um...darn, we better start writing more SF, because pretty soon we're gonna find out what alien life really is and then SF will be as dated as Barsoom stories!
(The whole "For how long, what effects does it have, yadda yadda yadda" thing. 'cause I'd like to know. NASA's handy for microgravity, but several of the same problems aren't going to happen, and new ones will appear.)
If the composition is identical, then you're right about the mass, but gravity isn't directly proportional to mass and the composition isn't necessarily identical.
Gravity is proportional to mass and the inverse of the square of the distance from the mass - meaning that added radius on the planet reduces surface gravity, just as increased mass adds it again.
(James Nicoll did the 2x math, and I trust his numbers enough that I didn't bother to check them.)
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(no subject)
Date: 2007-04-25 03:02 pm (UTC)(no subject)
Date: 2007-04-25 03:45 pm (UTC)(no subject)
Date: 2007-04-25 07:08 pm (UTC)(no subject)
Date: 2007-04-25 08:27 pm (UTC)Reference?
(The whole "For how long, what effects does it have, yadda yadda yadda" thing. 'cause I'd like to know. NASA's handy for microgravity, but several of the same problems aren't going to happen, and new ones will appear.)
(no subject)
Date: 2007-04-26 01:56 am (UTC)(no subject)
Date: 2007-04-26 02:06 am (UTC)Gravity is proportional to mass and the inverse of the square of the distance from the mass - meaning that added radius on the planet reduces surface gravity, just as increased mass adds it again.
(James Nicoll did the 2x math, and I trust his numbers enough that I didn't bother to check them.)
(no subject)
Date: 2007-04-26 03:40 am (UTC)COLONY!