Asteroids, also called minor planets or planetoids can be thought of as what was left over after the Sun and all the planets were formed.
There is a difference between asteroids and meteors, and that is that a meteor is much smaller than an asteroid. There is also a big difference between asteroids and a comet and that is their appearance, if a comet is close enough to the Sun you can see a coma (fuzzy appearance) and a tail.
The Asteroid Belt
Most of the asteroids in our solar system can be found orbiting the Sun between the orbits of Mars and Jupiter. This area is sometimes called the ‘asteroid belt’. Sometimes asteroids collide into other asteroids and then break into much smaller asteroids. Scientists believe that asteroids are the result of a collision between larger rocky space bodies.
Asteroids can be a few feet to several hundred miles wide. The asteroid belt probably contains at least 40,000 asteroids that are more than 0.5 miles across.
If an asteroid is captured by the gravitational pull of a planet, the asteroid can be pulled out of the belt and go into orbit as a moon of the planet that pulled on it.
During the 18th century, astronomers were fascinated by a mathematical expression called Bode's law. It appeared to be able to predict the whereabouts of known planets, with only one exception…
Bode’s law suggested that there should be a planet between Mars and Jupiter. When Sir William Herschel discovered Uranus, the seventh planet, in 1781, at a distance that corresponded to Bode's law the excitement about this mathematical expression reached an all-time high.
At the end of the century, a group of astronomers had banded together to use the observatory at Lilienthal, Germany, owned by Johann Hieronymous Schröter, to hunt down the missing planet. They called themselves the 'Celestial Police'.
Despite their efforts they were beaten by an astronomer called Giuseppe Piazzi who found it on New Year’s Day.
It was named Ceres...