A black hole is a region in space-time whose gravitational pull is so strong that not even light can escape. Black holes that have grown to gigantic sizes form the cores of most galaxies.

A supermassive black hole is a black hole with a mass of about 10 5 -10 10 solar masses. As of 2014, supermassive black holes have been discovered at the center of many galaxies, including our Milky Way.

1. The heaviest supermassive black hole outside our galaxy is located in a galaxy in the giant elliptical galaxy NGC 4889 in the constellation Coma Berenices. Its mass is about 21 billion solar masses!

In this image, the galaxy NGC 4889 is in the center. Somewhere there was that same giant lurking. (NASA Photo):

2. There is no generally accepted theory of the formation of black holes of such mass. There are several hypotheses, the most obvious of which is the hypothesis that describes the gradual increase in the mass of a black hole through the gravitational attraction of matter (usually gas) from the surrounding space. The difficulty of forming a supermassive black hole is that a sufficient amount of matter must be concentrated in a relatively small volume.

An artist's impression of a supermassive black hole and its accretion disk. (NASA Photo):

3. Spiral galaxy NGC 4845 (type Sa) in the constellation Virgo, located at a distance of 65 million light years from Earth. At the center of the galaxy is a supermassive black hole with a mass of about 230,000 solar masses. (NASA Photo):

4. The Chandra X-ray Observatory (NASA) recently provided evidence that many supermassive black holes rotate at enormous speeds. The measured rotation speed of one of the black holes is 3.5 trillion. miles/hour is about half the speed of light, and its incredible gravity pulls the surrounding space for many millions of kilometers. (NASA Photo):

5. Spiral galaxy NGC 1097 in the constellation Fornax. At the center of the galaxy is a supermassive black hole that is 100 million times heavier than our Sun. It sucks into itself any matter in the area. (NASA Photo):

6. The most powerful quasar in the Markarian 231 galaxy can receive energy from two centrally located black holes that circle each other. According to scientists' calculations, the mass of the central black hole exceeds the solar mass by 150 million times, and the mass of the satellite black hole exceeds the solar mass by 4 million times. This dynamic duo consumes galactic matter and produces enormous amounts of energy, causing a halo at the center of the galaxy that can outshine billions of stars.

Quasars are the brightest sources in the Universe, the light of which is brighter than the glow of their galaxies. There is a hypothesis that quasars are the nuclei of distant galaxies at a stage of unusually high activity. The quasar in the center of the Markarian 231 galaxy is the closest such object to us and manifests itself as a compact radio source. Scientists estimate its age at only a million years. (NASA Photo):

7. Giant elliptical galaxy M60 and spiral galaxy NGC 4647 look very strange couple. They are both located in the constellation Virgo. Bright M60, located about 54 million light-years away, has simple form an egg that is created by randomly swarming old stars. NGC 4647 (top right), on the other hand, is composed of young blue stars, gas and dust, all arranged in the swirling arms of a flat, rotating disk.

At the center of M60 is a supermassive black hole with 4.5 billion solar masses. (NASA Photo):

8. Galaxy 4C+29.30, located at a distance of 850 million light years from Earth. At the center is a supermassive black hole. Its mass is 100 million times greater than the mass of our Sun. (NASA Photo):

9. Astronomers have long been looking for confirmation that Sagittarius A is our supermassive black hole at the center milky way, is the source of the plasma jet. Finally, they found it, according to new results obtained by the Chandra X-ray Observatory and the VLA radio telescope. This jet, or jet, is formed by the absorption of matter by a supermassive black hole and its existence has long been predicted by theorists. (NASA Photo):

10. Using the highest quality X-ray images, astronomers have found the first clear evidence that massive black holes were similar in the Early Universe. Studies and observations of distant galaxies have shown that they all have similar supermassive black holes. At least 30 million supermassive black holes have been found in the Early Universe. This is 10,000 times more than previously estimated.

The artist's drawing shows a growing supermassive black hole. (NASA Photo):

11. Barred spiral galaxy NGC 4945 (SBc) in the constellation Centaurus. It is quite similar to our Galaxy, but X-ray observations indicate the presence of a core likely containing an active supermassive star. black hole. (NASA Photo):

12. Cluster PKS 0745-19. The black hole at the center is one of the 18 largest known black holes in the Universe. (NASA Photo):

13. A powerful stream of particles from a supermassive black hole hitting a nearby galaxy. Astronomers have observed galaxy collisions before, but this is the first time such a “space shot” has been recorded. The “incident” occurred in a star system located 1.4 billion light years from Earth, where two galaxies are currently merging. The “black hole” of the larger of the two galaxies, which astronomers compare to the “Death Star” from the film epic “Star Wars,” ejected a powerful stream of charged particles that landed directly in the galaxy next door. (NASA Photo):

14. The youngest black hole was found. The progenitor of the newcomer was a supernova that erupted just 31 years ago. (Photo by Chandra X-ray Observatory Center):

15. Artistic depiction black hole swallowing outer space. Since the theoretical prediction of black holes, there has remained open question about their existence, since the presence of a “black hole” type solution does not guarantee that there are formation mechanisms similar objects in the Universe. (NASA Photo):

16. Black hole flares in spiral galaxy M83 (also known as the Southern Pinwheel) captured by NASA's Chandra X-ray Observatory. South Pinwheel is approximately 15 million light years away. (NASA Photo):

