>Supermassive black hole binary emits unexpected flares
This active galactic nucleus (AGN) flared so brightly that AT 2021hdr was almost mistaken for a supernova. Repeating flares soon ruled that out. When the researchers questioned whether they might be looking at a tidal disruption event—a star being torn to shreds by the black holes—something was still not making sense. They then compared observations they made in 2022 using NASA’s Neil Gehrels Swift Observatory to simulations of something else they suspected: a tidal disruption of a gas cloud by binary supermassive black holes. It seemed they had found the most likely answer.
“The variations in AT 2021hdr cannot be easily explained by any of the mechanisms usually associated to SMBHs,” the team said in a study recently published in Astronomy and Astrophysics.“However, we find that the behavior of AT 2021hdr broadly fits with models of the disruption and accretion of a gas cloud by a BSMBH.”
