Moon Miners' Manifesto

#104 April 1997

Editorial

IN FOCUS: ICE on the Moon - Strategic Reserve, Strategic Choices

Distinctions have to be made: life support is impossible without water for food production and vegetation-based biospheres, drinking and hygiene. This use is largely recyclable, waste water filtered or treated to the point it can be used for plants; the plants transpiring humidity into the air; dehumidi-fiers drawing absolutely pure and potable drinking water out of that air to restart the cycle. Water can also be recycled in most industrial uses, even though, on Earth, it all too frequently is not.

Disassociated by electrolysis or solar power into oxygen and hydrogen for rocket fuel, however, it is used once, and forever lost. Fortunately, there are substitutes: anhydrous fuel combinations like liquid oxygen and powdered metal fuels (iron, aluminum, magnesium, calcium are all theoretical possi-bilities, with powdered iron by far the easiest to produce in an upstart outpost operation.); and hydrogen extenders: for example silicon, in the methane analog liquid "silane", SiH4.

So the question arises, if these ice deposits are rather skimpy, should they not be reserved for uses for which there are no substitutes? The rocket jocks (spade-calling time), many of whom (if the shoe fits ...) give no more than lip service to eventual resource development and the establishment of real settlements to support them (not confident that the economic rationale exists to make it happen) tend to be protective of the extravagant one-time use for rocket fuel to support admittedly more exciting and more near term space exploration type activities. They argue that the hydrogen, even if all used up in this fling, can be replaced with volatiles harvested from comets, as if, even though true, this were easy and cheap to do. "Hydrogen is the most powerful fuel" - true on paper, not necessarily in practice, as it is the least dense of all fuels, needing very large, proportionately heavy tanks, out of which it loves to leak (why shuttle external tanks are not fueled until just prior to departure time). We do need all that lift to boost heavy payloads out of Earth's deep gravity well. We may need it to boost payloads out of Earth orbit, even from the vicinity of the Moon, destined for the outer solar system. We certainly do not need that kind of oomph to lift payloads off the Moon, bound for Earth, low Earth orbit or geosynch-ronous orbit or for the L4 or L5 lunar co-orbital Lagrangian fields. these various points made, tempering reason is needed in several doses:

• at this time, we have NO idea just how extensive in area or in total cubic meters or kilometers the lunar polar permashade ice deposits are.

• we don't know how easy/difficult mining it will be.

• by the same token, we have also yet to demonstrate the economical production of silane on the Moon to use as a hydrogen extender, and liquid oxygen/ powdered metal fuel combinations have flown only on paper. There is one HELL of a lot of engineering to do. No one is doing it, because no one is willing to commit to the future - certainly not Congress nor its NASA tail (NASA has certainly wanted to do such research, but when Congress says no, NASA has never had the gumption to insist).

• that lunar resources are sufficiently valuable to fully and even profitably support lunar settle-ments and biospheres is a faith fanatically held by some (including myself) and doubted by others.

This said, we reject the claim that we have "no right to decide what future lunar settlers will want us to have done" with this unique resource in this, their prehistory. "They might" want us to blow it all on exploring the solar system, willing to go fetch ice from occasionally passing comets and asteroids when they need a drink, or a bath, or their plants are drying up. Without intending to introduce the same polarizing emotion that attends the abortion debate, we must protest, that if we don't speak for the unborn - in this case the lunar settlements - who will?

Our recommendation is this. We are not yet in a position to use the lunar ice in any way. So:

• now is the time to gather more information, and not get prematurely polarized over the issue. See the essay "Ice Man I, II, II" below. In the article, the "how to fund" question is addressed.

• Let's take silane and powdered metal rocket technology out of the orphanage and find out just what is involved in engineering real and reliable rockets using such fuels. We cannot demand their use instead of pure hydrogen if they exist only on paper. How do we fund such research? One way is the spin-up route whereby we brainstorm a terres-trial application promising near-term profits and then go ahead and develop the technology with that incentive - with or without a Congressional assist.

• When the probes and engineers have done all their homework then we can return to the debate. How you think it will all turn out depends upon your temperament - mine lies with the settlers and their biospheres. But until all the homework is done, I'll respect your beg-to-differs.

Teaser

Clones and the Space Frontier

Contents of this issue of Moon Miners' Manifesto