殷商西周时期中原五城可见的日食

THE VISIBLE SOLAR ECLIPSES AT 5 CITIES IN CENTRAL CHINA FROM YIN-SHANG PERIOD TO THE WESTERN ZHOU DYNASTY

一日食,是一种天文现象,它的发生有一定规律性。整个地球上发生日食的机会远比月食为多,但每次发生月食的时候,半个以上的地球可见,日食却仅限于部分地区。因此就某一确定地点来讲,可见的日食却比月食为少。平均约2.6年可见一次日偏食。至于日全食,大约要经历三个世纪才有可能见到一次。古人不明白这一点,把日食视为不祥之兆,而感到恐惧,认为是上天示警,便禳灾祈福。甚至有的君王还下诏罪己,修明政治。

The Canon of Eclipses, which gives all eclipses from—1207 to 2161, was written by Th. v. Oppolzer and published in 1887. Last year is the centenary of its publication. It has been an important reference for astronomers and historians to study eclipses at all times and in all countries. However, there are some errors in Oppolzer's Canon for ancient eclipses, and the year—1207 is not early enough for studying eclipses in the Yin-Shang period either. A new canon of 8444 solar eclipses for the years-1500 to 2050 is calculated with the new elements of the sun and the moon by the author. According to Hansen's theory the visible circumstances at 13 famous historical cities in China are calcuIated on the basis of the 'new canon of 8444 solar eclipses' . 1730 solar eclipses took place in the years between—1500 and—770. The local circumstances of all the 328 visible solar eclipses at 5 cities (Beijing, Anyang, Luoyang, Jangling, Xian) during the period are published in this paper. It can be regarded as a supplement of Oppolzer's Canon as well as a gift in commemoration of the centenary of its publication.