Black Holes - The Mystery

Albert Einstein first predicted the existence of black holes, by his calculations of General Relativity. Black holes are never seen, they are just predicted. As even light can't escape from it, we can't see them actually. But, still scientists use advanced telescopes to see, where stars and planets move fast. It is observed that many stars are moving faster in centers of galaxies. These holes form, when stars die, and their surface gets directed to its own gravity field, making a hole. Its gravity is so powerful that the star gets crushed into its own gravitational field which is so small. This sucks everything near it, even light can't escape it.  As there is no object on universe, which is faster than light, that means that everything gets sucked through it. Black holes' size increase when they suck mass, and suck other stars and black holes. Below is a brief description, of how black holes form, and their history:

How Black holes form?

     

Stars like sun, carry out nuclear reactions in their core and on the surface. The mass of the core is so huge but the nuclear reactions taking place on the surface balances them. When the nuclear fuel is spent on the surface, only the helium atoms and the core remains. At this time, helium atoms fuse to form carbon. This creates enormous amount of energy in a very short time, which causes an explosion which is known as a supernova. 

So, the outer surface is gone, which leaves the core behind. Due to the reactions in the core which forms many elements having mass greater than hydrogen (but the total mass is the same), the core starts to shrink further and further. This shrinked core is called a neutron star as the protons and electrons combine to form neutrons at this time. If it shrinks so much to a single point, called singularity, then it is called a black hole. It bends the space time so much, which gives a impression of a hole. Its gravitational force becomes so large that light can't escape it. 

                                        

Many predict that black holes are in centers of all galaxies, but don't suck near by objects, because their mass is gravity is not so strong. Our sun's mass is very small to become a black hole, so it will become a white dwarf, which just reflects near by light, just like our moon.  

Event Horizon

Event Horizon is just an area near the black hole. If something goes through this area, it means it won't escape the black hole. Here, only entry is possible, no exit. The more mass of the black hole, larger the event horizon.

How to see a black hole

We can never see a black hole. But still we can observe by seeing where objects move faster. Where gravity is more, objects move faster. This can be proved, as Mercury closer to sun, travels faster in short distances, when Earth travels slow, even in long distances. So, scientists predict that black holes are in centers of many galaxies, as they observed that stars and objects are moving faster in centers.

Prediction of white holes

                                                                 

There was a prediction of 'white holes', as when things gets sucked into black holes, must sometime come out. They are predicted to come out through white holes, which are also never seen, and never studied about them, how they form. These white holes emit energy, which is sucked by black holes. Many scientists believe that the Big Bang was the energy coming out of the white hole, forming our galaxies and solar systems. These black and white holes are predicted to be connected by what called as ' worm holes '. 

                                                        

This wormhole is a path, that leads sucked objects by black holes, to come out through white holes. When this prediction was made, Einstein suggested that when we connect a black hole today, and a white hole in the past by a wormhole, a time machine is made. When we are sucked by black holes, we come out in past through white holes. So, everything goes into past, which are being sucked. But, there is no such explanation, by which we can go in future, by black and white holes.

Will Earth will be destroyed when The Sun becomes a black hole:

No, earth will not fall into that black hole, because Sun is not so large, to become a black hole. So, Earth will not be destroyed by Sun's Black hole.

                                                                                                                     Article by - M. Santosh
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