In a groundbreaking discovery, astronomers have witnessed a supermassive black hole awakening from dormancy and beginning to emit powerful radiation. This remarkable event marks the first time such a transition has been observed in real time.
The galaxy at the center of this cosmic drama is SDSS1335+0728, located a staggering 300 million light-years away. For decades, it remained quiet, but in December 2019, it suddenly came alive, emitting ultraviolet, optical, and infrared light into space.
By February of this year, the galaxy had escalated its activity, emitting X-ray light—an unprecedented phenomenon.
The leading theory is that SDSS1335+0728 harbors an active galactic nucleus (AGN), fueled by a supermassive black hole at its core. These AGNs draw energy from the black hole’s spin or the surrounding matter.
However, there’s a tantalizing possibility that it could also be a rare tidal disruption event (TDE), where a shredded star’s mass violently ejects outward, forming an accretion disk around the black hole.
The Zwicky Transient Facility telescope first detected the brightening of SDSS1335+0728 in the constellation Virgo. The supermassive black hole at its center weighs approximately one million solar masses.
To unravel the mystery, astronomers meticulously analyzed archival data and combined it with new observations from various instruments, including the X-shooter on the Very Large Telescope (VLT) in Chile’s Atacama Desert.
The glow observed in SDSS1335+0728 results from cold dust and gas surrounding the black hole, forming orbiting accretion disks. Gravitational forces compress the matter, heating it to millions of degrees Kelvin, producing radiation across the electromagnetic spectrum.
While the AGN explanation seems most likely, there’s room for speculation. Could this be an exceptionally long and faint TDE—the longest and faintest ever detected? Or perhaps an entirely new phenomenon? Astronomers are closely monitoring SDSS1335+0728, preparing for follow-up observations with the VLT’s Multi Unit Spectroscopic Explorer (MUSE) and the upcoming Vera Rubin Observatory’s Large Synoptic Survey Telescope (LSST).
