This is what it looks like when a black hole snacks on a star: Astronomers documented a fatal encounter between an unlucky star and an intermediate-mass black hole

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Analyzing observations of an X-ray flare and fitting the data with theoretical models, astronomers documented a fatal encounter between an unlucky star and a black hole.
While black holes and toddlers don't seem to have much in common, they are remarkably similar in one aspect: Both are messy eaters, generating ample evidence that a meal has taken place.

But whereas one might leave behind droppings of pasta or splatters of yogurt, the other creates an aftermath of mind-boggling proportions. When a black hole gobbles up a star, it produces what astronomers call a "tidal disruption event." The shredding of the hapless star is accompanied by an outburst of radiation that can outshine the combined light of every star in the black hole's host galaxy for months, even years.

In a paper published in The Astrophysical Journal, a team of astronomers led by Sixiang Wen, a postdoctoral research associate at the University of Arizona Steward Observatory, use the X-rays emitted by a tidal disruption event known as J2150 to make the first measurements of both the black hole's mass and spin. This black hole is of a particular type -- an intermediate-mass black hole -- which has long eluded observation.

"The fact that we were able to catch this black hole while it was devouring a star offers a remarkable opportunity to observe what otherwise would be invisible," said Ann Zabludoff, UArizona professor of astronomy and co-author on the paper. "Not only that, by analyzing the flare we were able to better understand this elusive category of black holes, which may well account for the majority of black holes in the centers of galaxies."

By re-analyzing the X-ray data used to observe the J2150 flare, and comparing it with sophisticated theoretical models, the authors showed that this flare did indeed originate from an encounter between an unlucky star and an intermediate-mass black hole. The intermediate black hole in question is of particularly low mass -- for a black hole, that is -- weighing in at roughly 10,000 times the mass of the sun.

"The X-ray emissions from the inner disk formed by the debris of the dead star made it possible for us to…
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