Questions about "The High Frontier"

What really bothers me is that the entire scheme seems too much like
something out of a Rube Goldberg cartoon. "We'll build a base on the
Moon to deliver material to Earth orbit -- and we'll need at least
some mining ships scouting the asteroids for water and organics too --
which will be used to build a 3-million ton, 10,000-man space station
the size of Manhattan; then that will build 80,000-ton satellites, and
those will transmit solar power back to Earth." (He offers other
justifications for his "Islands" -- building space telescopes, for
example -- but it seems that we've achieved most of those goals
already without them.)

I suppose I want to start off by asking, "Would a Solar Power
Satellite work in the first place?" I know that the idea has gotten a
lot of flak recently; is it still viable or just hopeless?

It's certainly technically viable. The issue is whether or not it is
economically viable, relative to the competition.

I've the original book; as I remember it, it wasn't so much a political,
economic, or social system he was promoting as much as the technology of
using space colonies for large scale manufacturing due to the advantages
of large amounts of free solar power, while at the same time preserving
Earth's ecosystem by moving large-scale industries off planet to cut
down on pollution.
It was only after the book that every Tom, Dick, and Harry with a
political or economic axe to grind began looking at space colonies as
some sort of do-it-yourself Utopias where the innate superiority of
their political or economic system would no doubt be shown to all.
Once the likes of Timothy Leary got involved in the space colonization
hypothesis, the thing was screwed... they promptly turned into something
like a religion or revolutionary political movement.

Yeah..."if you build it, they will come." That was the same rational
used for SST's, commercial flights on the space Shuttle, and in the
1800's for Brunel's Great Eastern steamship.
Today, you can see an echo of it in the Space Tourism industry.

You can do it; but it is going to be anything but cheap to do.

Pat

The only way you could start off in space is to start off small. Like
Bigelow Aerospace's Sundancer module; yet it's also suffering from
that "if you build it, they will come." However, the desire for space
stations is there, and with smaller space programs like India and
China wanting their own in the next few decades, certainly the desire
for that inflatable technology will be there. O'Neill proposed that
the "small" gap would be filled by shuttles, funded by the government
and quickly scaling up to massive projects. I suspect he also figured
in economics of scale effects, as well. Only massive government
funding would be able to kickstart such a project.

Yet, his reasoning is sound - big projects do happen. However, if they
are not commercially viable (and there's no way that SPSs would be for
many many decades), they'd better be religiously significant,
militarily important or just the work of a cray rich megalomaniac.
Without that, launch costs had better be about $200 a kilo or less for
lunar/asteroid mining to become viable for supplying materials - just
to earth orbit. Building O'Neill colonies from refined lunar dirt...
unlikely. Real colonies would be built more simply (eg hollow
asteroid), be smaller, and less ambitious. From there it would be a
gradual scaling upwards. I see the first colonies as being in low
earth orbit as some kind of space hotel / servicing centre hybrid.

Obviously you haven't had words with William Mook, the leading wizard
on such things.

I'll also provide the necessary tethered platform, along with all the
clean energy for driving those nifty SBLs as energy cannons, all
situated at the end of my tether dipole element that's associated with
my LSE-CM/ISS. I was planning on hosting a dozen 100 GW class of such
laser cannons, thus 1.2 TW of which roughly half of that energy gets
onto our terrestrial grids.

Of course there are other uses for such SBLs.
- Brad Guth -

That's why a cool POOF City worth of those "Bigelow Aerospace's
Sundancer modules" would more than do the trick as situated at Venus
L2.

VL2 POOF City is offering much better than all of those, and it's even
more so viable as our first interplanetary geteway, especially since
our moon's L1 is still so taboo/nondisclosure rated and being rather
gamma and X-ray naked to the raw exposure of our anticathode moon,
plus otherwise our moon's L1 being unavoidably hot as hell (requiring
an artificial solar shade, whereas even the secondary/recoil worth of
IR from the moon itself is substantial)
- Brad Guth -

That's almost entirely a question of scale. Solar Power Satellites
can be built and will work as advertised, it's just that if you read
the fine print in the advertisements, the things only work well at
power levels of several gigawatts or so. Anything less, and you run
into problems with the relative size of the antennas for power beaming
from desirable orbits. Or, alternately, the seriously inconvenient
duty cycle and load sharing problems associated with the crappy orbits
you're limited to with small antennas.

Multiple-gigawatt power satellites are huge enough that we'd need a
whole lot of new infrastructure to even start building them, and new
productive infrastructure is rarely worthwhile unless you're going to
produce at least a dozen or two of the whachamacallits in question.

So, given someone who says, "I've got half a trillion dollars here,
I desperately want/need a hundred gigawatts of electric power, and
I can't find a cheaper terrestrial solution", yes, something like
O'Neill's architecture follows pretty naturally. And it's probably
even profitable in competition with terrestrial power generation.

But if all you've got is half a billion dollars and you just want
to prove the concept and/or get yourself a hundred megawatts of
juice, it doesn't work.

Oh, and multiply that half-trillion dollars by a factor of ten or
so, ruling out any hope of profitability, if you put a government
agency in charge of the program.

Mind you, some of the same problems apply to nuclear power, and we
do have that. But much of the necessary infrastructure there is
common to existing coal-fired powerplants, and much of the rest is
shared with the nuclear-weapons people. And governments have a
well-established track record of pumping huge ammounts of money
into unprofitable weapons programs.

--
*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 *
*schi...@spock.usc.edu * for success" *
*661-718-0955 or 661-275-6795 * -58th Rule of Acquisition *

Not sure what you mean by "flak". I've read valid criticism of the idea
and have also seen misinformed criticism.

There was this recent article:
http://www.space.com/businesstechnology/070919_sps_airforce.html

I believe they'd be a good long term investment. In the short term other
energy sources are more economical.

