Ring Around the Galaxy

A phalanx of black holes or neutron stars surrounds the ring galaxy AM 0644-741, which is about 300 million light-years from Earth. Another galaxy plunged through it in the distant past, altering its structure and triggering the birth of millions of new stars, which outline the oval-shaped ring. Some of those stars have exploded, leaving behind black holes or neutron stars that are pulling in the gas and dust around them. That makes them shine brightly in X-rays, which are seen as bright pink spots along the blue ring. This image combines visible and X-ray wavelengths observed by two space telescopes. [NASA/CXC/INAF/A. Wolter et al; NASA/STScI]