Milky Way's enormous black hole gorges on asteroids (+video)
British astrophysicists think that asteroids are being devoured by the supernassive black hole at our galaxy's center, as evidenced by the daily X-ray flares detected by NASA's Chandra space telescope. Historical records indicate tha black hole may have even swallowed a planet.
NASA/CXC/MIT/ Illustrations: NASA/CXC/M.Weiss
The gigantic black hole at the heart of our Milky Way galaxy may be devouring asteroids on a daily basis, a new study suggests.
For several years, NASA's Chandra spacecraft has detected X-ray flares about once a day coming from our galaxy's central black hole, which is known as Sagittarius A* (Sgr A* for short). These flares may be caused by asteroids falling into the supermassive black hole's maw, according to the study.
"People have had doubts about whether asteroids could form at all in the harsh environment near a supermassive black hole," study lead author Kastytis Zubovas, of the University of Leicester in the United Kingdom, said in a statement. "It's exciting because our study suggests that a huge number of them are needed to produce these flares."
Asteroids circling a black hole
Zubovas and his colleagues suggest that a cloud around Sgr A* contains trillions of asteroids and comets that the black hole stripped from their parent stars.
Asteroids passing within about 100 million miles (160 million kilometers) of the black hole — roughly the distance between the Earth and the sun — are likely torn to pieces by Sgr A*'s gravity, according to the study.
These fragments would be vaporized by friction as they encounter the hot gas flowing onto the black hole, much as meteors are burned up by the gases in Earth's atmosphere. This vaporization likely spawns the X-ray flares, which last for a few hours and range in brightness from a few times to nearly 100 times that of the black hole's regular output, researchers said.
Sgr A* then swallows up what's left of the close-flying asteroid.