《戊寅元历》的日月食推算方法

The Calculation Method of Solar Elipse and Lunar Eclipse in Wuyinyuanli

分析《戊寅元历》的日食和月食推步算法,对记载在《旧唐书》中《戊寅元历》的推算交食的常数和术文进行完整的解读和释证;阐释有关日月食计算常数的天文意义;利用文献分析的方法对《戊寅元历》合朔时距交分、日月食食甚加时、日月食食分和亏初复末等算法的推步思路进行全面梳理;给出《戊寅元历》完整的交食推算过程。

This paper analyzes the algorithm of solar and lunar eclipse in Wuyinyuanli.Constant and text for calculating eclipse of the Wuyinyuanli recorded in Book of Tang have been interpreted completely.The astronomical significance of the constants for calculating eclipse is explained clearly.The thinking of algorithms about the distance of the moon from the node,the middle of the eclipse,magnitude of eclipse and the beginning and end of the eclipse have been combed detailly using the method of literature analysis.This paper gives a complete process of the eclipse calculation of Wuyinyuanli.