Astronomers at Swinburne University of Technology were instrumental in the discovery of a rare, luminous jet of matter moving at near the speed of light, created by a supermassive black hole that violently shatters a star. published in the magazine Nature The work brings astronomers closer to understanding the physics of supermassive black holes at the centers of galaxies billions of light-years away. Swinburne Professor Geoff Cook, who is also Principal Investigator of the ARC Center of Excellence for Gravitational Wave Discovery (OzGrav), was a key member of the research team.

“Stars literally being torn apart by the gravitational tidal forces of black holes help us better understand what’s going on in the universe,” says Professor Cook. “These observations help us discover extreme physics and energy that could not be created on Earth.”

Supermassive, extremely rare and extremely distant

When a star gets too close to a supermassive black hole, the star is violently shattered by tidal forces and the pieces are pulled into orbit around the black hole, eventually being completely absorbed by the black hole. In extremely rare cases – only one percent of cases – these so-called tidal disruption events (TDEs) also initiate jets of luminous material that travel at nearly the speed of light.

Co-authors of the paper are University of Maryland’s Dr. Igor Andreoni and Associate Professor Michael Coughlin of the University of Minnesota, along with an international team, observed one of the brightest TDEs in history. They measured it 8.5 billion light-years away, or more than half the observable universe.

Officially called ‘AT2022cmc’, the event is believed to be at the center of the galaxy and is not yet visible as the intense light from this center flare still overshadows it. Future space observations may reveal the galaxy as AT2022cmc eventually disappears.

It’s still a mystery why some TDEs launch jets while others don’t. From their observations, the researchers concluded that black holes associated with AT2022cmc and other similar jet TDEs are spinning rapidly. This suggests that a rapidly spinning black hole could be one of the necessary components to launch a jet; It’s an idea that brings researchers closer to understanding these mysterious objects in the far reaches of the universe.

Collaboration for new discoveries

More than 20 telescopes operating at all wavelengths were part of this work. These include the Zwicky Transient Facility in California, which made the first discovery, X-ray telescopes in space and on the International Space Station, radio/mm telescopes in Australia, the United States, India and the French Alps, and optical/infrared telescopes in the United States. Chile, the Canary Islands and the USA, including the WM Keck Observatory in Hawaii.

Swinburne doctoral student Jilai Zhang, co-author of the study, says international collaboration is essential for the discovery.

“Although the night sky may seem calm, telescopes reveal that the universe is full of mysterious, explosive and transient events waiting to be discovered. Thanks to the international research collaboration between OzGrav and Swinburne, we are proud to make important discoveries like this.”