Did Harold Urey believe life originated in space?
That is a common misconception. I never argued that life itself came from space. What I proposed was that the organic building blocks of life—amino acids, nucleotides, and similar compounds—could form naturally on the primitive Earth through chemical reactions driven by energy sources like lightning or ultraviolet light. The Miller-Urey experiment demonstrated this directly. Some have misinterpreted this as support for panspermia, the idea that life arrived from elsewhere, but I always maintained that the origin of life is a problem of chemistry, not astronomy. The evidence points to an Earth-based chemical evolution: simple molecules in the early atmosphere and oceans, energized by natural forces, produced increasingly complex organic compounds until self-replicating systems emerged. We must look to chemistry for answers, not invoke extraterrestrial intervention.
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