10 interesting facts that you should know about black holes
Imagine matter, packed so tightly that nothing could leave its limits. No moon, no planet, not even light. Those black holes - the point at which the gravitational force is so great that it is a danger to all that accidentally enters a fateful line near the black hole. We often talk about where are the black holes are and why they are so important. Below you will find ten facts about black holes - brush up on your knowledge of these beautiful objects.
1. You can not see a black hole directly.
Because a black hole is truly black - light can not escape its limits - it can not be seen directly, using our tools, regardless of what type of electromagnetic radiation, you see (visible light, X-rays, or whatever). But we can see the effects that the black hole has on the immediate environment. For example, the star was too close to the black hole. The black hole naturally attracts the star and breaks it apart. When the matter of the star begins to be absorbed by the black hole, it is accelerated, it becomes hot and glows brightly in X-ray spectrum.
2. In the Milky Way, most likely, there is a black hole.
Clearly, many are concerned the question of how a black hole is dangerous and threatens the world though there is any possibility to be absorbed by the object? The answer is no, astronomers say, although there is a certain probability that the enormous supermassive black hole hidden at the center of our galaxy. Fortunately, we are quite far from the monster - roughly two-thirds of our galaxy from the center - but its effects can be observed from a distance. The European Space Agency says that the black hole in the center of the Milky Way is a million times more massive than our Sun, and is surrounded by amazingly hot gas.
3. Dying stars create a stellar black holes.
Let's say you have a star 20 times as massive of our sun. Our Sun slowly fade; When nuclear fuel is over, the sun slowly become a white dwarf. But with more massive stars does not. When they run out of fuel, gravity suppresses the natural pressure of the star and pushes it inside. When the pressure of nuclear reactions collapses, the gravitation severely squeezes into the core of the star, its outer layers fly in space. This is called a supernova. The remaining core collapses into a singularity - a point of infinite density and zero volume almost. Singularity - the heart of a black hole.
4. Black holes come in different sizes.
There are at least three different types of black holes, NASA claims, ranging from relatively small to those located in galaxies. Primordial black holes - the smallest, their sizes are from a single atom to the whole mountain. Stellar black holes, the most common type, up to 20 times more massive than our sun. And there are monsters in the centers of galaxies - supermassive black holes. They reach millions of solar masses and more. How do these monsters are formed, it is still not really clear.
5. around black holes, strange things happen.
This is best illustrated by the following example. One man (we'll call him a loser) falls into a black hole, while the other person (Lucky) - looks. From the perspective of the lucky watch Jonah will tick slower and slower. This is because according to Einstein's general theory of relativity, time depends on how fast you are moving when you pick up to extreme near-light speed. The black hole distorts space and time so that the time of Jonah is slower. However, in his view the clock runs normally, but at the Lucky - in a hurry.
6. The first black hole found only with the advent of X-ray astronomy.
Cygnus X-1 was first discovered during a flight in a balloon in 1960, but ten years this place has been identified as a black hole. According to NASA, this black hole is 10 times more massive than the sun. Next to it is a blue supergiant star about 20 times more massive than the sun. A black hole sucks in the star, and she glows brightly in X-ray spectrum.
7. Considers that the nearest black hole - 1,600 light-years.
Erroneous measurement V4641 Sagitarii led to the news that the nearest black hole to us is too close to Earth, only 1,600 light-years. Not close enough to be dangerous, but it is much closer than you think. Further investigation showed that the black hole is much further. Looking at the rotation of its companion star, as well as other factors, the scientists in 2014 provided more accurate results - 20 000 light-years.
8. We do not know whether there are wormholes.
A popular topic for a science fiction story - this is when someone falls into a black hole. Some people believe that these objects are a kind of wormhole wormhole standards in other parts of the universe, allowing to travel faster than the speed of light. But the truth is that we still do not know how to describe them in terms of physics. "We have no theory that would unite general relativity with quantum mechanics, we do not know the whole zoo of possible structures of space-time, which could accommodate wormholes" - says Avi Loeb, a physicist at the Harvard-Smithsonian Center for Astrophysics.
9. The black holes are dangerous, but if you find yourself too close.
As people at the zoo, we can observe black holes only if you are outside the event horizon - you can imagine it as a planet's gravitational field. This area is a point of no return, if you get too close, you have no chance to escape. But outside of this area of the black hole can be safely observed. In a broader sense, it means that the black hole is unlikely to absorb the entire universe (unless, of course, in our understanding of the physics of the cosmos does not happen a serious revolution).
10. Black Holes - pets of science fiction.
Taken as many films with the participation of black holes, it is impossible to list them all. Of the latter, it may be noted "Interstellar" by Christopher Nolan - it people travel through the universe to look at the black hole. "Event Horizon" explores the phenomenon of artificial black holes - something like that discussed in the "Star Trek." Obviously, these mysterious objects that distort our perception of reality and simply do not fit into the average person's head, popular with writers, writers and directors - also, in general, not ordinary people.