Hop

No, sir; the copy I just read, at any rate, specifically promotes
colonies as bastions of individualism and freedom (although he
specifically avoids describing details of colonial government), and
also as a reservoir for Earth's population growth (which would at this
point have to be 200,000 people shipped out to L5 _every day_).

Yes, "criticism" is what I ought to have said, but it was late and I
was tired. ;)

Your article reads, "Rouge said that moving out on the proposed SBSP
effort would be the largest space venture yet, making the Apollo Moon
landing project 'look like just a small little program.' As a caveat,
however, he noted that the U.S. Department of Defense is cash-strapped
and is not the financial backer for such an endeavor." The US DoD
recieves some $300-$400 billion-with-a-B every year. I wonder if
anybody else can afford an SPS project, if they cannot.

Well, that answers my next question: why, if an SPS works, does it
have to be so big? Many thanks.

>On Oct 1, 2:10 pm, Pat Flannery <flan...@daktel.com> wrote:

That's not so many. More people probably transit daily through the
three largest US airports than that.

Of course, the growth is set to decline and go negative later this
century, by the time such colonies would be built.

SPS that operated at optical frequencies could be much,
much smaller. So SPS proponents should support continued
work on efficient solar-pumped lasers and laser-to-electricity
conversion devices.

Paul

There's a huge and glaring logical flaw with the idea of large
scale colonies in space. If we can't learn how to sustain ourselves
here on earth, with all the natural advantages and cheap resources.
How in the hell are we going to produce a sustainable colony
in space?

The wisdom and technology needed to produce large scale
colonies renders them irrelevant.

The true test of an enlightened civilization is to be able
to sustain itself indefinitely. Not to simply find more room
for unsustainable societies.

Why do sci-fi writers assume we must move into space to survive???
The facts on the ground strongly suggest that as societies become
more advanced and affluent, the population growth slows to
sustainable levels.

I think the upcoming Olympics in Beijing will provide a glimpse
into the priorities of the future. China burns so much coal that
it's air is almost deadly. Dear Mother Nature will give us a
few very calm days in Beijing so the world can watch
the athletes flee the city for their very lives.

As oil and natural gas continues to rise every day, as the
third world continues explosive industrial growth, the third
world will turn to coal, and pollute us into desperation.
Solar power will then no longer be a matter of cost/benefit.

But a matter of survival.

http://en.wikipedia.org/wiki/Environment_of_China

I think John Schilling did a good job of explaining why SPS need to be big.

You might be thinking of Island 3, but remember that even when talking about
Earthlike space habitats, the first-generation ones would only have
populations of 10,000. That's small as many cities go.

It might interest you to know that after The High Frontier was published,
O'Neill turned out other studies where small, simple "space manufacturing
facilities" and construction of SPS came first. Lush, Earthlike habitats
came much later in the program, and then only with the understanding that
once you had mining facilities on the moon and/or asteroids and
manufacturing facilities to construct SPS in space, most of what you needed
to build large habitats is pretty much already in place and amortized.

Interestingly, the military seems to have revived interest in this concept.
http://www.space.com/businesstechnology/070919_sps_airforce.html

--

Regards,
Mike Combs
http://members.aol.com/oscarcombs/settle.htm
----------------------------------------------------------------------
By all that you hold dear on this good Earth
I bid you stand, Men of the West!
Aragorn

It might have been T. A. Heppenheimer who said, "Space colonies are a kind
of political Rorschach test".

But I am sanguine about space habitats as political experimentation
laboratories. If one's society ultimately fails (or just consistently
performs poorly), it would have to be a result of its underlying philosophy.
In a space habitat, one could hardly blame resource depletion, an energy
crisis, population pressures, a crop failure, or inconvenient location.

--

Regards,
Mike Combs

>There's a huge and glaring logical flaw with the idea of large

All of the available evidence indicates that we are quite successful
at sustaining ourselves on earth.

This coming from someone that doesn't see any problem
with co2 increasing at 2% a year...and accelerating.
But maybe you're right, everything on the planet is
just fine. But keep your head in the sand, with a little water
maybe something interesting will sprout.

It may be deadly in the long term but it's hardly going to send atheletes
fleeing after just a few weeks. It's ugly and sometimes smells bad but
I've never dropped dead from short-term exposure to it, and those guys are
in way better shape than I am.

--
Michael Ash
Rogue Amoeba Software

Doesn't matter, 'cause it won't happen that way.

When you consider the gargantuan capitol investments were talking
about in building such machines, even once we're able to do so, the
chances that they'll be given out to fringe movements or minority
groups to 'experiment' with strains credulity.

Shermanlee

Yeah, but they also thought bees sticking their tongues out was a viable
means of detecting explosives and chemical weapons:
http://rapidrecon.threatswatch.org/2007/02/bees-in-a-box-buzz-bombs/
They've got enough troubles already in Iraq between the sectarian
killings and the cholera without turning huge swarms of bees loose on
the populace. :-)

Pat

Your impression, unfortunately, is dead right. It _is_ a Rube
Goldberg scheme of the first order.

The thing you have to understand is (IMHO of course), the point of the
exercise for O'Neill is not energy, it's the space habitats as an end
in themselves. The idea of selling electricity is simply an attempt
to come up with a plausible reason to build the Habitats. In a way
that puts O'Neill into a less dreamy category than some space
enthusiasts, he at least recognizes that there has to be an economic
incentive in it all somewhere. But it's still pretty doesn't work.

If the primary goal were to build SPS, then the Habitats are
extravagances of the first order, you could achieve the same thing
more cheaply with orbital hotel type structures, utilitarian
facilities designed to house a rotating construction crew on a medium-
term basis. For a comparison, think offshore oil platforms. They
aren't luxurious, but they are tolerable/comfortable for a rotating
crew. To draw out the comparison (which I grant is imperfect),
imagine if someone proposed that the key to exploiting off-shore oil
resources was to construct floating towns that were ecologically self-
sustaining and designed to duplicate suburban living out of an
advanced Western state at sea.

