A star in the act of being devoured by a supermassive black hole. It’s the latest incredible cosmic phenomenon tracked and traced by astronomers using giant telescopes.
This iconic “tidal disruption event”—named “AT2019qiz”—occurred 215 million light-years away, which makes it the closest observed so far.
“The idea of a black hole “sucking in” a nearby star sounds like science fiction, but this is exactly what happens in a tidal disruption event,” said Dr Matt Nicholl, a lecturer and Royal Astronomical Society research fellow at the University of Birmingham in the UK, and lead author of the paper published today in Monthly Notices of the Royal Astronomical Society.
“We were able to investigate in detail what happens when a star is eaten by such a monster,” he added.
What is a ‘tidal disruption event?’
It’s when a star gets too close to a black hole and thus gets pulled apart by the black hole’s extreme gravitational pull. “An unfortunate star in the nucleus of a galaxy can find itself on an orbit that intersects the tidal radius of the central supermassive black hole,” reads the paper. “This destruction can power a very luminous flare.” That’s exactly what the researchers saw.
What happened to the star?
It was shredded into a tube of material. The astronomical term used to describe it is “spaghettification.”
Under the extreme tidal forces of a black hole, stars can be vertically stretched and horizontally compressed into long thin streams of material. “The observations showed that the star had roughly the same mass as our own Sun, and that it lost about half of that to the black hole, which is over a million times more massive,” said Nicholl, who is also a visiting researcher at the University of Edinburgh in the UK.
Why is this such a rare sight for astronomers?
During the star’s “spaghettification” some of the material fell into the black hole and released a bright flare of energy. Astronomers detected that rare blast of light. It’s a sight described by the researchers as “faint and fast”—such events are usually obscured by a curtain of dust and debris, and it was only because it was detected just after the star was ripped apart that the flare could be detected.
“When a black hole devours a star, it