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1.
A procedure has been proposed for calculating limited orbits around the L2 libration points of the Sun–Earth system. The motion of a spacecraft in the vicinity of the libration point has been considered a superposition of three components, i.e., decreasing (stable), increasing (unstable), and limited. The proposed procedure makes it possible to correct the state vector of the spacecraft so as to neutralize the unstable component of the motion. Using this procedure, the calculation of orbits around various types of libration points has been carried out and the dependence on the orbit type on the initial conditions has been studied.  相似文献   

2.
Depleted narrow (localized in longitude) regions (field tubes) in the plasmasphere, recently discovered in He+ radiation measurements on the IMAGE spacecraft, were first directly observed by the Magion-5 satellite. The low-density regions (notches) occupy <~ 10–30° in longitude and extend from L ~ 2–3 to the plasmasphere boundary in neighboring plasmasphere regions with larger densities. The Magion-5 data give evidence that in the low-density regions temperature is enhanced as compared to the neighboring denser plasmasphere regions. Formation of notches in the plasmasphere is, apparently, associated with AE intensification during weak magnetic storms, while strong magnetic storms usually result in the overall reduction of plasmasphere dimensions. However, even a strong magnetic storm on April 6–7, 2000 (max K p = 9-and min D st ~ ?290 nT), but accompanied by an isolated AE impulse, resulted in a density decrease only in the longitudinally limited post-midnight sector of the plasmasphere.  相似文献   

3.
The results of reconstruction of rotational motion of the Foton M-3 satellite during its uncontrolled flight in September 2007 are presented. The reconstruction was performed by processing the data of onboard measurements of the Earth’s magnetic field obtained by the DIMAC instruments. The measurements were carried out continuously throughout the flight, but the processing technique dealt with the data portions covering time intervals of a few orbital revolutions. The data obtained on each such interval were processed jointly by the least squares method with using integration of the equations of satellite motion relative to its center of mass. When processing, the initial conditions of motion and the used mathematical model’s parameters were estimated. The results of processing 16 data sets gave us complete information about the satellite motion. This motion, which began at a low angular velocity, had gradually accelerated and in five days became close to the regular Euler precession of an axisymmetric solid body. At the end of uncontrolled flight the angular velocity of the satellite relative to its lengthwise axis was 0.5 deg/s; the angular velocity projection onto the plane perpendicular to this axis had a magnitude of about 0.18 deg/s.  相似文献   

4.
The results of updating the parameters of motion of the Spektr-R spacecraft at the end of 2016 have shown that, in January 2018, with a probability close to unity, the condition that a spacecraft stay in the Earth’s shadow is violated; however, in May of the same year, the ballistic life of the spacecraft will be terminated. Thus, in 2017, the question arose of how to design the correction of flight of this spacecraft using its onboard propulsion system. The correction was designed with allowance for the fact that, for the first time since it was launched, the spacecraft in the course of several years, beginning with 2017, repeatedly approaches the Moon, deeply immersing into its sphere of influence. This paper presents the technologically and organizationally convenient, allowable versions of upcoming correction of the Spektr-R spacecraft trajectory and justifies the particular scheme of its implementation.  相似文献   

5.
For a reliable prediction of dose loads on a crew and its habitation environment, which, so far, cannot be calculated with sufficient accuracy, an experimental study of the dynamics of radiation situation characteristics in the modules of the manned International Space Station (ISS) is carried out. The results of prompt monitoring and individual dose control of the crews of seven basic missions in the period of flight from August 1, 2000, to October 28, 2003, are presented. This period of time coincided with the maximum phase of solar activity. On the basis of comparing the measurement data, it was shown that the value of an accumulated individual absorbed dose did not exceed the limits of readings of a two-channel standard R-16 radiometer. The power of the radiation dose absorbed by crew members lies within the range 0.017–0.02 cGy/day and mainly depends on the solar activity level.  相似文献   

6.
The results of numerical simulation of the general circulation in the Titan’s atmosphere at heights from 0 to 250 km are presented, obtained using a new model based on numerical solution of complete equations of motion of viscous compressible gas at the temperature distribution given by an empirical model. The model uses no hydrostatic equation and, as compared with traditional models, has higher resolution in vertical and over horizon. The results presented differ from results of other models and agree with the vertical profile of the zonal component of wind velocity measured by the Huygens spacecraft. Interpretation of this profile is given, including its main peculiarity consisting in a nonmonotonic behavior at heights from 60 to 75 km.  相似文献   

7.
8.
The program of physical studies on the Vernov satellite launched on July 8, 2014 into a polar (640 × 830 km) solar-synchronous orbit with an inclination of 98.4° is presented. We described the complex of scientific equipment on this satellite in detail, including multidirectional gamma-ray detectors, electron spectrometers, red and ultra-violet detectors, and wave probes. The experiment on the Vernov satellite is mainly aimed at a comprehensive study of the processes of generation of transient phenomena in the optical and gamma-ray ranges in the Earth’s atmosphere (such as high-altitude breakdown on runaway relativistic electrons), the study of the action on the atmosphere of electrons precipitated from the radiation belts, and low- and high-frequency electromagnetic waves of both space and atmospheric origin.  相似文献   

9.
The variations in the spatial structure and time in electron fluxes with E = 235–300 keV in the slot region (2 < L < 3) between the radiation belts in the period of November 1, 2014 through December 8, 2014 during weak and moderate geomagnetic disturbances (Kp < 4, Dst >–60 nT) are analyzed based on the data of the RELEC complex on board the Vernov satellite (the height and inclination of the orbit are from 640 to 830 km and 98.4°, respectively). Irregular increases in the fluxes of such electrons and formation of a local maximum at L ~ 2.2–3.0 were observed. It has been shown that the intensity of this maximum is inversely proportional to the L value and grows with an increase in the geomagnetic activity level. New features discovered for the first time in the dynamics of radiation belt electrons manifest in the variations in the local structure and dynamics of fluxes of subrelativistic electrons in the slot region.  相似文献   