17. Barred spiral galaxy NGC 4639 in the constellation Virgo. NGC 4639 hides a massive black hole that is swallowing cosmic gas and dust. (NASA Photo):

18. Galaxy M 77 in the constellation Cetus. At its center is a supermassive black hole. (NASA Photo):

19. Artists depicted the black hole of our Galaxy – Sagittarius A*. This is an object of enormous mass. By analyzing the orbital elements, it was initially determined that the weight of the object is 2.6 million solar masses, and this mass is contained in a volume of no more than 17 light hours (120 au) in diameter. (NASA Photo):

20. Look into the mouth of a black hole. Astronomers from the Japanese aerospace agency JAXA managed to obtain a unique image of the mouth of a black hole and rare phenomena in its vicinity using NASA's WISE infrared space laboratory. The object observed by WISE was a black hole 6 times the mass of the sun and cataloged as GX 339-4. Near GX 339-4, located at a distance of more than 20 thousand light years from Earth, there is a star, the matter of which is drawn into the black hole under the influence of its monstrous gravitational field, which is 30 thousand times stronger than on the surface of our planet. In this case, part of this matter is ejected from the black hole in the opposite direction, forming jets of particles moving at near-light speeds. (NASA Photo):

21. Galaxy NGC 3081 in the constellation Hydra. It is located at a distance of about 86 million light years from the Solar System. Scientists believe that at the center of NGC 3081 there is a supermassive black hole. (NASA Photo):

22. Sleeps and dreams. Nearly a decade ago, NASA's Chandra X-ray Observatory detected evidence of what appeared to be a black hole consuming gas right at the center of the nearby Sculptor galaxy. And in 2013, NASA's NuSTAR space telescope, which detects hard X-rays, takes a quick look in the same direction and discovers a peacefully sleeping black hole (it has become inactive over the past 10 years).

The mass of a dormant black hole is about 5 million times the mass of our Sun. The black hole is located at the center of the Sculptor galaxy, also known as NGC 253. (NASA Photo):

23. Plasma ejected by supermassive black holes at the centers of galaxies can transfer enormous amounts of energy over gigantic distances. Region 3C353, seen in X-ray light from the Chandra and Very Large Array telescopes, is surrounded by plasma ejected from one of the black holes. Against the background of giant “feathers”, the galaxy’s radiation appears as tiny dots in the center. (NASA Photo):

24. According to the artist, this is what a supermassive black hole with a mass of several million to billions times the mass of our Sun might look like. The difficulty of forming a supermassive black hole is that a sufficient amount of matter must be concentrated in a relatively small volume. (NASA Photo).

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Consider the mysterious and invisible black holes in the Universe: interesting facts, Einstein's research, supermassive and intermediate types, theory, structure.

- one of the most interesting and mysterious objects in outer space. Possess high density, and the gravitational force is so powerful that even light cannot escape beyond its limits.

Albert Einstein first spoke about black holes in 1916, when he created the general theory of relativity. The term itself originated in 1967 thanks to John Wheeler. And the first black hole was “seen” in 1971.

The classification of black holes includes three types: stellar mass black holes, supermassive black holes and black holes. average weight. Be sure to watch the video about black holes to learn many interesting facts and get to know these mysterious cosmic formations better.

Interesting facts about black holes

• If you find yourself inside a black hole, gravity will stretch you. But there is no need to be afraid, because you will die before you reach the singularity. A 2012 study suggested that quantum effects turn the event horizon into a wall of fire that turns you into a pile of ash.
• Black holes don't "suck". This process is caused by a vacuum, which is not present in this formation. So the material just falls off.
• The first black hole was Cygnus X-1, found by rockets with Geiger counters. In 1971, scientists received a radio signal from Cygnus X-1. This object became the subject of a dispute between Kip Thorne and Stephen Hawking. The latter believed that it was not a black hole. In 1990, he admitted defeat.
• Tiny black holes may have appeared immediately after the Big Bang. Rapidly rotating space compressed some areas into dense holes, less massive than the Sun.
• If the star gets too close, it could be torn apart.
• It is generally estimated that there are up to a billion stellar black holes with three times the mass of the Sun.
• If we compare string theory and classical mechanics, the former gives rise to more varieties of massive giants.

The danger of black holes

When a star runs out of fuel, it can begin the process of self-destruction. If its mass was three times that of the Sun, then the remaining core would become a neutron star or a white dwarf. But the larger star transforms into a black hole.

Such objects are small, but have incredible density. Imagine that in front of you is an object the size of a city, but its mass is three times that of the Sun. This creates an incredibly huge gravitational force that attracts dust and gas, increasing its size. You will be surprised, but there may be several hundred million stellar black holes.

Supermassive black holes

Of course, nothing in the universe compares to the awesomeness of supermassive black holes. They exceed the solar mass by billions of times. It is believed that such objects exist in almost every galaxy. Scientists do not yet know all the intricacies of the formation process. Most likely, they grow due to the accumulation of mass from surrounding dust and gas.

They may owe their scale to the merger of thousands of small black holes. Or an entire star cluster could collapse.

Black holes at the centers of galaxies

Astrophysicist Olga Silchenko about the discovery of a supermassive black hole in the Andromeda nebula, John Kormendy's research and dark gravitating bodies:

The nature of cosmic radio sources

Astrophysicist Anatoly Zasov about synchrotron radiation, black holes in the nuclei of distant galaxies and neutral gas:

Intermediate black holes

Not long ago, scientists found new look- black holes of average mass (intermediate). They can form when stars in a cluster collide, causing a chain reaction. As a result, they fall into the center and form a supermassive black hole.

