A team of astronomers from MIT and Columbia University has made a groundbreaking discovery using the James Webb Space Telescope (JWST). For the first time, phenomena known as tidal disruption events (TDEs)—in which stars are torn apart by black holes—have been observed hidden within galaxies shrouded in dust and gas. 

A TDE occurs when a star comes too close to the central black hole of a galaxy and is ripped apart by its tidal forces. This results in a powerful burst of energy, previously observed mainly in X-ray or visible light wavelengths—and only in relatively “clean” galaxies free of obscuring dust. 

The authors of the study published in Astrophysical Journal Letters suggest that many such events may remain hidden in dusty galaxies, undetectable by conventional telescopes. 

This time, scientists utilized JWST’s infrared detection capabilities to peer through the dust and confirm the presence of a black hole devouring a star in four distant galaxies. The telescope recorded characteristic spectral lines—radiation at specific wavelengths—which serve as the “fingerprint” of the accretion process, during which the shredded stellar debris orbits the black hole and is gradually consumed. 

Importantly, the researchers confirmed that these phenomena occurred in so-called inactive black holes—dormant ones that remain passive for millions of years until a star accidentally ventures too close. In contrast to active galaxies, where the black hole continuously accretes matter, the observed TDE cases represent one-time, violent awakenings of these cosmic giants. 

Source: Massachusetts Institute of Technology