Pluto is still active four and a half billion years into its history. It was expected that small planets like Pluto would cool off long ago and not still be showing geological activity. Pluto is, in fact, showing numerous examples of geological activity on a massive scale across the planet.

Alan Stern

Alan Stern

Across Active Activity Billion Cool Examples Expected Fact Four Geological Half History In Fact Like Long Massive Numerous Off Planet Planets Pluto Scale Showing Small Still Would Years

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