In 2014, astronomers discovered an intermediate type in the arm of a spiral galaxy. They are very difficult to find because they can be located in unpredictable places.

Micro black holes

Physicist Eduard Boos on the safety of the LHC, the birth of a microblack hole and the concept of a membrane:

Black hole theory

Black holes are extremely massive objects, but span a relatively modest amount of space. In addition, they have enormous gravity, preventing objects (and even light) from leaving their territory. However, it is impossible to see them directly. Researchers have to look at the radiation produced when a black hole feeds.

Interestingly, it happens that matter heading towards a black hole bounces off the event horizon and is thrown out. In this case, bright jets of material are formed, moving at relativistic speeds. These emissions can be detected over long distances.

- amazing objects in which the force of gravity is so enormous that it can bend light, warp space and distort time.

In black holes, three layers can be distinguished: the outer and inner event horizon and the singularity.

The event horizon of a black hole is the boundary where light has no chance of escaping. Once a particle crosses this line, it will not be able to leave. The inner region where the mass of a black hole is located is called a singularity.

If we speak from the position of classical mechanics, then nothing can escape a black hole. But quantum makes its own correction. The fact is that every particle has an antiparticle. They have the same masses, but different charges. If they intersect, they can annihilate each other.

When such a pair appears outside the event horizon, one of them can be pulled in and the other can be repelled. Because of this, the horizon can shrink and the black hole can collapse. Scientists are still trying to study this mechanism.

Accretion

Astrophysicist Sergei Popov on supermassive black holes, planet formation and accretion of matter in the early Universe:

The most famous black holes

Frequently asked questions about black holes

More capaciously, a black hole is a certain area in space in which such a huge amount of mass is concentrated that not a single object can escape the gravitational influence. When it comes to gravity, we rely on the general theory of relativity proposed by Albert Einstein. To understand the details of the object under study, we will move step by step.

Let's imagine that you are on the surface of the planet and are throwing a boulder. If you don't have the power of the Hulk, you won't be able to exert enough force. Then the stone will rise to a certain height, but under the pressure of gravity it will fall back. If you have the hidden potential of a green strongman, then you are able to give the object sufficient acceleration, thanks to which it will completely leave the zone of gravitational influence. This is called "escape velocity".

If we break it down into a formula, then this speed depends on planetary mass. The larger it is, the more powerful the gravitational grip. The speed of departure will depend on where exactly you are: the closer to the center, the easier it is to get out. The speed of departure of our planet is 11.2 km/s, but it is 2.4 km/s.

We are getting closer to the most interesting part. Let's say you have an object with an incredible concentration of mass collected in a tiny place. In this case, the escape velocity exceeds the speed of light. And we know that nothing moves faster than this indicator, which means that no one will be able to overcome such force and escape. Even a light beam cannot do this!

Back in the 18th century, Laplace pondered the extreme concentration of mass. Following general relativity, Karl Schwarzschild was able to find a mathematical solution to the theory's equation to describe such an object. Further contributions were made by Oppenheimer, Wolkoff and Snyder (1930s). From that moment on, people began to discuss this topic seriously. It became clear: when a massive star runs out of fuel, it is unable to withstand the force of gravity and is bound to collapse into a black hole.

In Einstein's theory, gravity is a manifestation of curvature in space and time. The fact is that the usual geometric rules do not work here and massive objects distort space-time. The black hole has bizarre properties, so its distortion is most clearly visible. For example, an object has an “event horizon.” This is the surface of the sphere marking the line of the hole. That is, if you step over this limit, then there is no turning back.

Literally, this is the place where the escape speed is equal to the speed of light. Outside this place, the escape velocity is inferior to the speed of light. But if your rocket is able to accelerate, then there will be enough energy to escape.

The horizon itself is quite strange in terms of geometry. If you are far away, you will feel like you are looking at a static surface. But if you get closer, you realize that it is moving outward at the speed of light! Now I understand why it is easy to enter, but so difficult to escape. Yes, this is very confusing, because in fact the horizon stands still, but at the same time it rushes at the speed of light. It's like the situation with Alice, who had to run as fast as possible just to stay in place.

When hitting the horizon, space and time experience such a strong distortion that the coordinates begin to describe the roles of radial distance and switching time. That is, “r”, marking the distance from the center, becomes temporary, and “t” is now responsible for “spatiality”. As a result, you will not be able to stop moving with a lower index of r, just as you will not be able to get into the future in normal time. You will come to a singularity where r = 0. You can throw rockets, run the engine to maximum, but you cannot escape.

The term "black hole" was coined by John Archibald Wheeler. Before that, they were called “cooled stars.”

Physicist Emil Akhmedov on the study of black holes, Karl Schwarzschild and giant black holes:

There are two ways to calculate how big something is. You can name the mass or how large the area occupies. If we take the first criterion, then there is no specific limit on the massiveness of a black hole. You can use any amount as long as you can compress it to the required density.

Most of these formations appeared after the death of massive stars, so one would expect that their weight should be equivalent. The typical mass for such a hole would be 10 times that of the sun - 10 31 kg. In addition, each galaxy must be home to a central supermassive black hole, whose mass exceeds the solar one a million times - 10 36 kg.

