HADEAN

4.56 BILLION -3.8 BILLION: HADEAN

An artistic rendering of the Hadean Earth when the rock fragment was formed. Impact craters, some flooded by shallow seas, cover large swaths of the Earth’s surface. The excavation of those craters ejected rocky debris, some of which hit the Moon. Credit: Simone Marchi. (NASA Science)

    • Formation of the Earth;
    • A huge planetoid crushes into Earth & splits off Moon;
    • Massive meteor bombardments pound Earth and Moon;
    • Interior of the molten Earth separates into layers;
    • Dense, very hot atmosphere of hydrogen, CO², steam, ammonia & methane – no oxygen;
    • Boiling steam begins to condense into oceans;
    • Earliest known rocks on Earth date from the Hadean;
    • Old earth rock found on moon – Apollo 14 – The rock crystallized about 20 kilometers beneath Earth’s surface 4.0-4.1 billion years ago;
    • Organic chemical components of the building blocks;
      of life (amino acids, RNA and DNA) first appear.