The earliest eon in the history of the earth, from the time of the accretion of planetary material, around 4600 million years ago (mya), to the date of the oldest known rocks—and hence the beginning of the geological record—about 4000 mya. The young earth was probably a rocky planet with a hot interior and a moist surface with oceans of liquid water. No evidence of life has been found. The Hadean eon precedes the Archaean eon.