O'Neill's plan called for totally unrealistic space access by the
standards of the 70s, he was assuming not only that the Space Shuttle
would live up to NASA's hype, but that it would do _better_ over time,
and he was assuming radically unrealistic constructions costs at every
stage of the game, including assuming the availability of working
models of technology that just hadn't been proven yet (and much of it
still hasn't been.)

What really makes me a critic, though, is not that O'Neill dreamed
big, I admire that. The problem is that his dreams became so hyped
that they actually became a negative force from a POV of space
exploration and development. Critics used them as 'proof' that the
entire concept of space exploration/exploitation was silliness, empty
pipe dreams, while they raised supporters expectations to levels
guaranteed to be disappointed.

The primary requirement for a space habitat is to provide a pressurized
environment. That takes lots of tensile strength. Regolith has little or
no tensile strength and even solid rock doesn't have enough. Even glass is
much better, and steel and aluminum more so. So if we wind up building a
steel or aluminum shell inside the asteroid to provide the pressurized
environment, we have to ask what is the asteroid providing. Radiation
protection? Fine, but we can get that with a shell no more than 6 feet
thick. If we remove a certain amount of raw materials from the asteroid and
refine it to glass, steel, and aluminum, the left-over slag is sufficient
material for that 6 foot thick radiation shield.

Yes, I'm entirely open to the idea that space habitats, instead of springing
full-blown from a single project as O'Neill envisioned, might evolve as a
series of incremental improvements to space hotels. We get to the 10th
generation space Hilton, with its rotation for artificial G, its full
radiation shielding, its closed ecology, and perhaps even use of natural
sunlight, and people will suddenly go, "Hey, this is like that old Island
One notion O'Neill was talking about back in the 20th Century".

Why would just the athletes flee? Why not everyone else? Are only the
athletes' lives in danger? Why aren't people fleeing now?

Jim Davis

Population growth is a _good_ thing in the long term, survival-wise,
population decrease is a sign of a declining society and even stablity
is death in the long haul. Survival _requires_ growth and expansion,
because sooner or later something unlikely in the short term but near-
certain the long will do bad things to any given habitat.

A tribe of primitives could exist in 'sustainable' balance in an
ecological niche for ages, but if they stay there and don't expand
sooner or later something will get them, a volcanic eruption, disease,
earthquake, something. A group in 'sustainable' balance over an
entire continent would likely last longer, but again, sooner or later,
they'll fall to a supervolcano or a meteorite or a massive climate
shift, no niche is permanently stable.

A planet-wide 'sustainable' state is better yet...but again, sooner or
later you'll roll snake eyes. Your star will change, there'll be a
nearby supernova, a _big_ impactor may (actually given enough time I
should 'will', not 'may') come your way, or something we don't even
know about might happen, but again, on the open-ended time scale the
imperative remains: grow or die.

In my copy I'm reading about the fact that in a lot of ways, life on a
habitat would be considerably less free than on Earth.
Population would have to be strictly controlled, and any form of
dissidence that could present a danger to the habitat stopped in its
tracks. If I decide to secretly drill a hole in the ground here on
Earth, its unlikely the whole population of Jamestown, ND will
suffocate; that wouldn't be the case on a space habitat. This sounds
like a perfect set-up for something a lot more like a fascist state than
a libertarian paradise.

Pat

As I noted above, for O'Neill the Habitats were the point, and yes,
there is a contradiction between his libertarian ideals and the
realities of what would be necessary to actually create the things. I
suspect he sensed that, and tried to create a convincing sleight of
hand to hide it from himself.

You could actually make a plausible case that an O'Neill Habitat would
of necessity be a highly _disciplined_ environment, certainly the
option of leaving if you don't like how things are run would be much
trickier in an O'Neill than on Earth. Most of the idealistic
component of the whole concept is more about dreams than thought.

That's a very good analogy; everyone sees in them what they want to.
Utopia or something like living in a giant tin can?
Amazingly enough, there is a very close analogy to living in a space
habitat here on Earth - a place untouched by most laws, where everyone
lives in fairly close quarters in the middle of a hostile environment
with only fairly rare visits from outside groups; that being the
Antarctic science stations. I've talked to two people who were stationed
at them, and they didn't exactly compare them to a vacation on the
French Riviera.

How about if a neighboring colony blows a hole in yours to let the air
out, then seizes it for their own, as they want to increase their
population?
The other problem is political extremists and Utopian true believers;
the concept of little flying political laboratories is going to attract
those two groups like bees to honey, and a political uprising inside of
a space colony has a real potential for getting its entire population
killed.
The people it is going to attract are the last ones you would want on
board, rather like what happened to the L5 Society itself.

Pat

They'll probably be run very similar to a military model; a very strict
rank hierarchy and everyone being assigned their jobs and knowing who
they take orders from. That hardly sounds like a Utopia, more like life
on a Nimitz class carrier.
For starters, the reason they are going to exist isn't to give people a
really fun place to live, but make a buck.
Other than a business venture, about the only way you can see one
getting built is a cult leader getting money from his followers to build
the place on divine orders.
Places like that seldom come to a good end.
If they're lucky, it ends up like the Amana Colonies with everyone just
losing interest: http://www.nps.gov/history/nr/travel/amana/utopia.htm
If not, it ends up like Jonestown, with everyone jumping out the airlock
to show their devotion.
I imagine step one is for any prospective designer of one is to read
Plato's "Republic", and avoid the Book of Revelation like the plague.

