Sextans A

Sextans A is a tiny dwarf irregular galaxy. It spans about 5000 light-years across, and is located at 4.3 million light-years away, in the outskirts of the Local Group of galaxies, which includes the Milky Way galaxy, and to which Sextans A may or may not belong.

Sextans A has a peculiar square shape. Massive short-lived stars exploded in supernovae that caused more star formation, triggering yet more supernovae, ultimately resulting in an expanding shell. Young blue stars now highlight areas and shell edges high in current star formation, which from the perspective of observers on Earth appears roughly square.

Image was acquired with CHI-1, data from 3 one-click observations

Total integration time: 260 minutes

LRGB 6:7:6:7 subs of 600s