Did comets bring the ingredients for life to Earth, according to Cambridge researcher Richard Anslow?

Dr Richard Anslow, lead author of a University of Cambridge study, said probably not intact. Comets are rich in carbon- and nitrogen-bearing molecules, but computer models of impacts show most of those fragile molecules were destroyed as comets struck Earth at tens of kilometres per second and were heated to tens of thousands of degrees. He suggested carbon-rich asteroids or chemistry on the early Earth itself as alternative sources.

• Candidate sources include carbonaceous chondrites, carbon-rich asteroids found between Mars and Jupiter.
• Volcanoes or surface hydrothermal vents could have produced the molecules locally, with no need for impacts.
• Anslow said the result narrows the search for where hydrogen cyanide on early Earth came from.

▸In their words

“the majority of these fragile molecules were largely destroyed as these comets struck the Earth at tens of kilometers per second.” Richard Anslow · at 28:16 — open in the transcript →

Source: our own transcription of the episode. The full conversation is on Global News Podcast (2026-10-29). Read the whole episode summary →

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