Beefing Up the Universe's Biggest Black Holes

When it comes to black holes lurking within the hearts of galaxies, there's some real monsters out there. Measured in the millions to billions of solar masses, these incredibly dense cosmic objects pack so much material into so small an area that not only can light not escape, but their gravity traps entire clusters of stars in breakneck orbits around them -- and at close proximity they even warp the very nature of physics itself.

On occasion their powerful outbursts create beacons of high-energy radiation that can be seen from clear across the Universe.

Many galaxies, if not all, are home to enormous black holes at their center -- our own Milky Way being no exception. The supermassive black hole in the heart of our galaxy, Sgr A*, is estimated to weigh in at a hefty 4 million solar masses. That may sound impressive, but even this is literally dwarfed by what astronomers have discovered with NASA's Chandra X-ray Observatory (along with radio data from the NSF's Karl G. Jansky Very Large Array, the Australia Telescope Compact Array and infrared data from the 2 Micron All-Sky Survey): ultramassive black holes lounging in the centers of distant galaxies, containing the equivalent masses of 10 to 40 billion suns.

Yes, I said billion.

During a survey of 18 galaxy clusters, Chandra detected enormous outbursts of energy from ten of the brightest galaxies -- such as the elliptical galaxy at the center of PKS 0745-19, seen above. These outbursts have cleared dark gaps in the hot, x-ray bright gas clouds surrounding the clusters, preventing the diffuse gas from condensing to form stars.

Because outbursts of this size would have to be fueled by the consumption of enormous amounts of material -- capable by only the most massive black holes -- scientists have calculated that these must be truly ultra-ultramassive... up to ten times more massive than earlier estimates. And if ten of these behemoths have been found in such a small collection of galaxies, it stands to reason that there must be more -- lots more.

"Our results show that there may be many more ultramassive black holes in the universe than previously thought," said study leader Julie Hlavacek-Larrondo of Stanford University.

More research and modeling will be needed to confirm the team's results, including comparison to a known ultramassive black hole in the galaxy M87, located in the nearby Virgo cluster of galaxies.

"If our results are confirmed, they will have important ramifications for understanding the formation and evolution of black holes across cosmic time," Hlavacek-Larrondo said. "I wouldn't be surprised if we end up finding the biggest black holes in the Universe."

Read more at Discovery News