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From: cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!watserv1!watdragon!watyew!jdnicoll@tut.cis.ohio-state.edu (Brian or James)
Subject: Re: Why we would need a planet.
Using the Earth for industrial raw materials is probably going to irk the
population still using it as a homeland. There could well be more people living
in non terrestrial habitats in a millenium or so (Although I doubt it myself, if
the "It's raining chicken soup" crowd is correct about the wealth of NT
habitat cultures. Rich people don't have kids.) but if there *are* more Habitat
types than terrans, I would bet that most of the significant population growth
occured because of habitat birth rates rather than the hordes of terrans
emigrating up the gravity well. The logic of totalling the planet to make way
for a 'higher' civilization may not be as self obvious to people who have
lived their entire lives on a planet as it is to orbiting foreigners looking
for a few decades of fast growth material. It's a lot like North Americans telling England "So sorry, but we're going to grind up Great Britain because we need the raw materials to feed our Detroit car factories. Hope you don't mind
moving" or Japan saying the same to North America. A perfectly logical point of
view, but only for people who don't come from the place they want to destroy.nd as I said earlier, most people's kids probably won't get to go upstairs.
There are also places that are regarded as holy ground even for those
who don't live there. How likely is it that space living Islamics would consent
to dismantling Mecca?
James Nicoll
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Date: 19 Feb 90 00:56:13 GMT
From: rochester!dietz@rutgers.edu (Paul Dietz)
Subject: Re: Why we would need a planet.
In article <9002182053.AA12315@aristotle.jpl.nasa.gov> pjs@ARISTOTLE-GW.JPL.NASA.GOV (Peter Scott) writes:
>>Jupiter and the Sun have deeper gravity wells (and lots of fairly
>>useless hydrogen and helium).
>
>This has to be the first time I have heard Paul Dietz refer to hydrogen
>and helium as "useless"... :-) Isn't it much more likely that this
>future civilization will use these two elements for power generation and
>possibly large-scale transmutation? You were proposing dismantling the Sun,
>that's a considerable gravity well and amount of hydrogen and helium!
Well, I was thinking of raw materials for building structures. Hydrogen
and helium are, by themselves, pretty useless for that (although
compounds containing hydrogen might very well use material mined from
the outer planets at that point).
Large scale transmutation would necessarily involve even more energy
than mining matter from the sun, so (by that measure) would be less
practical.
Transmutation does look to me to be feasible for making some rarer
isotopes, though, even with current physics, given a sufficiently
large spacefaring civilization.
>If the BIS Daedalus Project considered that the cheapest way to get He3 for
>their Barnard's Star probe was to mine it from Jupiter, this planet-munching
>culture should be capable of scaling up the same operation.
3He is a special case, since the earth has almost none of it. The
alternative in the Daedalus Project study was to make the 3He by
nuclear reactions. The situation is reversed for heavy elements: on
Earth they can be stripped from the surface, while on Jupiter they are