Pat

He also assumed the development of huge reusable heavy lift boosters if
the SPS constellation was to be built using Earth-launched materials,
and if it ever is built, that's almost certainly the way it will be
done, rather than going to all the trouble of building the Lunar
infrastructure.

That probably had a lot to do with the enthusiasm shown by the aerospace
industry for the concept; they full-well knew that the thing was wildly
optimistic...but on the offhand chance it would get funded, they were
willing to to play it up as a brilliant idea, because it would make the
Apollo program look like a minor project by comparison.

Pat

They can't. Their lead content is so high that they've become immobile
due to their mass. Even their pet dogs have been crushed flat under
their own weight: http://tinyurl.com/cftp

Pat ;-)

Population growth on Easter Island wasn't a good thing, nor in many
areas where it led to soil depletion via overfarming to support a
burgeoning population throughout human history.
I did the math on this once, there were around 8.5 city blocks per
person for everyone on the face of the planet, and that included using
the seas as surface area also:

> that this is the total surface area of the Earth, not just the land
> masses:
> "Here's another way of looking at it; the total world population is
> around 6,490,115,551 as of this morning:
> http://www.census.gov/main/www/popclock.html
> The total surface area of the earth is 196,940,400 square miles:
> http://pages.prodigy.net/jhonig/bignum/qland2.html
> So if we take divide that population by that surface area we end up with
> an average of around 33 people per square mile of the Earth's surface.
> Now there are a total of 27,878,400 square feet in a mile, so we end up
> with one person for around every 844,800 square feet of the Earth's
> surface, or to put it another way, around one person for every 8.5 city
> blocks, which although they vary wildly in size tend to cover around
> 100,000 square feet total on average (assuming they are a tad over 300
> feet on a side)

Take the oceans out of that equation and you are starting to get near
the point where we have only enough area to support our total population
via farming, particularly when areas unsuitable for farming (mountains,
forests, deserts) are taken into the equation.
When you move out into space in any large numbers, the amount of area
required for food production starts to look pretty daunting,
particularly if you want a varied diet including things like meat and
cheese, although I imagine a lot of things could be made in a synthetic
form.

Pat

The concept I was thinking of is Niven's asteroid balloon. Take an
iron asteroid, place water tanks at the centre, spin asteroid on its
axis and bathe with concentrated sunlight from a solar mirror. Tank
explodes, inflates molten steel asteroid into a large habitat. Most
asteroids are just soft rubble piles anyway; they'd fly apart if you
spun them any faster than once every 2 hours. Some sort of melting has
to be done on the outer shell to stop one disintegrating;
additionally, internal structural bracing such as steel cables are
required to hold it together, especially if you want nice amenities
like dirt and artificial gravity.

O'Neill also mentioned spray-on space-based structures. That could do
nicely for manufacturing large (100m) habitat modules. However, the
Island One design is wildly extravagant - it would take many decades
of settlement for habitats to become anything like comfortable.

This has always struck me as implausible. It's hard to see how most, or
even a few, nickel-iron asteroids would be uniform enough to make this
work without just fracturing during the process, wrecking the whole
enterprise.

--
Erik Max Francis && m...@alcyone.com && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
Come not between the dragon and his wrath.
-- Shakespeare, _King Lear_

We have, infact, been sustaining ourselves here on earth for quite a
while already thankyouverymuch. We've known how to do that trick since
literally the first day a human ever walked the earth. If we hadn't,
we'd be extinct by now.

Infact we've done a lot more than merely "sustain" ourselves. We've
spread and colonized every continent and just about every corner of
every continent. There is no other large mammal that even comes close to
being so widespread (I didn't say "numerous", though I suppose that may
-also- be true if we count only animals with an adult mass above 50kg)

Seems to me, by "sustain", you mean something different from sustain.
Perhaps you mean that unless we can live with no influence on the world
around us whatsoever, we're not "sustaining" ourselves. By that
definition no species has ever been able to "sustain" itself anywhere.

Both makes sense. Everyone here agrees that it's /easier/ living on
earth than elsewhere. But that's a bit like saying it's /easier/ living
in Italy than in northern Scandinavia, so it makes no sense for anyone
to be doing the latter. That is a strange kind of reasoning.

Most don't.

Eivind Kjørstad

There is another way to do an asteroid balloon that doesn't require the
asteroid to be anywhere near uniform, nor for you to drill into it (although
doing so would probably help).
Put a balloon (mylar, perhaps) around the asteroid, and fill it with carbon
monoxide. Get it warm and circulating. Then heat the balloon surface to
deposit nickel and iron from carbonyl vapor.

-l.
------------------------------------
My inbox is a sacred shrine, none shall enter that are not worthy.

>On Oct 2, 12:51 pm, "Mike Combs"

I know of no one who has proposed that they be "given out" to anyone.
The "fringe movements" and "minority groups" will raise their own
money to build them.

>> But I am sanguine about space habitats as political experimentation

The hole would be repaired long before the air went out. A hole big
enough to cause a total evacuation of the colony faster than it could
be fixed would be so big as to wreck the colony.

If colonies are affordable for "fringe groups," they're probably
sufficiently cheap that it makes more sense to build another one for
expansion than making war and stealing someone else's. It's not like
rare prime real estate.

A more likely cause of war would be ideological hatred. A Hamas space
colony would still plot ways to destroy the Jew space colony.

>Jonathan wrote:

Don't confuse jonathan with logic.

I pretty much agree with this but would like to elaborate.

Orbital structures like the proposed Bigelow hotels would be inadequate
for long stays as gravity is needed to maintain health. Crew rotations
are very expensive so you want to make them infrequent.

However small orbital hotels with artificial gravity may be possible. If
lunar gravity is sufficient to maintain health, the rotating hab radius
need only be 1/6 of the radius necessary for earth gravity.

