The Wide Field Infrared Survey Explorer (WISE) is an astronomy blogger's gift that keeps on giving. Observing huge swaths of the sky in the infrared, it sends back the coolest images! Behold:
Yeah, click that to get the most cromulently embiggened 4000 x 4000 pixel version. Those two galaxies are M82 (top) and M81 (bottom), and are both about 12 million light years away, relatively nearby as these things go. They are the two biggest galaxies in the M81 group, a collection of galaxies much like our own Local Group (dominated by our galaxy, the Milky Way, and Andromeda). M81 and M82 are almost certainly interacting with each, having had at least one pass sometime in the past, and may eventually merge in a billion years or so. Maybe less. Currently, they're roughly 300,000 light years apart. WISE sees them in the infrared, and in this picture blue represents the ...
