Thursday, September 24, 2009
F YEAH! After years and years of speculation, it has finally been unequivocally confirmed that there is water on the Moon (another link here). With water confirmed, now colonists in the area will be able to extract water, create breathable air and make their own rocket fuel without needing to bring it directly from Earth, so this is a really big story. It's the difference between trying to settle the peak of a mountain where one needs to bring each and every supply up from the ground and trying to settle the same peak but where there is a fountain of running water at the top.
The reason why this story is so big is that the debate up till now between the Moon vs. Mars has focused on the resources available on Mars vs. the paucity of resources on the Moon, but that was when we had assumed that the Moon was bone dry. Now, thanks to this, it has now been shown almost without a doubt that the place we first need to settle is the one three days' journey away, not six months (plus 2+ years of waiting for launch windows in order to get that opportunity to make the six-month journey).
As for the exact amount of water, the first article gives it: a two-litre bottle of lunar dirt would contain a medicine dropperful of water. Or, in order to get a drink of water it would take a baseball diamond's worth of dirt. This article from the New York Times gives the concentration as "one quart of water per cubic yard", which works out to 1238 ml per cubic metre. That's actually pretty good.
The article also notes that hydroxyl (HO) is also present, which is also useful.
The most interesting part of the article is that this trace amount of water had already been discovered in samples taken back from the Moon from the Apollo program, but it was assumed that it was simple contamination from the Earth's atmosphere and not native to the soil itself. Add to that the fact that they used data from Cassini's flyby (note: a very good example here of why successive flybys of even bodies we know very well is important) and this evidence has been around for quite a while, just not unequivocal until now.
One idea proposed for the source of this water has been comets, but since this water is present all over the surface that isn't as persuasive an idea as the theory that it comes from the solar wind, which hits the lunar surface, frees oxygen atoms in the minerals and allows them to recombine with protons and electrons, forming water.
Next up: LCROSS is due to impact the Moon's surface in two weeks. With this announcement LCROSS's mission just got that much more exciting. NASA will be holding a press conference today (Thursday) as well on the presence of water on the Moon, and looks like it's time for the rest of us to spread the news far and wide. This is exciting stuff.
Edit: this Australian news site has an article on the same subject, but something's wrong with the Moon in that picture, don't you think?
Unusually smooth. That's because it's Enceladus, one of Saturn's moons.
Edit 2: What the...another picture of Enceladus, this time from Cyberpresse.ca (La Presse). How many of these are there?