In 2014, astronomers detected an unusual feature in X-ray data from Perseus and other galaxy clusters. Since then, Chandra and other X-ray telescopes have taken more observations to replicate the finding. The existence and interpretation of this spike in X-ray light has been controversial and difficult to explain. Now, a new team of astronomers has reanalyzed these and other data and come up with a fresh take on this debate. They suggest that dark matter particles in the galaxy clusters are both absorbing and emitting X-rays. If the new model turns out to be correct, it could provide a path for scientists to identify the true nature of dark matter.
