Mars vs. Luna (was; Two books)

>
> Speaking of colonizing moons, it seems that colonizing Phobos may
be
> easy in the short term. There is reason to believe that Phobos is a
> captured asteroid and may contain a large ammount of volitals.
> Without the need of a reentry heat shield, extra propellant for
> decent or long periods of aerobraking makes setting up a colony
much
> easier on Phobos than on the surface.
>

> instead. This would combine the advantages of aerobraking with the
> advantages of being in a much shallower gravity well, and the

Very true. Had forgotten about aerobraking to Phobos.

> As to Mars. It doesn't take much more deltaV to reach Mars than to
> reach Luna. Mars has two huge advantages over Luna.
> One, it has an atmosphere of CO2. A few plants, some inflatable
> clear domes and wham, instant colony.
>
> Yes, but does local availability of Carbon really save you all that
much
> weight? The NASA Summer Study on orbital habitats assumed all
carbon would

Carbon isn't the advantage, it's Oxygen. Extracting O2 is easier
from Martian CO2 than from Lunar mineral oxides. MarsOx only requires
micro self replicating extraction machines (plants), LunOx requires
either high temperature smelting/distilling or chemecal processes on
a large scale. True that Mars has a gravity well twice that of Luna
but less mass would be needed to extract.

>

> As for the mass of the inflatable clear domes, any which could
maintain
> adequate pressurization against a 1% atmosphere could do the same
against 0,
> I would think

True, but anything helps.

> An added benefit of an
> atmosphere, micro-meteor shield and a small bit of UV protection.
>
> The Martian atmosphere is a very poor UV shield. On both the moon
and Mars,
> precautions would have to be taken regarding exposure to UV for
both people
> and structures. As a meteor shield, it's certainly better than
nothing at
> all, but markedly inferior the Earth's atmosphere in this regard.

True again, but anything is helpful.

>

> Zubrin assumes nukes for Mars, too.

True that a fission reactor solves many problems. The problem being
getting the general public to allow it. Activists where throwing a
FIT when Cassini was launched and that was only an RTG. Plutonium
Oxide is much less dangerous than fissionalble material.
The point I'm trying to make is this. You could get a way with only
solar power on Mars. It would be costly mass wize, but you could do
it. It is unlikely that you could do so on Luna. You need too much
mass to store the energy for the night.

king_rodent (putting the eek in geek)