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本文提供了八○年二月十六日在昆明观测到的太阳色球层的日全食掩食过程。文中给出太阳可见面上各活动对象(包括黑子、谱斑、暗条、日珥等)的月掩时间,它们是射电观测、电离层观测以及日全食各项光学观测资料分析研究的重要依据。 相似文献
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组织“杭高天文社日全食远征队”赴西部观测日全食,已经给N届的杭高天文社队员带来期盼和激动。从杭州去西部观测日全食,行程非常遥远,往返7000多千米。为选择一个合适的观测卖点,天文社的队员早早就开始在地图上搜索,试图寻找合适的观测点。这次的日全食时间比较短,我们希望选择尽量往西,尽可能接近日全食中心线的地方。除此之外,那里人烟稀少,沙漠戈壁广布,交通和是否有居民点就是十分重要的事了。 相似文献
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中国天文学会普委会组队赴泰国观测日全食日全食是罕见的天文观象，有机会目睹这一现象的发生，无论从天文观测的角度还是进行科普教育是非常有意义的。同时使广大青少年学生直接参与天文科技项目，使他们了解自然认识宇宙掌握更多的天文知识与技能是培养他们学科学爱科学... 相似文献
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1997年3月9日的日全食是本世纪中国可见的最后一次日全食．对这次日食概况和中国、特别是漠河地区见食的情况作一介绍．这次观测结果基本上与预报一致,文中所列各表供观测者处理资料时参考． 相似文献
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Solar System Research - Finding and studying possible collisions of asteroids approaching the Earth requires a significant amount of computation. This paper describes the R0 program created to... 相似文献
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In the text-books of astronomy, sections generally related to the Moon deal with the orbital elements of the Earth-Moon system such asa, e, i, ,
and the time of perigee passage. While the MEAN of the first of the three elements do not vary, mean longitude of the ascending node-mean longitude of the lunar perigee and the time of perigee passage undergoes secular as well as periodic changes due predominantly to the action of the Sun's gravitational attraction. While to a certain degree, explanations related to the calculation of the lunar orbit parameters are given, not a single graphical representation of these short- or long-periodic changes are presented. We allow the number of data related to these periodic changes must cover a large span of time; and if regression of the line of nodes or advances of the line of apses are to be graphically seen, data covering 18.61 and 8.85 yr, respectively, are needed. In this work we particularly aim at the graphical representation of the periodic changes of the line of nodes. 相似文献
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Magnetars are the neutron stars with the highest magnetic fields up to 1015–1016 G. It has been proposed that they are also responsible for a variety of extra-galactic phenomena, ranging from giant flares in nearby galaxies to fast radio bursts. Utilizing a relativistic mean field model and a variable magnetic field configuration, we investigate the effects of strong magnetic fields on the equation of state and anisotropy of pressure of magnetars. It is found that the mass and radius of low-mass magnetars are weakly enhanced under the action of the strong magnetic field, and the anisotropy of pressure can be ignored. Unlike other previous investigations, the magnetic field is unable to violate the mass limit of the neutron stars. 相似文献
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P. Maltby 《Solar physics》1972,26(1):76-82
Observations of the penumbral intensity of sunspots in 13 wavelength regions are presented. In 4 wavelength regions 54 sunspots are measured. In the other wavelength regions the number of sunspots considered ranges from 3–19.The penumbral intensity alters with position within the spot. This intensity variation is found to be comparable with the change in intensity from one spot to another. The penumbral intensity is found to be independent of spot size in the sample considered.The penumbra model of Kjeldseth Moe and Maltby (1969) with = 0.055 is supported by the measurements. 相似文献
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Many asteroids with a semimajor axis close to that of Mars have been discovered in the last several years. Potentially some of these could be in 1:1 resonance with Mars, much as are the classic Trojan asteroids with Jupiter, and its lesser-known horseshoe companions with Earth. In the 1990s, two Trojan companions of Mars, 5261 Eureka and 1998 VF31, were discovered, librating about the L5 Lagrange point, 60° behind Mars in its orbit. Although several other potential Mars Trojans have been identified, our orbital calculations show only one other known asteroid, 1999 UJ7, to be a Trojan, associated with the L4 Lagrange point, 60° ahead of Mars in its orbit. We further find that asteroid 36017 (1999 ND43) is a horseshoe librator, alternating with periods of Trojan motion. This asteroid makes repeated close approaches to Earth and has a chaotic orbit whose behavior can be confidently predicted for less than 3000 years. We identify two objects, 2001 HW15 and 2000 TG2, within the resonant region capable of undergoing what we designate “circulation transition”, in which objects can pass between circulation outside the orbit of Mars and circulation inside it, or vice versa. The eccentricity of the orbit of Mars appears to play an important role in circulation transition and in horseshoe motion. Based on the orbits and on spectroscopic data, the Trojan asteroids of Mars may be primordial bodies, while some co-orbital bodies may be in a temporary state of motion. 相似文献