What if Earth were the size of Jupiter? What would be different about life as we know it?
Increased gravity for one thing...
Jupiter is roughly
If the Earth were the size of Jupiter but still the same density as it is now, then gravity would be
The atmosphere would probably be considerably denser as a result of the increased gravity. I am not sure whether that would tend to increase or decrease the temperature at the surface. Would it reflect more of the sun's energy back into space before it reached the ground or would it generate a stronger greenhouse effect? If the latter then the surface could be considerably warmer than we experience.