Can you find Supernova 1987a ? It's not hard - it occurred in the center of the bulls-eye pattern. Although this stellar detonation was seen more than a decade ago, light from it continues to bounce off nearby interstellar dust and be reflected to us. These two rings are thus echoes of the powerful supernova . As time goes on, these echoes appear to expand outward from the center. The above image was created by subtracting a picture taken before 1987, from a picture taken after.
Media Credits & Attribution
Credit: Anglo-Australian Telescope photograph by David Malin Copyright: Anglo-Australian Telescope Board