Arecibo can't find any ice on the moon.

I think we should be planning asteroid/comet missions, anyway. The private sector is more likely to do that, since they'll be more focused on the practical use of resources than science and symbolism.

Rand, water is 1/9th hydrogen and 8/9ths oxygen by mass.

No lunar water ice? A disappointment but not a show stopper. Oxygen is everywhere on the moon.

I didn't say it was a show stopper. But I still think we need to be looking at NEOs.

I agree. Capitalizing on asteroidal commodities seems like a much more attractive option to me.

Josh, can you amplify this?

I agree. Capitalizing on asteroidal commodities seems like a much more attractive option to me.

If Dennis Wingo is wrong and there are no platinum bearing asteroid fragments on the luanr surface, then I will grant the point. If there are, processing those in 1/6th gravity will be far easier than in zero-gee out at some NEO.

As for volatiles, if someone can harvest O2 on the moon and ship H2 from Earth, it seems to me that water made by burning Terran H2 with lunar LOX will be far cheaper to acquire than NEO H2O.

At least at first.

That said, I fully support going to the NEOs.

Sure, terran H2 water will be a lot cheaper on the moon, but how does it compare to NEO water once it's transferred to L1?

This might be just me, but I can't imagine that people would want to live on a rock with a huge gravity well and no atmosphere any more than they'd want to live on a Cambodian minefield.

The way I read the various aricles that refer to the Nature article, it seems that the high circular polarization ratios that were once assumed to be indicative of Hydrogen (and thus, water ice) also appear in high resolution radar images of areas that could not have water ice on the surface. This implies either that the water ice is mixed in with the regolith (as asserted by Mark Whittington) or that the high CPR does not indicate water ice after all (as I asserted in a comment on Bad Astronomy when Phil Plait brought this up a few days back). At any rate, the angle of incidence of radio waves from Arecibo is (at best) pretty much the same as the angle of incidence of light from the sun, so that radar could never look into the bottom of a crater at the lunar South pole anyhow. These Cornell researchers have set up and knocked down a strawman.

When the analysis was done on how much it would cost to build an O'neill habitat, the cost and payback period per person was so high that the construction of such habitats was considered unfeasible by profit-seeking private groups.

This has lead Freeman Dyson (who is now the president of the Space Studies Institute) to promote and do research aimed at the settlement of asteriods by "small" groups of individuals.

There are the NEOs, the main belt, and in the more distant future the Kuiper belt. If human settlement is to be focused on large bodies, we're pretty much limited to Luna and Mars.

I thought it was always understood since the 1970's that the "small bodies" (asteriods, comets, KBOs) was where the action would be.

If we should be prospecting for asteroid ice, might I suggest Deimos? The payoff would be much easier transportation to and from Mars.

Deimos? Absolutely, IMHO. The delta V from Deimos to EML-1 is actually quite low, relatively speaking and that station can serve multiple purposes including helping to open Mars as well as ship volatiles to cis-lunar space.

= = =

As for EML-1 water supplies, you can ship LOX from Luna to EML-1 and H2 (or other better stored fuel) from Earth to EML-1. Shipping H2 to Luna so you could ship the water to elsewhere would be silly.

An added benefit of shipping fuel and LOX separately is that if the fuel and O2 would arrive already divided no energy input is needed to crack them apart. Then, if combusted to make water for long term storage (through a fuel cell, for example?) the station benefits both from the water and electricity generated by the fuel cell.

Ed,
What Campbell et al have mostly knocked down is the idea that the Clementine bistatic results indicated water ice, given that they were constrained by the precisely the same geometry. Hardly a strawman. There is now no strong compositional (as opposed to elemental) evidence for discrete water ice bodies on the moon.

Evidence for hydrogen has not been knocked down, though ?
The question is, in what form does the hydrogen exist ? And no amount of radar observations will tell us that, you need to get there and drill.
CMU IceBreaker should have sent there years ago, when it was first conceived.

It still can, as soon as NASA stops raping the science budget to duplicate the capabilities of commercial boosters.