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Sagittarius A* in 60 Seconds
Narrator (April Hobart, CXC): Over several years, astronomers have noticed flares in X-ray light from the black hole at the center of the Milky Way. NASA's Chandra X-ray Observatory detected these flares during the telescope’s periodic observations of the black hole. A new study suggests that these flares may occur when the black hole – known as Sagittarrius A* or Sgr A* for short -- consumes an asteroid at least six miles wide. If an asteroid gets too close to another object like a star or planet, it can be thrown into an orbit headed toward Sgr A*. Once the asteroid passes within about 100 million miles of the black hole, it is torn into pieces by the black hole's tidal forces. Eventually, these fragments are vaporized by friction as they pass through the hot, thin gas flowing onto Sgr A*. This is what produces an X-ray flare. If confirmed, this result could mean that there is a cloud around Sgr A* containing trillions of asteroids and comets. This would be an exciting development for the many scientists who are fascinated by the Milky Way's giant black hole and the environment around it.