A global team of astronomers, led by Harvard scientists, have for the first time captured an image of a black hole.
The image, revealed today by researchers from the Event Horizon Telescope (EHT), shows a bright ring of material surrounding a dark center that marks the event horizon of the black hole — the “point of no return, where nothing, not even light — can escape.”
The image is the result of a colossal, years-long effort by dozens of researchers. To find it, the EHT focused on a pair of supermassive black holes — the one at the center of the Milky Way galaxy, known as Sagittarius A* (pronounced Sagittarius A-star), and a second that lies at the heart of an elliptical galaxy called M87.
Capturing an image of a black hole, project leaders said, is about more than getting the first glimpse of one of the most curious objects in the cosmos. It also opens the door to allowing astronomers and physicists to test Einstein’s theories of gravity and general relativity under the most extreme conditions in the universe.
“A black hole, if you looked at it naked … would be invisible,” said Sheperd Doeleman, director of the EHT. “It’s nature’s most amazing invisibility cloak.”
So how do you take a picture of something from which even light cannot escape?
“In a paradox of its own gravity,” Doeleman explained, “you wind up seeing it because all the gas and dust that’s attracted to it gets crushed into a smaller and smaller volume, causing it to heat up to hundreds of billions of degrees. So you wind up with a 3-D flashlight illuminating all the space-time around the black hole.” (Harvard)