University of Cambridge study challenges comet theory of life origins

A new study led by the University of Cambridge, published in Scientific Reports, challenges the long-held scientific theory that comets delivered the essential organic molecules required for life on Earth.

Using advanced computer simulations, researchers led by Dr. Richard Anslow from the Institute of Astronomy analyzed the survival of hydrogen cyanide (HCN), a critical prebiotic molecule. The simulations, which included 100,000 comet impact scenarios, suggest that comets typically travel at excessive speeds and enter the atmosphere at angles too steep to allow fragile organic molecules to survive. The intense heat from such impacts would likely vaporize these compounds upon contact.

The research indicates that even in rare instances where molecules might survive the initial collision, they would likely fail to reach the concentrations necessary to spark biological processes. The study concludes that the successful delivery of life-sustaining materials via comets would have been a “one-in-a-million” occurrence rather than a consistent planetary process. Scientists suggest that the chemical precursors to life may instead have originated through internal terrestrial processes or via constant asteroid impacts.