The constellation is determined by the date of the solar calendar. The date of the sixth day of the first lunar month in 84 is February 7, and the constellation of that day is Aquarius.
Lunar calendar:1the sixth day of the first month of 984.
Main branch: Jia Zi Bing Wei
Gregorian calendar: Tuesday, February 7, 1984 Aquarius.
Source: Hua Wang.