Map: X-Ray Vision Shows How a Galaxy Cluster Grows

Astronomers first discovered a hint of this cometlike ball of gas careering through a distant cluster of galaxies called Abell 3266 two years ago, but they didn't know what to make of it. It doesn't emit visible light. But now astrophysicists have mapped its thermodynamics using X-ray data caught by the European Space Agency's XMM-Newton satellite in a high-speed camera chase. And as it turns out, this fireball is full of surprises.