Nyrath has mentioned recent research on tolerance to angular velocity.
It indicates humans can tolerate higher rpms if transition is gradual. 4
as opposed to 1 rpm would mean a sixteen fold difference in radius length.

So much smaller and less expensive rotating habs may be possible.

Hop

Yes, sir, but the number of people we've had living on a semi-
permanent basis in space at any one time is...maybe three orders of
magnitude lower. It does seem like a rather tall order.

> It might interest you to know that after The High Frontier was published,
> O'Neill turned out other studies where small, simple "space manufacturing
> facilities" and construction of SPS came first. Lush, Earthlike habitats
> came much later in the program, and then only with the understanding that
> once you had mining facilities on the moon and/or asteroids and
> manufacturing facilities to construct SPS in space, most of what you needed
> to build large habitats is pretty much already in place and amortized.

Thank you, I am interested! That was what I was thinking when I
closed the book: "If you already have a Moon base funneling resources
to a 2,000-man, 30,000-ton construction station, why not just use that
to build an SPS instead of building what amounts to an even bigger
construction station?" I don't suppose you have any references/links
I could study?

I see what you're saying, but curiously, that wasn't something that
O'Neill brought up. How many editions was "High Frontier" printed
in? Are you reading the same one as I am?

> Yet, his reasoning is sound - big projects do happen. However, if they
> are not commercially viable (and there's no way that SPSs would be for
> many many decades), they'd better be religiously significant,
> militarily important or just the work of a cray rich megalomaniac.
> Without that, launch costs had better be about $200 a kilo or less for
> lunar/asteroid mining to become viable for supplying materials - just
> to earth orbit. Building O'Neill colonies from refined lunar dirt...

> asteroid), be smaller, and less ambitious.

There are a few but not many asteroids you can land on for less delta
vee than reaching the moon. True, asteroids have very shallow gravity
wells, but the delta vee budget for reaching the asteroid nullifies this
advantage for most NEAs.

Asteroids tend to be more resource rich than the moon, there are metal
rich asteroids and also volatile rich asteroids.

NEA Launch Windows are infrequent. If the orbital period isn't close to
earth resonant, nice low delta vee trajectories could be very
infrequent. For an asteroid with a near earth perihelion and a 1.5
period, low-energy Hohmann windows could occur every three years. Launch
windows for very short but high delta vee "sprint" trajectories would
also occur each three years.

Most asteroids are quite massive. Altering their orbits for earth
capture is not possible with plausible near future rockets or mass drivers.

I agree with the gradual scaling upwards. If NEA resources are used in
this gradual process, they'd be payloads launched from an asteroid to
cislunar space. Trying to trap an entire asteroid to earth orbit would
be a major project, perhaps rivaling an O'Neill cylinder in scale.

Hop

> ... If one's society ultimately fails (or just consistently

I don't agree.

Should the cloud of habs spread through NEAs and the main belt, there
will be a wide spectrum of fortunes. Some colonies may be situated near
a two lobe asteroid, one lobe being nickel-iron rich in platinum group
metals, the other lobe having water, ammonia and lots of hydrocarbons.
This could be a very wealthy hab. Other habs may be eking it out near
big chunks of silicon.

Some habs may have trade economies. For example, if it's on a cycler
orbit that makes regular and frequent fly bys of Earth-Luna and also
Mars-Phobos-Deimos, they could export flora and fauna to Mars as well as
being a cruise ship to and from Mars.

The stage on which the human drama is played would be multiplied many
fold. As would be the opportunities for good fortune or bad.

Hop

And even if the habs all started out homogenous, all sharing the same
world view, they would diverge and schisms form. Especially if different
habs are separated by a large gulf. This is a recurring pattern in human
history.

Hop

Here's a nice article from NPR about air pollution and the
upcoming Olymics. The Olympic committee is already
threatening to delay or move contests out of Beijing
due to extreme air pollution there.

One quote;

In Washington DC, the pollution index is typically about 30-40.
At 60 health warnings would be issued.
At 90 people would be told to stay indoors.
The pollution index in Beijing is usually between
170 to 240!

Click "listen'
http://www.npr.org/templates/story/story.php?storyId=12638588

Who says they're not trying?

Air Pollution Grows in Tandem with China's Economy

"For Qiao Xiaoling, such bald statistics disguise the terrible
pain of loss. Her husband died four years ago from leukemia.
Then lung cancer claimed her 34-year-old son. As she minds
her 3-year-old grandson, she admits she doesn't know
what caused their illnesses.

"I don't know if it's because of the water or the air. I'm scared
in my heart and worry about this little boy. I think about
moving, but I don't have the money," Qiao says.
http://www.npr.org/templates/story/story.php?storyId=10221268

China Reportedly Urged Omitting Pollution-Death Estimates

By DAVID BARBOZA
Published: July 5, 2007
SHANGHAI, July 4 — Chinese government officials pressed the
World Bank into removing estimates of the number of premature
deaths linked to pollution in China from a bank report...

A formal draft of the report, “Cost of Pollution in China,” was
released at a conference in Beijing in March after the deletions.
The excised information included statistical models estimating
that as many as 750,000 people a year die prematurely in
China, because of air and water pollution.

> Jim Davis

>> I suppose I want to start off by asking, "Would a Solar Power
>> Satellite work in the first place?" I know that the idea has gotten a
>> lot of flak recently; is it still viable or just hopeless?
>
>The only way you could start off in space is to start off small.

Seems to me that starting off small is impractical for actual
colonisation unless your colonists are fine with living an
invertebrate existence. They have to be pretty big to make
pseudogravity practical and you can't effectively expand an
installation large enough to have significant gravity anyway. Seems
to me you have to build 'em the size you want them to be in
perpetuity, and then start 'em rotating, because once you inhabit
them, stopping them again isn't really an option.

