Questions about "The High Frontier"

On Fri, 19 Oct 2007 13:10:07 -0500, "Mike Combs"
wrote:

"John Schilling" wrote in message
.. .

But it's probably going to be a *lot* less expensive if you allow for
the inhabitants to build, provision, and resupply their habitat using
local resources.

And there's every reason in the world to expect an asteroidal settlement to
be doing this.

Except for the critical shortage of local resources that aren't steel or
coal or glass.


And Mars has a much broader range of useful resources
than any NEO. Than all NEOs combined, probably.

I'm not sure why you would say this. What resources would be available on
the surface of Mars that you couldn't find in a well-selected CC-type
asteroid?

"CC" meaning "Carbonaceous Chondrite" generally?

OK, let's see: How about useful concentrations of Helium, Lithium,
Beryllium, Boron, Nitrogen, Fluorine, Neon, Sodium, Aluminum, Chlorine,
Argon, Potassium, Titanium, Chromium, Manganese, Copper, Zinc, Arsenic,
Bromine, Krypton, Strontium, Zirconium, Niobium, Molybdenum, Silver, Tin,
Antimony, Iodine, Xenon, Barium, Hafnium, Tantalum, Tungsten, Gold,
Mercury, Lead, Bismuth, Thorium, and Uranium.

Mars definitely has some of those in abundance , and almost certainly has
useful ores of the rest on account of having experienced the same geologic
processes that produced such ores on Earth.

Carbonaceous chondrites, based on the meteoric evidence, do not. They're
just raw primordial dust, slightly baked.

Asteroids, are where you get steel and coal and glass, and maybe magnesium
and platinum for the export markets, and that's really about it. Worth
mining, yes. But the bit where aseteroids are Cornucopias of Abundant
Everything, is one of the staples of science fiction that isn't terribly
well grounded in actual science.


Mars also has gravity, which is quite useful if you want your inhabitants
to remain, like, alive and stuff. Providing gravity on or near an NEO is
rather hard, especially at small scales.

I wouldn't so much say "hard" as "requiring a certain minimal scale". If
one has two counter-rotating structures of equal mass, nothing is required
to spin them up and keep them spinning other than an electric motor between
them.

Making them useful requires more than just keeping them spinning, as you
ought to know by now. And the minimal scale issue is critical, because
the first outposts are going to be small and the first big colonies are
going to be where the outposts already are.


Right, so, settling Greenland is likely to be less expensive for
hypothetical European explorers than settling North America or the
Carribean?

I think you would find the magnitude of the relative energy differences to
be very large.

You'd have done better to put an actual number on that.

But, better still to explain why you think the relative energy differences
are so important in the first place. Yes, they are the easiest thing for
you to calculate. If you start with the premise that all the important
questions can be answered in an afternoon's idle thought, that's what you
are left with.

But the premise is false, because real-world economics are a whole lot
more complicated than that. Energy is rarely the dominant consideration.


--
*John Schilling * "Anything worth doing, *
*Member:AIAA,NRA,ACLU,SAS,LP * is worth doing for money" *
*Chief Scientist & General Partner * -13th Rule of Acquisition *
*White Elephant Research, LLC * "There is no substitute *
* for success" *
*661-718-0955 or 661-275-6795 * -58th Rule of Acquisition *

Troy wrote:
An L5 asteroid can provide a number of services:

I don't see how being in L5 is much of an advantage for most of these.

1G R&R for lunar base
personnel (you can get away with at least 4RPM and 100m diameter),

This can be built on the Lunar surface, where it'll be much more easily
accessible.

light elements production and reaction mass supply,

Seems like a lot of extra expense moving an entire asteroid to L5 before
mining volatiles out of it when one could mine the volatiles on-site and
ship just those back.

beam solar power
to moon bases,

A habitable space station isn't needed for this.

serve as a space hotel,

This one, sure.

mount deep-space telescopes,

You definitely don't want to mount telescopes on anything that has to
have humans living in it. A human habitat would be a source of vibration
and volatile contamination.

manufacture stuff on demand for other orbital operations,

Why not do most of that on the Moon and launch the finished components?

serve as a
skyhook or supply mass for skyhooks and do all the microgravity
research you can shake a stick at.

I can't recall any proposals for stringing skyhooks out to L5. L1 and L2
are the usual destinations.

