The History of the Earth

Planetary Accretion 4.6 Billion Years Ago

4 BCE

Early on, the solar system started as a nebula, where particles were not absorbed into the Sun and instead swirled around it into a flat disk of dust and gas, held in orbit by the Sun’s gravity. This disk is called an accretion disk. As gravity collapsed the material, the sun began to rise to leave the force of gravity to draw smaller particles together. The solid materials collided with each other and accreted to form gradually larger bodies.

Theia's collision with Earth 4.5 Billion Years Ago

4 BCE

The Moon formed out of the debris left over from a collision between Earth and an astronomical body the size of Mars known as Theia.

Formation of the Moon 4.5 Billion Years Ago

4 BCE

The moon formed when a wandering planet (Theia) crashed into the young Earth. Huge amounts of material were thrown into space, eventually coming together to form the Moon. This 'big splash' theory would explain why the Moon’s rocks are very similar to those on the Earth.

Planetary Cooling 4.5 - 3.8 Billion Years Ago

4 BCE

Planetary cooling formed the planet into a molten planet. Clumps of asteroids,meteors,and comets helped formed the planet into a sphere. There were volcanic eruptions as well which contained magma . The magma then hardened which created Earth's outer core.

End of Heavy Bombardment 3.8 Billion Years Ago

3 BCE

Comet and smaller asteroids slammed into larger planets, scarring their surface.

Core Formation 1.5 Billion Years Ago

1 BCE

The core formed during accretion, as metal from impactor sank through the magma ocean to the center of our planet.