Thinking experiments are a great thing. We can imagine what will happen if the Moon disappears, and we suspect that our ancestors saw the supermassive black hole of the Milky Way. We guess that the moon was not always dead and cold, and that rivers and seas once flowed on Mars. But we are on the edge of the galaxy, and black holes for us almost do not exist. What if one of them formed in the solar system? Is this possible in principle?
Strange things began to happen in the night sky. You, like many others, actively follow the news. The president speaks, he is supported by astrophysicists, geologists and climatologists. He is nervous, but paying tribute to tradition, he divides the news into “bad” and “good”. Good news: we have not died, the planet has not been destroyed, it has not been carried into space and has not been unwound in a gravitational wheel. Bad: we are waiting for "very interesting climate change." Trying to survive near a black hole is like fleeing the Titanic - for the sake of cold death in the ocean.
Before you reach for the alarmcase or start to go crazy: do not be afraid, this is just a mental experiment. Black holes are one of the worst phenomena in the universe. Their tremendous weight bends space and time - and our understanding of their nature - to the limit, to one point. Supermassive black holes (like this one) hide in the nuclei of galaxies, absorbing millions, billions of stars. The most accurate image of a black hole to date, we observed in the film "Interstellar". In fact, this phenomenon is many times worse.
What happens if a black hole is born or is discovered near our solar system?
- 1 Greetings from the Abyss
- 2 Curving space and time
- 3 time has come
- 4 Good and Bad News
- 5 Beyond the Event Horizon
Hello from the abyss
The most accurate black hole image so far
You will have to figure it out in order. How close is it? Where from? What is the mass?
It should be noted right away that our sun neverwill become a black hole. To do this, we need a mass that exceeds the solar mass by a factor of 10-15. Then a gravitational collapse will occur, and under the influence of gravity the matter will literally collapse at one point. A similar phenomenon lies at the heart of hydrogen bombs and in the theory of cold fusion, unless gravity plays a different role. Moreover, other stars in neighboring galaxies are not suitable for the role of potential black holes. Most of them are red dwarfs and have a mass of 8-60% of our sun.
Two options remain: either a black hole spontaneously appears in our environs, or it comes from nowhere. The first would be possible if all the fears around the Large Hadron Collider acquired meaning and created a black hole artificially. But no, that’s not possible.
Regarding the second, astronomers and astrophysicistsconfirmed the existence of about 2,000 wandering black holes, but the chances that one of them will reach us are close to zero. And as writer Douglas Adams noted:
“The cosmos is great. You simply cannot realize how incredible and breathtakingly great it is. I mean, it may seem like a long road to the pharmacy, but by the standards of space it’s seeds. ”
However, the probability of a black hole is too interesting an event to pass by.
Warping space and time
If you look at the black hole from afar, itwill be like any other massive object. While it is right in front of you, it obeys the laws of classical mechanics and the Newtonian law of universal gravity, which states that the attraction between two objects is proportional to their mass and decreases with increasing distance. In other words, there is no gravitational difference between R136a1, a “blue” dwarf weighing 265 suns and a black hole with the same weight.
Go closer to the black hole to get intoits gravitational field, and you will come across two different sets of rules. With Einstein's general theory of relativity, which allows the existence of black holes that distort space and time, and extreme gravity, which takes this curvature to extremes.
If you want to explore a black hole without crawling outspaceship, you will find that the closer you are to the center of the huge mass, the more your engines will tear to keep you in a circular orbit. First, small rocket pulses can stabilize it; but the farther, the more energy you have to spend, so as not to leave orbit. As a result, only the non-stop operation of rocket engines will separate you from all-consuming nothing. However, in the film Interstellar - and this is due to Christopher Nolan and Kip Thorne - these effects were shown to be surprisingly decent.
As soon as you run out of fuel (or yousuddenly decide to turn off the engines), you will cross the event horizon of a black hole, the boundary due to which even light cannot return. After that, you will have to answer for all your sins. Nothing will stop the inexorable movement towards the singularity - the core of infinitely compressed space and time, where physics, as we know it, turns into a ball and whines.
As you progress, time will beslow down. Very much. From your point of view, nothing will change, but your friends watching your trick will see something like blurry lightning. But only to the horizon of events - the light does not go beyond it, which means that no one can see you. The perfect crime, right?
Gravitational curvature of time - a phenomenonordinary enough, but too weak to be noticed. On Earth, for example, having lived a billion years at sea level, you will be a second younger than your peer who lived on top of Everest. They say that time is afraid of the pyramids, but you have to spend too much time leaning against her cheek to feel the slowdown in time in Paris.
In a black hole, time spins around. When we say that falling into a singularity cannot be avoided, it means not only the inexorable action of gravity or distortion of space. Time in a black hole is compressed to such an extent that the path to the singularity literally becomes your future. Escaping from a singularity will be like trying to stop time.
What happens to our solar system if it suddenly experiences the wrath of a black hole and falls into its whirlpool?
The time has come
Let's say we have a black hole that is lockedin a double system in an embrace with a star that is preparing to become a supernova. Suddenly this happens, the gravitational giant shoots in our direction at a speed of tens and hundreds of kilometers per second. How do we know about this?
The answer is simple: we won’t know until he collides with something, because the massive gravity of black holes does not even release light. So, instead of trying to find black pepper on a black carpet, let's look at a few ways that will help us directly identify a black hole.