The more massive the object, the more mass it covers. The horizon radius and mass are directly proportional, that is, if a black hole weighs 10 times more than another, then its radius is 10 times larger. The radius of a hole with solar massiveness is 3 km, and if it is a million times larger, then 3 million km. These seem to be incredibly massive things. But let's not forget that for astronomy this is standard concepts. The solar radius reaches 700,000 km, and that of a black hole is 4 times larger.

Let's say that you are unlucky and your ship is inexorably moving towards a supermassive black hole. There's no point in fighting. You simply turn off the engines and head towards the inevitable. What to expect?

Let's start with weightlessness. You are in free fall, so the crew, the ship and all the parts are weightless. The closer you get to the center of the hole, the stronger the tidal gravitational forces are felt. For example, your feet are closer to the center than your head. Then you begin to feel like you are being stretched. As a result, you will simply be torn apart.

These forces are unnoticeable until you get within 600,000 km of the center. This is already after the horizon. But we are talking about a huge object. If you fall into a hole with the mass of the sun, then the tidal forces would engulf you 6000 km from the center and tear you apart before you reach the horizon (that's why we send you to the big one so that you can die already inside the hole, and not on the approach) .

What's inside? I don't want to disappoint, but nothing remarkable. Some objects may be distorted in appearance and nothing else out of the ordinary. Even after crossing the horizon, you will see things around you as they move with you.

How long will all this take? Everything depends on your distance. For example, you started from a point of rest where the singularity is 10 times the radius of the hole. It will take only 8 minutes to approach the horizon, and then another 7 seconds to enter the singularity. If you fall into a small black hole, everything will happen faster.

As soon as you cross the horizon, you can shoot rockets, scream and cry. You have 7 seconds to do all this until you get into the singularity. But nothing will save you. So just enjoy the ride.

Let's say you are doomed and fall into a hole, and your boyfriend watches from afar. Well, he'll see things differently. You will notice that you slow down as you get closer to the horizon. But even if a person sits for a hundred years, he will not wait until you reach the horizon.

Let's try to explain. The black hole could have emerged from a collapsing star. Since the material is destroyed, Kirill (let him be your friend) sees it decreasing, but will never notice it approaching the horizon. That's why they were called "frozen stars" because they seem to freeze at a certain radius.

What's the matter? Let's call it an optical illusion. Infinity is not needed to form a hole, just as it is not necessary to cross the horizon. As you approach, the light takes longer to reach Kirill. More precisely, the real-time radiation from your transition will be recorded at the horizon forever. You have long stepped over the line, and Kirill is still observing the light signal.

Or you can approach from the other side. Time drags longer near the horizon. For example, you have a super-powerful ship. You managed to get closer to the horizon, stay there for a couple of minutes and get out alive to Kirill. Who will you see? Old man! After all, time passed much slower for you.

What is true then? Illusion or game of time? It all depends on the coordinate system used when describing a black hole. If you rely on Schwarzschild coordinates, then when crossing the horizon, the time coordinate (t) is equated to infinity. But the system's metrics provide a blurred view of what's happening near the object itself. At the horizon line, all coordinates are distorted (singularity). But you can use both coordinate systems, so the two answers are valid.

In reality, you will simply become invisible, and Kirill will stop seeing you before much time has passed. Don't forget about redshift. You emit observable light at a certain wavelength, but Kirill will see it at a longer one. The waves lengthen as they approach the horizon. In addition, do not forget that radiation occurs in certain photons.

For example, at the moment of transition you will send the last photon. It will reach Kirill at a certain finite time (about an hour for a supermassive black hole).

Of course not. Don't forget about the existence of the event horizon. This is the only area you can't get out of. It is enough just not to approach her and feel calm. Moreover, from a safe distance this object will seem very ordinary to you.

Hawking's information paradox

Physicist Emil Akhmedov on the effect of gravity on electromagnetic waves, the information paradox of black holes and the principle of predictability in science:

Don't panic, as the Sun will never transform into such an object because it simply doesn't have enough mass. Moreover, it will retain its current appearance another 5 billion years. Then it will move to the red giant stage, absorbing Mercury, Venus and thoroughly frying our planet, and then become an ordinary white dwarf.

But let's indulge in fantasy. So the Sun became a black hole. To begin with, we will immediately be enveloped in darkness and cold. The Earth and other planets will not be sucked into the hole. They will continue to orbit the new object in normal orbits. Why? Because the horizon will reach only 3 km, and gravity will not be able to do anything to us.

Yes. Naturally, we cannot rely on visible observation, since the light cannot escape. But there is circumstantial evidence. For example, you see an area that could contain a black hole. How can I check this? Start by measuring the mass. If it is clear that in one area there is too much of it or it is seemingly invisible, then you are on the right track. There are two search points: the galactic center and binary systems with X-ray radiation.

Thus, massive central objects were found in 8 galaxies, whose nuclear mass ranges from a million to a billion solar. Mass is calculated by observing the speed of rotation of stars and gas around the center. The faster, the greater the mass must be to keep them in orbit.

These massive objects are considered black holes for two reasons. Well, there are simply no more options. There is nothing more massive, darker and more compact. In addition, there is a theory that all active and large galaxies have such a monster hiding in the center. But still this is not 100% proof.

