Re: cheap lunar gear & base (spin-off of superhero flight)

On Mon, 14 Apr 2008 16:38:28 GMT, Bryan Derksen
<bryan.derksen@xxxxxxx> wrote:

Leonard Erickson wrote:
On Mon, 14 Apr 2008 07:45:07 GMT, Bryan Derksen
<bryan.derksen@xxxxxxx> wrote:
If you use pure oxygen to fill the habitat you'll have much less than a
full atmosphere of pressure, so that'll help ease the stress on your
door too.

No thanks. I'm old enough to remember the Apollo 1 fire.

The Apollo 1 fire happened not just because of a pure oxygen atmosphere,
but because they used a _16 psi_ pure oxygen atmosphere. They needed to
test the spacecraft's ability to hold pressure in a vacuum, but since
they were testing it at sea level they had to pump it up with
higher-than-sea-level pressure inside to do that. In space, pure oxygen
atmospheres are only around 3 psi. The lack of nitrogen as a buffer gas
would make fires a bit hotter but you wouldn't get an instant
all-consuming infero like Apollo 1 did.

No, but it'll be at least as bad as an oxygen tent fire.

Gibven that the materials easily scrounged may be things like wood and
plastics, I'd not want to risk it.

Besides,
plants will do an okay job of air renewal once they've got reliable
power.

It's actually a lot trickier than it seems to get this to work. Google
for "CELSS" (Controlled Ecological Life Support System) to find work
that's been done on this area. Plants will certainly be nice to have
around, for psychological reasons if nothing else, but you're still
going to need to worry about CO2 scrubbers and bringing more oxygen up
from Earth over the long haul. When your ecosphere is only the size of a
small house it's got too little inertia to strike a balance easily.

They'll help a lot. And if you pick things that are edible raw, it's
nice for snacking. (Fond memories of the tomato "bush" a friend had.
The tomatos varied from pea sized to grape sized and were delicious.
Also bore them for *months* ripening a handful or so a day. :-)

You want higher pressure for that as well as well as avoiding
decompression problems.

You're unlikely to get the bends from a 0.8-atmosphere drop in pressure.
That's the equivalent of coming up from a dive of 26 feet depth. Digging
around a bit, I found a website suggesting that divers don't need to
bother with decompression unless they go under 130 feet down.

There'll be unpleasant ear-popping, perhaps, if your teleporter is
switching air pressures instantaneously. Perhaps she should teleport to
a mountaintop first in order to give her ears and sinuses a few seconds
to drain of excess air. Can she teleport into mid-air higher than that?

Also not good for sodas, many packaged foods and even a lot of
computer stuff.

Alternately, since mass is so cheap in this scenario, you can just
over-engineer everything to such a degree that holding a full atmosphere
of pressure isn't a major concern. :)

See my multilayered wall idea in the original thread.

Though I'm wondering if a concrete sealer that's rated for arctic
conditions might not be a good start.

An airlock will probably be needed; if the super isn't super-strong he
won't be able to open the hatch against atmospheric pressure, and the
super needs to be able to get in and out without blowing all the air and
killing the visitor in the process. This should be just a matter of
installing a second hatch and putting valves in them to allow pressures
to be equalized.

Well, depending on difficulty of making the hatches, the multiple
hatch solution might be good.

And once it's airtight and has decent supply of air and is at a
reasonable temp, the teleporter can help with some things.

If the teleporter is able to take the super as a passenger and is always
available when the super will need to get inside the base, it might be
best to not bother with hatches at all. Dig the cave in a vacuum, bring
in the teleporter to familiarize her with the location, then seal the
entrance completely. If you want solar power make sure to leave a cable
running through the plug.

I thought about that, but she needs to be able to get in on her own.
This may be easier to solve if it takes long enough because I do
figure on her getting stronger as she figures out some "tricks" of the
"forcefield" on the skin that does the "invulnerable" bit.

More strength means more cargo. As well as the ability to use some
brute force solutions.

Either way, hauling up enough pressure tanks for "just in case" will
be a chore, but doable.

What would worry me most is carbon dioxide and monoxide buildup. Just
adding more O2 to the air doesn't get rid of that, and plants are very
slow. Make sure to bring some monitoring equipment with you to keep an
eye on that.

Compressed air. Much easier to get refills for.

CO is easy, just buy (or shoplift) a monitor.

CO2 is harder. But easily handled by bubbling air thru a calcium
hydroxide solution.

Activated charcoal to deal with all the *nasty* trace gases that build
up is another need. Especially with non-space rated sealers and
materials.

A dehumidifer will be needed if they spend much time there.
.

Relevant Pages

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    ... but because they used a _16 psi_ pure oxygen atmosphere. ... test the spacecraft's ability to hold pressure in a vacuum, ... There'll be unpleasant ear-popping, perhaps, if your teleporter is ... switching air pressures instantaneously. ...
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  • Re: cheap lunar gear & base (spin-off of superhero flight)
    ... The Apollo 1 fire happened not just because of a pure oxygen atmosphere, but because they used a _16 psi_ pure oxygen atmosphere. ... They needed to test the spacecraft's ability to hold pressure in a vacuum, but since they were testing it at sea level they had to pump it up with higher-than-sea-level pressure inside to do that. ... There'll be unpleasant ear-popping, perhaps, if your teleporter is switching air pressures instantaneously. ...
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