Date: Winter 2013-14
I have read about Super-Earth planets and I wonder what would gravity be like on those planets. If an earth-like planet was 5x (volume) larger than Earth, would it have a greater gravity to go along with its size or would it be entirely possible that the planet would be able to have a similar gravitational pull to Earth?
Assuming that the Super-Earth has the same density as Earth, then increasing its volume 5x will also increase its mass 5x. This would then mean that the force due to gravity would also go up 5x (Since force due to gravity = mass of the object x acceleration due to gravity). So this would all depend on whether the Super-Earth has the same density. For example, Jupiter has a density that is about 1/4 that of Earth. So even though Jupiter has a volume that is 1300x that of Earth, it's mass is only 300x that of Earth.
Greg (Roberto Gregorius)
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