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Old May 23rd 09, 08:47 PM posted to sci.space.policy
Fred J. McCall[_3_]
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Default Europe, Russia discuss 'orbital shipyard' plans

Marvin the Martian wrote:

:On Fri, 22 May 2009 12:43:55 -0700, Fred J. McCall wrote:
:
: Marvin the Martian wrote:
:
: :On Fri, 22 May 2009 12:30:11 -0400, Len Lekx wrote: :
: :
: : Correct me if I'm wrong... but doesn't light behave according to
: : inverse-square laws...? Since Mars is twice as far away (roughly)
: from : the sun as we are, doesn't that mean that solar energy is
: one-quarter : the intensity?
: :
: : Or am I just plain confused? :-) :
: :Earth is, of course, 1 AU away.
: :Mars is about 1.4-1.6 AU away. Say, 1.5 AU. :
: :So, (1 AU)^2 / (1.5 AU)^2 = 1/2.25 = .44 or 44% :
: :McCall is about right when he says you get twice the solar energy on
: the :Moon as you do Mars. And it is true solar energy will work better
: on the :moon than it does on earth. The problem is, you'd have to haul
: up all :that solar energy equipment up to the moon, and you have 2 weeks
: of :darkness at a time, so you're going to need some really big
: batteries if :you're going to build a base there.
: :
:
: Nonsense. If your head wasn't so firmly up and locked you'd think of
: these things yourself, since they're pretty widely known.
:
: Use thermal solar (not photovoltaic) and store energy during the day in
: molten salts and use those for energy during the dark. Very little to
: haul other than reflective film and no batteries.
:
: DOH!
:
: Next?
:
:That "battery" either would be so hot as to radiate too quickly over the
:lunar night, or not warm enough to provide useful thermodynamic work.
:
:A structure is needed to hold the reflective film in something that
:approximates parabolic shape, or the sunlight won't be focused.
:
:This is very far from the "free energy" claimed. So far, the reflector,
:the structure, and the "salts" to melt are needed. You also need a way to
:covert hot salts into useful energy.
:

And all the preceding is very simple physics, indeed. The problem is
your head is so far up your ass and locked that you are incapable of
thought.

--
"Some people get lost in thought because it's such unfamiliar
territory."
--G. Behn