Star screams as it's sucked into black hole

Posted by Kate Taylor

Astrophysicists have for the first time detected the X-ray 'scream' from a star as it's consumed by a supermassive black hole.

The Suzaku and XMM-Newton orbiting X-ray telescopes have picked up semi-regular blips in the light from a galaxy 3.9 billion light years away in the northern constellation of Draco.

"You can think of it as hearing the star scream as it gets devoured, if you like," says University of Michigan astronomy professor Jon Miller.

The blips, known as quasiperiodic oscillations, occurred every 200 seconds, but occasionally disappeared. Such signals have often been detected at smaller black holes and are  believed to emanate from material about to be sucked in.

"In order for the black hole to feed from a star that its gravity has broken apart, the remains of the star must form an accretion disk surrounding the black hole," says University of Michigan fellow Rubens Reis.

"The disk gets heated up and we can see emissions from the disk very close to the black hole in X-rays. As this matter is falling in, it gives a quasiperiodic wobble and that's the signal we detected."

The signal repeats at a characteristic frequency, which the scientists say would sound like an ultra-low D-sharp.

Scientists have never observed an event like this so far away.

"Our discovery opens the possibility of studying orbits close to black holes that are very distant, and it could make it possible to study general relativity under extreme settings," says Miller.