So which is the lesser engineering/scientific challenge: full-bore
O'Neill Habitats, or using tethers to improve the rotation rate of
paired hotels? Or incorporating a centrifuge with a gym into the
hotel (which leads to the question of how much high-G activity it
takes of offset extensive lower G or microgravity).

I would like to see experiments done to establish just what levels of
gravitational attraction (or the equivalent) are necessary for Human
health, and what durations are dangerous. We just don't have the data
to make anything but WAGs on the subject as matters stand.

We still don't know exactly what did happen on Easter Island, contrary
to the claims of certain popularizations that portray a plausible
hypothesis as fact. It isn't even clear how long humans were living
on Easter Island prior to whatever went wrong.

That said, it's certainly the case that overpopulation can be a
problem _within_ a niche, temporarily. One way or the other, any such
problem will be corrected. In the larger sense, we can see in Easter
Island an example my larger point. Because they _were_ confined to
the one island, there was no margin for error if anything went wrong.
Their culture died in whatever disaster undid the local ecology. If
their culture was spread over other islands, it might have survived
the disaster.

(The larger Polynesian superculture _did_ survive various local
disasters such as Easter Island for a long period.)

Some may be, but the population in Beijing is growing enormously. There
was until recently a huge construction boom caused by a great demand for
housing, with new high-rise apartment buildings going up all over the
place. This has only stopped because the government prohibited new
non-Olympic construction in order to concentrate effort on what they think
is important and so that visitors don't get a bad impression of the city
due to a skyline crammed with half-finished construction.

So obviously most of the people either don't know, don't care, or think
it's a worthwhile tradeoff.

Very sad but if the plural of anecdote is not data, then the singular
definitely isn't.

> A formal draft of the report, ?Cost of Pollution in China,? was

"As many as" is a worthless phrase. If you must pick one number, pick the
median estimate. If you can, provide the error bars.

Even if true (brief searches indicate that the true number may be more
like 500,00) this is about ten times more pollution-caused deaths than in
the US, in a country with about four times as many people, for roughly
2.5x the death rate due to this cause. While that's certainly not good,
it's not nearly as horrendous as you make it sound.

--
Michael Ash
Rogue Amoeba Software

Let's get you on record here, Jonathan. You predict the 2008 Olympics
will not happen because of extreme air pollution. Fair enough?

Jim Davis

I don't think it's plausible, either, but it's (fairly) easy to handle
large masses in space. The point is to make big hollow pressure
vessels on a large scale. Perhaps just unpeeling the asteroid into a
larger habitat using solar mirrors is a lot easier. A semi-molten
asteroid with differing pockets of viscosity all the way through is
just gonna pop.

High-rpm-low-radius habs have a different problem though, the apparent
gravity inside them has a sharp gradient, and coriolis would be a bitch.

Wouldn't it be easier to hang the hotel on a tether, with a counter-mass
on the other end, and spin it ? (the counter-mass can be a second hotel
if desired)

That way you can have as small a structure as you like, with very low
rpm, and still whatever gravity is needed to maintain health.

Eivind Kjørstad

I've got the 1977 first edition by Morrow; start reading on page 198,
where the L colonies versus Utopias are discussed.
Although he says he isn't suggesting governmental policies on the L
colonies (and then goes on to do just that) he does point out that in a
lot of ways you are talking about a pretty controlled environment by
simple necessity.
The time frame of where the idea comes from is interesting; after the
counterculture communes of the late 1960s flopped and were looked back
upon as a great romantic dream that never panned out.
If you can't make it work in the real world...then build a new
world...literally, in this case. ;-)

Pat

As is war; and they can blow each other to hell with a single
non-nuclear weapon, provided that a political upset on board doesn't
lead to chaos and their own destruction as the factions fight it out
like two fish in a aquarium striving to be the first to blow up the
aeration system to put the other at a disadvantage.

Pat

Certainly; only there is so much solar power coming through the
atmosphere already that can be captured in pretty simple ways that the
immense cost of making powersats can only be justified if humanity's
energy consumption rises by something like several orders of magnitude.

mawa
--
http://www.prellblog.de

Think oil platform rather than aircraft carrier.

mawa
--
http://www.prellblog.de

Solar power is not the only clean renewable energy, but anyhow there is
no reason why non-orbital solar power shouldn't work. In fact it already
works just fine.

mawa
--
http://www.prellblog.de

People have held out in zero-g space stations for more than one year
without serious health problems AFAIK.

mawa
--
http://www.prellblog.de

Yes and no. Long-term stays require extensive exercise while in orbit (on
the order of 2 hours a day).

If we start to build SPS and the like, almost certainly some form of
rotating stations (or at least sleeping quarters) will be built.

> mawa
> --
> http://www.prellblog.de

--
Greg Moore
SQL Server DBA Consulting Remote and Onsite available!
Email: sql (at) greenms.com http://www.greenms.com/sqlserver.html

Yep, there it is. My mind must have glossed over it and focused on
his "principles and goals" back in the first few chapters.

See, this is why it's good to ask questions!

I'd think it cheaper to let people live in zero-g and put two hours of
mandatory daily exercise into their contracts.

mawa
--
http://www.prellblog.de

Around a year back, he was going on about some democratic revolution
happening in China during the Olympics IIRC.
This is a interesting fixation on one sports event or country.

Pat

You are going to have to stir it in a molten state to make it
homogeneous; could that be done via electromagnetic fields in the case
of a nickel-iron asteroid?

Pat

Difficult to dock with though. You could link up to the center of the
tether and slid down to the end you wanted, but the change in mass would
mean that the center of rotation would change, and the increase in
overall mass slow its rate of rotation down as the docking ship gets
spun up.

Pat

I still think that the Antarctic science stations are a fairly close
analogy, due to the fact that you have very long periods with no contact
with the outside world other than via radio or telecommunications, and
life outside the station can be downright deadly in if something goes wrong.

