What were the conditions like on early Earth? (Be specific)

- For decades, scientists believed that the atmosphere of early Earth was highly reduced, meaning that oxygen was greatly limited.

- Such oxygen-poor conditions would have resulted in an atmosphere filled with noxious methane, carbon monoxide, hydrogen sulfide, and ammonia.

- The dense early atmosphere, dominated by the "greenhouse gases" carbon dioxide and water vapor, trapped the radiation of the early Sun, while the solid crust radiated volcanic heat from the interior.