Plus you have a "saving the Earth"
case for stick-in-the-muds.

By deliberately moving an asteroid _toward_ Earth? It probably wouldn't
be a serious risk if done in any halfway competent manner, but the
shrapnel from the heads of environmental activists exploding in apoplexy
at the thought could be quite hazardous.

And the habitat does not have to be stuck
to one asteroid; it can be a mobile "mining town."

I don't think having multiple asteroids in L5 would be a stable situation.

I agree with your points about the Moon being a more likely near-term
resource base than Mars, though. And mining near-Earth asteroids
in-place will be a good source of materials that the Moon lacks. I just
don't see the need to build a giant manufacturing settlement in a place
where there are no resources and then have to set up colonies elsewhere
to import the raw materials from anyway.

On Thu, 18 Oct 2007 22:15:05 -0700, Troy wrote:

On Oct 19, 9:48 am, John Schilling wrote:
Right, so, settling Greenland is likely to be less expensive for
hypothetical European explorers than settling North America or the
Carribean?

True, but look at Hong Kong. The Brits wanted it for its trade
potential; look what became of it.

Yes, but so what. Hong Kong is what it is because it's a nice
transport hub right next door to a billion hard-working people
who'd like to buy some nice stuff (or, barring that, some drugs).

There's about a thousand islands in the middle of the Pacific
Ocean that have natural harbors as good as Hong Kong. Look at
what became of *them*.

Some of them were settled. Damn few of them had anything
remotely resembling a city built on them. Rather more were
ultimately abandoned outright or left to subsistence-farming
(well, fishing) natives.


People go where the trade is happening, so cyclers habitats may
eventually become quite large.

When did we start talking about "cyclers habitats"? I thought
we were talking about asteroids.

And "where the trade is happening", is where there are bignum
people waiting to buy the stuff being traded. You might want
to think about what that implies, and try to avoid any catch-22s
where people go out to L5, Mars, the asteroids, or whatever, for
the purpose of being the market that will support the trade that
justifies their going out there in the first place.


Ultimately, an O'Neill scale hab will give you more of an Earthlike
environment than on Mars.

In addition, a passenger ship to L5 can be more like an airliner,
whilst to Mars you're looking at something like a small cruise ship
for the same numbers.

Actually, Earth-L5 wants to be a week-long trip, which is right
there in cruise-ship territory.

But when did we start talking about L5? I thought we were talking
about asteroids?


An L5 asteroid can provide a number of services:

Oh, we're talking about "L5 asteroids". And presumably some sort
of "cycler asteroids" as well.

These have several serious shortcomings as potential colony sites,
the most significant of which is that they do not exist.


1G R&R for lunar base personnel

Which brings us the question of what the lunar base is going to be
doing. The usual justification for large lunar bases is mining raw
materials for the folks at L5 to use, which gives you one more
catch-22.


light elements production and reaction mass supply,

From where, exactly? Are you still talking about L-5 here, or are
we back to the asteroids?


beam solar power to moon bases,

Have we moved yet again to L1 or L2? Because you might want to do
the math on power transmission from L5 to the Moon - it turns out
to be roughly as difficult as power transmission from the Earth
to the Moon, and we've got lots more cheap power (and cheap power
transmission hardware) here on Earth.


serve as a space hotel,

For what market?

If you're talking about rich tourists from Earth, I'm thinking they
will prefer Low Earth Orbit. Easier to get to, cheaper, safer, and
a much nicer view. There may be some novelty value to the Moon or
even Mars as tourist destinations, but L5 and/or the asteroids are
not likely to be competitive unless your hotel-builders can share
infrastructure with other, larger operations.


mount deep-space telescopes,

Those, unfortunately, really need to be in a place where nobody else
is doing much of anything.


manufacture stuff on demand for other orbital operations,

Possibly, but that can be done just about anywhere, so you'll need
to be more specific about why it should be done on an asteroid. Or
at L-5, and remind me again which you are talking about?


serve as a skyhook

What, did we now move to geostationary orbit? Because L-5 is a
completely unsuitable place to run a skyhook, asteroids are even
worse, and even an asteroid at L-5 wouldn't help.


and do all the microgravity research you can shake a stick at.

Except for the slight problem that once you've got all that other
stuff set up and running, you really only have milligravity, and
that's not particularly interesting to the researchers.

