Chinese calendar and mathematical astronomy

Abstract

The Chinese calendar (li) was a system of mathematical astronomy that included mathematical techniques for the computation of celestial movements. It was the basis for producing astronomical ephemerides and annual almanacs. Calendar making started early in China. Since the Great Inception calendar reform in 104 BC, China has produced about 100 calendars (astronomical systems). The focus of calendar making was the prediction of solar, lunar, and planetary motions. As astronomy developed, new observational discoveries were incorporated into the calendar to make the system more precise. The history of astronomy in ancient China was largely a history of calendar making.