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1.
On the basis of an analysis of the data of multi-satellite observations of magnetic clouds at the path Venus-Earth, the dependence of their geoeffectiveness on the orientation in the ecliptic plane and position relative to the Sun-Earth line is determined in the paper. The cloud parameters were determined on the basis of the model of a force-free cylindrical flux rope. The search for magnetic clouds in the flow of data from the monitoring space vehicle was performed using a special-purpose computer program.  相似文献   

2.
Preliminary results of optical observations of midlatitude auroras at the Geophysical observatory of ISTP SD RAS in the south of Eastern Siberia (52°N, 103°E) during two strong magnetic storms on October 29–31, 2003 and November 20–21, 2003 are analyzed. The results of observations are compared to similar data on midlatitude auroras observed at the geophysical observatory in previous years. The recorded maximum intensities of atmospheric emissions and accompanying solar and geophysical conditions make it possible to conclude that the analyzed midlatitude auroras in their optical manifestation can be considered as extreme events observed at midlatitudes.Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 6, 2004, pp. 616–621.Original Russian Text Copyright © 2004 by Mikhalev, Beletsky, Kostyleva, Chernigovskaya.  相似文献   

3.
Based on the Kohonen algorithm, a self-training neural network is constructed which allows one to classify geomagnetic disturbances using the data on parameters of the solar wind and interplanetary magnetic field. Such an approach permits one to consider the suggested classification simultaneously as space and physical, since the space origin of disturbances of different kinds is considered within the framework of the classification. As a result of numerical experiments, we have succeeded in isolating basic classes of complexes of disturbed parameters accounting for various events of the space weather, each of which is responsible for corresponding global magnetospheric conditions.  相似文献   

4.
We present the results of spectral analysis of a signal of oblique sounding of the ionosphere. This signal was received at the Doppler phase-angle measuring facility of Kazan University during the geomagnetic storm on October 29–31, 2003. On various short-wave (SW) radio paths, intense variations of Doppler frequency shift were observed. These variations exceeded variations observed on days without geomagnetic disturbances by an order of magnitude (and by two orders of magnitude during some short periods). Relatively short periods (1–3.5 min) are predominant on these days in variations of the Doppler frequency shift. It should be noted that, while for weak geomagnetic disturbances the response in the form of distortions of SW signal parameters was observed, as a rule, only for the paths coming from high-latitude regions, in the given case the effect was observed for all radio paths.Translated from Kosmicheskie Issledovaniya, Vol. 42, No. 6, 2004, pp. 640–644.Original Russian Text Copyright © 2004 by Bochkarev, Petrova, Teplov.  相似文献   

5.
孙青  许彤 《中国航天》2004,(2):24-28
尽管自2002年以来,商业卫星发射次数呈减少趋势,但2003年世界范围内的航天发射活动连续第三年保持了平稳态势。  相似文献   

6.
《中国航天》2003,(2):3-3
本刊讯 “神舟”4号飞船的发射和返回成功,既为科技集团去年的工作画上了圆满的句号,同时又为今年的科研生产开了个好头。1月16日,科技集团公司召开了型号工作会议。会议的主题是贯彻落实十六大精神,深入学习江泽民同志和中央领导有关航天科技工业的一系列指示精神,总结经验,查找不足,认清形势,明确任务,落实责任,采取措施,确保圆满完成2003年型号任务。  相似文献   

7.
李莉 《中国航天》2001,(5):38-41
战斧,是一个耳熟能详的名字,90年代以来的几场局部战争使其名声大振。自1991年以来,美国海军平均每年要消耗100枚战斧导弹。从海湾战争到科索沃,近千枚战斧从一艘艘美国战舰和潜艇上发射,使得战斧成为美国强权政治的急先锋,也成为对别国实施远距离精确打击的中坚力量。 但近几场局部战争同时也提出了要发展一种造价便宜、全天候作战、精确打击以及可对加固目标进行打击的新型战斧的要求。在这种背景下,战术战斧(TacTom)应运而生。北约空袭南联盟后,美国海军根据战斧巡航导弹的作战使用,开始重新评估未来战斧巡航…  相似文献   

