We all are aware of this new sensational news of black hole. Everyone is talking about the picture of the black hole and asking about others opinion on it, but do you really know what black hole is? or what made it occur?
What is a Black Hole?
Stars are an incredibly massive collection of hundreds of atoms consisting of a luminous spheroid of plasma held together by its own gravity. Nuclear fusion in the star crushes nitrogen atom to helium atom releasing a tremendous amount of energy. This energy in the form of radiation pushes against gravity maintaining a delicate balance between the two forces.
A star remains stable as long as there is fusion in the core. But for stars with more mass than the sun the heat and pressure at the core allow them to fuse heavier elements until they reach iron. The fusion process of iron doesn’t generate any energy. Iron builds up at the centre of the star until it reaches a critical amount between radiation and gravity is suddenly broken. The core collapses. Within a fraction of seconds, the star implodes.
Moving at about a quarter of the speed of light feeding even more mass into the core. It’s at this very movement that all the heavier elements are formed as the star dies in a supernova explosion. This leads to either a neutron star or if the star is massive enough the entire mass of the core collapses into a black hole.
What you see in the picture of a black hole is the event horizon. The Event horizon is the border at which the gravitational pull becomes so powerful that nothing can escape through it. The light emitted from inside the event horizon can never reach the outside observer, and the outside observer cannot see beyond the event horizon.
This is similar to a black body. A black body is a body which doesn’t reflect light that is incident on it. For example, consider a spherical device with just a opening in the form of hole. The inner surface of the spherical body is covered by lamp black. Now, if light enters the body through the hole, it gets reflected internally and all the light waves get absorbed. No light comes out of the black body.
Similarly, if someone crosses the event horizon of the black hole. He is pulled towards the core and eventually disappears and dies. How soon you die depends on the size of the black hole. A smaller black hole would kill you even before you enter the event horizon, while you probably could travel inside a super size massive black hole for quite a while.
For example, the super massive black hole S50014+81 is 40 million times the mass of the sun.