Black hole found that’s bigger than its galaxy suggests

Turns out you just never know where you might find a supermassive black hole.

For example, astronomers using the NASA/ESA Hubble Space Telescope and Gemini Telescope on Mauna Kea recently found one with a mass 17 billion times larger than the sun in the center of a galaxy — NGC 1600 — tucked away in the relative boondocks of the universe.

The astronomers’ findings are reported in the current edition of the science journal Nature.

The largest supermassive black holes are at least 10 billion times the mass of the Sun and have previously been detected only in very large galaxies in the centers of very large galaxy clusters.

NGC 1600 is an elliptical galaxy — that is, one with a more 3-D shape and less structure than a spiral galaxy — located in a relatively small group of 20 such galaxies located 200 million light-years away in the constellation Eridanus.

“Even though we already had hints that the galaxy might host an extreme object in the center, we were surprised that the black hole in NGC 1600 is 10 times more massive than predicted by the mass of the galaxy,” said lead author Jens Thomas of the Max Planck Institute for Extraterrestrial Physics in Germany.

As co-author Chung-Pei Man, an astronomer with the University of California-Berkeley noted, the discovery raises the possibility that supermassive black holes may be more common than previously thought.

“There are quite a few galaxies the size of NGC 1600 that reside in average-size galaxy groups,” he said.

“We estimate that these smaller groups are about 50 times more abundant than large, dense galaxy clusters. So the questions now is: Is this the tip of an iceberg? Maybe there are a lot more monster black holes out there.”

The researchers theorize that the black hole grew by merging with another supermassive black hole from another galaxy and continued to grow by consuming gas funneled to the core of the galaxy by other collisions. This would explain NGC 1600’s sparse surroundings and why it is at least three times brighter than neighboring galaxies.