[extropy-chat] MARS: Because it is hardB

Robert J. Bradbury bradbury at aeiveos.com
Tue Apr 13 11:21:03 UTC 2004

On Tue, 13 Apr 2004, Matus wrote:

> "the deltaV required [snip]
> According to Zubrin, it doesn't make much sense to go to the Moon as a
> staging point for a trip to Mars.  I happened to read this page just
> today and came across Robert's question.

This reminds me of the *very* old cartoon with Bullwinkle (the moose)
and Rocky (the flying squirrel?).

Bullwinkle (pretending to be a magician) reaches into a hat and says
"Watch me pull a rabbit out of the hat."  To which Rocky responds
"That trick never works." (Usually he gets a lion or an elephant or
anything that is dangerous but never the rabbit.)

Well today I am Bullwinkle and the ExI-list is the hat and delivered
up exactly the information (aka rabbit) required (thank you Michael).
Pretty damn amazing.

> Zubrin Mars Direct plan has pretty much won me over, does anyone here
> have any objections or counter arguments?  I would be interested in
> hearing some criticisms of his plan.

Zubrin *almost* gets it right towards the end of the book I think
where he suggests hoisting martian material into orbit to build
space power satellites.  The basic criticism is that it makes no
sense to hoist people out of one gravity well to put them at the
bottom of another gravity well.  It is a waste of energy.  Throw
an automated nanofactory down on Mars that can build a space
elevator system (or something equivalent) and dismantle the darn
thing.  If need be dismantle a few asteroids to give you sufficient
matter to store the information content of the first few (hundred?)
meters of the planet [Harvey has to have something to play with when
he retires... :-)].  Then turn the rest of it into material to build
O'Neill space habitats.

If you want the biggest mountain or the deepest canyon simply go
build it in an oversized habitat.  Its little different from the
recent Popular Science article I think I posted on megascale
engineering structures being built on Earth.

For the record people who haven't read [1] the limit on the time to
disassemble Mars (using the energy available) is of the order of 12
hours using the energy we have avaiable.  Though towards the end,
the dissassembly could become rather chaotic and wasteful.  It
might be done faster if a significant number of fusion reactors
were constructed and hydrogen imported from Jupiter/Saturn/comets.
But I haven't calculated the element requirements for that yet
(in part because we don't yet have a working fusion reactor that
I can cite) so I'm not absolutely sure it would be possible in
this solar system.


1. Planet Disassembly

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