NASA - National Aeronautics and Space Administration

Galaxy C153, a spiral galaxy that was once like our own Milky Way, is meeting an unusually rapid and violent death as it careens through the heart of a distant cluster of galaxies.

"It's a clear case of galaxy assault and battery," says William Keel of the University of Alabama.

Images taken by X-ray, optical and radio telescopes were combined to reveal some "forensic evidence" of the galaxy's late life.

This composite image was made by combining images taken in X-ray, radio, and visible wavelengths as well as the visible, green light emitted by oxygen ions.

Astronomers hope to use the discovery to learn why spiral galaxies, once abundant in rich clusters of galaxies, have disappeared over time.

The Very Large Array radio telescope first detected this galactic mayhem in 1994, and found evidence that C153 contains a very active, supermassive black hole. X-ray observations from the Roentgen Satellite (ROSAT) showed that the galaxy is located in a massive cloud of 36-million-degree Farenheit gas.

Astronomers turned to the Kitt Peak National Observatory for an optical spectrum analysis, which produced dramatic color photomaps of the cluster and found that stars were forming at an unusually high rate in C153.

NASA's Hubble Space Telescope has since determined that the galaxy is home to many young star clusters and chaotic dust features. This recent star formation is a major contributor to a long tail of light, a finding that provides a direct link to the stripping of the galaxy.

NASA's Chandra X-ray Observatory discovered that the cooler clouds identified by the optical telescopes are embedded in a much larger, multimillion-degree trail of gas. Observations indicate that this hot gas was probably enriched in heavy elements by the starburst, and is being driven out of the galaxy as it speeds through the larger cloud of gas.

As it races through the cluster, Galaxy C153 is destined to have the last of its spiral arms ripped away, turning it into a bland galaxy with only a central bulge and disk. These types of galaxies are common in the dense galaxy clusters seen today. Astronomers plan to make new observations in 2004 to study the dynamics of the gas and stars in the tail.

To view the full text of this release, visit:
http://chandra.harvard.edu/photo/2004/c153/

Additional information and images are available at:
http://chandra.harvard.edu and http://chandra.nasa.gov
NASA's Chandra X-ray Observatory