Black holes are part of the time-space that has the strongest gravity, so light alone cannot escape from it. According to General Relativity theory, it takes a large mass to create a Black Hole in the Time-Space. Around the Black Hole, there is a surface that is called Horizon events. This object is called "black" because it absorbs whatever is around and can not come back, not even light. Theoretically, black holes can possess any size, from microscopic to the observable size of the universe. The Quantum Field Theory in Curved Space-time predicts that Event Horizon emits nearby radiation with limited temperatures. This temperature is inversely proportional to black hole mass, making it difficult to observe black holes with a mass of stars or more.
The black hole was first proposed by John Michell in the 18th century and Pierre-Simon Laplace, developed by German astronomer Karl Schwarzschild, in 1916, based on Albert Einstein's general theory of relativity, and increasingly popularized by Stephen William Hawking.
The term black hole became popular when John Archibald Wheeler used it in his lectures in 1967. Although he was widely regarded as the first originator of this term, he always refused to say that he was the inventor of this term.
Black holes are formed when a massive star dies and compresses into a very small ball. Gravity is very strong and even able to swallow the light passing too close. Formed from the death of a massive mass star who ended his life.
A black hole is an object whose escape velocity reaches or even exceeds the speed of light. The gravitational field of such an object is so extreme that in order to escape its gravitational pull we need the speed of light or even greater than the speed of light to get out of it. Since no object can move beyond the speed of light, then practically no particle of any kind can escape the black hole when it has entered a certain distance from the black hole.
Until now has been found three types of black holes. The first black hole is named stellar and is the smallest compared to the other two. Stellar black holes are formed when a star larger than our sun dies. Although the size is relatively small, the object is so dense. Imagine an object that measures one big city on earth but has a mass three times bigger than the sun, that's a stellar black hole. Scientists believe that there are hundreds of millions of black holes like this in our galaxy.
Second, is a miniature black hole. Scientists predict that this type of black hole formed shortly after the Big Bang, which is believed to be the beginning of the universe's 13.7 billion years ago. Until now no one has been able to find this type of black hole.
The third is a supermassive black hole and is believed to be the largest black hole today. There is no research that mentions exactly how this black hole can form. The size may be as big as the sun but with a mass of billions of times that of the sun itself. Its location is right in the heart of all galaxies, including our galaxy Milky Way or the Milky Way.
Black holes absorb everything around them, including light, then its existence is difficult to detect. However, recent studies suggest that there is one black hole closest to the earth. V616 Mon (A0620-00) coded in the constellation of Monoceros and 3,000 light years away. Has a mass of about 13 times the sun.
Just as you are observing a beast from outside the cage, it does not matter if you observe a black hole from the outside "cage." In this case, the cage is called horizon event. If you enter this area, you can not go back.
You are allowed to observe black holes outside the area. Even if you are a scientist or someone with an interest in researching this hole. Hence, though horrible, it is impossible for a black hole to suck out all the objects in the universe.
But what happens if humans are sucked in black holes? This question is one of the most interesting and often catapulted. Then how the explanation? Say, you're inhaled by a black hole the size of the earth. If that happens, your body will look like a toothpaste sticking out of its container, stretching and stretching. A British astronomer Sir Martin Rees called this phenomenon the name "Spaghettification."
If you are still alive when sucked into it, you will experience the bending of space-time and you can witness everything that is inhaled into the hole before and after your exposure. This means that you will be able to see the entire origin of the universe, from the Big Bang to the end of the history of the universe itself.
Although no relation with astronomy, the term supermassive black hole began to familiar in the ear when one of the British band sang songs with the same title. As explained above, that scientists believe that every galaxy has a supermassive black hole, including our galaxy.
Supermassive black hole named Sagittarius A has a mass of four times greater than the sun. Although this black hole, which is nearly 30,000 light years away, is now inactive. But they believe that two million years ago, this black hole once exploded, and its explosion can be seen from the planet earth.
To understand this, imagine two twins. One of them settled on earth, while the other one flew into space with the speed of light until at a point stopped, and then turned back toward earth. The twins who travel to space will be much younger than the twins who remain on earth. Because, the sooner you move, the slower the time from your perspective.
When you arrive at the event horizon, you move at a very high speed due to the strong gravitational force of the black hole, at which time from your perspective will slow down. If you are still confused, try watching the output of 2014 film, Interstellar, claimed Christopher Nolan.
Although the black hole has a tremendous power, apparently over time, this object can be extinct. This surprising discovery was first predicted by physicist Stephen Hawking in 1974. As the name implies, this phenomenon is called Hawking radiation.
Hawking radiation breaks the mass of the black hole into space around it all the time until no energy is left from the black hole itself. Hawking radiation is also known by the evaporation of a black hole.
Those are some extraordinary things and facts from black holes. I wonder how long the mystery of this black hole can be revealed. Perhaps all the secrets of this object and the universe as a whole little by little will be revealed along with the increasing sophistication of technology developed by mankind.
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