Question: The surface gravity is so great that no ray (particle) light inside the hole does not have enough energy. Planets can't be attracted to the force of black holes? Black holes could be absorbed by other black holes? Why and when are black holes appear?

Hi Adriana,

Black holes…fascinating right! maybe the most crazy objects we have in our universe. I can tell you what i know about them.

Black holes are formed when a very big and heavy star (think 1000 times our sun) dies. When a star dies it means it used all its energy to produce light and heat and on that moment everything that is left from that star collapses into a small ball, sometimes just as small as a village! You can imagine that this gives a big blast. Sometimes, if the star was very big and a huge amount of material collapses into something very small, even the inside of atoms can not stand all this force and pressure and violence anymore, so they also start collapsing into, well, nothing… It’s quite hard to imagine. When this happens everything in this small ball starts collapsing even further, into to the center of the ball, until nothing is left. This is a black hole.

A black hole was formed from a lot of material, that all collapsed and got sucked inside, so it is very heavy, which means its gravity is very strong. anything that comes close, be it dust, planets, stars, anything, will get sucked up by the black hole and disappears into it, because the gravity pulls it in. Actually the planets and stars are the easy victims, they are heavy, so easily affected by gravity, and don’t move so fast. The difficult guys are the rays of light. They weigh practically nothing and move with extreme speed so very difficult to catch. however, there is a point close to the black hole where the force of the black hole becomes so strong that even light can not escape anymore. therefore we say that if even light can not escape, nothing can, and this point we call the horizon of the black hole.

Black holes can be absorbed by other black holes to make a kind of super black hole. They are just like big monsters eating anything that comes on their path and with every bite the become bigger and heavier and can grab even more. Have you seen the movie ‘Interstellar’? because there they fly into a black hole and i heard that it is quite probably that it a black hole really looks like the one in that movie! if you like black holes it is definitely a movie you should watch.

cheers,
Bas