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Records of solar eclipse observations in ancient China

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1639-1645页

作者： han yanben QIAO QiYuan National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

Like ancient people at other places of the world, the ancient Chinese lived in awe of the Sun. As they felt solar eclipses extremely significant events, they closely observed the occurrence of solar eclipse. Ancient astronomers further realized very early that solar eclipses were one of the important astronomical phenomena to revise and improve the ancient calendar. Interestingly, ancient emperors regarded solar eclipses as warnings from heaven that might affect the stability of their throne. Consequently, observing and recording solar eclipses became official, which dated far back to ancient China when numerous relevant descriptions were recorded in historical books. These records contribute substantially to China as an ancient civilization, as well as to the research of the long-term variation of the rotation rate of the Earth during >2000 years before the 17th century. This paper briefly reviews the perception, observations and recording of solar eclipses by ancient Chinese astronomers.

关键词： solar eclipse ancient record ancient China Earth rotation

The possible influence of solar activity on Indian summer monsoon rainfall

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Applied Geophysics 2007年第3期4卷 231-237页

作者： Ma Lihua han yanben Yin Zhiqiang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

印度夏天季风降雨(ISMR ) 在南亚的气候系统起一个重要作用。最近，关于 ISMR 变化的研究一直在走进更多的深度。在这份现在的报纸，我们主要使用 Scargle periodogram 和小浪变换方法学习在 1871 和 2004 之间的 ISMR 变化的频率并且... 详细信息

印度夏天季风降雨(ISMR ) 在南亚的气候系统起一个重要作用。最近，关于 ISMR 变化的研究一直在走进更多的深度。在这份现在的报纸，我们主要使用 Scargle periodogram 和小浪变换方法学习在 1871 和 2004 之间的 ISMR 变化的频率并且在降雨上考察太阳的活动的可能的影响。分析结果证明复杂 ISMR 变化与显著时间变量特征有频率。调查在降雨和太阳的变化之间的一个可能的连接，我们相信那项太阳的活动影响 ISMR 变化到某程度。

关键词：印度太阳活动夏季季风降雨量

Seasonal and inter-annual variations of length of day and polar motion observed by SLR in 1993―2006

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Chinese Science Bulletin 2009年第1期54卷 46-52页

作者： GUO JinYun han yanben National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China College of Geodesy and Geomatics Shandong University of Science and Technology Qingdao 266510 China

A time series of length of the day (LOD) and polar motion (PM) were estimated from the range data measured by the satellite laser ranging technique (SLR) to LAGEOS 1/2 through 1993 to 2006. Com-pared with EOPC04 released by the International Earth Rotation and Reference Systems Service (IERS),the root mean squares errors for LOD,X and Y of PM are 0.0067 milliseconds (ms),0.18 milli-arc-sec-onds (mas) and 0.20 mas,respectively. Then the time series are analyzed with the wavelet transforma-tion and least squares method. Wavelet analysis shows that there are the obvious seasonal and inter-annual variations of LOD and PM,but the annual variation cannot be distinguished from the Chandler variation because these two frequencies are very close. The trends and periodic variations of LOD and PM are given in the least squares sense. LOD changes with the annual and semiannual periods. The annual and Chandler variations for PM are also detected,but the semiannual motion for PM is not found. The trend rate of the LOD change in 1993―2006 is ?0.18 ms per year,and the difference from the well-known 1.7 ms per century showed that the trend rate is diverse in different periods possibly. The trend rates of PM in the X and Y directions are 2.25 and 1.67 mas per year respectively,and the North Pole moves to 36.5°E relative to the crust,which is different from the direction of Greenland.

关键词：卫星激光距离修正白昼长度极地运动地球转动

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Editor’s note

Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 321-322页

作者： yanben han HuLi Shi

With development and progress of human society, the satellite navigation and positioning technology is playing a more important role in human life. At present, the most successful positioning system is the Global Posi... 详细信息

关键词： s note Editor IGSO

Revisit of short-term periodicities in solar mean magnetic field

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Chinese Science Bulletin 2014年第33期59卷 4478-4483页

作者： Zhiqiang Yin Jie Chen yanben han National Astronomical Observatories Chinese Academy of Sciences

Short-term variations of the solar mean magnetic field(SMMF) were investigated through re-analyzing the data from the Wilcox Solar Observatory during the last four solar activity cycles using continuous wavelet *** demonstrated the time-variable characters of short-term periods of SMMF. Our results indicate that the SMMF has main periods of about 27 and 13.5 days not only in the minimum and maximum years of each activity cycle, but also in the increase and decrease of the solar cycle. The result is partly different from the conclusion that the SMMF has dominant period of about 27 days during the solar maxima and about 13.5 days during the solar minimum years(Ye et al. in Solar Phys 279:411–418, 2012). The entire time span of SMMF was investigated and discussed further.