Pat

But the downside was it took hours of exercise per day to accomplish
that, as well as wearing a special suit that was uncomfortable and
restricted mobility by using elastic straps to generate forces the
muscles had to fight against.
This cut into both the time the crew had to perform useful work, and
made their stay on the station (Mir in this case) more unpleasant.

Pat

That's two hours less useful work they can do per day (unless you have
them run on a treadmill to generate electricity, I imagine), and they
are going to use up a lot of energy doing the exercise, meaning they
will tire faster and need more food and water.

Pat

Of course. But I think it's still cheaper than building a rotating
habitat unless there are *LOTS* of workers.

mawa
--
http://www.prellblog.de

Not only is it an odd fixation, it's also totally ludicrous.

Those people old enough to remember life before the Communists came to
power will rightly remember that it was a whole lot worse. The Japanese
were doing all kinds of terrible things and the Nationalists weren't
really very nice people either. Those people not old enough to remember
those times will still remember a nearly constant and extremely fast rise
in the standard of living and general conditions in the country. There are
probably some people with outspoken political beliefs who are quite
unhappy but for the most part the people there have no *reason* to want a
revolution, and every reason to avoid one. And while I'm as much a fan of
liberty and democracy as the next guy, I'd have a hard time saying that
they're wrong.

One such study just got uploaded to the web:
http://www.nss.org/settlement/L5news/1980-industry.htm

There were some proposals for small, simple habitats which rotated for
gravity for space manufacturing centers, but I note that this one features a
0-G habitat and assumes regular rotations to Earth.

This study mentions that 90% of the raw material for a SPS could be supplied
by the moon. A later study by SSI said that with a design optimized for use
of lunar materials, that percentage could be boosted to 99%.

--

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

Seems to suggest that Winkler was being overly-conservative when he insisted
that anything over 1 RPM would be a mistake.

And on top of that, China is increasingly implementing rule of law in
many areas. Apparently, in China you can these days *sue* a state-owned
company that wants to take your land and win. You could argue that at
present, there is more personal liberty in China than there ever was. It
seems they are also putting in place municipal elections and such?

It's a bit like the Prussian reforms, giving people more rights and
improving life for large segments of the population to *avoid* having to
install democracy on a national scale.

mawa
--
http://www.prellblog.de

I love O'Neill habitats with a purple passion, but the latter is doubtless
the lesser challenge.

It's a question of whether the goal is to house transient workers for
limited durations, or to settle space.

A rather tall order for a rather tall society which we assumed we were
living in, given that we had just landed men on the moon. Sigh.

> Thank you, I am interested! That was what I was thinking when I
> closed the book: "If you already have a Moon base funneling resources
> to a 2,000-man, 30,000-ton construction station, why not just use that
> to build an SPS instead of building what amounts to an even bigger
> construction station?" I don't suppose you have any references/links
> I could study?

http://www.nss.org/settlement/L5news/1980-industry.htm
The above is a summary. The other parts can be found here:
http://www.nss.org/settlement/manufacturing/library.htm#MIT

Yeah, past a point, O'Neill was happy to concede that nobody would start
thinking about large, Earthlike habitats until the
making-SPS-from-space-materials business was well into the black.

He can't be talking about The High Frontier, or any other book where the
author knows what he's talking about, as any such hole would still only mean
a blow-down time of many days (or weeks). Nobody's going to kill a large
population that way.

A mad bomber might manage to blow out a window pane or two (if he could get
at them). That's still a blow-down time measured in days; plenty of time to
implement repairs, and no cause for immediate evacuation.

So no, the logic is neither straightforward nor ironclad that "living beyond
the Earth" = "certain fascism".

Perhaps, but we needn't bring back the entire asteroid. Bringing back a
dislodged fragment or perhaps an enormous bag of loose regolith could get
orbital industries off to a fine start.

If we're building SPS, then we will have LOTS of workers and the ability to
build substational stations.

I never even thought of arguing that there's more personal liberty in
China than there ever was because it seems so *obvious*. It wasn't exactly
a bastion of freedom and democracy before the Reds Took Over, after all.

Of course that doesn't mean it couldn't be one now, look at what happened
in Taiwan and South Korea for example, but all in all the place is a lot
better off than it was.

I think that's the idea, anyway. I believe the Party realizes that making
people happy works better than making them afraid in the long term.
Ultimately it seems that people won't agitate for democracy or freedom
unless there is some *other* push, like poverty or extreme abuses of
power. Has there been a democratic revolution that wasn't pushed by
something else? Even the US revolution was prompted by taxes and dislike
of various aspects of British rule, with the whole freedom and democracy
thing being almost tacked on as a rider by people who saw the revolution
as an opportunity to make something really great.

After the slaughter at Tienanmen Square, the survivors let out what the
big plan was:
1.) Students will seize the square and demand democracy.
2.) The government will overreact, and there will be a bloodbath.
3.) The farmers will come in from the countryside and overthrow the
government.
4.) With democracy established, the students would be the obvious
intellectual leaders of the new political order.
5.) All things would then be wonderful and happy.
Parts 1 and 2 worked like a charm.
You read this, and you don't know whether to laugh or cry at the
incredible naiveté of it.
After the millions of deaths in The Great Leap Forward, the last thing
the people in the countryside wanted to see was any sort of political
upset, and a return to mass starvation.
I think that China will probably evolve into a pretty free culture with
time; say in twenty years or so.

Pat

Given how far into the future the date of construction is, it might be
able to be built almost entirely by robots at far lower cost than
building living quarters and bringing up supplies for human workers.

Pat

NASA did a study on this to determine the minimum diameter of a rotating
station where the crew wouldn't feel dizziness as they moved around in
it due to the perception of what "up" was, particularly in regards to
their inner ear.
IIRC, it was around 400 feet diameter for a 1g station.