Microgravity research, like astronomy, is best done in isolation.
And it can usually be done quite nicely in LEO, so you'll need to
explain why people are going to be going much farther.


Plus you have a "saving the Earth" case for stick-in-the-muds.

You're going to have to explain that one, I'm afraid.


And the habitat does not have to be stuck to one asteroid; it
can be a mobile "mining town."

That's mighty inconvenient for a "center of trade". And I'm
pretty sure that everyyone who has invested in infrastructure for
an R&R base, solar power beaming station, space hotel, observatory,
factory, microgravity research station, or *skyhook*, is going to
just tell the wannabe asteroid miners, "How nice. Why don't you
go wherever you want and do that, and we'll stay here where all
our stuff is, and if you find anything nice, bring it back here?


All that, and it's 3 or 4 days away,

Wait, you're going to be moving it around from one asteroid to
the next, *and* keeping it three or four days away from Earth?


What, economically speaking, can you do on Mars?

Well, I can set up an R&R facility for asteroid-base personnel,
produce light, medium, and heavy elements and reaction mass and
food, set up a hotel or an observatory, manufacture stuff on
demand for other orbital operations, set up a skyhook, and I
might just be able to set up a "saving the Earth" case for the
stick-in-the-muds, whatever that means. Toss in Mars orbit
and we can do the microgravity research. Plus there's a couple
of captured asteroids close in in case I need them.

Sound familiar?

And the thing is, Mars is *one place*.

You've gone and thrown in every justfication you've ever heard
for any sort of deep-space operation, without regard for the fact
that they have mutually contradictory requirements and will
collectively require setting up shop in a dozen or more very
*different* places.

If Mars isn't the absolute best place for any of these things,
it's still good enough for a lot of them, and it's *one place*.

So, you're going to get outposts on the Moon and at L-1 and L-5
and in LEO and GEO and in a cycler orbit and on half a dozen
different asteroids, each with a small group of people doing
the one thing that place is best for.


Where's the actual city going to be? The place where people
are doing more than just one thing? Because, see, if you're
going to build a city, or even just a town, you have to pick
*a* place for it, and it has to be *a* place that's suitable
for *all* the things the townsfolk want to do.

I'm not actually sure what that place will or should be myself.
But I do know better than to throw Mars out of the running just
because I can think of half a dozen places that would be better
than Mars for *one* thing.


--
*John Schilling * "Anything worth doing, *
*Member:AIAA,NRA,ACLU,SAS,LP * is worth doing for money" *
*Chief Scientist & General Partner * -13th Rule of Acquisition *
*White Elephant Research, LLC * "There is no substitute *
* for success" *
*661-718-0955 or 661-275-6795 * -58th Rule of Acquisition *

John Schilling wrote:

If you start with the premise that all the important
questions can be answered in an afternoon's idle thought, that's what you
are left with.

The foundations of USENet tremble, and as for Slashdot...

On Oct 20, 11:08 am, Hop David wrote:

This is like saying if modest log cabins were good enough for the
pioneers then why should their descendants bother with high rise buildings.

Because building things in space (whatever those things may be)
doesn't automatically lead to either log cabins or high rises.
Someone mentioned oil rigs a few posts back; we may have 24-hour crews
on them, but the crews don't stay on the rig for their whole lives and
raise kids. There are no "oil rig cities", so far as I know.

"Damien Valentine" wrote in message
ups.com...

OK. Then why bother with the O'Neill Cylinder? Or, for that matter,
the Stanford Torus or the Bernal Sphere? If they all produce the same
product (whatever that product may be), and the Space Manufacturing
Facility is orders of magnitude cheaper, then there's no point in
building million-plus-ton behemoths in space.

Like I said, only one: To permanently colonize space.

On the other hand, one might note that with the SMF with the spartan living
conditions one sees quick turnover in skilled workers. People sign-on for 2
year tours (or whatever), fill up their bank accounts, and then come back to
Earth to spend their money, because what are they going to spend it on
living in an aluminum can in HEO? Then you might note that since you've got
mining facilities on the moon and/or a NEA, a means of transporting ore to
HEO, ore refineries and parts fabrication facilities in that same orbit,
most of what you need to build a Bernal Sphere or Stanford Torus is already
in place (and perhaps already paid for by SPS profits). So it might be
worth a bit of investment for your workers to be able to live under natural
sunlight surrounded by greenery, and able to do ordinary things like fish in
a pond or walk in a park. Perhaps highly-trained and skilled workers might
be more apt to spend their entire careers with you if they can look at their
apartment or house in Bernal Alpha as "home" rather than some place on
Earth. Families might be more apt to form in such a place than in a place
which more resembled an off-shore oil rig.

