Chandra X-ray, MERLIN Radio and SDSS Optical Images of HDF 130
These images of X-ray data from Chandra, radio emission from MERLIN, and optical data from SDSS show a small region of the Chandra Deep Field North, one of the deepest X-ray images ever obtained. The diffuse blue object near the center is thought to be a cosmic "ghost" generated by a huge eruption from a supermassive black hole in a distant galaxy. This X-ray ghost remains long after radio waves from the source have died off, giving astronomers an opportunity to study this phenomenon in the early Universe.
(Credit: X-ray (NASA/CXC/IoA/A.Fabian et al.); Optical (SDSS), Radio (STFC/JBO/MERLIN))