The asteroid belt is an area of the solar system between Mars and Jupiter. It is made up of fragments of dust and rock, known as asteroids and dwarf planets.
The asteroid belt sits between the orbits of Mars and Jupiter and is made up of fragments of rock and dust. The belt is not very densely populated, so spacecraft can easily pass through. Johannes Kepler predicted that between Mars and Jupiter there should be a planet. He thought this due to the large gap between the orbits of the two planets.The various objects that make up the asteroid belt are held in place by the Sun’s gravitational pull. The reason the matter formed into a belt and not into planets is thought to be due to the gravitational effects of Jupiter.
The largest object in the asteroid belt is Ceres, a dwarf planet, which makes up roughly one third of the total mass of the asteroid belt. Giuseppe Piazzi discovered Ceres and named it after the Roman goddess of agriculture.
The first spacecraft to go through the asteroid belt was Pioneer 10 in 1972 on its way to Jupiter.