Nearest black hole(or neutron star)

According to NASA, astronomers, using Chandra X-ray observatory had almost found a youngest possible Black hole known to exist in our cosmic background, and they even said that it appears to be our nearest possible. The 30-year-old object provides a unique opportunity for them to watch a black hole develop from infancy.

The black hole appears to be the remnant of SN 1979C, a supernova in the galaxy M100 approximately 50 million light years away from the earth. NASA's Swift satellite, the European Space Agency's XMM-Newton and the German ROSAT observatory revealed a steady flow of bright X rays from a source during their observation from 1995 to 2007. and suggests that this could be the black hole being fed through the material that is falling in to it from the supernova or possibly from a binary companion.

"If our interpretation is correct, this is the nearest example where the birth of a black hole has been observed," said Daniel Patnaude of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. who led the study.

Scientists think that the SN 1979C--first discovered by an amateur astronomer in 1979--was formed when a star about 20 times more massive than the sun collapsed--gravitational collapse.

SN1979C, obviously is different from other black holes that had been found so far, as it doesn't produce any Gamma-Ray Bursts (GRBs). GRBs are something, scientists relied on so far to found the black holes, but SN 1979C belongs to a class of supernovas unlikely to produce Gamma-Ray Bursts.

"This may be the first time the common way of making a black hole has been observed," said co-author Abraham Loeb, also of the Harvard-Smithsonian Center for Astrophysics. "However, it is very difficult to detect this type of black hole birth because decades of X-ray observations are needed to make the case."

The idea of a black hole with an observed age of only about 30 years is consistent with recent theoretical work. In 2005, a theory was presented that the bright optical light of this supernova was powered by a jet from a black hole that was unable to penetrate the hydrogen envelope of the star to form a GRB. X-ray data from Chandra and the other observatories fit this theory very well.

However they are not yet ready to confirm this--as a black hole--as there exists some intriguing possibility: A young, rapidly spinning neutron star with a powerful wind of high energy particles could be responsible for the X-ray emission.

Whatever the case could be, they can be still happy as this is our youngest neutron star so far and a brightest example of a "pulsar wind nebula". The Crab pulsar, the best-known example of a bright pulsar wind nebula, is about 950 years old.
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Theory of relativity as basis for Black hole.

Einstein's Theory of relativity is definitely one of those few theories in the history of physics, that changed the way we see things. It revolutionized the cosmology in such a way that many physicists who are struggling in their respective lines of research produced some shockingly interesting results.

Black holes is one such shocking yet interesting result....

So, what is a black hole?

Well, there are a lot of definitions, and in the simple possible way: A Black hole is a region in space-time with such an immense gravitational pull towards its center that even light cannot escape out of it.

How is Einstein's 'Theory of relativity' responsible for its formation?

Black hole is a subject where its formation is almost entirely based on theoretical evidences rather than physical evidences(strong). All these theoretical proofs are in fact been implied from the Theory of relativity.
To get some idea about its formation and stuff, we must know the life cycle of a star as a prerequisite.

A star takes birth when large amount of nearby gaseous particles(mostly hydrogen) attract towards each other and get squeezed.
In this process of contraction, particles collide with each other to produce large quantities of heat energy. This heat in fact is responsible for the star to shine brightly. The heat thus produced would be so immense that, the particles when they come closer will no longer collide but coalesce, and forms higher elements like helium, Lithium, Berilium...along with some amount of heat. Heat that got released in this process, creates high pressure between the particles and tries to drive them away, opposing the contraction process. The more the star tends to contract, the more will be the opposing pressure.
At some stage there will be a perfect balance between the contraction(force) and expansion(force) helping the star to remain stable. The star thus remains stable for quiet a long period of time(million millions of years) till one of its forces gets weaker. Obviously, it can't be the gravitational force(contraction) that gets weaker.
The pressure inside the star eventually gets weaker, and the denser particles that gets cooled drift towards the center of the star, re surging the contraction process. This process continues till it reaches a stage where, the contraction force gets even by the repulsions between subatomic particles(electrons, protons, and neutrons). The star thus remains stable again for the second time.

The star that gets balanced by the repulsions between 'electrons' is termed as a
'White dwarf' with a radius of about few thousand miles and with a density of about hundreds of tons per cubic inch. And the one that is supported by the repulsions between protons and neutrons was popularly named as 'Neutron star' with a radius of about ten miles(only) and density, hundreds of millions of tons per cubic inch.

This would be the final stage of every known and unknown star that exist in our known and unknown universe, if the subatomic particles could move with out any limit. But, according to Einstein's Theory of relativity, nothing can travel faster than light.

Here comes the interesting question: What if the star is so heavy that it requires the electron(or proton or neutron) to move faster than light--to balance the immense contraction(force)?

These kinds of movements or repulsions among the subatomic particles are impossible according to the Theory of relativity and hence the star ends up in a gravitational collapse, and forms an infinitely dense region, popularly called as a 'Singularity'.
The star that gets vanished in to a 'singularity' still exerts the same, finite light trapping gravitational pull(can be more but not less) up to certain distance in space creating a 'Black hole' around it. The boundary of this 'Black hole', the 'Event horizon' is formed by the paths of light just managed to move around but can't escape.

Thus the whole Black hole formation was almost based on Einstein's 'Theory of relativity'.

What if the electrons under those special conditions(gravitational collapse) could move with out a speed limit--faster than light ?

There will be no 'Singularity', no 'Black hole' but will be a 'Black star' or 'Dark star' that still can trap light.
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