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In lugnet.off-topic.geek, Dave Schuler wrote:
> By now, everyone knows about Dubya's Brave New Vision of America's future in
> space, specifically regarding the Moon and Mars. One of Dubya's selling points
> for a permanent Moon base (perhaps modular, in 48x48 squares) is that it will
> make it easier to launch spacecraft to Mars "and beyond." But will it?
>
> I believe that one of the arguments is that it takes X amount of fuel to go from
> Earth to Mars, but only Y amount of fuel to go from Earth to the Moon and only Z
> amount (i.e., less than X) to go from the Moon to Mars. Dubya seems to be
> suggesting that, in lauching from the Moon to Mars will use only Z amount of
> fuel and will therefore be more efficient than an Earth-based launch.
>
> Here's my quandary: Don't we still need to transport the fuel from Earth to the
> Moon, and doesn't it take fuel to get there? If so, is this really more
> efficient? If so, it is sufficiently more efficient to justify a multi-billion
> dollar construction project on the Moon?
Boost the fuel (and oxidizer) from earth?
Fuel maybe, oxidizer no.
The moon has among its most common elements: oxygen, silicon and aluminum
Solar cells can be made from silicon and aluminum + trace elements. Just add
energy. (and technology that you brought with you)
Rocket fuel can be made from aluminum dust. Just add energy (and ditto)
Rocket oxidizer can be made from oxygen. Just add energy (and ditto)
The moon gets 2 weeks solid non stop sunshine a month, with no clouds to get in
the way. That's a lot of energy.
Proposals I have seen for using a moonbase as a true BASE involve setting up
automated manufacturing operations on the moon... send a small plant up that can
make solar cells, use it to bootstrap up to a larger plant that makes solar
cells, use that to bootstrap up to a plant that makes rocket oxidizer and fuel.
If aluminum dust fueled engines are too far out, you still can get a lot of
savings from making the oxidizer locally, even if you brought the fuel with you.
OR... build an electric catapult to get things into low lunar orbit, then switch
to ion drive, which is electric (and thus non chemical and thus much higher
specific impulse). Aluminum ions or oxygen ions would work fine.
NOW... is that the way NASA is going to do it? Doubtful. This is a boondoggle
pure and simple, some sort of focus group driven election year pap from which
nothing will come.
But if you really want a permanent manned presence on the moon with industrial
capability and lift capability it's (in my opinion) VERY doable for the numbers
being thrown around (like 12 billion USD over the program life).
Just give the money to Burt Rutan, and be willing to accept some deaths during
the process. (on the order of how we used to be willing to accept a death or
two, with handsome payments to widows, during the construction of large bridges)
It is my sincere belief that he's going to make a profit winning the X prize.
And not kill anybody doing it either.
Don't confuse accepting some death with planning for it or planning to do things
slipshod. It just means that you don't necessarily defend against every last
contingency. Bridges used to be built without safety nets.
XFUT .debate since the notion of accepting death in large projects is a bit
controversial, so is the statement that Bush emits election year pap on a
regular basis (ok, maybe that one isn't??)
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Message has 1 Reply:
 | | Re: We're here to go
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| (...) Okay, that's pretty cool (but you lose points for using "bootstrap"). I was only thinking of vehicles launched from Earth and using the Moon as a waystation, rather than craft built in orbit or on the Moon. But wouldn't it be monstrously (...) (20 years ago, 16-Jan-04, to lugnet.off-topic.geek)
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Message is in Reply To:
| | We're here to go
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| By now, everyone knows about Dubya's Brave New Vision of America's future in space, specifically regarding the Moon and Mars. One of Dubya's selling points for a permanent Moon base (perhaps modular, in 48x48 squares) is that it will make it easier (...) (20 years ago, 16-Jan-04, to lugnet.off-topic.geek)
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