授时大统历法五星推步的精度研究

The Study of Precision Positions of Five Planets for Shoushi-Datong Calendar

用元明授时大统历步五星术和现代天文计算方法分别计算大明嘉靖十年(1531)五星每日夜半位置.利用比较法,对两种计算方法得到的五星会合周期、逆行段和合冲(或上下合)角速度进行比较,通过行星平运动和实运动的比较,分析研究授时大统历步五星精度,给出定量分析结果,探讨了授时大统历步五星误差原因.

Shoushi-Datong calendar is a very important ancient Chinese astronomical calendar,it was applied for over 380 years in the Chinese history. It is introduced to calculate principle and method for the positions of five planets by Shoushi-Datong. It is analysed to produce the reasons for actual motion＇s errors of five planets computed by Shoushi-Datong calendar. It is discussed to calculate ＂ying suo cha＂ by Shoushi-Datong calendar and ＂centre difference＂ by modern astronomy. The daily positions of the five planets （1531） are computed by Shoushi-Datong calendar and modern astronomical method respectively. The computational results are studied by comparative analysis of the mean and actual motion of five planets such as synodic period, backward movement and angular velocity of coition or opposition act.The quantitative analysis are given in this paper.