A previously inactive supermassive black hole at the core of the galaxy SDSS1335+0728—located roughly 300 million light-years from Earth—has stunned astronomers by unleashing the most intense and prolonged X-ray bursts ever observed from such an object.
This dramatic shift marks the onset of the black hole actively feeding on surrounding matter, producing sudden and recurring flare-ups known as quasiperiodic eruptions (QPEs). These flares originate from a region known as an active galactic nucleus (AGN), now referred to by researchers as “Ansky.”
Ansky’s awakening was first detected in late 2019, prompting scientists to monitor its activity using NASA’s Swift X-ray space telescope. By February 2024, the black hole was consistently emitting powerful bursts of X-rays at regular intervals.
Joheen Chakraborty of the Massachusetts Institute of Technology (MIT), a member of the observing team, highlighted the unique nature of Ansky’s behavior: “The X-ray flares from Ansky last ten times longer and shine ten times brighter than typical QPEs. Each outburst releases a hundred times more energy than we’ve previously recorded.”
Chakraborty also pointed out that Ansky’s eruptions follow the longest regular cycle seen so far, recurring every 4.5 days. This unusual pattern is challenging existing scientific models and deepening the mystery around how such high-energy bursts are generated.
The team’s findings are based on observations from a range of space missions, including the European Space Agency’s XMM-Newton, NASA’s NICER and Chandra observatories, and archival data from eROSITA.
These discoveries offer fresh insights into the behavior of supermassive black holes and the extreme physical processes occurring in distant galaxies.
