In May, the supermassive black hole in the core of the Milky Way became 75 times brighter in just two hours.
The supermassive black hole at the center of our galaxy has been mysteriously shining lately, and no one knows why. Sagittarius A is four million times more massive than the sun. Astronomers can see the hole’s interaction with bright stars or the dust clouds surrounding it, although they cannot see it.
An astronomer at the University of California, Tuan Do, and his colleagues observed Sagittarius A with the Keck Telescope at the top of Mount Mauna Kea in Hawaii. In just two hours, they witnessed the black hole become ten times brighter in the near infrared light spectrum.
“The brightness of Sagittarius A changes all the time, getting brighter and weaker on a scale from minutes to hours – mostly it flickers like a candle. We think something unusual might happen this year because a black hole is brighter than we’ve ever seen in the past,” says Do.