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1) What is a Black Hole ?

A black hole is a place in space where gravity too strong because matter has been compacted into a tiny space. This can happen when a star is dying.

A Black Hole is composed of 3 layers :
-The singularity, is the center of the black hole.
-The event horizon, the atmosphere of the black hole is a part where the light can’t escape. It’s like the earth’s atmosphere.
-The Ergosphere, the outer part of the event horizon.

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A Black hole can be bigger than a few million Earths and it is called "supermassive”, these kind of black holes are created out of a supernova, a star explosion.

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Another type of black holes could be small, as small as one atom. These kind of black holes formed when the universe began.

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2)What tools are used to observe Black Holes ?

Gemini Observatory

It is an optical telescope located in the Chilean Andes.

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The European Southern Observatory

It is the first telescope in the world to have a computer-controlled main mirror, it is located in Chile.

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National Radio Astronomy Observatory

This telescope uses radio waves to study celestial objects. It’s located in North America.

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The Chandra/Spitzer Space Telescope

It uses X-ray to have a better view of the highest-energy regions of space.

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3) Who discovered Black Holes?

The first person to predict black holes was Simon Pierre LaPlace, in 1796, he said: "...[It] is therefore possible that the largest luminous bodies in the universe may, through this cause, be invisible." And after him Albert Einstein published the Theory of General Relativity, which predicted spacetime curvature in 1915.

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At the end we were able to detect them because they emit x-rays and other forms of electromagnetic radiation.

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4) Myths or reality.

1- Black holes do not go around in space eating stars, moons and planets.

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2- The sun will never turn into a black hole it is not a big enough star to make a black hole.

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3- If our sun was to be replaced by a black hole Earth will not fall into it because no black hole is close enough to the solar system for Earth to do that.

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4- In science fiction shows, people sometimes travel through wormholes. Many students think black holes are wormholes and therefore lead to other places. Wormholes are an intriguing possibility, but have not been shown to exist.