Know your astroids:

 

These bodies of rocks metals and ice range in size from a few feet across up to six hundred and ten miles in the case of the largest, Ceres.

 

Astroids are often classified according to their spectral type, which has to do with the type of light they reflect.

 

What's at stake: The Space rush

 

The study of meteorites, space rocks that have fallen to earth, reveals a variety of useful materials that could be extracted.