A PAIR of quasars long thought to be an optical illusion are actually two distinct objects. The chance of finding two identical-looking quasars, or supermassive black holes, in the same place is 鈥渧irtually nil鈥�, according to Paul Green of the Harvard-Smithsonian Center for Astrophysics. So astronomers assumed that light from a single quasar must be getting bent by a massive object in its path, making it look like a pair, dubbed Q2345+007 A and B.
But when Green focused the Chandra X-ray telescope on the spot for 20 hours, he found no such mass and that the pair鈥檚 X-ray spectra differ. He concludes that there really are two quasars which are at the hearts of neighbouring galaxies just 200,000 light years apart.