[In Depth] Observations hint at a new recipe for giant black holes
Astronomers have glimpsed a new solution to a long-standing puzzle: how black holes could have grown fast enough to explain the monsters a billion times the mass of the sun seen soon after the big bang. Most black holes are thought to start out as collapsed stars, but they grow too slowly to fit the bill. Instead, theorists have suggested, the behemoth black holes in the early universe could have gotten a head start when huge gas clouds left by the big bang quickly shrank under their own gravity and condensed into black hole seeds 10 thousand to 100 thousand times heavier than the sun. Those seeds would have grown further by sucking in stars and gas. Last week, at the American Astronomical Society meeting in Grapevine, Texas, astronomers reported hints of such "direct collapse" black holes in x-ray and infrared surveys of the early universe. Author: Joshua Sokol