Miller-Urey hypothesis

Miller-Urey hypothesis: A new study adds another angle to the much-disputed Miller-Urey hypothesis, suggesting that water sprays alone could generate organic compounds without needing external electricity.

• The study, titled ‘Spraying of water micro-droplets forms luminescence and causes chemical reactions in surrounding gas’, was published in the journal Science Advances.
• About Miller-Urey Hypothesis: Proposed by Stanley Miller and Harold Urey in 1952.

o Suggests that life on Earth emerged from a lightning strike.

• Experiment: Applied electricity to a mixture of water and inorganic gases (methane, ammonia, hydrogen), leading to the formation of organic compounds (like amino acids).
• Significance: Provided one possible explanation for the origin of life on Earth.

• Criticism: Real lightning would have struck infrequently, mostly over open oceans, where organic compounds would quickly disperse.
• New Study Findings: Water sprays alone can generate organic compounds without external electricity, led by Stanford University chemist Richard Zare.
• Experiment: Spraying water into a mixture of nitrogen, methane, carbon dioxide, and ammonia resulted in the formation of organic compounds like hydrogen cyanide, glycine, and uracil.
• Implication: Crashing waves or waterfalls on early Earth could have triggered the chemical reactions necessary for life, providing an alternative to the lightning-based Miller-Urey hypothesis.