Between the orbits of Mars and Jupiter there is a region of 550 million kilometers in which about 20,000 asteroids orbit. Some even have satellites around them. Is the Asteroid belt.
The asteroids were first discovered theoretically, as happened with the discovery of Neptune and Pluto. In 1776, the German astronomer Johann D. Titius predicted the existence of a planet between Mars and Jupiter.
In 1801 Giuseppe Piazi discovered a celestial body orbiting the distance predicted above. The size of the object, baptized as Ceres, it was smaller than expected (1025 kilometers), so it did not completely fit the proposed model. A year later, Heinrich Olbers (1758-1840) discovered another asteroid of similar characteristics: Shovels.
In 1807, Heinrich Olbers suggested that, instead of an intermediate planet, there be more residual bodies from a much larger planet. Today we know that this was not so, but that these asteroids are bodies that were not added during the beginning of the Solar System to form a planet, possibly due to the enormous gravitational force of nearby Jupiter.
The ships that have traveled through the asteroid belt have shown that it is practically empty and that the distances that separate from each other are enormous. The probability of finding one is minimal.
The asteroids of the belt formed, according to one theory, from the destruction of a planet, a small planet. It would be necessary to gather 2,500 times the known asteroids to have the mass of the Earth.
According to another theory, a group of about 50 asteroids formed with the rest of the Solar System. Afterwards, the collisions have been fragmenting them.
Inside the belt there are lagoons, areas where no asteroid spins, because of the influence of Jupiter, the nearest giant planet.
The calls Trojan asteroids they are located in two clouds, one that rotates 60 ° ahead of Jupiter, in the plane of its orbit, and the other 60 ° behind.
The spatial distribution of asteroids is conditioned by the presence of Jupiter. The gravity of this giant planet creates resonant areas where asteroids accumulate, such as Trojans.
In the image you can see the asteroid Castalia photographed by the Hubble Space Telescope in 12 positions