Thursday, September 20, 2007

Galaxy Plunges into Cluster

The almost 200,000 light year long comet-like tail was created as gas was stripped from ESO 137-001 while it plunges toward the center of Abell 3627, a giant cluster of galaxies.

Cool gas from the galaxy - only seen in optical images - is mixed in with hot gas from the cluster as seen in X-rays (blue).

Astronomers have found evidence that stars have been forming in the long tail of gas that extends well outside its parent galaxy. This discovery suggests that such "orphan" stars may be much more prevalent than previously thought.

This is one of the longest tails like this we have ever seen," said Ming Sun of Michigan State University, who led the study. "And, it turns out that this is a giant wake of creation, not of destruction."

"This isn't the first time that stars have been seen to form between galaxies," said team member Megan Donahue, also of MSU. "But the number of stars forming here is unprecedented."

The stars in the tail of this fast-moving galaxy, which is some 220 million light years away, would be much more isolated than the vast majority of stars in galaxies.
Orphan Stars Found in Long Galaxy Tail from Chandra