Astronomers observe a black hole engulfing and tearing apart a star

It is the most distant black hole of this type yet detected, whose plasma jet is visible because it points towards Earth.

Several teams of astronomers have detected a rare tidal disruption event (TDE), which occurs when a star is torn apart by a supermassive black hole and releases a series of bursts of energy, according to two published papers. this Wednesday in the journals Nature and Nature Astronomy. The findings may improve our understanding of the properties of black holes at cosmological distances.

Stars too close to a black hole are torn apart by the black hole’s incredible tidal forces. About 1% of these events cause jets of plasma and radiation to be ejected from the poles of the spinning black hole. In 1971, black hole pioneer John Wheeler introduced the jet TDE concept as “a tube of toothpaste that is squeezed hard from the middle” causing the system to “expel matter from both ends”.

TDEs may provide an opportunity to study how supermassive black holes grow by accreting (or accreting) matter. When a star is rapidly pulled into a black hole, it can break apart and its material can fall onto the black hole’s accretion disk. In some cases, the accumulated material generates powerful jets of matter, and in very rare cases, TDEs can lead to the production of a relativistic jet, traveling close to the speed of light, but these events are rare and poorly understood.

Igor Andreoni, Michael Coughlin and his team on the one hand, and Dheeraj R. Pasham and his colleagues on the other, report the detection of AT2022cmc: a transient astronomical event that releases large amounts of energy. The observations, made in the optical range and at other wavelengths using multiple telescopes, are consistent with the emission of a luminous jet from the violent disruption of a star passing too close to a massive black hole.

These observations, particularly those in the X-ray regime, indicate the extreme energies involved, and the rapid changes in brightness and long-duration nature of the entire event are characteristic of a rare relativistic jet TDE, one of only four reported. till the date. While most detected TDEs originate from the nearby Universe, this event came from a galaxy at a distance of about 12,400 light-years, visible from Earth because of its exceptional brightness. “We’ve only seen a handful of these jetted TDEs and they’re still very exotic and little-known events,” says Nial Tanvir of the University of Leicester in the UK, who led the VLT observations to determine the object’s distance.

References: A very luminous jet from the disruption of a star by a massive black hole (Nature) doi: 10.1038/s41586-022-05465-8 | The Birth of a Relativistic Jet Following the Disruption of a Star by a Cosmological Black Hole (Nature Astronomy) doi: 10.1038/s41550-022-01820-x | Source: IT