X-ray and optical view of the Coma galaxy cluster

This image shows the bright, nearby, and massive Coma galaxy cluster in X-ray and optical light, as seen by XMM-Newton’s European Photon Imaging Camera (EPIC) and the Sloan Digital Sky Survey (SDSS).

Using XMM-Newton to study Coma and another notably massive cluster, Perseus, astronomers spotted the first signs of gas sloshing around in Perseus – a behaviour that, while predicted, had never been seen before – while Coma appears to comprise two major sub-clusters that are slowly merging together.

Full story: First sighting of hot gas sloshing in galaxy cluster