We’ve been sitting on this image since just before Christmas so that it could be unveiled during the BBC Stargazing Live show last night, but I’ve been aching to get this onto the blog ever since I saw it.
This is a Herschel image of our nearest neighbour galaxy, the Andromeda galaxy, also known as M31, along with comparison images at other wavelengths.
The Herschel data shows where stars are forming and where starlight is absorbed by dust. Images in the optical show us where stars are now, and the complementary X-ray data from XMM, ESA’s X-ray space telescope, show us where stars have died. The different locations picked out by these different wavelengths give hints as to how the Andromeda Galaxy has changed and evolved over its lifetime.
More information available from ESA, and from the BBC.