What is a Black Hole?

A black hole is a place in space where gravity pulls so much that even light can not get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star with ten times the mass of our sun dies.

Because no light can get out, black holes are very hard to detect. Albert Einstein first predicted black holes in 1916 but not until 1971 we actually detected one.

To detect a black hole, various methods are used, one is that we observe the stars following irregular orbits around the center of a galaxy.

The idea is that, highly massive objects such as stars to follow such an orbit, there must be something with an incredible amount of mass.

How does a black hole form?

All the stars are gigantic nuclear reactors with extreme gravity. For the star's entire life, nuclear fusion and gravity are locked down.

A star is mostly hydrogen at it's early years of life. It forms helium within the fusion process thus radiates light. It continues to form heavier elements until the core is iron and there is nothing to fuse. The star basically runs out of fuel.

After the center of the star turns into an Iron ball, the fusion stops and gravity wins. When the star's extreme gravity cause it's core to shrink to its maximum density. A black hole is born. And the black hole starts consuming the star from the inside.

And once it swallows enough matter, it beams two powerful beams that are called Gamma Ray Burst.

These jets of beams are so powerful that they destroy anything on their way.

This includes the surface of the gigantic star. So when this happens, it causes the star to explode. In one second, the star releases more than 100 times energy that our sun will ever produce on it's entire lifetime. This event is called a Hyper Nova.

What's left is a beautiful Nebula that's across thousands of light years and will eventually form many star systems like our home.

And an invisible monster sitting in the middle of it.