One of the universe’s largest “prisons” is just 200 million light years away, suggest findings on black holes by UC Berkeley researchers.
A study led by Chung-Pei Ma, astronomy professor at UC Berkeley, discovered a “supermassive black hole” with a mass equivalent to 17 billion suns. The study was published Wednesday in the journal Nature.
A black hole is a region of space where matter has been compressed to such a small volume that nothing can escape from it, according to an email from UC Berkeley astronomy professor Alex Filippenko. The inability of light to escape makes the region appear black, which is why it is called a “black hole.”
“A black hole is a structure of space (and) time,” said Avi Loeb, chair of the astronomy department at Harvard University. “(It’s the) ultimate prison that nothing can escape from — not even light.”
The black hole was discovered in the galaxy NGC 1600 through the MASSIVE Survey, a controlled, systematic study of the 100 most massive galaxies up to about 300 million light years away from Earth, according to Ma.
What made NGC 1600 interesting to researchers was that though it is one of the most luminous galaxies, it does not have many galaxies around it, and those surrounding it are fainter, explained Nicholas McConnell, a postdoctoral fellow for the National Research Council of Canada and a researcher for the project.
“It’s like one large great white shark with quite a lot of guppies surrounding it,” McConnell said.
Ma said that like people, bigger galaxies also group together into clusters, where the environment is more conducive to forming bigger black holes. Therefore, past studies focused on finding black holes in “special galaxies,” the center of clusters containing thousands of galaxies, according to Ryan Janish, a graduate student in the campus physics department and a researcher for the project.
The MASSIVE project, however, examines ordinary galaxies.
“(The) unusual thing is that (the black hole is) located in a pretty isolated galaxy. It’s like a cosmic backwater,” Ma said. “In a dense place like San Francisco, (the) chance of collision is much higher, so it’s easier to make a bigger black hole.”
She pointed out that the isolation of NGC 1600 made it an unusual site for such a massive black hole.
According to an email from Filippenko, supermassive black holes may have been brilliant “quasars” billions of years ago. Quasars are sources of light resulting from the growth of black holes.
“Monster black holes are like quasars in retirement,” Ma said.
Janish said the discovery may suggest that black holes are very common. According to Loeb, however, more black holes need to be found before scientists can determine if such massive black holes commonly exist in modest galaxies.
“(The black hole) helps us just understand the big picture of how the universe forms and evolves,” Janish said. “The way that whole process works is still one of the biggest unsolved questions in astrophysics.”
Ma said NGC 1600 was just one of the first several hundred galaxies the survey had analyzed, with data for many more to come.
“We want to see if this is a rare find or the tip of the iceberg,” Ma said.