Classification of Asteroids

One should however take into account biases in the observations—e.g. dark C-types are more difficult to detect. 

According to their position in the solar system, asteroids can also be categorized into  

The giant outer planets formed from an agglomeration of billions of comets. The comets we observe today are the left over pieces like the asteroids are the left over pieces from the formation of the inner planets (Mercury, Venus, Earth and Mars). 

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