Questions about "The High Frontier"

Johnny1a wrote:


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.

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

On Oct 2, 10:43 am, "Mike Combs"
wrote:
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.

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?

On Oct 2, 9:03 pm, Pat Flannery wrote:
Damien Valentine wrote:
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_).

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

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?

Troy wrote:


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.


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.


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.

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

Mike Combs wrote:



... 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.

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

Rand Simberg wrote:



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.


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.

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

"Jim Davis" wrote in message
. 96.26...
Jonathan wrote:

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.

Why would just the athletes flee? Why not everyone else? Are only the
athletes' lives in danger?


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/s...oryId=12638588




Why aren't people fleeing now?



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/s...oryId=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

On Mon, 01 Oct 2007 23:44:57 -0700, Troy wrote:

On Oct 2, 2:45 am, Damien Valentine wrote:
So I just got through O'Neill's "The High Frontier". There seem to be
some philosophical inconsistencies -- O'Neill claims to be promoting
individual freedoms and small-scale economies by building monolithic
power satellites and kilometer-scale orbiting cities, for instance --
but that's neither here nor there.

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?

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.

On Oct 3, 3:32 pm, Hop David wrote:
Johnny1a wrote:
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.

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

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.

On Oct 3, 12:26 am, Pat Flannery wrote:
Johnny1a wrote:
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.

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.

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.)