The Bullet Cluster, located about 3.8 billion light years from Earth, formed after a violent collision of two giant clusters of galaxies. This image combines an X-ray image from Chandra with optical data from the Hubble Space Telescope and the Magellan telescope in Chile. Credit: X-ray: NASA/CXC/CfA/M.Markevitch et al.; Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al.
