A bizarre galaxy NASA spotted at the edge of the universe could upend what we know about supermassive black holes
WAIT, WHAT? THE UNIVERSE HAS AN EDGE?!
Marianne Guenot
Wed, December 27, 2023
A picture taken by JWST and Chandra X-ray observatory shows the location of a UHZ-1 and its black hole near the beginning of the universe.NASA/CXC/SAO/Ákos Bogdán; Infrared: NASA/ESA/CSA/STScI; Image Processing: NASA/CXC/SAO/L. Frattare & K. Arcand
NASA's JWST telescope spotted a bizarre galaxy that defies expectations.
Galaxy UHZ-1 formed around a huge black hole that existed surprisingly soon after the Big Bang.
It formed so early that the main theory for black-hole formation — a dying star — seems not to fit.
A bizarre galaxy spotted in the early days of the universe could rewrite how supermassive black holes are formed.
Scientists have long wondered how supermassive black holes — the enormous, mysterious phenomena at the center of galaxies including our Milky Way — came into existence.
A new observation of Galaxy UHZ-1, collected by NASA using its powerful new James Webb Space Telescope and the Chandra X-ray Observatory, suggests an unusual origin.
Per the agency, it could show that the supermassive black hole there was born directly from clouds of primordial gas.
If confirmed, it would show, for the first time, that supermassive black holes are not always formed by dying stars.
Such a discovery "changes the game in understanding how these objects formed," said study lead author Priyamvada Natarajan while speaking to Science Friday, a non-profit science-education organization.
"It is simply too big too early. It's like looking in at a kindergarten classroom and there among all the 5-year-olds is one that is 150 pounds and/or six feet tall," Daniel Holz, a theorist at the University of Chicago who studies black holes, told The New York Times.
"Priya has found an extremely exciting black hole, if true," he said.
Chandra X-ray Observatory first picked up the black hole by detecting X-rays let off by galaxy UHZ-1.
The black hole inside, the observatory found, was a beast — estimated between 10 million and 100 million times as massive as the sun, per New Scientist.
When JWST set out to figure out where the black hole was located, scientists got a shock: it was inside UHZ-1 about 13.2 billion light years away.
The distance meant that this behemoth existed when the universe was very young, only about 470 million years after the Big Bang. It's the furthest-flung black hole ever recorded.
And that's puzzling. One theory for the formation of supermassive black holes is that they come to be over a long time, The Times reported.
Stars at the beginning of the universe were small: they burned what was available, hydrogen and helium, which means they flamed out quickly, leaving smaller black holes about 10 to 100 times bigger than the sun in their wake, per a press release from NASA.
Over time, per this theory, black holes would merge, eventually forming supermassive black holes.
But UHZ-1 provides "compelling evidence" for another theory, said study author Natarajan, who is a professor of astronomy and physics at Yale.
Per this theory, black holes could be born big from the get-go. This type of galaxy, a big black hole surrounded by a small cloud of gas, could provide a heavy "seed" of a black hole that could grow into a supermassive black hole on its own.
Natarajan and her colleagues have dubbed this type of cluster "overmassive black hole galaxies."
The supermassive black holes, then, wouldn't be born from early stars. The best explanation instead, per Natarajan, is that they came from cosmic gas collapsing in on itself, creating seeds already weighing between about 10,000 and 100,000 suns.
"The fact that these start out in life overmassive implies that they will likely eventually evolve into supermassive black holes," said Natarajan, speaking to The Times.
"Nature does seem to make BH seeds many ways, beyond just stellar death!" she said, per the Times.
To confirm their theory, scientists will need more evidence, said Fabio Pacucci at the Harvard-Smithsonian Center for Astrophysics in Massachusetts, per New Scientist. "If this is at a 100 million solar masses it's pretty big, but if it's at 10 million solar masses it's not that big, so it could have possibly formed from a lighter seed," he said.
"Everything hinges on finding more of these objects, possibly more massive, possibly at even higher distances, to really understand how the first population of black holes formed."
The findings were published in a peer-reviewed study in the journal Nature Astronomy on November 6.
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