Astronomers, for the first time, have snapped an image of a cool, gassy ring swirling around the supermassive black hole at the center of our galaxy.
This ring is part of the so-called accretion disk — stars, dust and gases — that surround most black holes. These materials are held close by the black hole’s strong gravitational grip and the far edge represents the outer limits of its gravitational reach. In the case of the Milky Way’s black hole called Sagittarius A*, the disk extends out a few tenths of a light-year from the black hole’s event horizon — the point at which even light can’t escape the black hole’s grasp.
There are a few types of gases that make up parts of this accretion disk, and scientists previously have only imaged the very hot, glowing ones, according to a statement from the National Radio Astronomy Observatory. Because these gases are so hot — at about 18 million degrees Fahrenheit (10 million degrees Celsius) — they give off X-rays that researchers could easily detect.
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