Since 1970, he has been engaged in scientific research in astrometry and paleoastronomy. Based on the astronomical calendar data in handed down documents and unearthed documents, this paper studies the restoration of calendars in the early Qin and Han dynasties (Yin Shang, Western Zhou Dynasty, Spring and Autumn Period, Warring States Period, etc.). ) and the missing historical records. This paper systematically sorts out and studies the calendars of the Han Dynasty and subsequent dynasties, such as the stepping methods and accuracy of the calendars of Three Links, Four Points, Linde, Dayan Calendar, Xuanming Calendar and Beginning Calendar. 1992- 1995 presided over the writing and completion of the monograph "Ancient Calendar of China" (cooperation).
In the 1990s, according to the astronomical calendar in ancient documents, the ages of ancient books such as Guoyu, Zuozhuan and Zhushu Chronology were investigated by astronomical methods. It is considered that the astronomical records and chronology framework of Zhong Kang solar eclipse in the current edition and bamboo slips are from the early Tang Dynasty. From 1994 to 1996, the data of solar eclipse and total solar eclipse from pre-Qin to Tang Dynasty were collected and sorted out, and the changes of the early earth rotation speed were analyzed and studied. According to the observation and calculation of 45 solar eclipses in China, the average value of the earth's rotation acceleration parameter C is 3 1.6s/ century 2 (average epoch AD430). Stephenson and Morrison's average C (average duration of 390 BC) was 32.5 seconds/century 2 based on the observation of about 40 eclipses in Babylon (700 BC ~ 50 BC). The results of the two groups are relatively consistent. Therefore, it can be concluded that the C value used in the calculation of the chronicle of solar eclipse in the pre-Qin period should be greater than 3 1s/ century 2.
1996 participated in the research work of Xia, Shang and Zhou dating engineering. In cooperation with ancient philologists, according to the textual research of ancient philologists and the new classification and staging results of Oracle Bone Inscriptions in Yin Ruins and its discharge order, it is concluded that the five-day solar eclipse of Oracle Bone Inscriptions recorded by Bin Group is the only result of the solar eclipse in BC1201~11year. Furthermore, the ruling scope of Wuding and Zu Geng was determined, which laid the foundation for the establishment of the chronological framework of Xia, Shang and Zhou Dynasties. On the basis of ancient philologists' research on Zhou Sacrifice, combined with historical records, it is concluded that the year of Yin's death is about104×-100× BC. Compared with the acceptable age range obtained by archaeological dating scholars later (BC 1049 ~ 1009 and BC 1048 ~ 1008, BC 1008 and BC 1060 ~ 995), AMS was used. The median values of the results are all about 1027 BC, which is similar to the early years of the Western Zhou Dynasty in the ancient edition of Annals of Bamboo Records. This may be the result that dating projects can stand the test of time.
In China's literature, the chronology of three generations can be summarized into two theories: high annual value and low annual value. According to the probability statistical analysis of more than 700 emperors and monarchs in past dynasties, it is likely that the theory of low annual value is more credible. In order to study the historical age, he completed the astronomical chronology monograph "Astronomical phenomena and moon phases in Xia, Shang and Zhou dynasties" (cooperation) from 2000 to 2002.