A burst of activity in the middle of the Milky Way
Researchers detect the brightest flare ever observed in our galaxy's black hole. As black holes go, Sagittarius A* is relatively low-key. The black hole at the center of our galaxy emits very little energy for its size, giving off roughly as much energy as the sun, even though it is 4 million times as massive. However, astronomers have observed that nearly once a day, the black hole rouses to action, emitting a brief burst of light before settling back down. It's unclear what causes such flare-ups, and scientists have sought to characterize these periodic bursts in order to better understand how black holes evolve. Now a team of scientists from MIT, the University of Amsterdam, the University of Michigan and elsewhere have used NASA's Chandra X-Ray Observatory to detect the brightest flare ever observed from Sagittarius A*. The flare, recorded from 26,000 light years away, is 150 times brighter than the black hole's normal X-ray luminosity.

