ASASSN-21qj

ASASSN-21qj, also known as 2MASS J08152329-3859234, is a Sun-like main sequence star with a rotating disk of circumstellar dust and gas which are leftovers from its stellar formation around 300 million years ago.

The star is located 1,850 light years (567.2 parsecs) from Earth in the constellation of Puppis.

[5] In 2021 the All-Sky Automated Survey for Supernovae reported that this star was rapidly fading.

[7][2] In 2023, a scientific paper reported observations consistent with two ice-giant type exoplanets of several to tens of Earth masses having undergone a planetary collision event.

Because of the dust cloud had now reached a large size, the dimming event would last for 600 days.