Constellations are determined by the date of the solar calendar. 1July, 997, the Gregorian calendar date is1August, 5, and the constellation of that day is Leo.
Lunar calendar: July 13th, the year of Ding Chou.
Dry branch: Ding Chou Wu Shen Chou.
Gregorian calendar:1August, 997/kloc-Friday, 0/5 Leo
Source: Hua.com.