Questions about "The High Frontier"

"Matthias Warkus" wrote in message
...

Certainly; only there is so much solar power coming through the atmosphere
already that can be captured in pretty simple ways

The primary problem is not atmospheric scattering. It's that the sun sets
every night.

--


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

Pat Flannery schrieb:

For starters, the reason they are going to exist isn't to give people a
really fun place to live, but make a buck.

True, but consider that maybe after SPS construction is in the black, there
might be a buck to be made providing Earthlings with a really fun place to
live.

Granted, that's predictated on two, perhaps three orders of magnitude
reduction in costs (and I mean even over what you have with the initial SPS
program), but mass production can work wonders.

--


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

"Matthias Warkus" wrote in message
...

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.

It doesn't work to provide continuous base-load electric power.

Don't bother to bring up storage methods. That's not solar, but solar plus
something else.

--


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

Pat Flannery wrote:

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

The math is over he
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 page uses the same approximation in the approximation I used.

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..

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.

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

The swelling returns to normal when normal pressure is resumed, as that
page indicates. The point is, none of the things you described happen
unless the victim is doing something incredibly stupid, and something
presumably anybody in the circumstances would be trained not to do.

--
Erik Max Francis && && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
Bring me men / Bring me men to match my plains
-- Lamya

On Tue, 02 Oct 2007 23:03:02 -0500, 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,

Why? Wealthy, highly-educated populations (i.e. any plausible group of
space colonists) tend to breed at less than replacement rates, and half
a million kilometers of vacuum tends to be a pretty effective barrier
to immigration. The only "population control" mechanism I see any need
for, is a public debate over how much to subsidize immigration and/or
native babymaking.


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.

Yes, actually, it would. The population of the space habitat would be
in no particular danger of suffocation. What would happen is, sometime
later that day a couple representatives of that population would knock
on your door and say, "you're leaking air; can we come in and fix it?"

On the outside chance that you said "No", it's an interesting question
whether they would A: break down your door and fix the leak anyhow, B:
lock your door from the outside and seal it up nice and airtight, or C:
order supplimentary air shipments from a neighboring habitat and bill
them to your account. Depends on the fine details of the habitat's
legal, political, and economic set-up. But either way, the only one
who'se in any danger of suffocation is you.

And, really, not even you. Because you aren't going to secretly drill
a hole in the wall, and none of your neighbors believes you are liable
to secretly drill a hole in the wall. The security measures and legal
restrictions that people actually put in place, tend to be based on the
sorts of misbehavior that actually exist or that people believe are
likely to actually exist, not silly thought-experiment examples of what
could exist but doesn't and isn't expected to.


This sounds like a perfect set-up for something a lot more like a
fascist state than a libertarian paradise.

If a bunch of fascists establish the space colony in question, sure.

People, in the short term at least, are a lot more amenable to the idea
of reshaping their environment to fit their desires than vice versa. Any
space colony, habitat, whatever, is going to reflect the desires of the
people who build it - in political and socioeconomic as well as physical
structure.

If it happens to be built by libertarians, then it will have a libertarian
political and socioeconomic setup; nobody is going to be demanding any
sort of fascist police state on account of they're afraid their fellow
libertarian space colonists are going to secretly murder them in their
sleep and they can't think of anything less than a fascist police state
capable of stopping that. And, you know, I'm pretty sure that if it is
ever put to the test, the libertarian space colonists will not in fact
be murdered in their sleep by their fellow libertarian space colonists
going around drilling holes in the walls or whatnot.


--
*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 *

On Thu, 04 Oct 2007 22:54:06 -0500, Pat Flannery
wrote:


Mike Combs wrote:
How many editions was "High Frontier" printed
in? Are you reading the same one as I am?

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.

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...

I get a half-life of seventy-six hours for the habitat atmosphere, and
as one can breath in half an atmosphere in a pinch, that leaves at least
three days to plug the hole.


trying to fix the hole has the problem of getting near the hole while
trying to avoid being sucked into it

So just stand about ten feet away, in the nice five-knot breeze, inflate
a four-foot rubberized kevlar ballon from the emergency kit, and let it
fly. After that, tear open the bag of styrofoam packing beads. Then go
have a nice cold beer and sit down to plan more permanent repairs.


(the noise near the hole should really be impressive also)

Oh, No! Our home is DOOOOOOOMED!!! because the part that needs fixing
is, like, really noisy and we forgot to buy earplugs.


and the extreme discomfort caused to the populace as the air pressure drops.

The extreme discomfort caused by air pressure dropping at roughly half
the rate experienced by a ground sloth climbing a staircase.


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.

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

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

Obviously. Which means your opinions are absolutely, completely, totally
irrelevant to the decision of what sort of legal and/or security measures
to put in place in such a habitat.

Fortunately for all concerned, the people who *are* going to be doing that
sort of thing, are for the most part actually capable of doing basic math.


--
*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:

I get a half-life of seventy-six hours for the habitat atmosphere, and
as one can breath in half an atmosphere in a pinch, that leaves at least
three days to plug the hole.

Hmm, I get about 31 hr = 1.3 d for the half-life (taking into account a
proportional drop in pressure as the vessel drains, and assuming that
it's adiabatic).

But that doesn't really change your larger point.

--
Erik Max Francis && && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
Victory is a very dangerous opportunity.
-- Gen. Andre Beaufre

On Fri, 05 Oct 2007 16:58:08 -0700, Erik Max Francis
wrote:

John Schilling wrote:

I get a half-life of seventy-six hours for the habitat atmosphere, and
as one can breath in half an atmosphere in a pinch, that leaves at least
three days to plug the hole.

Hmm, I get about 31 hr = 1.3 d for the half-life (taking into account a
proportional drop in pressure as the vessel drains, and assuming that
it's adiabatic).

Let me guess: you were assuming the hole had a cross-sectional area of
one square meter instead of a diameter of one meter, and that air flowed
through the hole at the density and speed of sound of air at rest in the
habitat interior.

The air *does* flow through the hole at the speed of sound, but by the
time it gets to the hole it has expanded and cooled, so you aren't
losing air as fast as you think.

If you want to skip the fluid mechanics, just tack a factor of one-half
on the "area of hole times density of air times speed of sound" BOTE
calculation.


But that doesn't really change your larger point.

Right.

John Schilling wrote:

On Fri, 05 Oct 2007 16:58:08 -0700, Erik Max Francis
wrote:

Hmm, I get about 31 hr = 1.3 d for the half-life (taking into account a
proportional drop in pressure as the vessel drains, and assuming that
it's adiabatic).

Let me guess: you were assuming the hole had a cross-sectional area of
one square meter instead of a diameter of one meter,

Nope.

and that air flowed
through the hole at the density and speed of sound of air at rest in the
habitat interior.

Yep, since it was a back-of-the-envelope calculation.

The air *does* flow through the hole at the speed of sound, but by the
time it gets to the hole it has expanded and cooled, so you aren't
losing air as fast as you think.

If you want to skip the fluid mechanics, just tack a factor of one-half
on the "area of hole times density of air times speed of sound" BOTE
calculation.

So what's the full calculation, then?

--
Erik Max Francis && && http://www.alcyone.com/max/
San Jose, CA, USA && 37 20 N 121 53 W && AIM, Y!M erikmaxfrancis
The conviction of wisdom is the plague of man.
-- Montaigne

Mike Combs schrieb:
"Matthias Warkus" wrote in message
...
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.

It doesn't work to provide continuous base-load electric power.

Don't bother to bring up storage methods. That's not solar, but solar plus
something else.

Uh, yes. All forms of power generation need a distribution grid and
buffer storage of some kind. Your point being?

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