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321.
Possible mechanisms of solar-climatic connections, which may be of importance as over short and long time intervals, are discussed. The variations of energetic balance of Earth's climatic system for the last fifty years are estimated. It is ascertained that the disbalance between the flux of solar energy that comes to the Earth and radiates to space is of 0.1% for the last ten years. The suggested mechanism makes it possible to explain not only the observed variation of the enthalpy of the Earth's climatic system for the period 1910-1980, but also the climate anomalies during last thousand years: the climate optimum in 12 century, and"small glacial period" in 16-17 centuries. 相似文献
322.
星上运动部件对气象卫星姿态影响的研究 总被引:3,自引:0,他引:3
以中国下一代静止轨道气象卫星为对象,分析了有效载荷扫描镜运动和太阳翼步进运动对卫星姿态的影响。结果表明,有效载荷的正常扫描运动和太阳翼的步进运动对卫星姿态的影响很小,但有效载荷的黑体校准运动对卫星姿态的影响很大,必须进行补偿控制,否则卫星有效载荷扫描镜的指向精度无法满足设计要求。 相似文献
323.
Satoshi Miura Kazuki Saito Ayako Torisaka Victor Parque Tomoyuki Miyashita 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(9):2706-2715
A shape of the satellite’s solar sail membrane is essential for unloading angular momentum in the three-axis stabilized attitude control system because the three-dimensional solar sail can receive solar radiation pressure from arbitrary directions. In this paper, the objective is the shape optimization of a three-dimensional membrane-structured solar sail using the angular momentum unloading strategy. We modelled and simulated the solar radiation pressure torque, for unloading angular momentum. Using the simulation system, since the unloading angular momentum rate is maximized, the shape of the three-dimensional solar sail was optimized using a Genetic algorithm and Sequential Quadratic Programming. The unloading velocity in the optimized shaped solar sail was greatly improved with respect to a conventional flat or pyramid solar sail. 相似文献
324.
从工程实际出发对工程上常用的聚光器进行性能比较,可以得出适合太阳能火箭发动机(STP)的聚光器及其具有的性能优点。在研究此种聚光器设计方法的过程中,推导出相关公式和其中的关键技术,这对STP聚光器的工程设计具有重要的指导价值。 相似文献
325.
R.D. Bentley A. Csillaghy J. Aboudarham C. Jacquey M.A. Hapgood K. Bocchialini M. Messerotti J. Brooke P. Gallagher P. Fox N. Hurlburt D.A. Roberts L. Sanchez Duarte 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Heliophysics is a new research field that explores the Sun–Solar System Connection; it requires the joint exploitation of solar, heliospheric, magnetospheric and ionospheric observations. 相似文献
326.
Angela Gardini Monica Laurenza Marisa Storini 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Fifteen solar energetic particle (SEP) events have been analyzed using proton flux data recorded by the Helios 1, Helios 2, and IMP 8 spacecraft in the energy range ∼4–40 MeV during 1974–1982. For each of the events at least two of the spacecraft have their nominal magnetic footpoint within 20° in heliocentric longitude from each other. The SEP events are sub-grouped as a function of their heliocentric longitudinal separation and heliocentric radial distance from the SEP associated solar flare and several case studies are presented in this paper. Main results concerning their usage in estimating the SEP radial dependence are given. Moreover, we investigate the behavior of the third not connected spacecraft in order to study the dependence of the proton flux as a function of flare location. It is found that the contribution of the longitudinal gradient in determining variations in the SEP proton flux is particularly relevant for spacecraft having their magnetic connection footpoint separated from the flare between 30° and 50°. 相似文献
327.
D.K. Sharma M.S. Khurana Jagdish Rai 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The data on thermal fluctuations of the topside ionosphere have been measured by Retarding Potential Analyser (RPA) payload aboard the SROSS-C2 satellite over the Indian region for half of the solar cycle (1995–2000). The data on solar flare has been obtained from National Geophysical Data Center (NGDC) Boulder, Colorado (USA) and other solar indices (solar radio flux and sunspot number) were download from NGDC website. The ionospheric electron and ion temperatures show a consistent enhancement during the solar flares. The enhancement in the electron temperature is 28–92% and for ion temperature it is 18–39% compared to the normal day’s average temperature. The enhancement of ionospheric temperatures due to solar flares is correlated with the variation of sunspot and solar radio flux (F10.7cm). All the events studied in the present paper fall in the category of subflare with almost same intensity. The ionospheric electron and ion temperatures enhancement have been compared with the IRI model values. 相似文献
328.
M. Hayosh Z. Nme
ek J. afrnkov G.N. Zastenker 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2005,36(12):2417-2422
The magnetosheath plays a dominant role in the Sun–Earth connection because the magnetosheath field and plasma actually interact with the magnetosphere. The interactions change the magnetospheric magnetic field from its nominal value through a long chain of different processes. The change is usually described by geomagnetic indices and thus it can be expected that these indices would reflect changes in the magnetosheath. The present paper analyzes the relation between geomagnetic activity characterized by changes of the Kp, DST and AE indices and ion flux measured in the night-side magnetosheath. The results suggest a weak dependence of the DST index on the ion flux in the inner magnetosheath that is connected with a magnetopause displacement. On the other hand, fluctuations of the ion flux in the analyzed frequency range do not correlate with any of the indices. 相似文献
329.
本文讨论了从第13—22太阳周太阳和地磁周的特征.运用自激励门限自回归时间序列模型和最大熵谱原理自回归数学方法来模拟和预报地磁aa指数年均值峰值和时间.峰值时间是1993年秋天或1994年春天.地磁aa指数年均值峰值是26—29.第22地磁周是一个中等活动的周. 相似文献
330.
本文讨论了非线性动力Alfven波在1>>β>>me/mi条件下形成孤子解的限制条件,表明只有亚Alfven速度才能形成压缩型孤子.由动力Alfven波孤子和湍流产生的极大纵向电子速度不会超过本底电子热速度,但由此产生的纵向电场在小尺度范围可以很强,这可能对太阳风的能量传输与粒子加速产生一定影响. 相似文献