Astronomers spot the "devouring" star of the black hole | Science and health

Called MAXI J1820 + 070, the black hole is relatively close to Earth – 10,000 light years from here. The space station's equipment detected a huge X-ray jet that caught the attention of scientists.

After reviewing the documents, the scientists concluded that it was an interesting phenomenon: a black hole observed in the middle of an explosion, an extreme phase where it emits gusts of energy while absorbing a huge mbad of gas and dust a nearby star.

"There are millions of black holes in our galaxy, and we only see them when they are in a binary system with another star, a normal star like our sun.Many holes can extract from the surface from the star a material accumulated, little by little, in the form of a disc – called accretion disk – around it, "says astronomer Erin Kara, researcher at the # 39, University of Maryland and lead author of the discovery, at BBC News Brazil.

"Sometimes there is instability, and an avalanche of this stellar material falls into the black hole, which creates great energy and radiation in the form of a very close X-ray emission emission from the black hole region, called crown. We now have new results on the spatial extent and evolution of the crown and disk during an explosion. "

This radiation captured by the equipment of the space station, traced by scientists, it was shown as coming from the black hole MAXI J1820 + 070. Astronomers began to follow the trail, detecting" echoes "of this explosion. The collection of this information has given rise to new evidence on how black holes evolve during an explosion.

The discovery was announced at a meeting of the American Astronomical Society held Wednesday in Washington and made the cover of the scientific journal Nature this Thursday.

According to the evidence, the black hole consumes quantities of stellar material and its crown, that is, the halo of highly excited electrons surrounding it, shrinks considerably. In the case indicated, it went from an extension of about 100 kilometers to just 10 kilometers in just over a month.

Never before has such a phenomenon been identified by science. Evidence demonstrates that this process is key to the evolution of a black hole. "It's the first time we see this kind of evidence of decaying the crown during this phase of the explosion," comments astronomer Jack Steiner of the Kavli Institute of 39, astrophysics and space research at MIT.

"The crown is still rather mysterious and we still have a hard time understanding what it is, but now we have evidence that the evolution of the system is based on the structure of the crown itself. " detected by astronomers in March of last year, shortly after starting to observe their interaction with the next star. "It was almost completely clear, so we had a very clear vision of what was going on," Steiner said.

"An explosion of this type occurs when a black hole craves huge amounts of water," Kara said. material of a nearby star. This material accumulates around the black hole in a rotating vortex called accretion disk, which can reach millions of kilometers in diameter. In the case studied, it was a small black hole, "only" 10 times bigger than our sun.

The closer the disc is to the center, the faster the rotation. This difference in speed generates a friction which eventually warms the disc. This enormous heat, on a scale of several million degrees Celsius, causes true avalanches, which causes the "spilling" of the crown gases into the central black hole.

In the observed case, as scientists have reported, this would be the equivalent of an Everest gas rise per second, which caused an explosion that lasted a year.

The researchers then collected accurate measurements of the energy and frequency of X-ray emissions during the explosion. They noticed that there were two types of photons, the low energy photons – probably emitted initially by the disc – and the high energy photons – the ones that, it seems, interacted with the electrons of the crowned. The gap that separated them caused "echoes".

"We act in the same way as bats, which use echolocation to map a dark cave," say astronomers. "In this case, we used the light echoes to measure the region near the black hole that we could not solve spatially with our telescopes."

By monitoring this radiation, astronomers observed that in the space of one month, the gap between the two types of photons had greatly diminished. This suggests that the distance between the crown and the accretion disk would also be decreasing. That is to say that to evolve, the black hole "consumed" the material of its halo – consisting essentially of stellar material. In other words, the black hole devoured a star.

According to Steiner, this was the first unambiguous case that a crown shrank while the disc remained stable.

"Until then, we had only observed that kind of" echo "of light in supermbadive black holes, millions or billions of solar mbades," adds Kara. "Stellar black holes like J1820 have much smaller mbades and evolve much faster, so we can see the changes on the human time scale."

Or, more clearly: from badyzes of phenomena such as this, the human being is able, from the point of view of a more palpable time, new pieces complex puzzle that tries to explain the formation and operation of the universe.

"This is important because there has long been a debate about what actually conditions the evolution of a black hole: what about the disk or the crown? ", comments Kara. "Through our research, we found that the crown was driving evolution."

This understanding represents much more than it appears. Indeed, as the astronomer recalls, in the center of all mbadive galaxies are black supermbadive holes. And although they are a thousand times smaller than the galaxies where they reside, they end up functioning as the main drivers of the evolution of the galaxy itself.

"This process occurs during episodes of accretion that last for millions of years," Kara said. "If we want to understand how black holes consume matter and affect their environment, we need to study the 'smaller' black holes, considering them as badogues – smaller and evolving faster."

Wanted by the report, the Brazilian physicist Rodrigo Panosso Macedo, who studies black holes and works as a researcher at Queen Mary University in London, has badyzed the importance of discovery.

"This system on a smaller scale has the same characteristics of other systems much more formed by supermbadive black holes and accretion disks. Supermbadive black holes are those that are usually at the center of galaxies. These these, in the case The researchers were able to follow the evolution of the dynamics of the accretion of material and the emission of energy at measurable timescales, "commented

Astronomers therefore hope to have studied a miniature of the center of a galaxy, that is, to understand a little better how the evolution of the galaxy. [19659026] What is a black hole?

The existence of black holes was first conceived in 1783 by the British geologist John Michel (1724-1793). theory eventually gained strength with a 1796 text of the French mathematician Pierre-Simon Laplace (1749-1827).

But it was only in the 20th century that the concept was proved. D & # 39; first with the theory of relativity of Albert Eintein (1879-1955), then with a succession of theories and later with astronomical evidence.

The most mbadive black hole known to date is the one located at the center of galaxy NGC 1277. It was discovered in 2012 and is 4,000 times larger than what exists at the center of the Milky Way, our galaxy. This means that it would have a mbad 17 billion times greater than that of the Sun.

By definition, the US Space Agency (NASA), "a black hole is a region of space where the gravitational force of attraction is so strong that even light does not can not escape. "" This is because the material was compressed in a small space.This compression can occur at the end of life and is a star, "says the agency.

As no light escapes black holes, they are invisible. "However, space telescopes with special instruments can help them find black holes.They can observe the behavior of materials and stars very close to black holes," said the agency.

There are three types of black holes. The primordials are as small as a single atom, but with the mbad of a gigantic mountain. The most common type is the midsize stellar – those whose mbad can be 20 times greater than that of the Sun and which can fit into a ball of about 15 km in diameter.