Rosat image of the Andromeda galaxy in the X-ray light.
As most galaxies, M31 has many star systems spewing high energy radiation. High energy X-radiation is visible only to certain satellites above planetary (i.e., Earth's) atmosphere such as ROSAT. The X-ray sources in M31 occur in globular clusters, the spiral arms, and near the galaxy's center. Probably most of these sources are accretion disk binary star systems. M31 has more X-ray sources near its center than our Galaxy, and the reason for this is currently unknown.
Last Modification: 2 Jul 1999