An Extremely Luminous Flare Recorded from a Supermassive Black Hole
Abstract
Since their discovery more than 60 years ago, accreting supermassive black holes in active galactic nuclei (AGN) were recognized as highly variable sources, requiring an extremely compact, dynamic environment. Their variability traces to multiple phenomena, including changing accretion rates, temperature changes, foreground absorbers, and structural changes to the accretion disk. Spurred by a new generation of time-domain surveys, the extremes of black hole variability are now being probed. We report the discovery of an extreme flare by the AGN J224554.84+374326.5, which brightened by more than a factor of 40 in 2018. The source has slowly faded since then. The total emitted UV/optical energy to date is erg, i.e., the complete conversion of approximately one solar mass into electromagnetic radiation. This flare is 30 times more powerful than the previous most powerful AGN transient. Very few physical events in the Universe can liberate this much electromagnetic energy. We discuss potential mechanisms, including the tidal disruption of a high mass star, gravitational lensing of an AGN flare or supernova, or a supermassive (pair instability) supernova in the accretion disk of an AGN. We favor the tidal disruption of a massive star in a prograde orbit in an AGN disk.
Keywords
Cite
@article{arxiv.2511.02178,
title = {An Extremely Luminous Flare Recorded from a Supermassive Black Hole},
author = {Matthew J. Graham and Barry McKernan and K. E. Saavik Ford and Daniel Stern and Matteo Cantiello and Andrew J. Drake and Yuanze Ding and Mansi Kasliwal and Mike Koss and Raffaella Margutti and Sam Rose and Jean Somalwar and Phil Wiseman and S. G. Djorgovski and Patrik M. Veres and Eric C. Bellm and Tracy X. Chen and Steven L. Groom and Shrinivas R. Kulkarni and Ashish Mahabal},
journal= {arXiv preprint arXiv:2511.02178},
year = {2025}
}
Comments
41 pages, 12 figures, accepted by Nature Astronomy