Minimal space-suit

"Joseph S. Powell, III" wrote:

[snip]

How about a suit with tight leather straps all around - that should provide
the pressure, but you'd still need some type of helmet in a vacuum.

If you had a helmet with an O2 supply but no real suit, perhaps you could
wrap some Duct Tape around your body, reaaaal, real tight (over your
clothes ) and a jacket and snow pants or something similar over it - this
could possibly protect the duct tape from coming apart due to exposure to
the bright sunlight.
In a pinch, it's better than nothing, I suppose.

Sure. But then it's just a BDSM afficionado's idea of what others
have called a 'skin suit.'

If you had a helmet with an O2 supply but no real suit, perhaps you could
wrap some Duct Tape around your body, reaaaal, real tight (over your
clothes ) and a jacket and snow pants or something similar over it - this
could possibly protect the duct tape from coming apart due to exposure to
the bright sunlight.
In a pinch, it's better than nothing, I suppose.










If you had a helmet with an O2 supply but no real suit, perhaps you could
wrap some Duct Tape around your body, reaaaal, real tight (over your
clothes ) and a jacket and snow pants or something similar over it - this
could possibly protect the duct tape from coming apart due to exposure to
the bright sunlight.
In a pinch, it's better than nothing, I suppose.

Duct tape applied over clothing would not provide the needed pressure. And
your hands aren't protected at all; if you lose the use of those, in space,
you're dead (if you weren't already).

In k.net Anthony Q.
Bachler wrote:
There are other factors to consider. The sunlight in space is ~7
times brighter than on the surface of the earth,

1.35


...

--
Geoffrey A. Landis
http://www.sff.net/people/geoffrey.landis

Chris Vancil wrote:

You might take a look at Tam Czarnik's

EBULLISM AT 1 MILLION FEET:
Surviving Rapid/Explosive Decompression

http://www.sff.net/people/Geoffrey.Landis/ebullism.html

Would this summary be wrong?
* Humans will with high chances survive up to 1 minute of vacuum
in non-explosive decompression
* If helmets were separately pressurised, or even just capable
of maintaining a (declining) pressure differential for a
short period of time, chnaces of survival of a punture or
tear in the suit would go up considerably.
* Any compartmentalisation will help
* Anybody exposed in a non-trivial way will need rescuing
as even witha separately pressured helmet they will be
losing control of (parts of) body functions fast.

--
Sander

+++ Out of cheese error +++

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Hash: SHA1

I think you're all missing an important point... HEAT. It's danged
cold in shadow (background temp of deep space is ~4K, and in the
sunlight, it's danged hot (Huge amount of unfiltered solar energy)...
I suppose you could cover your suit with a couple of layers of MLI,
though - but that stuff's pretty fragile, & you'd be quick to
overheat in it, because it's too good of an insulator while in a
vacuum (something like 99.5% efficient)

"Ian Stirling" wrote in message
...
James Moughan wrote:
I've been wondering, just what is the minimum protection you can
get away with and still be able to function effectively in a
vacuum?

Say you're breathing pure oxygen at 2psi. That's a partial
pressure of 1/3 below sea-level, which should be adequate
providing you site

Various places use 5PSI pure O2 as a second choice to sea-level
mix. This corresponds quite well to the 4.6 PSI you need to get the
same partial pressure of oxygen at the lung wall (there is water
vapour and CO2 there too).

In the article with message-ID:

posted in april 2002, I posted the results of some sums.
At 1.8PSI you'r groggy and weak, even if acclimitised.
At 2.1PSI, more or less OK.
snip
vascular system can support an internal pressure of 2psi without
any outside help, and so, I'm guessing, can the skin. In that
case, there's no actual need for a pressure suit. You ought to
be able to get away with an oxygen mask covering the eyes, nose
and mouth.
snip
Or am I overlooking something?

Yes.
Fluid will rapidly pool in the limbs causing them to become swolen
and useless.

You need something to provide a pressure in the flesh that's high
enough to squeeze the blood back from the extremeties to the
heart.

The skin usually does this, with the help of the lymphatic system.
However, in space this won't work nearly well enough.

However, do some searching on "skin suit".
Basically, you use a tight elasticated suit to maintain a pressure
over the body, hope the lymphatic system can iron out any minor
inconsistancies, and don't pressurise the suit, only having a
pressurised helmet.
Gloves are a big problem, owing to the complex geometry.
The torso is another problem, leading some to suggest just doing
the limbs, and using a hard torso.

--
http://inquisitor.i.am/ | |
Ian Stirling.
---------------------------+-------------------------+--------------
------------ Two fish in a tank: one says to the other, "you know
how to drive this thing??"

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Sander Vesik wrote:
Chris Vancil wrote:

You might take a look at Tam Czarnik's

EBULLISM AT 1 MILLION FEET:
Surviving Rapid/Explosive Decompression

http://www.sff.net/people/Geoffrey.Landis/ebullism.html

Would this summary be wrong?
* Humans will with high chances survive up to 1 minute of vacuum
in non-explosive decompression

Probably - if promptly resuccitated, breathing may not be spontaneous
after a few tens of seconds.
Explosive decompression doesn't change anything, unless you try to
hold your breath.

