Description
The Da Ming Jiajing san nian datong li (Imperial calendar, or great universal system of calculating astronomy) is based upon the system of calendrical astronomy developed by the astronomer Guo Shoujin during the Yuan Dynasty (1279-1368). It was officially adapted by the Ming Bureau of Astronomy in 1384. It specified the phases of the moon and contained predictions of when lunar and solar eclipses would occur. The great Chinese navigator Zheng He used Guo Shoujing's methods to determine latitude and longitude on his voyages to the Pacific and Indian ...