... What's happening in the middle of this massive galaxy? There, two bright sources at the center of this composite x-ray (blue)/radio (pink) image are thought to be co-orbiting supermassive black holes powering the giant radio source 3C 75. ... Only 11 million light-years away, Centaurus A is the closest active galaxy to planet Earth. ... The two galaxies on the far left were unknown until 1968. ... Deep Auriga . ... The plane of our Milky Way Galaxy runs right through Auriga, the Charioteer. ...