《授时历》的研究

RESEARCH ON THE SHOU SHI CALENDAR

在对《元史·历志》中“授时历经”的“步气朔”、“步日躔”、“步月离”、“步交会”部分的术文进行进一步解读的基础上，该文对《授时历》进行了下面几个方面的研究：（１）没日、灭日时刻计算公式的构造方法；（２）每日太阳位置计算过程中日差的意义；（３）迟疾差公式构造过程中的缺陷；（４）月亮每日去极度的求法；（５）日食的食限问题和食分的计算步骤；（６）日食实例计算。

Based on the further investigation on the original text of Bu Qi Shuo,Bu Ri Chan,Bu Yue Li,Bu Jiao Hut in Shou Shi Li Jing in Records of Calendar, History of the Yuan Dynasty,this paper researches into the Shou Shi Calendarin the following aspects:(1) Methods of constructing the formulas for calculating the time of mo ri and mie ri;(2) Explanation of ri cha(everyday difference)in the course of calculating everyday position of the sun;(3)Defect in the course of constructing the formula of Chi ji cha (the difference of lag or advance)of the moon;(4) Calculative method for everyday polar distance of the moon;(5)discussion of solar eclipse limit and method of calculating solar eclipse factor;(6) An example of calculating solar eclipse.