But two recent findings speak in favor of the theory. A “water maser” system was spotted near the nearest active galaxy ( powerful source microwave radiation) near the nucleus. Using an interferometer, scientists mapped the distribution of gas velocities. That is, they measured the speed within half a light year at the galactic center. This helped them understand that there was a massive object inside, whose radius reached half a light year.

The second find is even more convincing. Researchers using X-rays stumbled upon a spectral line of the galactic core, indicating the presence of atoms nearby, the speed of which is incredibly high (1/3 the speed of light). In addition, the emission corresponded to a redshift that corresponds to the horizon of the black hole.

Another class can be found in the Milky Way. These are stellar black holes that form after a supernova explosion. If they existed separately, then even close up we would hardly notice it. But we are lucky, because most exist in dual systems. They are easy to find, since the black hole will pull the mass of its neighbor and influence it with gravity. The “pulled out” material forms an accretion disk, in which everything heats up and therefore creates strong radiation.

Let's assume you managed to find a binary system. How do you understand that a compact object is a black hole? Again we turn to the masses. To do this, measure orbital speed neighboring star. If the mass is incredibly huge with such small dimensions, then there are no more options left.

This is a complex mechanism. Stephen Hawking raised a similar topic back in the 1970s. He said that black holes are not really “black.” There are quantum mechanical effects that cause it to create radiation. Gradually the hole begins to shrink. The rate of radiation increases with decreasing mass, so the hole emits more and more and accelerates the process of contraction until it dissolves.

However, this is only a theoretical scheme, because no one can say exactly what happens at the last stage. Some people think that a small but stable trace remains. Modern theories We haven't come up with anything better yet. But the process itself is incredible and complex. It is necessary to calculate parameters in curved space-time, and the results themselves cannot be verified under normal conditions.

The Law of Conservation of Energy can be used here, but only for short durations. The universe can create energy and mass from scratch, but they must quickly disappear. One of the manifestations is vacuum fluctuations. Pairs of particles and antiparticles grow out of nowhere, exist for a certain short period of time and die in mutual destruction. When they appear, the energy balance is disrupted, but everything is restored after disappearance. It seems fantastic, but this mechanism has been confirmed experimentally.

Let's say one of the vacuum fluctuations acts near the horizon of a black hole. Perhaps one of the particles falls in, and the second runs away. The one who escapes takes some of the energy of the hole with her and can fall into the eyes of the observer. It will seem to him that a dark object has simply released a particle. But the process repeats itself, and we see a continuous stream of radiation from the black hole.

We've already said that Kirill feels like you need infinity to step over the horizon line. In addition, it was mentioned that black holes evaporate after a finite period of time. So, when you reach the horizon, the hole will disappear?

No. When we described Kirill's observations, we did not talk about the evaporation process. But, if this process is present, then everything changes. Your friend will see you flying across the horizon at the exact moment of evaporation. Why?

An optical illusion dominates Kirill. The emitted light in the event horizon takes a long time to reach its friend. If the hole lasts forever, then the light can travel indefinitely, and Kirill will not wait for the transition. But, if the hole has evaporated, then nothing will stop the light, and it will reach the guy at the moment of the explosion of radiation. But you don’t care anymore, because you died in the singularity long ago.

In the formulas of general relativity there are interesting feature– symmetry in time. For example, in any equation you can imagine that time flows backwards and get a different, but still correct, solution. If we apply this principle to black holes, then a white hole is born.

A black hole is a defined area from which nothing can escape. But the second option is a white hole into which nothing can fall. In fact, she pushes everything away. Although, from a mathematical point of view, everything looks smooth, this does not prove their existence in nature. Most likely, there are none, and there is no way to find out.

Up to this point we have talked about the classics of black holes. They do not rotate and have no electrical charge. But in the opposite version, the most interesting thing begins. For example, you can get inside but avoid the singularity. Moreover, its “inside” is capable of contacting a white hole. That is, you will find yourself in a kind of tunnel, where the black hole is the entrance and the white hole is the exit. This combination is called a wormhole.

Interestingly, a white hole can be located anywhere, even in another Universe. If we know how to control such wormholes, then we will provide rapid transportation to any area of ​​​​space. And even cooler is the possibility of time travel.

But don't pack your backpack until you know a few things. Unfortunately, there is a high probability that there are no such formations. We have already said that white holes are a conclusion from mathematical formulas, and not a real and confirmed object. And all observed black holes create matter falling and do not form wormholes. And the final stop is the singularity.

Cosmonautics,

Physics,

Astronomy

On Wednesday night, 120 astronomers from eight observatories on four continents began the first attempt to photograph a black hole. Filming began on April 5 and will continue until April 14 this year. The object of observation was the vicinity of two supermassive black holes, one in the center of our Milky Way, the other in the neighboring galaxy Messier 87. The first is close, but small in diameter, the second is very far away, but huge. Which one will be seen better is still a question. The closest one to us, Sagittarius A*, is located in the center of our Milky Way galaxy at a distance of 26 thousand light years. The distant one is 6 billion times larger than the mass of our star, so the event horizon around it is larger. Sagittarius A* has a mass 1.5 thousand times smaller and fits in a space smaller than the volume inside the orbit of Mercury.

The importance of the observation is explained by Gopal Narayanan, research professor of astronomy at the University of Massachusetts Amherst: “At the heart of Einstein’s general theory of relativity is the idea that quantum mechanics and general relativity can be unified, that there is a grand, unified theory of fundamental concepts. The event horizon of a black hole is exactly where this possible association is best studied." We will only know the results in 2018, when computers process the data. At the end of the post there is a supposed image that we should see if Einstein's theory is correct.

