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Response to Confusious (Reply #7)

Sun Nov 11, 2012, 11:25 AM

8. It'd actually be a lot less than that

Density and physical size determine surface gravity more than mere mass on those scales. Assuming it's rocky and made of roughly the same stuff as Earth, you'd have a planet with a little under twice the diameter and would be looking at about 1.96 gravities on the surface.

If it was the same diameter as Earth, which it absolutely certainly isn't, then you'd get seven gravities on the surface. If it was half as dense as Earth somehow, the surface gravity would actually be lower than here despite all the extra mass. It can lead to some pretty odd things; Jupiter's over three hundred Earth masses, but its gravity at what people define as its equivalent to "the surface" is only 2.58 g.

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LongTomH Nov 2012 OP
Maven Nov 2012 #1
krispos42 Nov 2012 #6
Deep13 Nov 2012 #2
NoOneMan Nov 2012 #3
wrath of medusa Nov 2012 #4
d_r Nov 2012 #5
Confusious Nov 2012 #7
LineLineNew Reply It'd actually be a lot less than that
Posteritatis Nov 2012 #8
Confusious Nov 2012 #9
toddmiller Nov 2012 #10
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