CHAPTER 4. Unveiling Early Earth Photochemistry Through Experimental Simulations of Planetary Atmospheres

This chapter summarizes the contributions of the early Earth atmosphere between late Hadean and early Archean eons (4.3 to 3.7 Ga) to sustain the emergence of life: influencing both the climate and prebiotic chemical synthesis through photochemistry. Almost no geological constraints remain on these early ages so that chemical scenarios are largely explored through experimental simulations. The main scientific results through time are given, from the pioneering experiment by Miller and Urey in the 1950s, up to the most recent studies focusing on high altitude photochemistry.