Chaotic accretion observed for the first time as supermassive black hole gulps down huge amount of matter

A team of astronomers reports having observed a gigantic mass of matter, swallowed directly by a black hole at a speed of nearly a third of the speed of light, a first detailed in the Monthly Notices of the Royal Astronomical Society.

Black holes are cosmic ogres, objects so massive that nothing escapes them. Matter, light, everything that comes a little too close inevitably ends in the siphon – what happens in there is still unknown. However, we can still observe what happens at the edge of the cosmic giants. Indeed, when active, black holes are surrounded by a disc of material falling into the black hole at speeds approaching 10% of the speed of light. A bit like water sucked into a siphon. Thus, the material – before disappearing – follows a circular path, traveling inward along rotating clouds. But not this time.

Some researchers believe that supermassive black holes could lead to what they call “chaotic accretion”. In other words, rather than following the circular path opened by clouds of rotating matter, a mass of matter could – under certain conditions – fall directly into a black hole at any angle. And that’s exactly what happened with PG1211 + 143, a very active black hole observed with the XMM-Newton X-ray space telescope.

Astronomers explain that they have recorded a mass of matter of the size of the Earth composed of iron, calcium, argon, sulfur and silicon, falling directly into the black hole without passing through the “rotation” area, all at about a third of the speed of light. As if this mass of matter had been sucked at once. “This may be the first direct evidence of chaotic accretion in an [active galactic core], where accretion disks are generally misaligned on the black hole,” reads the study. This mass of matter would then be composed of particles agglutinated following collisions in different misaligned rings, before falling into the black hole, in a loss of momentum.

“To see these chains of matter fall into the black hole, you just have to look in the line of sight,” says Gizmodo Ken Pounds, professor emeritus of physics at the University of Leicester in the UK. This is a rare opportunity. Unique, one could even say. This is why other observations of this type will be necessary to definitively confirm the theory of “chaotic accretion”.

Eddy Shan

Eddie, a passionate video-game player focuses mostly on tech and science related new for The Talking Democrat