What can we learn from asteroids?

There are two main types of flying space rock – comets and asteroids – and their differences stem from their composition. Comets tend to be ‘dirty snowballs’ of ice and rock, whilst asteroids are composed of a combination of rock and metal.

At the most basic level, asteroids are small, rocky chunks of debris floating through space. Ranging in size from small boulders to giant behemoths hundreds of miles in diameter, they are believed to be the debris of proto-planetary collisions during the violent formation of our solar system. The majority of asteroids we can observe are found in the asteroid belt between Mars and Jupiter, but there is evidence of frequent asteroid impacts on Earth.