Is it possible for black holes to form without the implosion of a star?

How many ways are there to leave our universe?

Perhaps the most well-known exit involves the death of a star. In 1939, physicist J. Robert Oppenheimer and his student Hartland Snyder predicted that when a sufficiently massive star runs out of thermonuclear fuel, it collapses inward and continues to collapse forever, contracting the space, time, and light around it into what today is called a black hole.

But it may not take a dead star to form a black hole. Instead it is possible, at least in the early universe, that giant clouds of primordial gas have collapsed directly into black holes, bypassing millions of years spent in stardom.

That's the tentative conclusion recently reached by astronomers studying UHZ-1, a powerful quasar that spewed fire and X-rays from a monstrous black hole 13.2 billion years ago, when the universe was not even 500 million years old.

Priyamvada Natarajan, an astronomer at Yale University and lead author of a new study, and her colleagues argue that at UHZ-1 they have discovered a new celestial species, called a supermassive black hole galaxy, or OBG—a young galaxy anchored by a black hole. that got too big too quickly.

The discovery could help astronomers solve a puzzle that has puzzled them for decades. Almost all visible galaxies seem to harbor at their center a supermassive black hole millions or billions of times more massive than the Sun. Where did they come from? Could ordinary black holes have grown so big and so fast?

Natarajan and his colleagues propose that UHZ-1, and perhaps many other supermassive black holes, began as primordial clouds, which could have collapsed into nuclei that were precociously heavy and sufficient to drive the growth of galaxies with supermassive black holes.

Natarajan's team used NASA's Chandra X-ray Observatory to observe UHZ-1. The quasar was powered by a supermassive black hole about 40 million times more massive than the Sun. Other observations by the James Webb Space Telescope confirmed that UHZ-1 was 13.2 billion light years away. It is the most distant and oldest quasar found so far in the universe.

The results indicate that supermassive black holes already existed 470 million years after the Big Bang. That's not enough time to allow the black holes created by the first generation of stars to grow that large.

As soon as the Webb Telescope pointed to the sky after its launch two years ago, it saw new galaxies so massive and bright that they defied expectations. Discussions have since arisen over whether these observations threaten a long-held model of the cosmos. The model describes the universe as composed of some visible matter, staggering amounts of “dark matter,” which provides the gravity to hold galaxies together, and “dark energy,” which pulls them apart.

The discovery of UHZ-1 represents a turning point in these debates.

By: DENNIS OVERBYE