New here, asteroids prefered

bhn1700 wrote:

> Actually you're making errors in fact and logic, first commercial
> companies are paying for research on ISS in zero g (an application)

Which companies? How much? I wasn't aware of this.

> second space tourism includes not just great views and rocket trips but
> the zero g environment

True, but that's an extremely limited (though admittedly nonzero) market
at this point. And at least two of the handful of space tourists has
openly expressed a desire to go to the Moon:

http://www.popularmechanics.com/science/space/4266744

So I don't think you can make a strong case that orbital tourism is
preferable to lunar tourism, except that it's available and the latter
is not (yet).

> third this site lists 'spinoff' commercial
> benefit from the space program some coming directly from zero g work.
> http://www.thespaceplace.com/nasa/spinoffs.html

Yes, but have you read this list? This is the old and tired argument
that the investment in NASA (note: not in microgravity research per se,
but NASA in general) has resulted in innovations that wouldn't have been
made otherwise. But most of those innovations would have been produced
far more cheaply if they had been invested in directly.

I'm not arguing that there aren't some valuable spin-offs, but this is a
weak argument that NASA supporters often try to take way too far.

> On your second point you are the actually confusing cause and effect, we
> didn't pick research on ISS as a random location and then can claim
> what's found is linked to zero g, we purposely did research in zero g
> and so the applications come from the zero g research.

Your logic is dumbfounding. Let's review:

1. It was claimed that "To date in our extraterrestrial experience it's
the ABSENCE of gravity that has produced commercial applications."
2. I pointed out that the only extraterrestrial commercial applications
possible would be in the absence of gravity, since we don't have any
extraterrestrial operations except in orbit.
3. You counter that... well, I can't make heads or tails of your
counter. Yes, we're doing our space research on ISS, because that's the
only place we have. Claim 1 is still a pointless tautology.

> > [A bunch of hypothetical stuff that has never been proven and, in my
> > opinion, have a low probability rather than a high one.]
>
> See above link, and maybe a basis, reasoning and/or evidence for your
> claims of hypothetical, never proven, and low probability statements.

No, if you have any one of those things that you think is NOT
hypothetical and unproven, let's see the actual non-hypothetical
products that prove them. I'm asserting that there aren't any; there's
nothing I can show to prove that, but you can easily prove the reverse.

As for the probability, that's a matter of opinion I guess, but the
original poster was claiming "results with a high probability of
commercial applications." I'm choosing to disagree.

> > > what do you have to sell, or what potential can
> > > you offer to prospective manufacturers to set up shop there?
> >
> > Are you kidding? Metals, volatiles (including H2 and O2), bulk mass for
> > radiation shielding... let's not kid ourselves, space is mostly vast
> > stretches of emptiness, full of plenty of solar energy (at least in the
> > inner solar system) but not much else. Sources of materials are
> > valuable, and hauling them up from Earth is dangerously close to
> > impractical.
>
> Again everything you just listed is in the asteroids except with even
> more diversity of material and even more solar energy (since a 28 day
> cycle leaves a lot of dark time on the moon).

Of course. I have never claimed that asteroids aren't great sources of
material. I only claim that they're not immediately USEFUL sources of
material because of the logistical difficulties their use presents.

That's the great thing about the Moon, though; everything you can find
in NEOs, you can probably find on the Moon, and it's right there 400
thousand km away all the time. See, for example:

http://www.thespacereview.com/article/205/1

So we agree that we should use NEO materials, which which have undergone
the major delta-V required to bring them into safe, stable Earth orbit.
But you're arguing that we should go out and effect that orbital
change, and I'm merely pointing out that the Moon has does this for us
already.

> Also hauling materials
> from the moon, in reference to the previous delta V discussion, is far
> more expensive then the moon.

What?

> > > Then
> > > there's the factor of getting those products to their markets: 1/6 g,
> > > while miniscule in comparison to Earths, will still require
> significant
> > > use of fuel (or a significant outlay for a linear accelerator,
> skyhook,
> > > etc.)- much more of an expense than would be incurred by shipping
> from a
> > > zero g habitat.
> >
> > Barring such a magic wand, you have to compare the expense and
> > difficulty of building the mass launcher on the Moon, to building a
> > space habitat. The latter is probably about 100 times harder.
>
> Um, who needs a habitat to process a 10 meter asteroid?

I was replying to the claim above comparing use of a linear accelerator
to "shipping from a zero g habitat."

> But the moon is further out without any current infrastructure, unlike
> ISS, and you'd have to build the mass launcher. A very energetically
> costly facility that is not needed for the ISS counter part, most mass
> launchers call for huge energy requirements in order to accelerate mass
> to escape velocity.

True, but there's plenty of energy available. Reaction mass tends to be
a bigger problem than energy. To get materials from an asteroid (or an
entire asteroid) into a useful orbit, you have to expend energy AND
reaction mass.

> Probably alot of water, not alot of other volatiles though N,C,S,P and
> even limited current understanding is the asteroids have alot more of
> everything.

Maybe. I think the main thing we've learned in the past couple of years
is that many of our assumptions about lunar resources are wrong. At
this point it seems premature to assert that the Moon doesn't have any
of those other volatiles.

> And again in a much higher gravity well and further away.

Higher gravity well, yes. Further away, no. That's the big problem
with asteroids -- they rarely come even as close as the Moon, and when
they do, they don't stick around long. Any excursion to use of them is
by necessity a very long-term project involving months or years away
from cislunar space. It's mighty cold and lonely out there, at least
for the near future.

Best,
- Joe

P.S. Thanks to all for the lively and thoughtful discussion.