Stephan's Quintet: A group of galaxies that is located about 280 million light years from Earth.
Caption: This composite image of X-rays from Chandra (colored light blue) and optical data from the Canada-France-Hawaii Telescope (yellow, red, white, and blue) shows a beautiful new look at the compact group of galaxies known as Stephan’s Quintet. One galaxy is thought to be passing through the others at almost two million miles per hour. This generates a shock wave that heats the gas and creates the ridge of X-ray emission detected by Chandra.
Scale: Image is
6.3 arcmin across.
Chandra X-ray Observatory