Then the way to look at the O'Neill Cylinder is that it won't even be the
present civilization which will build it. It will get built by a future
space-based civilization, which will get its start in far more modest
habitats.

--


Regards,
Mike Combs
----------------------------------------------------------------------
By all that you hold dear on this good Earth
I bid you stand, Men of the West!
Aragorn

"John Schilling" wrote in message
...

OK, let's see: How about useful concentrations of Helium, Lithium,
Beryllium, Boron, Nitrogen, Fluorine, Neon, Sodium, Aluminum, Chlorine,
Argon, Potassium, Titanium, Chromium, Manganese, Copper, Zinc, Arsenic,
Bromine, Krypton, Strontium, Zirconium, Niobium, Molybdenum, Silver, Tin,
Antimony, Iodine, Xenon, Barium, Hafnium, Tantalum, Tungsten, Gold,
Mercury, Lead, Bismuth, Thorium, and Uranium.

You may have a point here, although I would venture to say that we use minor
quantities of these materials in comparison to steel, glass, and concrete.
Perhaps asteroidal settlements will buy aluminum and titanium from lunar
colonies, who in turn will be interested in buying hydrogen, carbon, and
nitrogen from asteroid settlements.

Making them useful requires more than just keeping them spinning, as you
ought to know by now.

Yes, but the question we were dealing with was what is the extra expense of
having to provide your own gravity. So it's a valid point.

But the premise is false, because real-world economics are a whole lot
more complicated than that. Energy is rarely the dominant consideration.

It's currently the dominant consideration in space, and is likely to remain
so for the foreseeable future.

--


Regards,
Mike Combs
----------------------------------------------------------------------
By all that you hold dear on this good Earth
I bid you stand, Men of the West!
Aragorn

"Bryan Derksen" wrote in message
news:E8SSi.105062$th2.51759@pd7urf3no...

Seems like a lot of extra expense moving an entire asteroid to L5 before
mining volatiles out of it when one could mine the volatiles on-site and
ship just those back.

Then there's one idea that I like: If you're using a mass-driver as your
reaction engine, the beauty of it is that you can use literally anything for
reaction mass. So maybe you start materials processing on the way home, and
use the dross for reaction mass. Then by the time you get home, what's left
is the high-dollar materials.

I don't think having multiple asteroids in L5 would be a stable situation.

It would depend on how massive they were. If they were only the size of an
apartment building, I don't see any reason why you couldn't have a chain of
them following a kidney-bean-shaped orbit around either L4 or L5.

I agree with your points about the Moon being a more likely near-term
resource base than Mars, though. And mining near-Earth asteroids
in-place will be a good source of materials that the Moon lacks. I just
don't see the need to build a giant manufacturing settlement in a place
where there are no resources and then have to set up colonies elsewhere
to import the raw materials from anyway.

Gerard O'Neill listed a number of reasons why a habitat in a free orbit
might have advantages over one placed on a celestial body:
http://members.aol.com/oscarcombs/sp...htm#advantages

Some of these advantages might pay for moving a few megatons of ore around.

--


Regards,
Mike Combs
----------------------------------------------------------------------
By all that you hold dear on this good Earth
I bid you stand, Men of the West!
Aragorn

Hmm, I'm having trouble posting on this thread...

OK, a very brief summary of what I've been trying to post.

I concede Dr. Schilling's point that Mars orbit could be economically
feasible, but I still don't see how it compare to near-Earth
operations. It cannot manufacture on demand for near-Earth operations
due to infrequency of launch windows. Plus, there's the expense of
long transits for reusable spacecraft compared with week-long missions
in near-Earth space. Fewer passengers per spacecraft tonne per year.
You want to stay at Mars, but this has to compete with the difficulty
of getting there. Space may not be properly settled for a long time,
transient populations at Lagrange and lunar habitats may be the case
(oil rigs).