10.
11.
The results of measurements of fluxes and spectra carried out using the RELEC (relativistic electrons) equipment onboard the VERNOV satellite in the second half of 2014 are presented. The VERNOV satellite was launched on July 8, 2014 in a sun-synchronous orbit with an altitude from 640 to 830 km and an inclination of 98.4°. Scientific information from the satellite was first received on July 20, 2014. The comparative analysis of electron fluxes using data from RELEC and using experimental data on the electron detection by satellites Elektro-L (positioned at a geostationary orbit) and Meteor-M no. 2 (positioned at a circular polar orbit at an altitude of about 800 km as the VERNOV satellite) will make it possible to study the spatial distribution pattern of energetic electrons in near-Earth space in more detail.  相似文献   

12.
Using data from a radio occultation experiment onboard the Mars Global Surveyor spacecraft, altitude variations of the scale height of the neutral atmosphere in the northern and southern hemispheres of Mars are analyzed. The averaged altitude gradient of temperature for neutrals in the thermosphere is estimated. The revealed variations of the scale height of the neutral atmosphere at zenith angles of less than 82° indicate that the near polar atmosphere is not isothermal at altitudes of 125–145 km, which experimentally confirms predictions of models of the Martian atmosphere. It is shown that when one approaches the terminator the near polar atmosphere is cooled and the effects of variation of the solar zenith angle modulate the local time effects in both hemispheres.  相似文献   

13.
Using the global commons for “peaceful purposes” is agreed upon among states in principle but disputed in substance. While non-militarization has been superceded by the doctrine of non-aggression, the latter, as a necessary rather than sufficient condition for “peaceful purposes”, is tested to its limit by the pressing issue of space weaponization. An international treaty to plug the gaps of the Outer Space Treaty should be negotiated. This would require the prohibition of both weapons in outer space and anti-satellite weapons on Earth. The Draft Treaty on Prevention of the Placement of Weapons in Outer Space and of the Threat or Use of Force against Outer Space Objects, proposed by Russia and China at the Conference on Disarmament, is an effort in this direction. However, divided views are held on several issues arising from the draft treaty, e.g. the efficiency of the current regime of outer space law, definitions of “weapons in space” and “threat or use of force”, and verification. A primary reason for US opposition to the draft treaty are security concerns over its space assets. However, exercising the right of self-defense is excluded from the obligations of disarmament and this is explicitly affirmed in the draft treaty.  相似文献   

14.
《证券法》的颁布与实施,为规范证券市场,使证券市场走向公开、公平和公正,减少股市运作的制度和行为风险,为保障投资者的合法权益,提供了法律保障。各国证券法为了保护投资者的投资热情,以保证证券市场的活跃,大都规定了维护市场“三公”,即公开、公正、公平的原则。他们的证券法律法规规定了有关民事责任的赔偿制度,如美国1934年的《证券交易法》中规定了操纵价格、短线交易、虚假陈述等的民事赔偿责任。因此,应该建立完善证券市场中的民事法律责任制度,在制定后续相应的证券法规和司法解释特别是在制定《证券法》实施细则应该规定具体的、具有可操作性的证券违约责任和侵权责任,补充和完善《证券法》规定的不足和欠缺。  相似文献   

15.
1 引言 新的世纪、新的一年来临,也迎来了第十个五年计划的开始。回顾“九五”航天事业取得的巨大成就,就五院来看,“九五”期间所有的发射型号都取得了成功,尤其是“神舟一号”试验飞船发射及返回成功,使我国跻身于世界载人航天竞争序列,也极大地鼓舞了中华民族的自信心  相似文献   

16.
《载人航天信息》2009,(3):82-87
早期经历:1980年赫尔姆斯毕业于美国空军学院,被任命为军官并被分配到佛罗里达州的埃格林空军基地,担任空军装备实验室的一名F-16武器分离工程师。她成为F-15武器分离的首席工程师。1984年她被选送研究生院。1985年她获得斯坦福大学的学位并被派到美国空军学院担任航空学助理教授。  相似文献   

17.
《载人航天信息》2009,(3):146-150
早期经历:1986年~1991年期间,马格努斯供职于麦道飞机公司,担任保密项目工程师,从事雷达信号衰减技术有效性的内部研发。她还被派参加美国海军A-12强击机计划,主要从事推进系统的研究,直到该计划被取消。  相似文献   

18.
《载人航天信息》2009,(3):131-134
早期经历:1982年毕业后,卡万迪供职于乔普林市伊格尔-皮彻产业公司,任工程师,负责开发国防用途的新型电池。1984年在波音航空航天公司动力系统技术部任工程师。她在波音公司的10年期间,通过动力分析、贸易研究、测定大小、选择、研制、试验和数据分析她支持了许多计划、提案和能量储备系统区的红队。  相似文献   

19.
《载人航天信息》2009,(3):66-69
早期经历:1981年~1985年在美国航空航天局艾姆斯研究中心理论研究分部工作,从事天体物理学研究。  相似文献   

20.
《载人航天信息》2009,(3):10-13
早期经历:10岁开始打网球,成为一名优秀的网球高手,她赢得西湖女校提供的网球奖学金。1968年高中毕业后,她考入位于宾夕法尼亚州的斯沃斯莫尔学院,但弃学寻求当一名职业网球选手,经过三个月的艰苦训练,她认识到自己还不具备当一名成功职业网球手的实力,决定放弃当职业网球手的梦想继续求学,此后她进入美国斯坦福大学。  相似文献   

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