solar power sats

--- In spacesettlers@yahoogroups.com, "Dan Wylie-Sears"

> How much mass do you have to launch from earth for
> the parts of the moon base that vary from one scenario to another,
> as compared to the catcher?

If you want to build your base on the Lunar poles you need at least 2
more burns to get into a polar orbit and this simply increases the
delta-v thresholds that must be passed. All of the mass of the base is
harder to land at the poles rather than the equator.

Secondly, when you're launching from the poles, via mass driver, up to
orbit, you can't hit L2, so the catcher has to follow some orbit. Low
Lunar Orbit is unstable, so where will these catchers orbit. Also,
when they are stationed at L2 they are forever sliding down a gravity
slope and the incoming momentum of the material launched from the mass
driver keep them on the gravity crest. If you've ever surfed then
you'll immediately recognize the dynamic. This dynamic isn't present
in some lunar orbit and the momentum of the arriving payloads will
change the orbital dynamics of the mass catchers, and without
corrective burns on the catcher the orbital destabilization will be
cumulative.

> Until I see answers to those, my guess is still that it's better to
> site your moon base where you can get the stuff you need most at
> first and make a bunch of allowances for that, than to site it where
> you can't get what you need most first. And I think what you need
> most first is reaction mass so that you don't have to pay the rocket
> equation the whole way. For anything that includes a catcher and a
> mass-driver, the reaction mass can be just plain rock. For anything
> else, it just about has to be hydrogen and oxygen. Yes, you can
> lift the hydrogen from earth and only rendez-vous with the the
> oxygen, but that means having to rendez-vous with the trajectory it
> was on from the moon. If you rendez-vous with both components of
> your fuel, you can have it do its part to make the rendez-vous.

One has to optimize the availability of the resource and the amounts
of materials that will be required. The only appeal of the lunar pole
is that there is some hydrogen there. Are the problems of launching
all of the mass of the remaining materials worth the hassle so as to
have easier access to a source of hydrogen?

I don't think so, and I've laid out my thinking in this post:

Long time listmembers will have already read the Bootstrapping in 60
Easy Steps post.

TangoMan