Lunar iron is the key to permanent, small scale settlements. At least that’s my hypothesis. Now I’ve got to prove it. The first step is to determine all the relevant properties of the iron we’re likely to find on the Lunar surface.
All of the data regarding Lunar iron has come from either indirect sensor measurements or directly from physical samples. While the remote data is incredibly useful, it has three flaws. First, it only tells us what’s on the surface. Clementine and Lunar Reconnaissance Orbiter could only measure the top micron of the surface (A Global Lunar Landing Site Study to Provide the Scientific Context for Exploration of the Moon, 418). There could be a layer of pure iron 1cm below the surface and we wouldn’t know it (how awesome would that be!). Second, the data doesn’t tell us about the physical state of the iron (size and composition) on the surface. Third, the spatial resolution of the sensing instrument will limit the usefulness of the data. For example, Lunar Prospector iron (FeO) measurements have a 0.5 degree-per-pixel resolution, which means each pixel is 15km x 15 km (A Global Lunar Landing Site Study to Provide the Scientific Context for Exploration of the Moon, 418). The value associated with a particular pixel is the average of the surface values for every point in the pixel (A Global Lunar Landing Site Study to Provide the Scientific Context for Exploration of the Moon, 418). This is a great start but we’re probably missing a lot of interesting stuff that’s just too small to pick out at that resolution. I’ll include as much relevant data collected from remote sensors as possible for completeness. But I anticipate that the bulk of the useful data will come from physical samples brought back by the Apollo missions.
Sure, the Soviets brought back 300 grams of samples from the Luna 16, Luna 20, and Luna 24 landing sites. But Apollo returned 382 KILOGRAMS of rocks, dust, and core samples from 6 sites. Over 2200 individual samples overall. Fortunately, NASA has the data from the Soviet samples so I don’t have to hunt for it (or learn Russian!). It’s important to note that the returned samples don’t represent everything on Luna. There is a lot more left to discover.
One problem with relying on physical samples is that rocks can travel far distances on Luna. A high energy impact can send debris flying all over the place. A particular sample might not be representative of its current location. Not much anyone can do about this but it’s something to remember.
Hopefully we’ll get some new samples real soon!
A Global Lunar Landing Site Study to Provide the Scientific Context for Exploration of the Moon