Speculoos-2c: A new potentially habitable earth

Re:Speculoos-2c: A new potentially habitable earth by a3w on Wednesday September 07, 2022 @07:47AM (#32749359)

same density, higher size does not mean 2.5 g. Only some of that mass is below you. Some is to the front, right, back, left, where vectors in sum are zero.

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Re:Speculoos-2c: A new potentially habitable earth by anonymous_sorry on Wednesday September 07, 2022 @08:07AM (#32749516)

Also, all the "extra" mass is further away from you, and gravitation is proprtional to distance cubed. Interesting.

Apparently surface gravity is proportional to mass/radius^2 [0]

Assuming constant density as per the grandparent, the mass increases with the cube of the radius.

Which simplifies to surface gravity being proportional to the radius of the planet.

[0] https://en.m.wikipedia.org/wiki/Surface_gravity

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Re:Speculoos-2c: A new potentially habitable earth by throwawaymaths on Wednesday September 07, 2022 @08:06AM (#32749512)

This is incorrect, the decrease comes from being at a higher altitude from the center of the planet, see gauss' law for gravity. If you kept the altitude the same the force would be exactly proportional as expected.

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