models support NEO material deposits on the Moon

On 5/30/13 1:11 PM, brooksn wrote:

> But if we capture small asteroids already on a near miss with Earth and
> bring them into lunar orbit all the cons you listed go away.

That's true. But we can only do that with very small asteroids.

> And if prove that one can be captured and mined, then we can capture
> 100 the same way.

True, but it's likely to cost 100 times as much (and take 100 times as
long) as one. Maybe not quite; we'd certainly learn to do it better
with time, and get some savings from more frequent launches. But I
don't see the same economies of scale you'd get from planting mining and
launching equipment in a fixed place on the Moon.

> I think Bigelow is interested in space generally and his habitats
> everywhere specifically. I don't see the advantage in the moon over
> captured lunar orbiting asteroids. Given everything it takes to do both
> it seems the lunar asteroids should beat the moon every time.

If we imagine a ready supply of already-captured asteroids, yes. But
lacking such lunar orbiting asteroids, a big deposit on the Moon easily
beats a tiny rock millions of miles away.

Now, if we could show that there was already PGM-rich material lounging
around at L2 or some such, that might be another story. That could well
be worth exploiting. But I'm not aware of any indications that
significant amounts of material exist there -- such orbits are unstable
in the long run, I believe. (Somebody please correct me if I'm mistaken.)

Things on the surface of the Moon, on the other hand, are extremely
stable. The Moon's been collecting material for us, albeit at a slow
rate, for 4 billion years... I think it's about time to cash in!

Look at it this way: we both agree that asteroids are a good source of
material. We also both agree that having them in the vicinity of the
Moon is quite convenient. We differ only on one minor point: you want
to go take small asteroids that aren't already in cislunar space, and
wrestle them into a convenient orbit; I want to use much larger
asteroids whose orbits have already been altered (quite abruptly) for
our convenience.

Best,
- Joe