To observe event horizons from disparate radio telescopes looking at each different part of the sky, astronomers have created a virtual radio telescope the size of Earth. 8 observatories in 6 territorial locations are conducting surveys.


The project involves the Massachusetts Institute of Technology Observatory (lead organization), the Harvard-Smithsonian Center for Astrophysics, the Joint ALMA Observatory (Chile), the National Radio Astronomy Observatory (NRAO), the Institute of Radio Astronomy. Max Planck University (Germany), University of Concepción (Chile), Institute of Astronomy and Astrophysics of the Central Academy of Taiwan (ASIAA, Taiwan), National Astronomical Observatory of Japan (NAOJ) and Onsala Observatory (Sweden). The combination of radio telescopes is important for observing fast processes in the Universe, which include, for example, supernova explosions and streams of cosmic radiation, as well as for detailed studies of small distant cosmic objects, such as the black hole Sagittarius A*. The most powerful optical telescopes are limited in their ability to observe even the most massive objects, and black holes are extremely compact.

By linking together the power of radio telescopes located in different parts of the globe, astronomers have been able to view extremely distant space objects with a clarity two million times greater than the acuity of human vision. If a person had such vision, he would see a grapefruit or a CD lying on the Moon.

The launch of this “virtual” telescope, called the Event Horizon Telescope, was driven by the development of Very Long Baseline Interferometry (VLBI) technologies over the past twenty years. The world’s largest millimeter radio telescope, the Atacama Large Millimeter/submillimeter Array (ALMA) observatory on the Chajnantor high plateau in Chile, operates on the same model and is also involved in the project. In the EHT project from April 5 to 14, VLBI technology turns all telescopes connected to it into a huge telescope the size of our planet. The powers of the world's most sensitive radio observatories in Chile, Spain, California, Arizona, Hawaii and south pole Earth. The largest of them, the aforementioned ALMA, consists of 54 parabolic antennas with a 12-meter diameter and 12 dishes with a diameter of 7 meters.

Another intriguing idea that can be explored in this experiment is the so-called "information paradox." This phenomenon is Stephen Hawking's prediction that matter trapped in a black hole cannot be lost beyond the known universe, but must somehow flow back out. This is what astronomers want to see how it flows. The energy or information leaving a black hole through Hawking radiation is a quantum effect. Scientists regularly see large plasma jets emanating from the center of galaxies where black holes are suspected or exist. If there is a connection between black holes and these jets (or other leaks of information and energy), then true event horizons in the strict sense are not formed for collapsed objects in our Universe.

Is Einstein right?

You cannot see the black hole itself, but you can see the matter falling into it. Dust, gas and nearby stars create a high-energy region around black holes, or the so-called accretion disk, in which matter is compressed and twisted, like in a funnel, and heated up. Thanks to high energies, matter begins to glow brightly close to the “event horizon” - the point after which the black hole does not release any radiation or information from itself. Thus, we see an image of matter “eaten” by a black hole, a kind of shadow of a black hole.

The modern standard cosmological model ΛCDM ("Lambda-CDM") assumes that general relativity is the correct theory of gravity on cosmological scales and our location in the Universe does not stand out in any way, that is, on a large enough scale the Universe looks the same in all directions (isotropy) and from each location (homogeneity). This too can be confirmed or denied.

Black holes combine properties described by the two main physical theories of our time - the theory of general relativity (the theory of large structures) and quantum mechanics (the theory of small distances). The enormous mass of a black hole requires the use of general relativity to describe the curvature of space-time caused by it. But the small size of a black hole and its internal processes require the use of quantum mechanics. So far it has not been possible to combine both of these theories. Combining theories leads to unnatural equations - for example, they imply an infinite density of a black hole. Earlier in 2015, the Event Horizon Telescope (EHT) had already measured the magnetic fields in the vicinity of this black hole, but their structure was extremely unusual - the strength magnetic field in certain regions of the disk it changed every 15 minutes, and its configuration was very different in different corners.

According to some calculations of Albert Einstein’s general theory of relativity, in the photographs we will be able to see a “crescent” of light surrounding an absolutely black “drop”. This light is emitted by matter just before it passes through the black hole's event horizon. Scientists expect to see many flares on the Sagittarius A* event horizon. These point flashes are periodically generated there from high frequency- once a day. Based on past observations, several observatories have observed what appear to be flares - brightening emissions from Sagittarius A*. As a result of current research, astronomers will be able to trace their origin and monitor the process of their decline.

If events develop successfully, hot spots will become a marker of the structure of temporary space in this strong gravitational region. "This opens the door to the possibility of tomography of time space - these spots move, they appear in different areas of observation," Avery Broderick, assistant professor of physics and astronomy at the University of Waterloo, said earlier at the EHT presentation. “There are only two places in the universe where you can study strong gravity on large, very large scales and around compact objects,” he reminds.
If we see something radically different from what we expect, physicists will have to reconsider, for example, the theory of gravity.

The first images of a black hole that you and I will be able to see will not appear until 2018. In the meantime, let's look at what we can approximately see in these images, constructed as a result of computer modeling.