* If helmets were separately pressurised, or even just capable
of maintaining a (declining) pressure differential for a
short period of time, chnaces of survival of a punture or
tear in the suit would go up considerably.

If you pressurise the lungs without external pressure on the chest,
there is a very large risk of the lungs popping.
This a bad thing.

* Any compartmentalisation will help
Perhaps.

* Anybody exposed in a non-trivial way will need rescuing
as even witha separately pressured helmet they will be
losing control of (parts of) body functions fast.

Limbs that lose pressure will become non-functional very rapidly.
Probably not immediately fatal though.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
My inner child can beat up your inner child. - Alex Greenbank

Tom Burke wrote:

I think you're all missing an important point... HEAT. It's danged
cold in shadow (background temp of deep space is ~4K, and in the

But you have no conductive or convective cooling.

How cold is space?
Well, assuming the body has an area of 1.5 meters square, and the skin
is at 27C, that's 690W of heat lost. (stephan-boltzman)

Reading from a (too small) table indicates that the equivalent heat loss
happens at a wind-chill of -13C.

In LEO, the earth is a big factor, as it's around 180 degrees of
radiator at a few C.

So that'll be near 450W in LEO.

So, in deep space in sunlight, a naked person loses around 200W (heavy
shivering should make this up), and in LEO, gains around 200W.

sunlight, it's danged hot (Huge amount of unfiltered solar energy)...

Around 1.2 times the maximum on earth, not really very huge.

I suppose you could cover your suit with a couple of layers of MLI,
though - but that stuff's pretty fragile, & you'd be quick to
overheat in it, because it's too good of an insulator while in a
vacuum (something like 99.5% efficient)

snip quoted message incorrectly placed at bottom

Sweating through the suit may well work.
The sunlight is more or less the same as on earth, though the humidity is
always 0%.

In terms of emergency suits.
The body is largely made of water, and if the circulation is working,
it all has to heat or cool by around 3C or so before you have much
danger of actual immediate problems.

Totally insulated from the surroundings, and working hard, you've
still got 20-30 minutes before you pass out.

Even adding in sunlight, it's still well over 10 minutes.

--
http://inquisitor.i.am/ | | Ian Stirling.
---------------------------+-------------------------+--------------------------
He had been eight years upon a project for extracting sunbeams out of cucumbers,
which were to be put in vials hermetically sealed, and let out to warm the air
in raw inclement summers. -- Jonathan Swift, "Gulliver's Travels" (1726)

News Admin wrote:
Sander Vesik wrote:
Chris Vancil wrote:

You might take a look at Tam Czarnik's

EBULLISM AT 1 MILLION FEET:
Surviving Rapid/Explosive Decompression

http://www.sff.net/people/Geoffrey.Landis/ebullism.html

Would this summary be wrong?
* Humans will with high chances survive up to 1 minute of vacuum
in non-explosive decompression

Probably - if promptly resuccitated, breathing may not be spontaneous
after a few tens of seconds.
Explosive decompression doesn't change anything, unless you try to
hold your breath.

* If helmets were separately pressurised, or even just capable
of maintaining a (declining) pressure differential for a
short period of time, chnaces of survival of a punture or
tear in the suit would go up considerably.

If you pressurise the lungs without external pressure on the chest,
there is a very large risk of the lungs popping.
This a bad thing.

Oh. But this would depend on the pressure differential between the chest
and lungs, right? I guess it also depends on what extent a possibly quite
low pressure in the helmet would improve chances of survival over vacuum.


* Any compartmentalisation will help
Perhaps.

* Anybody exposed in a non-trivial way will need rescuing
as even witha separately pressured helmet they will be
losing control of (parts of) body functions fast.

Limbs that lose pressure will become non-functional very rapidly.
Probably not immediately fatal though.


Rescuing in the sense of "won't be able to use that limb to operate
anything" - i imagine constant pain etc could also cause fainiting
and similar well advance of any effects that would cause unconsiousness
or shock (which are other reasons why the person might need rescuing).

--
Sander

+++ Out of cheese error +++

Geoffrey A. Landis wrote:

In k.net Anthony Q.
Bachler wrote:
There are other factors to consider. The sunlight in space is ~7
times brighter than on the surface of the earth,

1.35

You (Anthony) may be thinking of total insolation -- effectively
proportional to the average power a solar cell can generate, and
therefore the number of interest in comparing space power satellites to
ground-based solar power -- which on Earth includes the decrease in
sunlight flux away from noon (due to both geometry and increased
atmospheric absorption) and of course the lack of sunlight at night.
Geoff can doubtless cite exact numbers, but a factor of 4 to 5 is
reasonable; a factor of 7 is a little high but not unreasonable for,
say, wintertime at 40 deg. latitude vs. high Earth orbit. Not the same
as brightness.

--
Jordin Kare

"Point and click" means you're out of ammo.

Hmm, perhaps you are right. The figure 7 stuck in my head from somewhere,
which was more likely than not a space based powersat discussion ( Im an EE
by trade ). The remainder of my post holds I do believe.

--
"Yea, all israel have transgressed thy law, even by departing, that they
might not obey thy voice; therefore the curse is poured upon us, and the
oath that is written in the law of Moses the servant of God, because we have
sinned against him." Daniel 9-11