Hadean Eon

Formation of Sun (4,680 to 4,630 Ma).

Formation of Earth (4,570 to 4,567.17 Ma), Early Bombardment Phase begins.

Formation of Moon (4,533 to 4,527 Ma), probably from giant impact, since the end of this era.

Possible first appearance of plate tectonics. This unit gets its name from the lunar geologic timescale when the Nectaris Basin and other greater lunar basins form by big impact events. Earliest evidence for life based on unusually high amounts of light isotopes of carbon, a common sign of life.

End of the Early Bombardment Phase. Oldest known mineral (Zircon, 4,404 ± 8 Ma).

Indirect photosynthetic evidence (e.g., kerogen) of primordial life. This era overlaps the beginning of the Late Heavy Bombardment of the Inner Solar System, produced possibly by the planetary migration of Neptune into the Kuiper belt as a result of orbital resonances between Jupiter and Saturn. Oldest known rock (4,031 to 3,580 Ma).