History of the Earth Timeline

By Mayo.
  • 9600 BCE

    9.6 billion years ago – Milky Way Formation

    9.6 billion years ago – Milky Way Formation
    Less than a million years after the Big Bang, the first small galaxies were born, made of hydrogen clouds, stars, and dark matter. Gravity pulled these galaxies together, growing them. Star clusters came together to form the galaxy’s core, and as the gas clouds rotated faster, the galaxy flattened out into a disk.
  • 5600 BCE

    5.6 billion years ago – Star Death and Rebirth

    5.6 billion years ago – Star Death and Rebirth
    As old stars collapsed and exploded, there were new stars, formed from the elements blown out by the supernova explosions. It is from the process that our sun was formed.
  • 4600 BCE

    4.6 billion years ago – Planetary Accretion

    4.6 billion years ago – Planetary Accretion
    Around the newborn sun, smaller concentrations of solid material gradually grew into larger bodies through repeated collisions, eventually forming a network of planets, and among them was our Earth.
  • 4500 BCE

    4.5 billion years ago – Formation of the Moon

    4.5 billion years ago – Formation of the Moon
    Debris left over from the formation of the solar system - a Mars-sized asteroid named Theia – collides with Earth, and the debris from this crash, over time, forms into the spherical object we now know as our moon.
  • 4000 BCE

    4 billion years ago – The “Iron Catastrophe”

    4 billion years ago – The “Iron Catastrophe”
    Earth’s core was formed during the pivotal event called the “Iron Catastrophe”. Which was when the planet heated past metals’ melting points, and heavy metals gravitated towards the center of our planet. With this, lighter elements, mostly silicates, was “squeezed” out and emerged as the early mantle and crust.
  • 3800 BCE

    3.8 billion years ago – End of Heavy Bombardment

    3.8 billion years ago – End of Heavy Bombardment
    The period Late Heavy Bombardment (LBH), also known as the lunar cataclysm because the first evidence of the LHB was found on the moon, refers to the series of frequent collisions that affected the inner solar system.
  • 3700 BCE

    3.7 billion years ago – Planetary Cooling

    3.7 billion years ago – Planetary Cooling
    Tides (much stronger than the ones we’re familiar with today), formed due to the mutual attraction of the Earth and the moon, and through its constant stirring allowed for the mantle to lose heat. This energy loss was also making the moon gradually pull away, which made tides progressively weaker and so the molten rocks were being stirred less and less, resulting in Earth’s mantle beginning to solidify.