Historical perspective

Based on the available evidence, scientists have reconstructed detailed information about the planet's past. Earth is estimated to have formed approximately 4.55 billion years ago out of the solar nebula, along with the Sun and other planets. The moon formed relatively soon afterwards.

Initially molten, the outer layer of the planet cooled, resulting in the solid crust. Outgas sing and volcanic activity produced the primordial atmosphere. Condensing water vapor, augmented by ice delivered by comets, produced the oceans. The highly energetic chemistry is believed to have produced a self-replicating molecule around 4 billion years ago.

Continents formed, then broke up and re-formed as the surface of Earth reshaped itself over the course of hundreds of millions of years, occasionally combining to make a super continent. Roughly 750 million years ago, the earliest known super continent Rodinia, began to break apart. The continents later recombined to form Pannotia which broke apart about 540 million years ago, then finally Pangaea, which broke apart about 180 million years ago.