Swift Ultraviolet/Optical Telescope image of Supernova 2006jc in the galaxy UGC 4904 in three filters. Credit: NASA/Swift/S. Immler
SN 2006jc was a supernova that was detected on October 9, 2006 in the galaxy UGC 4904, which is about 77 million light-years away in the constellation Lynx. It was first seen by Japanese amateur astronomer Koichi Itagaki, American amateur Tim Puckett and Italian amateur Roberto Gorelli. Two years earlier, the progenitor star produced a supernova impostor that was detected by Itagaki. This outburst was apparently the progenitor star shedding its outer layers. When the star exploded in 2006 the shock wave hit the material blown off in 2004, heating it to millions of degrees and emitting copious amounts of X-rays.