X-SciTech Views of The Antennae Galaxies August 5, 2010 / 12:15 PM EDT / CBS News Hot, interstellar gas mixes with rich deposits of elements from supernova explosions. Chandra X-ray Observatory Center The collision began more than 100 million years ago and is still occurring. Chandra X-ray Observatory Center Chandra X-ray Observatory Center Chandra X-ray Observatory Center