NGC 4449, the Box Galaxy, (also known as Caldwell 21) is an irregular dwarf starburst galaxy. It is located approximately 12 to 13 million light-years from Earth in the constellation Canes Venatici. It is a member of the M94 group of galaxies. Its exceptionally high rate of star formation is notable. This feature earns it the “starburst” designation.
Unlike many galaxies where star formation is central, NGC 4449 exhibits widespread star formation. It reaches all the way to its edges. This is likely triggered by gravitational interactions or past mergers with smaller companion galaxies. The galaxy is rich in blue star clusters, which are young and massive stars. It also contains reddish regions of ionized hydrogen. In these regions, new stars are actively being born.
