Astronomers reveal violent flaring at centre of black hole

Astronomers have shown the violent flaring at the centre of a black hole using state-of-the-art cameras.

They used the technology to create a high-frame rate movie of a growing black hole system at a level of detail never seen before.

Led by the University of Southampton, they also uncovered new clues to understanding the immediate surroundings of these enigmatic objects.

Black holes can feed off a nearby star and create discs of material – accretion discs – such as gas, dust and other stellar debris that has come close to it but not quite fallen in.

Here, the effect of a black hole’s strong gravity and the material’s own magnetic field can cause rapidly changing levels of radiation to be emitted from the system as a whole.

This radiation was detected in visible light by the HiPERCAM instrument on the Gran Telescopio Canarias (La Palma, Canary Islands) and in X-rays by Nasa’s NICER observatory aboard the International Space Station.

The research published in Monthly Notices of the Royal Astronomical Society studied a black hole system called MAXI J1820+070, which was first discovered in early 2018.

It is about 10,000 light years away, in our own Milky Way.

Scientists say it has the mass of about seven suns, collapsed down to a region of space smaller than the City of London.

The distances of the systems usually make them too faint and small to see, but the HiPERCAM and NICER instruments let the researchers record “movies” of the changing light from the system at more than three hundred frames per second, capturing violent “crackling” and “flaring” of visible and X-ray light.

Lead author John Paice, a graduate student at the University of Southampton and the Inter-University Centre for Astronomy and Astrophysics in India, said: “The movie was made using real data, but slowed down to one tenth of actual speed to allow the most rapid flares to be discerned by the human eye.

“We can see how the material around the black hole is so bright, it’s outshining the star that it is consuming, and the fastest flickers last only a few milliseconds – that’s the output of a hundred suns and more being emitted in the blink of an eye.”

Researchers also found dips in X-ray levels are accompanied by a rise in visible light, and vice-versa.