The Gamma-Ray Bubbles at the Center of the Galaxy

[piclink and article]

The universe is a surprising place. A new gamma-ray observatory has found these sharply defined bubbles of gamma rays to appear to be blown out from each end of the center of the galaxy. We're pretty sure what they're NOT -- dark matter -- but we don't really know what they ARE. Is this part of the reason why the rest of the galaxy might not be so habitable? Too many gamma rays? And we KNOW gamma rays turn mild-mannered Bruce Banner into the Hulk.

At the very least, it's a beautiful picture, and a reminder that even with the best observatories we only see through a glass darkly -- even if what we see is dark matter!