Quasar RX J1131-1231. Composite image of the quasar RX J1131-1231 made from combining data obtained by the Chandra X-ray Observatory (pink) and Hubble Space Telescope (red ,green and blue). Quasars are galaxies that are very distant but very luminous, so they appear star-like from Earth. The source of light appears concentrated in the nucleus, and is thought to be related to a central supermassive black hole. The Chandra data was used along with data from ESA's XMM-Newton to directly measure the spin of the supermassive black hole powering this quasar. At a distance of 6 billion light years from Earth, this is the most distant black hole where such a measurement has been made. Imaged on 28th November 2009.