First, matter torn by a black hole will emit radiation as the accretion disk rotates. The space around will glow like a Christmas tree in the darkness of night.
Secondly, the distortion of the space around blackholes can be detected by earthly methods. For example, using gravitational lensing, predicted in the framework of Einstein's general theory of relativity. The effect manifests itself near massive objects and is recorded by astronomers. The same method is used to search for dark matter.
But even under ideal conditions, detect blacka hole in this way will be more difficult than finding a flea on a spotted dog at night with binoculars. With a blindfold on the eye. For a successful gravitational lensing, a black hole must pass between us and the star. And after that we still have to get lucky.
In addition, a black hole can make itself felt,if it interacts gravitationally with celestial objects like planets, stars, asteroids and comets, which again brings us to the key question: how close will our hypothetical black hole located in the neighborhood be located?
Of course, the closer, the more dangerous. As they approach the orbits of the planets and moons, they will dance like a sparrow caught in a web, dragging orbital curves behind it and disrupting the order that they have been trying to assemble in parts since the time of Nikolai Copernicus.
Here on Earth, the tides and ebbs ofthe color of the sky. If gravity, as ordered by Zhirinovsky, alienates the planet’s orbit farther from the Sun, makes it closer, makes it more elliptical, at best we will suffer from changes in temperature and strangeness with the seasons. In the worst case (in addition to becoming part of a black hole), the Earth may fall on the Sun or go on a long voyage into the depths of space, dooming us all to cold death.
The famous astrophysicist Neil de Grass Tyson once succinctly expressed the problems that would arise if a “black guest” was found nearby:
“If a black hole visits us, the solar system will have a bad day.”
Well, since we are doomed, let's gather our courage and dive towards the singularity.
Good and bad news
In Russian, there is a six-letter word thatwould best describe what awaits us. Let's call it just hopeless. Scientists learned to divide by zero, and we ended up in a black hole. Even Bruce Willis, with a brave crew of oil workers who had undergone special training in Chelyabinsk, would not have saved us.
If a black hole appeared in the vicinity of Neptune, we wouldimmediately felt it. Scientists know the orbit of Neptune so well that they can even detect a deviation of 1 arc second (unit of angular measure). An ordinary black hole with a mass of ten suns flying at a speed of 300 km / s would betray itself at a distance of one tenth of a light year.
And here is the last piece of good news: a black hole of this size will give us a minimum of 100 years to complete our earthly affairs. Perhaps a danger of this magnitude will stop all earthly wars or start one global one. Perhaps humanity will have time to destroy itself on its own, as soon as it finds out that in a hundred years - everything, kaput. It doesn't matter so far. If the hole moves more slowly, the fatal waiting time will increase tenfold. And then there should be enough time for building an ark or collecting a planetary suitcase with things.
As you approach Neptune, black deathpulls the gas giant from orbit. The planet begins to behave strangely: as it moves away from us, a red shift occurs - the wavelength of its radiation, including light, goes into the red spectrum. As soon as Neptune is behind a black hole, the gravitational lens stretches over the black sphere and flows around it. When the planet appears again, already in front of us, its colors undergo a blue shift - the wavelength goes to this end of the spectrum.
The red and blue shift, as a rule, is a consequence of the removal or approximation of a stellar object in relation to us. Similar to the Doppler effect.
However, as a black hole "eats" the planet,the gas will spin in a gravitational spiral, like sugar during the creation of cotton candy. From our point of view, the spiral will forever go to the event horizon. But the light emitted by the death of Neptune will be reflected from the black hole in the negative, like the solar corona during an eclipse.
The closer the black hole is to the Earth, the more the surrounding distortion effect will appear, as in a crooked mirror. All telescopes will see only the void in the center of the black hole.
If our black death is supermassiveblack hole, history will end - its event horizon will be five times larger than the solar system. But it's boring. Let's take a smaller example and still try to make out the insides of this monster.
Beyond the Event Horizon
We move along the rabbit hole, knowing that yourgetting to know her will be very short. We hope that we will at least have time to evaluate the interior of the black hole. Fortunately for us, but unfortunately for the Solar System, this black hole is supermassive. We changed the rules, but if we hadn’t done this, everything would have ended for some reason.
In a small black hole - say, with a mass of 30suns - tidal forces caused by an increase in gravity would tear us apart long before we reached the event horizon. But there gravity is about a million earthly. In order to enjoy the victory - because we have reached the event horizon - we will not have 0.0001 seconds.
In a supermassive black hole with a mass of 5million suns, like the one located in the center of our galaxy, a completely different experience awaits us. Any black hole that has absorbed a mass of more than 30 thousand suns has tidal forces with gravity less than one earth on the event horizon. We will have 16 seconds to look around (and change the rules of the game) before we reach the point of singularity. The more mass, the more time.
Falling through an event horizon is like a processfalling asleep or falling in love: it is difficult to determine the starting point when this happens, but after that your sense of reality will be completely different. You will see stars in a black hole (light enters, but not vice versa), but the space around it will resemble a soap bubble.
Well, after you are crushed to zero, youyou will reach a point of infinite curvature, where the time and space known to us comes to an end. And to learn how physics works at this point of infinite curvature of time and space, infinite mass and density, we simply do not have the opportunity. Sometimes it seems that the heart of a black hole will reveal to us all the secrets of the universe or raise an infinite number of questions. But this is just a guess.