Small Black Hole Gobbles Dust and Gas with Surprisingly Good Manners

Black holes can gobble down dust and gas, consuming material at a rapid pace. Just how rapid this pace is, though, largely depends on the size of the black hole. Now, astronomers have found a new black hole that may change that line of thinking. They've discovered a relatively lightweight black hole that's consuming a prodigious amount of dust and gas. Not only that, this black hole is swallowing the material in a surprisingly orderly fashion.

"It has elegant manners," said Stephen Justham, one of the researchers, in a news release. "We thought that when small black holes were pushed to these limits, they would not be able to maintain such refined ways of consuming matter. We expected them to display more complicated behavior when eating so quickly. Apparently we were wrong."

The black hole itself is located in a galaxy about 22 million light-years away. Powering an energetic X-ray source, this black hole was first thought to be massive. X-ray sources give off high- and low-energy X-rays, which astronomers call hard and soft X-rays respectively. Larger black holes tend to give off more soft X-rays, which this particular black hole was giving off.

Yet it turns out that the black hole is surprisingly small, though astrophysicists still don't understand why that is. In theory, the region around the black hole should be dominated by hard X-rays and appear more structurally complicated.

"Theories have been suggested which allow such low-mass black holes to eat this quickly and shine this brightly in X-rays," said Jifeng Liu, one of the researchers, in a news release. "But those mechanisms leave signatures in the emitted X-ray spectrum, which this system does not display. Somehow this black hole, with a mass only 20-30 times the mass of our Sun, is able to eat at a rate near to its theoretical maximum while remaining relatively placid. It's amazing. Theory now needs to somehow explain what's going on."

Currently, the researchers plan on studying this black hole a bit more closely in order to learn a bit more about its bizarre behavior. This, in turn, could help create future models that predict black hole behavior.

The findings are published in the journal Nature.