RCW 86: A supernova remnant in the Milky Way, about 8,200 light years from Earth.
Caption: This composite image of X-ray data from Chandra (blue) and optical data from the Very Large Telescope (red) shows part of the roughly circular supernova remnant known as RCW 86. New details about the role of supernova remnants as the Milky Way’s super-efficient particle accelerators have emerged thanks to this combined study. Astronomers have shown that the shock wave visible in this area is very efficient at accelerating particles and the energy used in this process matches the number of cosmic rays observed on Earth.
Scale: Image is about
6 arcmin across.
Chandra X-ray Observatory