《授时历》交食推步研究

在借鉴《大统历》的基础上，研析并较正了《授时历》“步交食”术文；同时根据《授时历》的平、定朔（望）推步，完整地给出其交食推步步骤和一般方法；用《授时历》推步和现代计算结果对部分交食记录进行了计算分析，通过比较可得出古记录是观测实录还是预报结果，以及其中是否存在人为等因素，指出本文给出的《授时历》交食推步法确是其时天文官所用之法

RESEARCH ON THE CALCULATING METHODS OF ECLIPSES ABOUT THE CALENDAR OF SHOUSHI

The calendar of Shoushi( 1281 AD,Yuan dynasty) is one of the famous,precise ones of China,which was made by Guo shoujing(a well known Chinese ancient astronomer for devising and constructing new astronomical instruments and making nontraditionally new calendar system,Shoushi Calendar ) and his co workers in 13th century.It was kept in use for longer than 300 years.This paper studies and analyses the part of Bu Jiaoshi (calculating methods of eclipses) of this calendar and Datong (another Chinese ancient calendar with almost the same fundamental constants,calculating methods as Shoushi,1304 AD,Ming dynasty).All of the errors,such as due to the omitting,redundancy and so on,have been corrected.This calendar cast off the calculating method of the year after year from the epoch of distant ancient time once for all.According to the calculation of the mean,real new (full) moon of Shoushi,the whole steps of the calculating methods of eclipses about the calendar have been obtained.At the same time,by comparing the methods of Shoushi with those of modern times this paper analyses the calculating results of several old eclipse records and makes a distinction between the records that are the results of real observations or prediction ones or man made ones. The calculating methods of eclipses about the Shoushi Calendar summed up in this paper are the true methods and they also had been uaed by the astronomers at that time.