Abiogenesis

Abiogenesis is the idea that life originated and developed from simple inorganic molecules billions of years ago. Abiogenic non-living compounds developed into more complex molecules that grew increasingly complex and eventually evolved into simple 'living' organisms. The Miller-Urey experiment in the 1950s was able to produce organic living molecules from inorganic components (methane, water, hydrogen, ammonia) which were similar to the ones present on Earth billions of years ago. Abiogenesis is believed by many scientists to have occurred multiple times on Earth and is an area of interest to extraterrestrial life researchers.