8.
2003年是航天科技集团公司的喜事年。这一年,我们上下同心,夺取了抗击非典的全面胜利;我们划动神舟,在天河中留下了中国航天员的身影;我们铸造神剑,提高了共和国的安全系数……所有这一切,正是集团公司大步流星奔一流的真实写照。  相似文献   

9.
2003年,世界航天不断前进,硕果累累,但也发生了一些令人震惊的灾难。全球共进行了63次航天发射,与2002年相当。载人航天喜忧参半,年初美国“哥伦比亚号”航天飞机的失事给世界航天事业蒙上了一层阴影,但是俄罗斯“联盟号”飞船的多次安全发射与返回,尤其是中国“神舟”5号飞船首次载人航天的成功又带来了新的希望;国际空间站和重复使用航天器的发展均受到一定影响。深空探测又掀热潮,取得了许多新的进展。卫星应用也有所进展,研制和发射了一些新的侦察卫星、军事通信卫星和导航卫星。  相似文献   

10.
This paper examines the possibility of regular orbital corrections for a satellite controlled by an impulsive force applied along the induction vector of the local geomagnetic field. The main purpose of the correcting considered in the paper is to eliminate the drift in secular variation of the relative orbital parameters over the orbital period. The obtained results are applied to the formation flying problem. The developed method is tested using numerical simulation.  相似文献   

11.
We consider in detail the intense Pc5 pulsations of the magnetic field, riometric absorption, and electron fluxes occurred on the recovery phase of the strong magnetic storm on November 21, 2003. The global structure of these disturbances is studied using the world network of magnetometers and riometers supplemented by the data of particle detectors onboard the LANL geosynchronous satellites. The local spatial structure is investigated according to data of the regional network of Finnish vertical riometers and of stations of the IMAGE magnetic network. Though a certain similarity is observed in the frequency composition and time evolution of the variations of magnetic field and riometric absorption, the local spatial structure of these oscillations turns out to be different. It is suggested that these variations can be manifestations of oscillatory properties of two weakly connected systems: the magnetospheric MHD waveguide/resonator and the system cyclotron noise + electrons. The recorded Pc5 oscillations are, presumably, a result of excitation of the magnetospheric waveguide on the morning and evening flanks of the magnetosphere. At high velocities of the solar wind this waveguide can appear in a metastable state. Not only jumps in the solar wind density, but injection of electrons into the magnetosphere as well, can serve as a trigger for the waveguide excitation.  相似文献   

12.
Radio bursts in the frequency range of 100–1500 kHz, recorded in 1997–2000 on the INTERBALL-1 satellite during the solar flares preceding the strong geomagnetic storms with D st < ?100 nT, are analyzed in this paper. The observed long-wave III-type radio bursts of solar origin at frequencies of 1460 and 780 kHz were characterized by large values of the flux S f = 10?15 ?10?17 W/m2 Hz and duration longer than 10 min. The rapid frequency drift of a modulated radio burst continued up to a frequency of 250 kHz, which testified that the exciting agent (a beam of energetic electrons) propagated from the Sun to the Earth. All such flares were characterized by the appearance of halo coronal mass ejections, observed by the LASCO/SOHO, and by the presence of a southward Bz-component of the IMF, measured on the ACE and WIND spacecraft. In addition, shortly after radio bursts, the INTERBALL-1 satellite has recorded the fluxes of energetic electrons with E > 40 keV.  相似文献   

13.
Investigations of the effect of geomagnetic activity factors on the cardiac rhythm regulation and arterial pressure of cosmonauts during the expeditions onboard the Soyuz spacecraft, and the MIR and ISS orbital space stations was carried out for various durations of flight in weightlessness and, under control. Groups of cosmonauts were inspected under flight conditions outside the geomagnetic disturbances and in ground preflight conditions, during disturbances without them. The presence of specific effect of geomagnetic disturbances on the system of vegetative regulation of blood circulation of cosmonauts during the flight was demonstrated for the first time. The response of cosmonauts’ cardiac rhythm on the magnetic storm is definitely revealed; however, it depends on the initial functional background and, in particular, on the state of mechanisms of vegetative regulation (the duration of flight and adaptation to it).  相似文献   

