The great Chinese fireball of December 22, 2020

Abstract

On December 22, 2020, at about 23h 23m 33s UTC a very bright fireball was seen in the sky of southeastern China. The fireball lasted for several seconds and ended with an atmospheric explosion that was detected by US surveillance satellites. According to CNEOS’s data, the fireball moved with a mean speed of 13.6 km/s and exploded at an altitude of about 35.5 km (Lat. 31.9^{circ } N; Long. 96.2^{circ } E). In this paper we estimate the atmospheric trajectory, the heliocentric orbit and the strewn fields for different mass/section ratio of the fragments. The trajectory was about from north to south and with low inclination (5^{circ } pm 2^{circ }) with respect to the local surface. The explosion height appears consistent with a fragmented rocky body, and the heliocentric orbit supports an asteroidal origin. The probable strewn field extends between two points with coordinates (+31.3^circ N; 96.3^circ E) and (+30.3^circ N; 96.5^circ E), for a total area of about 4000 text {km}^2. This large extension is a direct consequence of the low inclination of the trajectory. Given the unknown uncertainty of the CNEOS’s data, these results should be taken with caution.