Scientists Pinpoint When Early Earth Became Habitable: 4.33 Billion Years Ago

A study in Nature Communications estimates that conditions for an RNA world emerged about 4.33 billion years ago, once asteroid bombardment eased and Earth's crust cooled. The 3D model by Oleg Abramov's team at the Planetary Science Institute simulated crustal heating and RNA thermal stability.

• Optimal conditions for an RNA world arose around 4.33 billion years ago
• The model covers 4.5 to 3.5 billion years ago
• The estimate matches zircon evidence of liquid water 4.4 billion years ago
• RNA chemistry also requires water, reduced nitrogen and suitable local conditions