The black holes, those deceptive singularities that are situated on the cliff of the known and the unknown, are surprised by their behavior. Because organizations like the Horizon Telescope Event have made it clear, there is a lot we do not know about the holes and, worse than that, we do not even know how much we know.
Now, scientists have observed a new phenomenon that adds to the mystique of the black hole: a black hole that spins rapidly and expels massive plasma.
The black hole in question is part of a binary pair called V404 Cygni. The black hole is eating his companion star, sucking his dough on his accretion disk, then expelling the material through two jets. This is not unusual for a black hole, although not all have airplanes. But what is unusual is the synchronization of the material ejected by the jets. More than a constant current, the material appears in spots.
V404 Cygni is about 8,000 light years away from Earth. It was first seen in 1989 when it expelled a huge explosion of material and high energy radiation. Then he fell latent for 26 years.
Then, in 2015, it emerged again and the satellite of the European Space Agency (ESA) INTEGRAL (Laboratorio de astrofísica de rayos gamma INTErnacional) was able to study it in gamma rays of high energy. It became the brightest object in the sky in gamma rays. Then, the scientist of the INTEGRAL project, Erik Kuulkers, said "The behavior of this source is extraordinary at this time, with shining bright reflections repeated at time scales of less than one hour, which is rarely seen in other systems of black holes."
It is useful to examine how black holes like this work. The massive gravity of the black hole removes the material from its star companion to its accretion disk. The accretion disk rotates, warming the material and causing it to "shine." Some of the materials never reach the black hole and are emitted through jets.
Progressing rapidly, and a new study based on data collected during the 2015 explosion by several observatories provides an explanation.
"During the explosion we observed the details of the jet emissions when the material is expelled at a very high speed from the proximity of the black hole"Says Simone Migliari, astrophysics of the ESA who is co-author of the document."We can see that the airplanes are firing in different directions within a time period of less than one hour, which means that the internal regions of the system are rotating quite fast. "
Yes, the black hole is eating his companion star, sucking the material on his accumulation disk. And yes, some of the disc materials are expelled into jets. But, according to the study, this only happens in the bursts because, for some reason, the black hole is poorly aligned with its own accretion disk.
"What is different from V404 Cygni is that we think that the material disk and the black hole are poorly aligned, "Says Associate Professor James Miller-Jones of the International Center for Radio Astronomy Research (ICRAR) at the University of Curtin, Australia, who is the main author of the new document.
"It seems that this causes the internal part of the disk to become dry as a spinner that slows down and that the fire stretches in different directions as it changes its orientation.. "
Hesitation means that the material does not fall into the black hole at a uniform pace. When there is an explosion, it means that a large amount of material has fallen into the hole in a short period of time. This increases the amount of accretion disk material causing a burst of energy.
INTEGRAL was an integral part of this study because he saw V404 Cygni for four weeks. Other observatories could only watch for a few hours. INTEGRAL's observations allowed scientists to find out about the mechanics of the black hole, its geometry and its energy levels, and establish the link between the input material and the output.
"With INTEGRAL, we could continue watching V404 Cygni continuously for four weeks, while other high-energy satellites could only take shorter photos"Says Erik Kuulkers, scientist of the INTEGRAL project at ESA.
"X-ray data to support a model where the internal part of the accretion disk is inclined with respect to the rest of the system, probably due to the inclination of the black hole relative to the accompanying star orbit."Explains Simone.
The question remains, why is it wrong?
There are only some preliminary conjectures about the cause of misalignment. Maybe it was a supernova.
Since the same black hole was created by a supernova, this initial blow may have caused the hole and the inner segment of its accretion disk to be misaligned. This is what the simulations show, anyway.
"The results would fit into a scenario, also studied in recent computational simulations, where accretion flow around the black hole and jets can rotate together"Kuulkers says.
"We have to wait for similar dynamics in any strongly accumulating black hole, the rotation will align with the gas that influences, and we will have to take into account the different angles of ray inclination when we interpret the observations of the black holes of the Universe. "