SSI Activity (and its rebirth?)

>
> That would be the ticket if it could be done. But I'm not optimistic
> about the prospects for that in any near-term future. In any era in
> which I might live to see, I'd be mightily impressed by a replicator the
> size of a small apartment building.
>
> I expect (and I think SSI expected as well) that the first orbital ore
> refinery, metal-working shop, and manufacturing facility will be tiny in
> comparison to their Earthly counterparts, but still quite a bit larger
> than what you're visualizing. Still, I'd expect them to replicate a
> number of times before achieving the industrial throughput desired, and
> so would still tend to view them as industrial "seeds".
>

I have to say, I'm with Mike on this one. Many nanotech researchers don't think nano-scale
assemblers will ever happen; some that are, are looking at biological processes for
inspriation. The problem with the latter is that it's entirely possibly the replication
processes will require things that the Moon isn't known for, to be able to replicate, such as
an organic soup at ready disposal.

So, if you want to create a self-replicating habitat, you probably don't want to start on the
Moon. This isn't a concept killer, but it complicates things.

What attracts me to O'Neill's vision is that it's based on present-day technology. (A caveat:
while my copy of The High Frontier is on order, I haven't read it, but I'm working here with
the ideas I've read on the Web). No major advancements have to be made; in a sense, it's
just looking at building construction when you subtract gravity from the force equations.

I think what could be done 'cheaply', however, is setting up an automated mining system,
which could do much of the initial activity O'Neill had in mind without involving people.
Sort of an ant colony that packages together bundles of minerals to be sent to an L5 point
via a mass driver, etc.

I like the idea of such robots being able to reproduce somehow - possibly by sending just
the manufacturing plant and a few starter robots to tap into lunar resources to start the
process of generating more of them - but the problem here is again the available
resources on the Moon. One of the most important resources for manufacturing is water,
especially when doing anything high-tech, like making computer chips. Literally tonnes of
water go into making a single computer, for example. While this could no doubt be done
with less water - the main reason it's not is economic - it's still a requirement. Assuming
that there's no water on the Moon (the jury's still out on the presence of water at the
poles, so I'd say it's important to plan for the case where there's none), then you'd have to
ship lots of water to the Moon with your assembly plant, and said plant would have to be
able to manufacture robots, purify water and recycle it while losing only a negligable
amount of the stuff.

Alternatively, it could manufacture some components, have the rest periodically shipped
to it, and make more robots when the resources become available.

I don't think the idea of just growing a colony out of a rock is realistic, at least in the near
term. Getting robotic mining working does seem doable to me - it's more along the lines
of Rodney Brooks' research (http://www.ai.mit.edu/people/brooks/index.shtml) than
anything absolutely bleeding-edge. Getting it working is doable in the short term, if
challenging. Getting it reproducing is still science fiction. That doesn't mean it's
impossible, but there's a lot more work that has to be done first if it is.

Vince