Not sure if anyone can elaborate on why the light is this way. See following link:
http://antwrp.gsfc.nasa.gov/apod/ap100809.html
(Nice photo of it, also).
More detailed explanation of the star, ('bullet'), which they think disrupted the matter, go to:
http://www.jpl.nasa.gov/news/news.cfm?release=2009-002
Very similar to our conversation today on the Science Forum about Hyper Velocity Stars. What we're seeing in this one seems to be what happens to normal matter when one of these bullets ploughs thru a bunch of stuff.
Cheers & Rgds.