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Superluminal
2010-May-11, 04:09 AM
How much would a two hundred pound person weigh on a five earth mass terrestrial planet?

EDG
2010-May-11, 05:39 AM
Depends on the radius of the planet, which would be determined by its composition. At one extreme, a dense rocky planet (density 6500 kg/m) with five earth masses would have a radius of about 10,300 km and a surface gravity of 1.91g, so he'd weigh 1.91 times more than on Earth.

At the other extreme, a low density panthalassic world (density 3500 kg/m) with a rocky core and several earth masses of water and volatiles around it) of the same mass would have a radius of about 12,700 km and a surface gravity of 1.26g, so he'd weigh 1.26 times more than on Earth there.