Astronomers have recently been able to film a black hole siphoning off the matter from its neighboring star, which has been reconstructed from real data, to help us better understand these enigmatic objects.
Black holes, there are all kinds. Big, small, solitary, and others in couple. The latter are the easiest to observe to the extent that they can, sometimes, begin to siphon the matter of the star that accompanies them. The heat generated then emits a significant light that can be seen by our larger telescopes.
This is what has recently happened about 10,000 light-years away from Earth. Researchers at the University of Southampton have in fact pointed the ultramodern cameras of the Gran Telescopio Canarias (La Palma, Canary Islands) and NASA’s NICER observatory aboard the ISS, on the binary torque MAXI J1820 + 070. These two objects – a black hole and a star – have been known for a few months.
Small but greedy
The black hole of this cosmic duo is not very big. It is about seven times heavier than the Sun, and collapsed in a region smaller than the city of Paris. But he is a gourmand. Witness the very large accretion disk that surrounds it, a sign that he is stealing matter from his star.
Thanks to the images collected by the two telescopes (300 per second), the researchers were able to recreate a film of this event, revealing the crackles and splinters of visible light and X-rays.
The film was made with real data, but slowed down to 1/10 the actual speed to allow the human eye to discern the fastest flashes, says John Paice, lead author of the study. Here the fastest glitters only last a few milliseconds. They are also brighter than a hundred suns together.
These data, very valuable, allowed the researchers to truly break down the course of this event. For example, they found that the hollows in X-rays were accompanied by an increase in visible light (and vice versa). And that the fastest flashes in visible light appeared a fraction of a second after X-rays.
For researchers, these behaviors reveal to us, indirectly, the presence of plasma, an extremely hot material within which all electrons have been removed from their atom.
