Image: M31 Core in X-rays

Description: Using the newly unleashed observing power of the orbiting Chandra X-ray telescope, astronomers have now imaged the center of our near-twin island universe, finding evidence for an object so bizarre it would have impressed many 60s science fiction writers (and readers). 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 surprisingly cool - only a million degrees or so compared to the tens of millions of degrees indicated for Andromeda's X-ray binaries.
Title: M31 Core in X-rays
Credit: Astronomy Picture of the Day, url=http://apod.nasa.gov/apod/ap000121.html
Author: S. Murray, M. Garcia, et al., Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA) NASA Technical Rep.: Jay Norris.
Permission: Images produced by NASA are usually free of copyright [...]
Usage Terms: Public domain
License: Public domain
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