Juptier's moons are much smaller than Earth. The largest ones have a diameter around 1/8 that of Earth, meaning they are 1/512 the size of Earth.
I love people who know these formulas off the top of their head. Size in the above example = volume? Unless the planet is hollow the most interesting measure is surface area. What is the surface area of a planet 1/8 the diameter of earth? This tells us how much space their is to ranch, mine and ride ATVs on!! Earth = 1 Earth Surface Area. How big is Mars? Please show your work so I can learn the formulas. Thanks.