Pat

It depends on the size of the habitat and the amount of air pressure it
has in it; not all of O'Neill's habitat designs were the size of Babylon
5*. Island One's living area consists of a sphere of 460 meters
diameter, and you blow a one meter diameter hole in the outside of that,
and the air is going to vacate it in well under a day...trying to fix
the hole has the problem of getting near the hole while trying to avoid
being sucked into it (the noise near the hole should really be
impressive also) by what's probably be like a tornado going into it, and
the extreme discomfort caused to the populace as the air pressure drops.
When Soyuz 11 depressurized through a valve around 1/2 inch in diameter,
the crew were incapacitated inside of ten seconds as the rapidly falling
air pressure burst their eardrums, caused their blood to start to boil,
and ruptured the alveoli of their lungs..
In the case of that 480 meter one at surface air pressure, you had
better hope you can get that repair crew to the hole inside of a minute
or two, as that's about all the time you are going to have before things
start getting very uncomfortable.

I'm just not keen on living in a giant tin can, fascism or not.

* Island Three was twenty miles long; four times as long as Babylon 5.

Pat

The timescale I get is about 50 hr, and that's assuming that the
pressure stays constant, which it won't; it will drop.

Hole has an area of 0.79 m^2, speed of sound is 340 m/s (presuming the
vessel is pressurized to 100 kPa), so the volume rate of efflux out the
hole is 270 m^3/s. Volume of the habitat is 5.1 x 10^7 m^3, so that's a
timescale of 53 hr.

That's still a short timescale, but that's a lot of time to do something
about it. And presumably if the size was really that small and such
holes were a serious concern, you'd have suits for everyone and/or an
air bunker of some time.

Not to mention that a 1 m diameter hole could really only be plausibly
caused by mischief.

Your blood doesn't boil, and you don't sustain any serious tissue injury
unless you hold your breath and/or clam your mouth and nose shut.

The _Soyuz 11_ accident doesn't really scale upward, because the cabin
is so tiny, and, if I recall correctly, it was in a place that they
could have done anything about anyway.

--
Erik Max Francis && m...@alcyone.com && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
The quickest way of ending a war is to lose it.
-- George Orwell, 1903-1950

Yeah, but not by much if all that slides is some passengers and some
deliveries. That's a tiny fraction of overall mass. If it's a problem
one would think it could be counteracted by having some movable mass
somewhere that can actively compensate. (say water that can be pumped
between two alternative tanks)

No. If you're docking with the centre of rotation of a rotating object,
obviously you need to be rotating with the same rpm as the object prior
to docking.

This ain't even complicated, consider that if you use the station you
want to dock with as your frame of reference, all you need to do is to
stop rotating -in-that-frame. It's not as if we're talking a lot of
energy here anyway, it doesn't need much of a push to set say the
space-shuttle up for rotating around its axis at 0.5 rpm.

Alternative solution is to have a docking-statin at the middle that does
-not- rotate. This has a few advantages. First, it can have more than 2
docks, since they don't need to be precisely on the center. Second, you
could hav any other facilities that benefit from zero-G here at the
centre too.

Eivind Kjørstad

The math is over here:
http://www.sff.net/people/geoffrey.landis/higgins.html
i want to see someone get near a 1 meter diameter hole with air getting
sucked into it at sonic velocities.

That was my intention, and why I stated that I was secretly digging the
hole.
Long time back, a friend and I were designing a space habitat, and were
looking for some way to detect small leaks that meteor impacts or other
faults could case in the outside wall of it.
Here's what we came up with; The wall of the habitat would be broken
down into a inner and outer wall separated by a few inchs and this
subdivided into a grid work of airtight cells by the structure between them.
Each of these cells would have a pressure sensor in it, and be
pressurized to less than the internal pressure of the habitat.
If pressure in one of the cells started to drop, it meant that it was
venting into space due to a leak in its external wall; if pressure
started to rise, it meant there was a leak in its internal wall.

Other than having your body swell to twice its natural volume,
convulsions, and having your circulatory system shut down of course:
http://www.sff.net/people/geoffrey.landis/vacuum.html

It was under the seats, and they had apparently figured that out by the
time they went unconscious, but it was too late to do anything about it
then.

Pat

You could have what grabs on to it be free rotating, and only it needs
be spun up to the speed of the tether during docking. Then gradually
spin up the ship to the rate of rotation of the tether by basically
using a clutch on the grab assembly, before starting to slide down the
tether to the end you want to reach. Unfortunately, if you use something
like a brake on it as you descend you are going to have to have the mass
of the ship be balanced someway on either side of the tether, or it's
going to Start twisting it as it descends.
It might make more sense to have the ship dock with the center of the
tether using a despun rotating grab assembly mounted on the tether
itself with a ring joint that things can be transferred through into a
pressurized chamber from where elevators carry it down to the crew areas
at the end.

Although that's the way the Pan-Am space clipper docks in "2001", I
think it would more sense from a simplicity viewpoint to despin the
docking assembly than spin up the docking spacecraft.

That makes more sense to me also; about the only problem you run into
then is getting the rotary joint to be large enough in diameter for
large cargo to pass through without leaking air.
It looks almost like something Escher would come up with, but Hermann
Noordung's* soler powered 1929 space station design uses a logarithmic
spiral set of stairs to allow a person at its center walk out to the
ring-shaped area where there is one gravity while staying heads-up at
all times. It also has a despun airlock at its axis to allow space ships
to dock with it easily: http://davidszondy.com/future/space/noordung.htm
Considering the timeframe this came out of, this was a downright
brilliant piece of work on his part.

* Real name, Captain Herman Pototc(nik

Pat

That page uses the same approximation in the approximation I used.