Asteroids

Asteroids are small objects not as big as planets, consisting of mineralic rocks. Sometimes Asteroids are called Planetoids, to show that they are significally smaller than planets. Most of them are shaped irregularly.

There is a large Sphere of Asteroids between the inner and the outer planets between Mars and Jupiter, called the Main Asteroid Belt, or sometimes called Main Belt or simply Asteroid Belt. It is believed that the Main Belt is the remainder of pre-planet era when the formation of the Solar System has begun. The formation of a planet in this zone was maybe prevented by gravitational effects induced by Jupiter. All Asteroids of the Asteroid Belt together have only 4% of the mass of our Moon - the largest Asteroid 1 Ceres holds on third of this mass alone.

The largest Asteroids are 1 Ceres with diameters of 975×909 km, 4 Vesta with diameters of 578×560×458 km, 2 Pallas with diameters of 570×525×500 km, 10 Hygiea with diameters of 500×385×350 km and 511 Davida with a diameter of around 326 km.