Larger planets will definitely be more active; volume scales up much more rapidly than surface area (by the cube versus the square, respectively IIRC), which is just a roundabout way of saying that more massive "Earths" have more hot mass with less area to cool off with.


In short: just the way a liter of water will cool off much more slowly than a milliliter, so will a more massive terrestrial planet cool more slowly.

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"Call me old-fashioned, but I think fire is magic. And it scares me a lot."

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