Earth’s history (The first billion years )

Planetary accretion

4567 BCE

Ar this stage, Solar System was a disk of dust and gas in orbit around the proto-Sun. The solid materials collided with each other and accreted to form gradually larger bodies because of gravity. Gradually, Earth and the other three terrestrial planets were formed.

Core formation

4500 BCE

The stage where core started to form. Earth's rocky core formed first, with heavy elements colliding and binding together. Dense material sank to the center, while the lighter material created the crust. Gravity captured some of the gases that made up the planet's early atmosphere.

Formation of the moon

4490 BCE

Earth suffered a collision by a large Mars-sized planet. The debris of the collision drew together due to the gravity and form the moon, which started orbiting around Earth.

Planetary Cooling

4300 BCE

At this stage, the temperature decreased and Earth turned to solid.

End of heavy bombardment

3800 BCE

Early Earth suffered a constant threat of attack from leftover planet-building material. From about 4.5 to 3.8 billion years ago, failed planets and smaller asteroids slammed into larger worlds, scarring their surface. After this stage, there was no more heavy bombardment to Earth.