Chandra Release - January 14, 2000

Visual Description: Andromeda Galaxy, M31

This Chandra X-ray Observatory image shows the central portion of the Andromeda Galaxy (or M31). At the center of the image, there is a bright, circular object that resembles a star. Surrounding this star, there are numerous small, bright dots, which appear to be evenly distributed across the image. These dots can be seen in different shades of purple, with some appearing brighter or dimmer than others and some with bright yellow cores. The blue dot in the center of the image is an unusually "cool" million degree X-ray source of unknown nature. Numerous other X-ray sources are also apparent. Most of these are probably due to X-ray binary systems, in which a neutron star or black hole is in a close orbit around a normal star.