The gamma-ray of the black hole named Sagittarius A is fluctuating and is similar in periodicity in changes to the black hole's radio and X-ray emission.
For decades scientists have believed there is a black hole at the center of our Milky Way galaxy. For the first time this week, they released an astonishing image of it, about 27,000 light years away from Earth. An international collaboration of scientists and telescopes made the discovery. Miles O'Brien explores some of the mysteries surrounding the black hole.
Black holes are among the most profound predictions of Einstein's theory of general relativity. They were originally studied as a mere mathematical consequence of the theory rather than as physically relevant objects.