From: Spike Jones (spike66@ibm.net)
Date: Sun Aug 15 1999 - 16:08:43 MDT
> Doug Jones wrote: Zubrin's Mars Direct requires some bravery,
> but not insanity, on the part of the crew.
Yes, Mars Direct. Let me comment on that later.
> Not like the hyperbolic
> rendezvous they were pushing at CFM II.
I heard of that, but was not up on the details.
> That leetle spindly thing massed 14,700 kg- 15 freaking tons to land
> two people on the moon!
Ja, and the point of this is that 15 freaking tons is not enough for
what I have in mind.
> As for mighty rockets, well, that could change fairly soon. Further
> I can't say, due to NDA.
Hope you are right Doug. {8-]
> Nope- hypersonic entry and a parachute get you down to just 100 m/s,
> instead of the 1700 m/s you need to back down from lunar orbit.
True, however once the weight of the parachute is figured in, the
savings are not as dramatic. Your point is well taken that it is
actually easier to soft land stuff on Mars than on Luna. The surface
gravity does not matter much in the delta vee calcs and the
aerobraking available on Mars helps some.
> > Now look at the size of the Roy Wolford's Biosphere experiment.
>
> That is not a good analogy- they tried to put all sorts of cutsie
> biomes in there, instead of concentrating on the simpler task of
> life support.
Ja, I was kinda wondering why they were doing all that. {8-]
> With just chemomechanical water loop closure and
> partial oxygen closure, the consumables are only about 1
> kg/day/person, or a tonne per person for a 1000 day mission. No
> biology other than the crew themselves.
Doug, this is where I part company with most of the Mars people,
for the point of my concept is not to keep a person alive for 1000
days and return. Most of the payload to softland in my scenario
is machinery, designed to build a biome. That is why I suggest
not wasting too much payload on the crew, for the crew is not
the reason for the landing. This crew will not be a group of
explorers! We have autonomous machines that can do that.
The crew will be only for the purpose of repairing and guiding
machines, in their task building structures. Everything that *can*
be done from the earth will be. Everything that actually requires
a realtime human presense will be the task of the single, or
perhaps two young ladies.
I do not dispute your 1 kg/person/day number, in fact I think
with extreme effort we could do even better than this, and I am
in fact suggesting extreme effort.
> Nah- 500 tons in LEO could send a well-supplied 4 person mission to
> Mars (and return). The issue isn't tech, it's money.
Right! Nowthen, the usual 4 person for 3 years and return missions
all seem to lack that wacky notion I had of landing the equipment
from which to bootstrap a foundry of sorts, to start manufacturing
infrastucture for more humans. Altho there is a great deal of exploring
to do, Im suggesting hold off on that for now, and start building
something to live in, and to build more equipment to build more
buildings, all from indigenous materials.
> The key is not to use the shuttle for the project, but use large
> cheap launchers developed for a different (and profitable) market.
OK, so if the financiers can make that happen, we are on our way.
Doug, our payload figures probably are in pretty good agreement.
Our main difference would be what to do once we got there. spike
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