关键词：太阳平均磁场周期性短期太阳活动周期连续小波变换太阳物理学时间变化时间跨度

Inter-annual variation of the earth rotation and El Nio

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Chinese Science Bulletin 2002年第2期47卷 105-107页

作者： han yanben ZHAO Juan LI Zhian National Astronomical Observatory Chinese Academy of SciencesBeijing 100012China Department of Astronomy Beijing Normal UniversityBeijing 100875China

The relationship between the inter-annual variations of the earth rotation, atmospheric angular momentum (AAM), sunspot number and El Ni(?)o is analyzed. The result shows that the inter-annual variation of the earth rotation responds to the variation of AAM and the preg-nancy of El Ni(?)o timely. Generally, the inter-annual compo-nent of the earth rotation will reach zero in a changing proc-ess that increases from the negative to the positive extreme before El Ni(?)o occurs about half year or more. And the solar activity may have certain influence on the appearance of El Ni(?)o. We consider that El Ni(?)o will possibly appear around the end of 2001.

关键词： El Nino inter-annual variation of earth rotation atmospheric angular moment solar activity.

Selection of satellite constellation framework of CAPS

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Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 458-471页

作者： han yanben MA LiHua QIAO QiYuan YIN ZhiQiang AI GuoXiang National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

Based on the idea of transmitting the satellite navigation and positioning system, taking the distribution and variation of the Position Dilution of Precision factor (PDOP), which is closely related with the precision of navigation and positioning, within the China area as the primary criterion, we analyze and discuss the tentative plan of constellation configuration consisting of geosynchronous orbit (GEO) communication satellites and inclined geosynchronous orbit (IGSO) satellites for the transmitting Chinese Area Positioning System (CAPS). We emphatically consider the effect on the PDOP by the three major orbit parameters including the inclination, eccentricity and right ascension of the ascend- ing node (RAAN) of IGSO satellites, to research the strategies of the constellation configuration of CAPS through software emulation. Various constellation configurations are analyzed and compared and the results show that the constellation configuration, consisting of three IGSO communication satellites in three orbits with the same inclination as 50°, the difference in RAAN as 120° and the same "8" shaped ground track centered near 115°E and four or five GEO communication satellites within 60°E to 150°E, can satisfy the requirement that Chinese domain is availably covered and the navigation and positioning with high precision could be obtained. Three relatively excellent constellation configurations are initially suggested and some concerned issues are discussed in this work.

关键词： satellite navigation regional positioning system constellation CAPS

Long-term variations of solar activity

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Chinese Science Bulletin 2007年第20期52卷 2737-2741页

作者： YIN ZhiQiang MA LiHua han yanben han YongGang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Using the Lomb-Scargle periodogram we analyzed two sunspot series: the one over the past 11000 years at the 10-year interval based upon the survey data of 14C concentration in tree-rings, recon- structed by Solanki et al.; and the sunspot number over the past 7000 years, derived from geomagnetic variations by Usoskin et al. We found the periods and quasi-periods in solar activity, such as about 225, 352, 441, 522 and 561 a, and near 1000 and 2000 a. An approach of wavelet transform was applied to check the two sunspot time series, with emphasis on investigating time-varying characteristics in the long-term fluctuations of solar activity. The results show that the lengths and amplitudes of the periods have changed with time, and large variations have taken place during some periods.

关键词：太阳活跃性太阳黑子光谱分析光波传播

Functions of retired GEO communication satellites in improving the PDOP value of CAPS

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Science China(Physics,Mechanics & Astronomy) 2009年第3期52卷 423-433页

作者： han yanben MA LiHua QIAO QiYuan YIN ZhiQiang SHI HuLi AI GuoXiang National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China

This paper briefly introduces the maneuverable feature of the slightly inclined geosynchronous orbit (SIGSO) satellites under a new control model degraded from the geosynchronous orbit (GEO) communication satellites which will retire as most of the fuel in these satellites has been consumed. Basing on the transmitting Chinese Area Positioning System (CAPS), the authors, by analyses, indicate that such satellites can make an improvement to CAPS constellation configuration, especially to the PDOP value from simulation. The results show that the use of SIGSO satellites can (1) actualize three-dimensional (3D) navigation and positioning compared with the situation, which, only using GEO satellites, cannot be carried out, and improve navigation and positioning accuracy to some extent; (2) reuse the communication services of these satellites for more years, and GEO communication satellites will be retired at a later time and delay their time to become space debris and reduce their pollution of the space environment, so that valuable space resources are maximally used. As for the use of these satellites in the transmitting positioning system, the authors present some views and suggestions in this work.

关键词： satellite navigation and positioning GEO communication satellite retired satellite CAPS