovative detection concept is proposed that utilises existing spacecraft components for detection purposes. In general, solar panels of a spacecraft provide a large area that can be utilised for in-situ impact detection. By using this method on several spacecraft in different orbits the detection area can be increased significantly and allow the detection of SD and MM objects with diameters as low as 100 μm. The design of the detector is based on damage equations from HST and EURECA solar panels. An extensive investigation of those panels was performed by ESA and is summarized within this paper. Furthermore, an estimate of the expected sensitivity of the patented detector concept as well as examples for its implementation into large and small spacecraft are presented.  相似文献   

17.
航天器太阳翼展开可靠性的评估方法   总被引:2,自引:0,他引:2  
作为航天器的电能供给装置,太阳翼对于航天器飞行的成功起着重要作用.文章基于航天器太阳翼展开过程的分析,确定了以太阳翼铰链的总驱动力矩作为展开可靠性的特征量.基于“应力—强度”干涉理论,提出了利用太阳翼铰链线驱动力矩和阻力矩等测试数据进行太阳翼展开可靠性定量评估的方法,并给出了某卫星星座用太阳翼展开可靠性评估的应用示例,为航天器太阳翼的可靠性验证提供了技术途径.  相似文献   

18.
    
The main properties of 11622 coronal mass ejections (CMEs) observed by the Solar and Heliospheric Observatory (SOHO) mission’s Large Angle and Spectrometric Coronagraph (LASCO-C2) from January 1996 through December 2006 are considered. Moreover, the extended database of solar proton enhancements (SPEs) with proton flux >0.1 pfu at energy >10 MeV measured at the Earth’s orbit is also studied. A comparison of these databases gives new results concerning the sources and acceleration mechanisms of solar energetic particles. Specifically, coronal mass ejections with width >180° (wide) and linear speed >800 km/s (fast) seem they have the best correlation with solar proton enhancements. The study of some specific solar parameters, such as soft X-ray flares, sunspot numbers, solar flare index etc. has showed that the soft X-ray flares with importance >M5 may provide a reasonable proxy index for the SPE production rate. From this work, it is outlined that the good relation of the fast and wide coronal mass ejections to proton enhancements seems to lead to a similar conclusion. In spite of the fact that in the case of CMEs the statistics cover only the last solar cycle, while the measurements of SXR flares are extended over three solar cycles, it is obvious for the studied period that the coronal mass ejections can also provide a good index for the solar proton production.  相似文献   

19.
We present here a study of Solar Energetic Particle Events (SEPs) associated with solar flares during 2010–2014 in solar cycle 24. We have selected the flare events (≥GOES M-class), which produced SEPs. The SEPs are classified into three categories i.e. weak (proton intensity?≤?1?pfu), minor (1?pfu?<?proton intensity?<?10?pfu) and major (proton intensity?≥?10?pfu). We used the GOES data for the SEP events which have intensity greater than one pfu and SOHO/ERNE data for the SEP event less than one pfu intensity. In addition to the flare and SEP properties, we have also discussed different properties of associated CMEs.  相似文献   

20.
The Russian microsatellite “Universitetskiy-Tatiana” was launched on Jan. 20, 2005 and was both a scientific and educational mission. Its two main aims were declared as: (1) monitoring of the energetic particles dynamics in the near-Earth space environment after solar events and during quiet times, (2) educational activities based on experimental data obtained from the spacecraft. In this paper observations acquired during Dec. 5–16, 2006, known as “Solar Extreme Events 2006”, were analyzed. The “Universitetskiy-Tatiana” microsatellite orbit permits one to measure both solar energetic particle dynamics, variations of the boundary of solar particle penetration, as well as relativistic and sub-relativistic electrons of the Earth’s outer radiation belt during and after magnetic storms. Both relativistic electrons of the Earth’s outer radiation and solar energetic particles are an important source of radiation damage in near-Earth space. Therefore, the presented experimental results demonstrate the successful application of a small educational spacecraft both for scientific and educational programs.  相似文献   

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