13. Deep Hot Biosphere Theory
The Deep Hot Biosphere Theory, proposed by Thomas Gold in 1992, suggests that life originated deep beneath Earth’s surface, where microbial life exists in the Earth’s crust, obtaining energy from chemical sources due to fluids migrating upward from deeper levels. (pubmed.ncbi.nlm.nih.gov) This subsurface life is independent of solar energy and photosynthesis, thriving in high-temperature environments. (pnas.org) Gold’s theory challenges traditional views on the origin of life, proposing that the deep biosphere may be widespread among planetary bodies in our solar system and beyond. (pubmed.ncbi.nlm.nih.gov)