Event #17: Comet like a celestial magnolia tree observed in China; possibly Halley's

The only ancient text reporting this object is the Han shu (100). It says the Chinese saw a “celestial magnolia tree…in the southwest in the evening” on -161 February 6.¹ The date and location imply a probable UT of February 6.5.

Wen Shion Tsu (1934) and Yu-Che Chang (1979) both suggested the actual year of the observation was -162, and that this was a previous appearance of 1P/Halley. Chang gave the perihelion date as -162 January 20. In reality, Chang did not consider the effects of nongravitational forces and his orbit was probably not very close to the truth. The computations of other astronomers who have included nongravitational forces indicate a perihelion date sometime during -163 October or November.

Full moon: February 18

162 BC, February, China, a thien-chhan comet, or celestial magnolia tree, appeared in the southwest. (Ho, 25)

2nd year of the Houyuan reign period of Emperor Wen of the Han Dynasty; 1st month, day renyin [39]; in the evening a “heavenly tree” (i.e., comet) appeared in the southwest.