Researchers discover a gigantic black hole that has awakened from its sleep after two decades.

In a remarkable new finding, researchers have found a supermassive black hole that has awakened from its slumber after being inactive for 20 years.

Found in the center of the SDSS1335+0728 galaxy within the Virgo constellation, situated approximately 300 million light years from Earth, the enormous black hole was identified by the Zwicky Transient Facility when it observed a rapid fluctuation in the galaxy’s brightness in late 2019.

The black hole, with a mass roughly one million times that of the Sun, has been emitting intense light across infrared, optical, and ultraviolet wavelengths for some time. Last year, however, Chilean astronomers observed it emitting X-ray bursts, indicating that the dormant black hole was rousing from its nearly two-decade-long sleep.

Shortly thereafter, it began consuming the surrounding gas, transforming the galaxy into one with an active galactic nucleus (AGN), with scientists dubbing it – Ansky. Subsequent measurements show that the black hole remains unsettled even after four years, significantly longer than the most brilliant supernova bursts. Nonetheless, the brightness remains less than that of quasars.

“Imagine you’ve been observing a distant galaxy for years, and it always seemed calm and inactive. Suddenly, its core starts showing dramatic changes in brightness, unlike any typical event we’ve seen before,” says Paula Sanchez Saez, the lead author of the study, who first noticed the massive black hole.

While it is not uncommon for black holes to go dormant for a few years, where they do not gobble up matter, this is the first time humans are observing a black hole transitioning from a quiet to active state. The observation might also help scientists study the evolution of galaxies and the growth of black holes, offering insights into how these cosmic phenomena work.