Cosmic wow, a rare exploding star!

Updated 12:51 PM EST, Fri January 24, 2014

Story highlights

In one of the nearest big galaxies, M82, a rare type of supernova exploded

Meg Urry: Its uniform luminosity makes it valuable in measuring cosmic distance

She says finding supernovae has led directly to the discovery of dark energy

Urry: We are seeing this light 11.4 million years after the real explosion