从《大统通占》星表重新考察明初的恒星观测---兼论传统星官的变化

《大统通占》是明初钦天监编纂的占书,其中保存了一些明初恒星观测数据.试图以此重新考察明初的恒星观测情况.首先,分析了该书的成书年代,指出其应完成于永乐四年至二十三年之间.然后,以依巴谷星表(2007)为标准,对该书记载恒星数据的赤纬误差进行傅里叶分析,发现这些数据应观测于洪武年间,且其精度达到明末以前星表的最高水平.另外,梳理了明初钦天监观测恒星的条件,认为其观测水平的提高与郭守敬对仪器的改进措施密切相关.最后,对这份精密星表的研究也进一步揭示了古代星官发生的历史变化.

A Re-examination of the Star Observation in Early Ming Dynasty Based on the Star Catalogue of Datong Tongzhan ---with Discussion on the Changes of Traditional Chinese Constellations

Datong Tongzhan is a divination book compiled by the Imperial Board of Astronomy in early Ming dynasty, which preserves some positional data of stars observed at that time. Based on this star catalogue, a further research is carried out on star observation in early Ming dynasty. Firstly, through a deep analysis, it is found that this book should be completed between the 4th and 23rd year of Yongle reign. Then, with Hipparcos star catalogue (2007) as standard, Fourier analysis of the declinational error of these stellar data is carried out, which suggests that these data should be observed in Hongwu reign, and reach the highest level of accuracy before the end of Ming Dynasty. Besides, an investigation of the condition of the Imperial Board of Astronomy in early Ming dynasty demonstrates that the improvement of accuracy was mainly due to the betterment made by Guo Shoujing on observational instruments. Finally, the study on this accurate star catalogue further reveals historical changes of the ancient Chinese constellations.