Scientists have explained why the ejections of some giant black holes move at superluminal speeds - they "dance", swinging in different directions, according to an article published in the journal Astronomy & Astrophysics.
“We now have good reason to believe that the surface of the black hole's accretion disk behaves like the Sun - it consists of hot gas, in which various magnetic processes constantly occur, including reconnection of lines of force and flares. The global magnetic field of this disk drives the movement and shape of black hole emissions,”says Christian Fendt of the Institute for Radio Astronomy in Bonn, Germany.
Supermassive black holes exist at the center of almost every galaxy. Unlike black holes, which appear when stars collapse, their mass is several million times that of the Sun. They periodically absorb stars, other celestial bodies and gas and eject part of the captured matter in the form of jets - beams of heated plasma moving at near-light speed.
The first observations of such ejections indicated the impossible - the speed of movement of matter in different parts of the jets could change dramatically and sometimes exceeded the speed of light. This discovery has led scientists to wonder how such beams of matter arise and why they move in such a way that it seems like a violation of the laws of physics.
Fendt and his colleagues figured out how this happens by observing one of the largest and closest to us supermassive black holes, located in the galaxy M87 in the constellation Virgo. It is only 54 million light-years distant from us, making the jet of its black hole, discovered almost a hundred years ago, clearly visible even for the simplest telescopes.
The network of radio telescopes VLBA, which united dozens of the most powerful astronomical radio dishes, helped scientists to take pictures of the "legs" of the jet and get close to it at a distance about seven times smaller than the size of the solar system.
After analyzing hundreds of images, German astronomers found that the jet was "dancing" - its base was constantly swinging, and the streams of matter received additional acceleration under the influence of magnetic fields that existed a short distance from the event horizon of the black hole in the center of M87.
These fluctuations, as the scientists explain, made them believe that the flow is moving at a speed faster than light, since matter periodically turned out to be lined up not in a straight line, but twisted into a kind of spiral.
Promotional video:
The source of these fields, as the researchers suggest, is the so-called accretion disk - a "donut" of hot gas and ground matter of stars and planets, surrounding a black hole. In it, according to Fendt and his colleagues, there are powerful magnetic fields, the interaction of which affects the jet and even participates in its creation, "transferring" the point where the base of the black hole ejection is located.
All this, as scientists note, in some way makes the emissions of black holes and our Sun, flares and spots on the surface of which are born in a similar way. Is this really so, astronomers plan to check in the near future, when the participants of the Event Horizon Telescope project decipher more detailed images of the M87 core, obtained in early April.
