History of the Earth

By kelly.wong
  • 4600 BCE

    Start of Solar System

    The solar system began as a rotating cloud of stardust (a cloud made up of hydrogen, helium, and dust). Supernova, nearby star, exploded and sent shock waves through the cloud, and caused it to collapse.
  • Period: 4600 BCE to 4590 BCE

    Primary Accretion Stage

    Between 0 and 100,000 years after the solar system formed, our cloud is flattened into a swirling disk. A protostar forms in the center. Deep within the disk, clumps of dust are heated into chondrules (molten rock). These molten rocks clump together and grow into asteroids and planetesimals, eventually becoming planet embryos.
  • 4530 BCE

    Formation of the Moon

    An asteroid the size of Mars smashed into Earth. The huge amount of energy from the impact melted both the Earth and the asteroid. Material from both Earth and the asteroid was thrown out into orbit, which over time, combined to form our Moon. The collision happened about 70 million years after Earth formed.
  • 4500 BCE

    Formation of Earth's Core and Crust

    Different materials in a region of space collided and made a planet. All of the collisions caused Earth to heat up, which melted rock and metal. The molten material separated into layers– gravity pulled the denser material into the center, and the lighter elements rose to the surface.
  • Period: 4500 BCE to 4000 BCE

    Late Accretion Stage

    Between 100 million and 600 million years after the solar system formed, Pluto-like asteroids crashed into Earth and other planets, and deposited metals to the surfaces of these planets.
  • Period: 4000 BCE to 3800 BCE

    End of Heavy Bombardment

    Between 600 million and 800 million years after the solar system first formed. Jupiter and Saturn migrated towards the Sun, creating ripples in the asteroid belt and clearing out many smaller rocks. During this, comets carrying water hit Earth and created the existence of water.
  • 3000 BCE

    Planetary Cooling

    About 1.6 billion years after the Sun was formed, Earth gradually cooled down and the heat in the Earth's core tried to escape. As heat tried to escape, it broke up sections of the earth’s crust and created tectonic plates (continents) and magnetic fields.