Portal:Radiation astronomy/X-ray astronomy article/24

Multiple X-ray sources have been detected in the Andromeda Galaxy, using observations from the European Space Agency XMM-Newton orbiting observatory.

Like the Milky Way, Andromeda's galactic center appears to harbor an X-ray source characteristic of a black hole of a million or more solar masses. Seen above, the false-color X-ray picture shows a number of X-ray sources, likely X-ray binary stars, within Andromeda's central region as yellowish dots. The blue source located right at the galaxy's center is coincident with the position of the suspected massive black hole. While the X-rays are produced as material falls into the black hole and heats up, estimates from the X-ray data show Andromeda's central source to be very cold - only about million degrees, compared to the tens of millions of degrees indicated for Andromeda's X-ray binaries.