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Astronomers have discovered balanced jets coming from a black hole nearly 8000 light-years away from Earth.
Posted today in the journal Nature, research shows that V404 Cygni black hole jets behave like never before on such short periods.
The jets seem to spin quickly with high-speed plasma clouds, potentially a few minutes apart, firing from the black hole in different directions.
Lead author, James Miller-Jones, of the Curtin University node of the International Center for Research in Radioastronomy (ICRAR), said that black holes are among the most extreme objects in the universe.
"It's one of the most extraordinary black hole systems I have ever encountered," said Associate Professor Miller-Jones.
"Like many black holes, it feeds on a nearby star, moves the gas away from the star and forms a disc of matter that surrounds the black hole and that winds up under it. effect of gravity.
"What's different about V404 Cygni is that we think the material disc and the black hole are misaligned." This seems to make the inner part of the disc wobble like a top and project jets in different directions as the orientation changes. . "
The V404 Cygni was first identified as a black hole in 1989 when it triggered an explosion of jets and radiation.
Astronomers examining photographic plates of archives then discovered earlier explosions in observations of 1938 and 1956.
Associate Professor Miller-Jones said that when V404 Cygni experienced another very strong explosion in 2015, which lasted two weeks, telescopes from around the world listened to study what was going on.
"Everyone jumped on the explosion with every possible telescope," he said.
"So we have this incredible coverage."
When associate professor Miller-Jones and his team studied the black hole, they found that his jets behaved like never before.
Where it is generally thought that the jets exit directly from the poles of the black holes, these jets were firing in different directions and at different times.
And they changed direction very quickly – in less than two hours.
Associate Professor Miller-Jones said the change in jet movement was due to the accretion disk – the disc rotating the material around a black hole.
He pointed out that the accretion disk of the Cygni V404 was 10 million kilometers wide and that the few thousand internal kilometers were inflated and flickering during the explosion.
"The internal part of the accretion disk preceeded and effectively trained the jets," said associate professor Miller-Jones.
"You can think of this as a flicker of a spinning top that slows in. Only in this case, this flicker is caused by Einstein's theory of general relativity."
The research used observations from the Very Long Baseline Array, a continent-sized radio telescope of 10 satellite dishes distributed in the United States from the Caribbean Virgin Islands to Hawaii.
Co-author Alex Tetarenko – a recent Ph.D. graduate from the University of Alberta and currently a researcher at East Asian Observatory in Hawaii – said that the speed at which streams changed direction required scientists to use a very different approach from most radio observations.
"Typically, radio telescopes produce a single image after several hours of observation," she said.
"But these jets were changing so fast that in a four-hour picture we just saw a blur.
"It was like trying to take a picture of a waterfall with a shutter speed of a second." Instead, the researchers produced 103 individual images, each lasting about 70 seconds, and collected them in a film.
"It's only by doing this that we've been able to see these changes over a very short time," Dr. Tetarenko said.
The co-author of the study, Gemma Anderson, who is also based at the Curtin University node of ICRAR, said the wobbling of the internal accretion disk could also occur in D & D. Other extreme events of the universe.
"Whenever you get a misalignment between the rotation of a black hole and the material falling, you expect to see it when a black hole starts to feed very quickly," said Dr. Anderson. .
"This could include a whole series of brilliant and explosive events in the universe, such as supermassive black holes feeding very fast or tidal disturbances, when a black hole tears a star."
Video: https://vimeo.com/332582739
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