Astronomers detected the most energetic flare ever seen from a supermassive black hole, likely caused when the hole tore apart and consumed an unusually massive star. The burst reached about 10 trillion times the Sun's brightness from a black hole of roughly 300 million solar masses, located 11 billion light-years away. The flare brightened ~40×, peaked in June 2018 at roughly 30× the luminosity of previous black hole flares, and is still fading over an expected ~11-year timespan.
Record-Breaking Black Hole Flare: Monster Star Torn Apart Sparks Most Energetic Blast Ever Seen
Astronomers detected the most energetic flare ever seen from a supermassive black hole, likely caused when the hole tore apart and consumed an unusually massive star. The burst reached about 10 trillion times the Sun's brightness from a black hole of roughly 300 million solar masses, located 11 billion light-years away. The flare brightened ~40×, peaked in June 2018 at roughly 30× the luminosity of previous black hole flares, and is still fading over an expected ~11-year timespan.
20:57, 04.11.2025Science
Record-Breaking Flare From a Supermassive Black Hole
Scientists have observed the most energetic flare ever recorded from a supermassive black hole — a burst so powerful it appears to have been triggered when the black hole shredded and consumed an extraordinarily massive star that wandered too close.
How powerful? At its peak the flare was about 10 trillion times more luminous than the Sun. The source is a black hole roughly 300 million times the mass of the Sun, located in a galaxy some 11 billion light-years from Earth (a light-year is about 5.9 trillion miles or 9.5 trillion kilometers).
Black holes are extremely dense objects whose gravity is so strong that not even light can escape. The black hole tied to this flare is vastly more massive than the one at the center of our Milky Way, which is roughly 4 million solar masses.
What likely happened
The research team concludes the most plausible explanation is that a very large star — estimated at a minimum of about 30 solar masses and perhaps as much as 200 — was pulled onto a fatal orbit and torn apart. As stellar debris fell inward and heated up, it produced the intense flare when it reached the black hole's point of no return.
"It seems reasonable that it was involved in a collision with another more massive body in its original orbit around the supermassive black hole which essentially knocked it in," said Caltech astronomer Matthew Graham, lead author of the study published in Nature Astronomy.
Co-author K.E. Saavik Ford added that the star was likely "spaghettified" — stretched into a long, thin stream by the black hole's tidal forces — and that this heated gas then spiraled around and into the black hole, producing the flare.
Observations and alternatives considered
Astronomers monitored the event with telescopes in California, Arizona and Hawaii. They considered other explanations — including a supernova, an outward-directed jet from the black hole, or gravitational lensing that could magnify a fainter event — but found those scenarios inconsistent with the data.
The flare brightened by a factor of about 40 while under observation and reached its peak in June 2018. At its brightest it was roughly 30 times more luminous than any previously observed black hole flare. The event is still fading and is expected to decline over an overall timespan of roughly 11 years.
Looking back in time
Because the source is 11 billion light-years away, astronomers are seeing the event as it occurred in an earlier epoch of the universe. The continued fading of the flare will provide additional information about how tidal disruptions of massive stars unfold around supermassive black holes.
Reporting by Will Dunham; edited for clarity.