I wanted to revisit David Jensen's 65-page opus on asteroid colonisation. I was thinking Bennu; Jensen's mostly talking 163693 Atira. A Pawnee name sometimes pointed, I think unnecessarily, "Atíra".
Apparently - per Jensen - Ateeeera offers more resources for the delta-V expended to get there. It's one of the larger ones; and it's "S", for "Stoney". Its 1.87 g/cm3 density although higher than the 1.19 of rubbley Bennu is still lower than, say, Eros'. Just from volume considerations Atira's more likely to own appreciable hydrous stuff under the regolith. Enough to support a colony, if additional water gets imported and adequately-recycled.
I do however have a few animadversions, which I'll proffer here . . .
That 16.7 delta-V, from Earth, isn't a joke; compare Ryugu 6.76. I don't know that Jensen has porkchopped how to get here but its semimajor is 0.7411 AU just outside Venus' 0.723332 AU. It's eccentric, out to 0.9798 AU; but that's still going far outside Earth's reach given 25.618° inclination (Hill Spheres, man; they're a pain). And it does get close to the Sun, such that I am unclear it has (anymore) such volatiles sufficient to Colony-Jensen requirements.
At that inclination it is difficult to imagine what longterm use Atira would be for the rest of our solarsystem. A difficulty which I'll get to, "tomorrow" evening. UPDATE 7/12 Then there's Jensen's whole "RoI" thing. UPDATE 8/23: Ol' Boom-Boom? ...anyone?
BACKDATE 7/10
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