History of the Earth
14.54 billion years ago: the Earth forms
Earth and the other rocky planets formed through violent collisions between planetesimals. The core formed rapidly as heavy elements filtered down through the mantle towards the centre of the planet, while bombardment continued to spread metallic elements across the surface.
24.5 billion years ago: origin of the Moon
The Moon formed 50 to 100 million years after the Earth. The most popular current theory for the Moon’s formation involves a substantial part of the mantle being blasted away from Earth by a giant impact, but some argue that this impactor should have left geological traces that have not been found.
34.1 to 3.8 billion years ago: Late Heavy Bombardment
Earth and the inner planets were hammered by a torrent of high-energy impacts that left their surfaces heavily cratered. This