14.
2003年是世界航天运载史上揭开新篇章的一年。中国成功发射神舟5号载人飞船,成为继前苏联和美国之后第三个能够把宇航员送入地球轨道的国家。  相似文献   

15.
《中国航天》2003,(4):14-14
2003年是科工集团公司型号研制生产任务的攻坚年。日前,科工集团公司下发了《关于落实第四次工作会议精神确保型号科研生产任务圆满完成的通知》,明确了2003年型号任务的工作目标是以确保重点型号研制飞行试验和定型飞行试验成  相似文献   

16.
On the basis of data of two networks of Canadian stations and also of extra- and intra-magnetospheric satellites, daytime long-period geomagnetic pulsations related to sudden impulses of the dynamic pressure of the solar wind (SW) are studied. The influence of SW parameters, interplanetary magnetic field (IMF), and geomagnetic activity on the propagation direction, polarization, and amplitude of pulsations is discussed. It is shown that at arrival front of the solar wind inhomogeneity at the place of its tangency, surface oscillations within the range of Pc5 geomagnetic pulsations are excited on the magnetopause, and they run away from the tangency point to the nighttime side with increasing amplitude and opposite polarization. The pulsation properties and the position of the running-away point are explained by the mechanism of their excitation on the magnetopause by the inclined front of the inhomogeneity and also by the Kelvin-Helmholtz instability. Increases in SW density observed ahead of the shock front were able to cause pulsation excitation onsets prior to the sudden storms commencement (SSC) front arrival. The observed increase in geomagnetic activity after SSC could change the direction of pulsation propagation from anti-sunward to sunward. The analysis of oscillation spectra made it possible to assume that pulsations with a frequency of the order of 2.5 mHz are of a global character, they are not related to oscillations in SW and are excited by sharp SSC fronts.  相似文献   

17.
18.
Unique springs, discharging from the surface of an arctic glacier, release H(2)S and deposit native sulfur, gypsum, and calcite. The presence of sulfur in three oxidation states indicates a complex series of redox reactions. Physical and chemical conditions of the spring water and surrounding environment, as well as mineralogical and isotopic signatures, suggest biologically mediated reactions. Cell counts and DNA analyses confirm bacteria are present in the spring system, and a limited number of sequenced isolates suggests that complex communities of bacteria live within the glacial system.  相似文献   

19.
袁越 《中国航天》2000,(10):28-30
由于运行位置的原因,人类发射火星探测器要‘相机行事”。适时发射可以使探测器在飞往火星时既省时,又省力。这样的机会一般每两年多才出现一次。为了加紧探索火星,美国几年前设立了火星勘测者计划,准备每遇一次机会就发射两颗探测器。1996年发射的头两颗探测器——火星探路者和火星全球勘测者(MGS)均顺利抵达目的地。1998年底和1999年初,美又相继发射了火星气候轨道器(MCO)和火星极区着陆器(MP)(统称火星勘测者1998),但这两颗探测器却在最后入轨和着陆的关头相继失踪,引起广人们对美国火星探索计划的强烈批评。在这种情…  相似文献   

20.
Variations in concentration of ions H+, He+, and O+ are studied at a height of about 700 km using the data of continuous observations onboard the DEMETER satellite at the decline and in the minimum of solar activity from 2004 to 2008. Latitudinal distributions, seasonal behavior, and irregular variations in ion concentrations and their dependence on solar and geomagnetic activity are considered. Within this altitude range, for the first time an analysis is performed of the dataset of many-year continuous observations in both hemispheres from the equatorial to subauroral latitudes. This made it possible to describe the seasonal and irregular variations of the concentrations of main ion species with better time and spatial resolution than in the available empirical models. The dependence of concentrations of three types of ions on solar and geomagnetic activity is studied at time scales from several days to several years, and it is shown that the anti-phase change in concentrations of O+ and light ions known from publications is partly a result of mutual dependence of solar and geomagnetic activity and is observed only at time scales beginning from several months. At time scales from several days to several weeks, variations in the concentration of O+ and light ions are governed mainly by solar and geomagnetic activity, respectively.  相似文献   

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