Precambrian/Hadean

The Hadean Eon started with the formation of the Earth and the Moon and lasted around 4 GYA.

A recent study theorized that the heavy bombardment during the Hadean eon brought either life or the building blocks to life to Earth: meteors from this bombardment may of had phosphorus material, which a building block for life. There is speculation that the earth was covered in water, and wasn't molten during this time: this eon was named after hellish conditions, as it was thought Earth was a molten planet at this time. Rocks formed during the Hadeon Eon were formed under a relatively low temperature that suggests there was water on the planet to keep temperatures steady.

The Hadean is comprised of three eras: Paleohadean, Mesohadean, and Neohadean. The Prenectarian and Nectarian periods are the Moon's corresponding time frame.

Prenectarian period
The Prenectarian period lasted from the creation of the Earth and moon 4,533 MYA until 3,920 MYA.

Nectarian period
The Nectarian period was from 3,920 MYA ago to 3,850 MYA. This is the time after the heavy bombardment.