MIT scientists discover 18 new black holes actively destroying stars

Astronomers from MIT have discovered 18 previously unknown black holes actively "tearing apart" and "devouring" stars. This finding is already reshaping our understanding of the Universe, doubling the number of tidal disruption events (TDE) observed in the local Universe. The discovery of these black holes will help astronomers more accurately estimate the number of similar events in the Universe and move closer to theoretical models.

Such stellar destruction, known as tidal disruption, occurs when a star gets too close to a black hole, and gravitational forces create colossal tidal forces within the star. As a result of this interaction, the star is stretched vertically and compressed horizontally, a process known as "spaghettification." The star's material forms a disk around the black hole, with part of it being consumed by the black hole, while another part is ejected in the form of jets, accelerating at speeds close to the speed of light.

It was previously believed that black holes could only tear apart and consume stars in galaxies that had recently undergone an active period of star formation. However, this research demonstrates that TDE processes can occur in a broader range of galaxies, which is crucial for explaining some extreme phenomena observed around black holes.

Erin Kara, an associate professor in MIT's Department of Physics, notes that scientists have proposed the most exotic ideas for explaining these mysteries for a long time, but now is the moment when we may obtain all the answers.

The MIT team started searching for new black holes tearing apart stars after detecting the closest TDE event to Earth in the galaxy NGC 7392, located approximately 137 million light-years away.

Scientists developed an algorithm that allowed them to detect bursts of radiation associated with TDE based on infrared data. Using this algorithm and data from NASA's NEOWISE satellite, astronomers identified spectra from over 1000 galaxies at a distance of 600 million light-years from Earth.

By analyzing these data and comparing them with the characteristics of TDE and other phenomena such as supernova flashes, scientists confirmed 18 cases of TDE events caused by the gravitational influence of black holes, leading to the demise of stars.

The research team also discovered that stellar disruption events occur not only in rare galaxies after the completion of star formation but also in other types of galaxies. Surprisingly, such events even occur in galaxies filled with dense dust clouds.

Adding 18 new TDE observations to previously known events of this kind allowed scientists to determine that galaxies experience similar events approximately once every 50,000 years, consistent with previous theoretical predictions. "This gives us confidence that we don't need exotic physics to explain what we see," concluded Kara.