Astronomers have made a series of first-of-their-kind observations that uncover the dusty remains of stars ripped apart by supermassive black holes—occurrences known as tidal disruption events, which have long remained obscured from view.
The landmark detections were made possible by NASA’s James Webb Space Telescope and mark the first definitive signs of these dramatic phenomena in which dormant black holes, buried within galactic dust fields that render them invisible to astronomers, reanimate and consume a passing star.
The findings, which were published in Astrophysical Journal Letters, reveal new clues about the environments surrounding active versus dormant black holes, as well as Webb’s remarkable ability to detect cosmic cataclysms that otherwise remain hidden to astronomers.
Shedding Light on the Universe’s Star-Shredding Events
Since the 1990s, astronomers have observed close to 100 tidal disruption events, or TDEs, which appear as brief flares of light that signal when a star wanders too close to the black hole at its respective galaxy’s center.
Approaching the black hole, these stars are torn apart by the immense gravitational forces that are present near them. Although known to astronomers, these TDEs have been observed primarily in relatively dust-free galaxies through the detection of X-ray or optical light bursts. It has long been suspected that far more TDEs are occurring in regions where they aren’t easily seen—especially around dust-shrouded galaxies that hide these events from conventional tools available to astronomers.
In the past, scientists at MIT, Columbia University, and other institutions have demonstrated that while optical or X-ray light can be blocked by galactic dust accumulations, the same light can heat the dust in question, resulting in a distinctive glow detectable in the infrared.
In the new study, the team relied on Webb’s unparalleled infrared capabilities to detect those “hidden” signals in four galaxies, where previous research had revealed signatures associated with TDE activity, with the help of NASA’s NEOWISE mission.
Probing the Glow of Dormant Black Holes
The next phase of the research involved directing Webb’s powerful eye toward suspected locations where TDEs were likely to occur. By doing so, the team found unmistakable spectral fingerprints of black hole accretion, where high-energy swirling is generated, into which stellar debris begins to circle and eventually falls.
Among these signatures, the team observed rare infrared emission lines created when radiation from the accretion disk strips away electrons from neon atoms. This was a crucial observation, as it represents a phenomenon previously known to be produced only by black hole activity.
“There’s nothing else in the universe that can excite this gas to these energies, except for black hole accretion,” said lead author Megan Masterson, a graduate student at MIT’s Kavli Institute for Astrophysics and Space Research.
In all four instances, the team observed Webb detected dust patterns that appeared very different from those found in active galaxies, where the supermassive black hole at their center is constantly devouring stellar material. The absence of these patterns appears to suggest that these had been black holes that were dormant for a time, springing back into action whenever a star ventures too close.
This observation offered a key piece of evidence supporting the signals originating from TDEs.
From Tentative Signals to Bonafide TDEs
Building on earlier efforts that relied on NEOWISE, which scanned infrared data spanning a decade to identify brief flares in seemingly quiet galaxies to generate a dozen potential TDE candidates, the new Webb observations have now confirmed four of them. This includes the closest known TDE, which resides at a distance of only 130 million light-years.
“These four signals were as close as we could get to a sure thing,” Masterson said. “But the JWST data helped us say definitively these are bona fide TDEs.”
One of the four events was accompanied by X-ray emissions, while another had been previously mistaken for a supernova. Another of the events the team’s data has confirmed is one that produced a signal that may have originated from gas swirling at extreme velocities around a central black hole.
A New Tool to Decode the Behavior of Black Holes
Making the distinction between temporary accretion from a TDE and the ongoing feeding of an active galactic nucleus provided the researchers with a unique perspective on black hole activity in dusty galaxies, where it may have been previously overlooked. Next, the team plans to continue the search with both Webb and NEOWISE, as well as with future infrared telescopes.
Since tidal disruption events occur over long timescales, the team plans to make observations over several months, or even years, to reveal new insights into how these extreme cosmic events progress.
“The actual process of a black hole gobbling down all that stellar material takes a long time,” Masterson said. “It’s not an instantaneous process. And hopefully we can start to probe how long that process takes and what that environment looks like.”
For now, much about the conditions under which these monstrous events occur will remain mysterious, Masterson says.
“No one knows because we just started discovering and studying these events.”
The team’s open-access paper, “JWST’s First View of Tidal Disruption Events: Compact, Accretion-driven Emission Lines and Strong Silicate Emission in an Infrared-selected Sample,” was published in The Astrophysical Journal Letters on July 24, 2025.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.