What are: Black holes | Earth, Solar System and Universe.

The so-called black holes are bodies with a very big, huge gravitational field. Cannot escape no light or electromagnetic radiation, why are black. They are surrounded by a spherical "border" that allows light between but not exit.
There are two types of black holes: bodies of high density and low mass concentrated in a very small space, and bodies of low density but very large mass, as in the centers of galaxies.
If the mass of a star is more than two times that of the Sun, comes a time in your cycle that not only neutrons can withstand gravity. The star collapses and becomes a black hole.

Stephen Hawking and the light cones

The British scientist Stephen W. Hawking has devoted much of his work to the study of black holes. In his book History of time explains how, a star that is collapsing, the light cones that emit begin to sag in the surface of the star.
To be small, the gravitational field grows and light cones are inclined more and more, until they can't hide. The light turns off and turns black.
If a component of a binary star becomes a black hole, taking his partner material. When Eddy comes to the hole, he moves so fast that it emits x-rays. So, although you can not see, it can be detected by their effects on nearby matter.
Black holes are not eternal. Although no radiation does not escape, it seems that they can do it some Atomic and subatomic particles.
Someone who observed the formation of a black hole from the outside, would be a small, red star until, finally, it would disappear. Its gravitational influence, however, would remain intact.
As happened in the Big Bang, a singularity, i.e. physical laws is given also in black holes and the predictive power fail. As a result, any outside observer, if any, could see what happens inside.
The equations that attempt to explain a singularity, as it occurs in black holes, have to take into account the space and time. The singularities are always located in the past of the observer (such as the Big Bang) or in the future (such as gravitational collapses), but never in the present. This curious hypothesis is known by the name of cosmic censorship.

Translation for educational purposes authorized by: Astronomía: Tierra, Sistema Solar y Universo