Haydean

In the beginning, God created the heavens and the Earth. The earth was without form and void, and Darkness was over the face of the deep. The spirit of God was hovering over the face of the waters. And God said Let there be light and there was light. And God saw that it was good. God called the light day and the darkness Night; there was evening  and morning, the first day.

And God said, "Let there be an expanse, in the midst of the waters, and let it separate the waters from the waters, and god made the expanse and separated the waters from the waters" that were under the expanse from the waters that were above the expanse, and it was so. And god called the expanse heaven, and there was evening and there was morning, the second day. 

The  Haydean eon began with the accretion of the Earth from the gas and dust in the solar system. It also saw the formation of the Moon around 4.5 billion years ago, likely from a collision with a Mars-sized protoplanet called Thea. 

The Hadean Eon is the first of four eons in Earth's history, with the Archean, Proterozoic, and Phanerozoic eons following. It was formally ratified as a geological eon by the International Commission on Stratigraphy in 2022, with the Hadean Eon being Earth's first and oldest eon, spanning from about 4.6 to 4.0 billion years ago, known for its hellish conditions.  The conditions were extremely hostile, with the surface being a "magma ocean" due to the heat of formation, radioactive decay, and continuous bombardment by asteroids and comets. It was a chaotic and violent period marked by constant asteroid impacts and Frequent volcanic eruptions were also common, releasing gases and water vapor that contributed to the atmosphere and eventually the oceans. 

As the planet cooled, denser materials like iron sank to form the core, and lighter silicates rose to create a primitive, constantly changing crust—a thick, carbon dioxide-rich atmosphere formed as water vapor condensed. Although no intact rocks remain, microscopic zircon crystals, some dating back to 4.4 billion years ago, provide indirect evidence of a cooling crust, the presence of liquid water, and potentially even the formation of early continents. 

At the same time, very little direct evidence of this time remains; the oldest known mineral grains (zircon crystals) suggest the presence of some stable surface conditions with liquid water by 4.4 billion years ago, paving the way for the formation of continents in the subsequent Archean Eon and the formation of the Earth and Moon from a cataclysmic collision.