中国古代日食的宿度记录

统计和分析我国古代日食的宿度记录。有宿度的正史日食记录主要集中在两汉、唐朝、宋朝和清朝。这些宿度记录显然是事先或事后通过计算得到的。明清两代某些地方志追溯了过去朝代发生日食的宿度,但所记当代的宿度却大多是错误的。通过与现代计算结果的比较,发现两汉的宿度记录是按照太阳的平运动来计算的,唐代日食记录对太阳不均匀运动作了改正。通过与古代历法中计算结果的比较,探讨了两汉和唐代日食宿度记录的来源。

Position of the Sun in Ancient Chinese Records of Solar Eclipse

The measurements of solar positions in solar eclipse records in ancient China are analyzed. Such records in official historical documents are mainly found in those of Western Han, Eastern Han, Tang, Song and Qing dynasties. The solar positions in these records were obviously calculated beforehand or afterworlds. Some local chronicles of the Ming and the Qing dynasties traced back the past ones, but most of their real-time records are erroneous. An analysis by modern computation shows that the records of the Han Dynasties were computed according to uniform solar motion, while for those of the Tang Dynasty, an annual correction was added. The origins of records of the Western Han, Eastern Han and Tang dynasties are discussed by comparing with results calculated according to ancient calendars.