Combining data and creating a big picture using Event Horizon Telescope measurements is a flawed task because each of the results contains an infinite number of possible images that explain the data. The challenge for astronomers is to find an explanation that takes into account these preliminary assumptions while still satisfying the observed data. The angular resolution of the telescope required to obtain sufficient data requires overcoming many challenges and makes unambiguous image reconstruction difficult. For example, at the observed wavelengths, rapidly changing irregularities in the atmosphere introduce measurement errors. Reliable algorithms that are capable of reconstructing images at fine angular resolution are constantly being sought.

So far, the task of cleaning, interpreting and combining the obtained data into one high-resolution image is performed by the CHIRP (Continuous High-resolution Image Reconstruction using Patch priors) algorithm, developed by a group of scientists from the Massachusetts Institute of Technology. However, if you are well versed in physics and mathematics, then the authors of CHIRP have published simple online tools for such scholars on the MIT website, with the help of which anyone with programming skills can create and test their own version of the algorithm for processing data from the Event Horizon telescope. Suddenly you will be able to see a problem from a completely unconventional angle and offer a unique method of solving it. I really couldn't find any information about the reward. But maybe I was looking poorly.

Included in the tool kit:

• Pooled training data set
• Real data measurement set
• A standardized dataset for testing image restoration algorithms
• Interactive quantitative assessment of algorithm efficiency on simulated test data
• Qualitative comparison of algorithm performance when reconstructing real data
• Online stand form for simulating realistic data, using your own image and telescope parameters

Geektimes has already written about the preparation of the EHT telescope

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Science

Astronomers first published hypothetical images of a black hole and reported that, according to their ideas, this mysterious space object should look like this. However, it should be recognized that none of them will ever be able to test their theory in practice.

Black holes in the visual sense do not fully justify their name - these objects are actually invisible, since even light entering them cannot escape their gravitational field.

However, scientists believe that the boundaries of a black hole, that is, the point of no return, which is called event horizon , must be visible due to the radiation emitted by the material that is absorbed.

At the 221st meeting American Astronomical Society scientists from University of California Berkeley presented a computer-generated image, reporting that this is what a black hole should look like:

Black hole of the Milky Way (photo)

Image of the Milky Way's black hole presented by Ayman Bin Kamruddin of the University of California

As you can see in the picture, a real black hole with boundaries has crescent shape, and not at all a shapeless object or just a black ball, as many portrayed it earlier.

The environment surrounding a black hole is quite interesting physics and emits a glow, the astronomers said. Technically, we can't see the black hole itself, but we can imagine what the event horizon looks like.

This image is not just the guesswork of astronomers and their rich imagination. The picture was created based on a model that scientists use to interpret images created using new equipment, which is currently under development.

Artists' ideas about a black hole are usually very primitive

New project called Event Horizon Telescope will collect data on the World Wide Web received radio telescopes from different parts of the world so that you can then depict objects that are too tiny to be seen, or at all not visible to the human eye.

The new telescope has already made a number of preliminary measurements and collected the first data on the black hole at the center of our Milky Way galaxy, known as Sagittarius A .

The researchers verified their findings using different models and came to the conclusion that the black hole, or rather, what surrounds it, has the shape of a crescent, and not something else. This form reflects "donut-shaped" disc of material, which revolves around a black hole and in one place is sucked into it.

The gas rotates around the black hole, and the side that faces observers on Earth will appear brighter due to special space processes. The other side of this will be darker. At the center of the crescent is a dark circle, which represents the black hole itself.

The center of the Milky Way with the black hole Sagittarius A. Image taken using NASA's Chandra Space Telescope

The first images of the black hole Sagittarius A, according to astronomers, will help them determine the mass of this object, which is at the center of our galaxy, and also test some aspects of general relativity that remain in doubt.

Other unique images of space objects and black holes

Many space objects with the help of modern technology can be photographed. These photographs and images are of great value to astronomers, who use them to make many discoveries. We invite you to get acquainted with the most interesting pictures, made using telescopes over the past couple of decades.

Astronomers have published images of very distant corners of space taken using a space telescope NASA Spitzer. The pictures show very distant objects, including supermassive black holes, or rather not the holes themselves, but the material surrounding them.

X-rays coming from heated material falling into a black hole

Traces of a black hole in the Universe

The bright “zigzag” on the right is not the work of an avant-garde artist at all, but signature of a supermassive black hole in the center galaxy M84, obtained using the spectrograph of the space telescope. This signature represents movement of gas trapped by the gravitational forces of a black hole. On the left is an image of the center of the galaxy, where the black hole supposedly “lives.”

The core of the M84 galaxy, photographed by NASA's Hubble Space Telescope

Black hole in space

The gravitational forces of the proposed black hole form Frisbee-like disc, which consists of cold gas and is located at the center of the galaxy. Later, Hubble observations confirmed the existence of huge black holes that absorb everything around them, even light.

A ring around the suspected black hole of the galaxy NGC 4261

Star cluster with black hole

This image shows the G1 star cluster, a large ball of light that consists of at least 300 thousand old stars. This object is also often called Andromeda cluster, since it is in Andromeda galaxy, the closest spiral galaxy to the Milky Way.

A globular star cluster in a nearby galaxy. The picture was taken using the Hubble Space Telescope in 1996

Big black hole

A giant black hole can release huge bubbles of hot gas into outer space. By at least, such a strange property was noticed in the black hole at the center galaxy NGC 4438. This galaxy belongs to the group peculiar galaxies, that is, galaxies that have an irregular shape. It is located in the area Virgo constellation and is located in 50 million years from us. The bubbles are actually a disk of material being swallowed by the black hole.

