The Origin of the Earth

Planetary Formation and the Origin of the Earth

In the previous section it was shown that matter in the form of the chemical elements formed during the process of star formation. In this section we discuss the processes whereby this early-formed matter is assembled into planetary bodies. A key concept here is the process of accretion — the progressive growth of larger bodies from smaller fragments. Thus the 'story' of planetary formation is one in which a very large number of small particles becoming progressively transformed into a small number of larger bodies, which eventually become planets.