James Webb telescope spots 2 monster black holes merging at the dawn of time, challenging our understanding of the universe

Astronomers have used the James Webb Space Telescope (JWST) to detect the most distant pair of colliding black holes in the known universe. The cosmic monsters — each estimated to be as massive as 50 million suns — have been detected more than 13 billion light-years away, at a time just 740 million years after the Big Bang.

While not the biggest or oldest black holes ever detected, the merging pair have still managed to grow bafflingly large for such an early time in the universe's history, the study authors said in a European Space Agency (ESA) statement. This discovery further challenges leading theories of cosmology, which fail to explain how objects in the universe's infancy could grow so large, so fast.

"Our findings suggest that merging is an important route through which black holes can rapidly grow, even at cosmic dawn," the study’s lead author Hannah Übler, a researcher at the University of Cambridge, said in the statement. "Together with other Webb findings of active, massive black holes in the distant Universe, our results also show that massive black holes have been shaping the evolution of galaxies from the very beginning."

Black holes are extraordinarily massive objects with a gravitational pull so strong that nothing, not even light, can escape their clutches. They are thought to form when massive stars collapse in supernova explosions, and they grow by endlessly swallowing up the gas, dust, stars and other matter in the galaxies that surround them.

The hungriest, most active black holes may reach supermassive status — bulking up to be anywhere from a few hundred thousand to several billion times the mass of the sun. One key way that supermassive black holes may reach such gargantuan sizes is by merging with other large black holes in nearby galaxies — a phenomenon that's been detected at various times and places throughout the universe.

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The new discovery comes courtesy of JWST's powerful NIRCam infrared instrument, which can detect the light of ancient objects across vast cosmic distances and through obscuring clouds of dust. 

In the new study, published Thursday (May 16) in the Monthly Notices of the Royal Astronomical Society, researchers trained the JWST's infrared cameras on a known black hole system called ZS7, located in an early epoch of the universe known as cosmic dawn. Previous observations showed that the system hosts an active galactic nucleus —- a feeding, supermassive black hole at the galaxy's center, which emits bright light as hot gas and dust swirls into the black hole's maw.