galaxy is estimated to harbor only one supernova every several hundred years. Astonishingly, this starburst was concentrated within a small part of the galaxy no more than 1,000 light years across.
The overall picture of M82 as an exploding galaxy has changed as astronomers have added radio observations to their repertoire. Instead of being torn apart by a single catastrophic event, M82 was more likely the site of a strong nuclear starburst. Replacing the theory of a single, unimaginably large explosion is one of an epoch of millions of supernovae caused by giant, young stars. The shells of expanding gas could have created the streamers seen in optical and H alpha images.
