Planetary Size Quotes

“Heat escapes from small planets more easily than from large planets, because small planets have a greater ratio of surface area (through which heat escapes) to volume (which stores heat and generates it by radioactive decay). A small planet would require a much greater amount of radioactive heat generation, per kilogram of rock, to maintain vigorous lava-producing volcanism. This is basically for the same reason that a mouse needs to consume many more calories per gram of body weight than a human. A typical mouse, weighing 40 grams, consumes 10 kilocalories (sometimes called simply ‘calories’ in everyday usage) per day. Scaled up to the mass of a human, that would amount to 25,000 kilocalories a day—equivalent to 7kg of dry spaghetti.”
― Raymond T. Pierrehumbert, Planetary Systems: A Very Short Introduction