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Cambridge study on comet theory of life origins

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2026-10-31 10:35 UTC → 2026-11-01 07:06 UTC · added ~~removed~~

Researchers at the University of Cambridge, led by Dr. Richard Anslow of the Institute of Astronomy, have published a study in Scientific Reports that challenges the theory that comets delivered essential organic molecules to early Earth. Using computer simulations of 100,000 comet impact scenarios, the study suggests that comets typically enter the atmosphere at speeds and angles that would vaporize fragile prebiotic molecules, such as hydrogen cyanide, upon impact. The research concludes that while comets contain necessary carbon- and nitrogen-containing molecules, the successful delivery of these materials would be a “one-in-a-million” occurrence or a “one-off fluke” rather than a consistent process. Focusing on the panspermia hypothesis, which proposes that organic molecules were transported to Earth via cosmic bodies, the simulations specifically examined hydrogen cyanide due to its role in synthesizing lipids, sugars, and nucleotides. Anslow described the long-standing notion of comets acting as cosmic delivery systems as “a romantic idea” that is ultimately “very unlikely” according to the new modeling results. ~~Additional~~ New data from the simulations indicates that in 54 percent of the scenarios, no successful delivery occurred. Even in the rare instances where delivery was successful, researchers noted that concentrations were likely insufficient to trigger prebiotic chemistry. While the findings ~~indicate~~ cast doubt on the role of comets for Earth, researchers noted that ~~comet impacts declined rapidly during Earth’s first 500 million years, further limiting opportunities~~ conditions on Mars might have been more favorable for ~~prebiotic delivery.~~ such delivery due to its smaller size and thinner atmosphere. The research suggests that the chemical precursors to life may have instead originated through asteroid impacts or internal terrestrial processes.

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