A black hole that "puffs up" incredibly hot bubbles of gas that are a consequence of the black hole's large appetites. The bubble has a diameter of about 800 light years

Elliptical galaxy with a massive black hole

This photo shows the central part elliptical galaxy M87 with the accompanying stream. The increase in brightness of the galaxy towards the center, which can be seen in the image, suggests that stars are concentrated in the core region and are held there by the gravitational field of a massive black hole. The plasma jet, which is also visible in the image and the source of which is a hot gas disk around a black hole, has a length of about 5 thousand light years.

NASA telescope photo taken June 1, 1991, showing the center of the M87 galaxy with the jet

Star cluster with dying star

Located at a distance about 40 thousand light years from the Earth in the area constellation Pegasus cluster M15 is one of 150 known ball star clusters, which form giant glowing rings and surround our Milky Way galaxy. All these clusters contain hundreds of thousands of ancient stars. If we lived somewhere in the center of this cluster, our the sky would shine with thousands of stars, which would burn both day and night.

Star cluster M15 with dying star in the center. Hubble telescope image showing the cluster in true color

There is no cosmic phenomenon more mesmerizing in its beauty than black holes. As you know, the object got its name due to the fact that it is able to absorb light, but cannot reflect it. Due to their enormous gravity, black holes suck in everything that is near them - planets, stars, space debris. However, this is not all that you should know about black holes, since there are many amazing facts about them.

Black holes have no point of no return

For a long time it was believed that everything that falls into the region of a black hole remains in it, but the result of recent research is that after a while the black hole “spits out” all its contents into space, but in a different form, different from the original one. The event horizon, which was considered the point of no return for space objects, turned out to be only their temporary refuge, but this process occurs very slowly.

The Earth is threatened by a black hole

solar system just part of an infinite galaxy containing a huge number of black holes. It turns out that the Earth is threatened by two of them, but fortunately, they are located at a great distance - about 1600 light years. They were discovered in a galaxy that was formed as a result of the merger of two galaxies.


Scientists saw black holes only because they were near the solar system using an X-ray telescope, which is capable of capturing X-rays emitted by these space objects. Black holes, since they are located next to each other and practically merge into one, were called by one name - Chandra in honor of the Moon God from Hindu mythology. Scientists are confident that Chandra will soon become one due to the enormous force of gravity.

Black holes may disappear over time

Sooner or later, all the contents come out of the black hole and only radiation remains. As black holes lose mass, they become smaller over time and then disappear completely. The death of a space object is very slow and therefore it is unlikely that any scientist will be able to see how the black hole decreases and then disappears. Stephen Hawking argued that the hole in space is a highly compressed planet and over time it evaporates, starting at the edges of the distortion.

Black holes may not necessarily look black

Scientists claim that since a space object absorbs light particles without reflecting them, a black hole has no color; only its surface—the event horizon—gives it away. With its gravitational field, it obscures all space behind itself, including planets and stars. But at the same time, due to the absorption of planets and stars on the surface of a black hole in a spiral due to the enormous speed of movement of objects and friction between them, a glow appears, which can be brighter than the stars. This is a collection of gases, star dust and other matter that is sucked in by a black hole. Also, sometimes a black hole can emit electromagnetic waves and therefore can be visible.

Black holes are not created out of nowhere; they are based on an extinct star.

Stars glow in space thanks to their supply of thermonuclear fuel. When it ends, the star begins to cool, gradually turning from a white dwarf to a black dwarf. The pressure inside the cooled star begins to decrease. Under the influence of gravity, the cosmic body begins to shrink. The consequence of this process is that the star seems to explode, all its particles scatter in space, but at the same time the gravitational forces continue to act, attracting neighboring space objects, which are then absorbed by it, increasing the power of the black hole and its size.

Supermassive black hole

A black hole, tens of thousands of times larger than the size of the Sun, is located in the very center of the Milky Way. Scientists called it Sagittarius and it is located at a distance from the Earth 26,000 light years. This region of the galaxy is extremely active and is rapidly absorbing everything that is near it. She also often “spits out” extinct stars.


What is surprising is the fact that the average density of a black hole, even considering its enormous size, can even be equal to the density of air. As the radius of the black hole increases, that is, the number of objects captured by it, the density of the black hole becomes less and this is explained simple laws physics. So the largest bodies in space may actually be as light as air.

Black hole can create new universes

No matter how strange it may sound, especially against the backdrop of the fact that in fact black holes absorb and, accordingly, destroy everything around them, scientists are seriously thinking that these space objects could give rise to the emergence of new universe. So, as we know, black holes not only absorb matter, but can also release it at certain periods. Any particle that comes out of a black hole can explode and this will become a new Big Bang, and according to his theory, our Universe appeared that way, therefore it is possible that the Solar system that exists today and in which the Earth revolves, populated by a huge number of people, was once born from a massive black hole.

Time passes very slowly near a black hole

When an object comes close to a black hole, no matter how much mass it has, its motion begins to slow down and this happens because in the black hole itself, time slows down and everything happens very slowly. This is due to the enormous gravitational force that the black hole has. Moreover, what happens in the black hole itself happens quite quickly, so if an observer were looking at the black hole from the outside, it would seem to him that all the processes occurring in it were proceeding slowly, but if he fell into its funnel, the gravitational forces would instantly tore it apart.