Comet
彗星
Chinese records of comets dated back to a lon,g tim,e ago . During the Spring and Autumn Period, some 2,200 years ago, Chinese documents already had records of comets, among which the most verifiable one is the record of a comet, which appeared in 613 BC, iri Sprin,g an,d Autumn, Annals . It iS recog-nized as the earliest mention of Halley's Comet in the world, 670 years earlier than the Western Europe, where the earliest record of Halley's Comet was in AD 66.
国古代关于彗星的纪事很早。早在2200多年前春秋时期的古文献中已有关于彗星的记录。最可靠的是《春秋》对出现于公元前613年的彗星记录。这是世界上关于哈雷彗星的最早记录。西欧对哈雷彗星的最早记载是公元66年，这比中国最早的记载晚了670余年。
Since Halley's Comet visits the earth once every 76 years, it came back to the earth 29 times during a period of 2,149 years from 240 BC ( the 7th year of the reign of the First Emper-or of Qin) to 1910 ( the 2nd year of the reign of Emperor Xuantong of Qing). Each of these vis-its was clearly recorded by Chinese scholars.J. R. Hind, a British astronomer, once usedthese continuous data to calculate the orbit of Halley's Comet, and discovered that the angle of the orbit showed a narrowing trend. In the Han Dynasty, it was 170 degrees, but it nar-rowed down t0 161 degrees in the mid-9th century.
哈雷彗星大约每隔76年出现一次，从公元前240年到公元1910年的2149年期间，史书对哈雷彗星出现的记载多达29次，且记述详尽。英国天文学家J．R．海德曾经使用这些数据计算哈雷彗星的运行轨道，他发现，彗星运行轨道角度呈变小趋势：在汉代，角度为1700，到19世纪中叶，则减至1610。
From 1600 BC to AD 1600, China recorded comets 581 times, leaving behind valuable materials. In 635 BC, Chinese astronomers pointed out that the comet al-ways traveled with its back to the sun. Without these repeated observations, the detailed descriptions of the comet tails could not have been made, nor could the relationship between the sun and comets have'been correctly deduced.
从公元前1600年到公元1600年，中国古代对彗星的记载多达581次，留下了极为珍贵的资料。公元前635年，中国古代天文学家指出，彗星总是背对太阳运行。没有上述有关彗星的反复观察，关于彗尾的描述则不可能详尽，也不可能对太阳和彗星之间的关系做出正确的分析。