A huge nebula condensing under its own gravitation attraction

contracting, rotating

flattening into a disk, with the Sun forming in the center and eddies gathering up material to form planets. As the Sun contracted and began to visibly shine

intense solar radiation blew away unaccreted gas and dust until finally,

the Sun began burning hydrogen and the planet completed their formation

Early Earth was probably of uniform composition and density throughout.

Heating of the early Earth reached the melting point of iron and nickel, which, being denser than silicate minerals, settled to Earth's center. At the same time, the lighter silicates flowed upward to form the mantle and the crust.

In this way, a differentiated Earth formed, consisting of a dense iron-nickel core, an iron-rich silicate mantle, and a silicate crust with continents and ocean basins.