"There is a cloud of gas known as G2 that we expect to fall into the black hole early next year (as seen from here). It is a small cloud, but we are waiting for fireworks," says the chief researcher
About 2 million years ago, the enormous black hole at the center of the Milky Way galaxy erupted in such a powerful explosion that it illuminated a cloud of dust 200 light-years away. This was revealed by a team led by researchers from the University of Sydney.
The findings also confirm the fact that black holes can flash and go from maximum power to absolute silence in a short period of time in cosmic terms.
"For twenty years, astronomers suspected that a big eruption took place, but now we know when the sleeping dragon woke up, which was 4 million times the mass of the Sun, and breathed fire with 100 million times more power than it has today," says Prof. Joss Bland-Hawthorne from the School of Physics at the University of Sydney, the lead researcher on an article published in the Astrophysical Journal.
"We have long suspected that the center of our galaxy may have erupted randomly in the past. Our observations point to a "smoking gun," says Martin Rees, the Astronomer Royal who was one of the first scientists to hypothesize that the black hole at the center of the galaxy also provided fuel for quasars. The evidence comes from lace-like hydrogen filaments known as the Magellanic Stream. It trails behind the two companion galaxies of the Milky Way - the Large Magellanic Cloud and the Small Magellanic Cloud.
"Since 1996 we have been aware of a strange glow from the Magellanic Stream, but we did not understand the reason for its existence. Then, this year, I realized that it must be the sign - the fossil record - of a huge burst of energy from the massive black hole at the center of our galaxy."
The area around the supermassive black hole at the center of the galaxy and the black hole itself is called the Sagittarius A star. It emits radiation in the radio, infrared, ultraviolet, X-ray and gamma-ray ranges. Bursts of radiation arise when small clouds of gas fall into the hot disk of matter swirling around the black hole. In contrast to the current silence, evidence of violent events in the past is emerging.
"In particular, in 2010, NASA's Fermi satellite discovered two huge bubbles of hot gas rising above the center of the galaxy, covering almost a quarter of the sky," said Prof. Bland-Hawthorne.
Gas bubbles like those discovered by the Fermi satellite were seen in simulations performed at the University of California at Stena Cruz earlier this year. The simulations raise a controversial idea that the bubbles were caused by an explosion that occurred in the Sagittarius A region during the last two million years.
"When I saw the study, I realized that the same event could also explain the mysterious glow we saw in the Magellanic Stream." said.
"Together with Dr. Ralph Sutherland of the Mount Stromello Observatory and Dr. Phil Maloney of the University of Colorado, I calculated that to explain this glow it had to have occurred about two million years ago because the energy released and observed by the Stena Cruisers matches to our delight that of the Magellanic Stream .”
"The stars of the galaxy do not generate enough ultraviolet radiation to explain the glow, and neither did they in the past," said Dr. Maloney. "The center of the galaxy never produced stars at such a high rate, and there had to be another explanation."
Prof Bland-Hawthorne said: "In fact, the radiation from the stars is only about one percent of what is responsible for this type of radiation now or at any time in the past. The galaxy could never produce so much ultraviolet radiation that is responsible for this. So the only explanation is that the radiation had to be produced by our dragon - the massive black hole."
"The significant discovery is the realization that the black hole can turn on and off within a million years, very fast in this 14 billion year old universe."
"Could an explosion on a massive scale happen again?"
"Yes, absolutely. There are lots of stars and gas clouds that could fall into the hot disc around the black hole," says Prof. Bland-Hawthorne. "There is a cloud of gas known as G2 that we expect to fall into the black hole early next year (as seen from here). It is a small cloud but we are waiting for fireworks. Prof. Bland-Hawthorne is a fellow at the Australian Astronomical Observatory.
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Regarding the question why it is called a black hole, the answer is simple, the enormous force of attraction causes a distortion in time and space like a funnel at the bottom of which is a singular point and this is the hole in space time regarding the name black because all its attraction is so enormous that even light cannot escape from it. Since all the enormous attraction of a black hole works on its entire circumference, because it is a star with a huge mass, the entry of matter that is sucked into the event horizon is from every possible direction. Research to increase speed for moving between different bodies in space. It is known that there are other small black stars in our galaxy, but since there is no mass of gas and matter in their immediate vicinity that forms the absorption disk around the black hole, it is therefore difficult to discover them and they are only discovered in cases where bodies or mass pass near them.
The gravitational force of the black star depends on its mass and the absorption disk in which the event horizon exists is directly dependent on the size of the black hole and its mass, that is, the larger it is, the larger the absorption disk, Stephen Hawking proposed a theory in which a black star ends its life over the course of billions of years by saying that every time it ejects Matter into space is losing mass, this can be seen in the photographs of the jets of gas thrown to vast distances from the monstrous hole of M87
The big bang 14 million years ago is probably the result of the explosion of a white hole that grew and grew and grew for tens if not hundreds of billions of years... whoever thinks there was nothing before the big bang is naive
Why is it called a hole? After all, when it swallows a star, for example, there is an opposite eruption (quasar)? And where are all the black holes that are created in our galaxy? Why aren't stars attached to them? Is entry into the horizon of events in the black hole from both directions?
It is interesting to understand the effect of the event on life in DHA. Reassuring that he didn't destroy them..
A black target is constantly absorbing additional material and its mass is constantly increasing
What are the hypotheses regarding its behavior in the distant future in many billions of years?
There are opinions that a black hole ends its life, it explodes into a white hole in another universe (cosmic bodies of this type also have a lifespan), so theoretically, if it is possible to create an artificial black hole and change it to a white hole, is this a safe way to travel through the universe without the need for the speed of light ?
There is a radius around that body that if you cross it, the force of gravity no longer allows escape even at the speed of light. This is the event horizon. And of course on the contrary, outside the same radius, you can escape if the speed is high enough.
If we explain in a slightly different way - since the gravitational force depends not only on the mass but also on the radius of the body (ie the distance from its center), the statement that a black hole swallows everything is always conditional on the distance from its center.
Thanks for the enlightening explanation. So there is a problem with the explanation that is sometimes attached to the black hole phenomenon, tends
to write "nothing can escape its gravity", which is why its location appears as a black hole in scans.
So some do manage to escape - if something passes near it, it may be captured, but there is no 100% certainty that it will end up there.
The giant black hole probably devoured a star or a small black hole. What was not eaten gained tremendous speed and flew out. We'll wait and see what happens with the approaching cloud, but it won't be as dramatic as a star bite.
Is there a video of the golf stream?
The question is over.
The answer is simple. What goes in does not come out, but what almost goes in comes out with drums and dances.
Something is not clear to me and I would appreciate clarification. This whole story with the "event horizon" and that nothing can escape from a black hole... it was a mystery what happens in the end with everything that goes into it, but if it undergoes an explosion from time to time and releases matter and energy... no answer to the question was found??