Some data from our own Moon is rolling in. A zircon from Apollo 17 is reading a 4.46 Gy age. This restores earlier estimates, back from the 4.425 Gya which Vox Day told me about. I mean, unless the zircon hails from old-Earth or Theia which no-one seems to accept.
In future we might not need the moon proper for our sample-return needs. The 100m-ish achondrite (not "tektite", boomers) (469219) 2016 HO3 was already known to be lunar, not a S-type. It lately turns out this one got coughed off the Lunar surface some millions of years ago and will stay in its Earthlike orbit for millions more, long after the squatters demanding we call it "Kamoʻoalewa" become a footnote. UPDATE 4/26/24: Bruno?
I don't find a settlement of colonists upon this dried-out moonchunk, worth the bother. Also I don't think we've a handle on whence, on the Moon, it came. I think, though, that it would make for a fine locus for its own zircons; also, maybe we should get that handle on its origin. And 'tis always cheaper to dock with a floater, than to land and take off onto/from 1.625 m/s2.
COUNTERFACTUAL 5/6/24: Suppose Theia's materiel was available for agglomeration into Earth before 4.46 Gy. Softer and more-scattered planetesimals, merging with a softer protoEarth. We'd not have our Moon; Earth would just be... bigger. Early-enough and it retains more volatiles. And does the dynamo ever abruptly stop? I'm thinking: waterworld.
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