The universe’s biggest stars usually end their lives in dramatic supernova explosions before collapsing into black holes. But one gigantic star appears to have met a very different fate. Instead of going out in a brilliant burst, it wandered too close to a massive black hole, which ripped it apart and consumed it bit by bit.

Figure 1. Brightest-Ever Flare Erupts as Supermassive Black Hole Tears Apart Huge Star.

The brilliant flash originated from an active galactic nucleus (AGN)—a supermassive black hole that feeds on nearby matter. This particular AGN, called J2245+3743, is believed to contain a black hole roughly 500 million times the mass of the Sun and lies nearly 10 billion light-years away. Because its light has taken so long to reach us, astronomers are witnessing the event as it happened billions of years in the past, during a much earlier chapter of the universe’s history. Figure 1 shows Brightest-Ever Flare Erupts as Supermassive Black Hole Tears Apart Huge Star.

“The energy output tells us this object is both extremely distant and remarkably bright,” says lead author Matthew Graham, a Caltech astronomy research professor, ZTF project scientist, and one of the project’s co-principal investigators. “It behaves unlike any AGN we’ve encountered before.”

Time Dilation and a Cosmic Slow-Motion Show

Although the flare is slowly fading, astronomers continue to monitor it closely. Its extreme distance not only shows us an event from the distant past, but also affects how fast it appears to unfold. Time moves more slowly at the black hole’s location compared to Earth.

“This effect is known as cosmological time dilation, caused by the stretching of space and time,” Graham explains. “As light travels across the expanding universe to reach us, its wavelength lengthens — and so does time itself.”

This is one reason long-running sky surveys like ZTF and Catalina are so essential. In this case, Graham notes that “seven years here is two years there. We’re essentially watching the event in cosmic slow motion.”

A Star Torn Apart — The Tidal Disruption Event

To understand what could generate such an intense burst of light, the team examined several possibilities and determined that a tidal disruption event (TDE) is the most likely explanation. A TDE occurs when a star wanders too close to a supermassive black hole and is torn apart by its gravity, gradually being consumed as it spirals inward. The fact that J2245+3743 is still flaring suggests that we’re seeing a star only partly swallowed — “like a fish only halfway down the whale’s gullet,” Graham says.

If the flare indeed comes from a TDE, the researchers estimate that the black hole is devouring a star at least 30 times the mass of our Sun. The previous largest known TDE — nicknamed Scary Barbie after its ZTF designation, ZTF20abrbeie — was far less powerful. That event, also likely linked to an AGN, was 30 times weaker, and its doomed star was estimated at only 3–10 solar masses.

A Stellar Snack Inside a Black Hole’s Disk

Of the roughly 100 recorded TDEs, most have occurred outside active galactic nuclei (AGN). AGN contain supermassive black holes encircled by enormous, turbulent disks of gas and dust. Their constant feeding activity can produce flares of their own, sometimes masking the signatures of TDEs. But the flare from J2245+3743 was so immense that it stood out clearly.

Confirming the Unthinkable: A Star Devoured

“At first, we had to confirm that this extreme object was truly this bright,” says co-author K. E. Saavik Ford of CUNY and AMNH. One possibility was that the object was beaming its light directly toward Earth, instead of glowing equally in all directions. But data from NASA’s former WISE mission ruled that out. After eliminating other explanations, the team concluded that J2245+3743 represents the brightest black hole flare ever observed.

“If you converted our entire Sun into pure energy using Einstein’s E = mc², that’s comparable to the energy this flare has emitted since we started watching it,” Ford says.

Beyond Supernovae — A Rare Celestial Catastrophe

With its brightness confirmed, scientists turned to the question of what could generate such extraordinary power. A supernova was one idea, but the numbers didn’t add up.

“Supernovae simply aren’t bright enough,” Ford says. The evidence instead points toward a supermassive black hole pulling apart an enormous star.

“Stars this massive are uncommon,” she adds, “but we believe stars inside AGN disks can grow much larger. Material from the disk can build up on them, increasing their mass.”

A Window into the Cosmic Past

“We never would have detected this rare event without ZTF,” Graham says. “After seven years of watching the sky, we can track how things brighten, change, and evolve over time.”

Source: SciTECHDaily

Cite this article:

Priyadharshini S (2025), Supermassive Black Hole Unleashes Its Brightest Flare After Destroying a Massive Star, AnaTechMaz, pp.610