Who hasn't seen a science station on the bottom of the ocean? The problem with these things is that the super thick lexan holding out the ocean always breaks, and in it comes (along with supersharks, trench monsters, aliens, etc). The reason deep-sea habitats are necessary is that without something to hold it in, the gas we breathe would bubble away.

The solution: use a breathing mixture heavy enough that it will not float. Xenon would work for this, I think. Physics is not my strong suit, so feel free to burst my bubble, [World]. Helium-oxygen mixtures are already used by deep divers, and xenon is equally safe to breathe.

With every doubling of pressure, the weight of a given volume of gas doubles. The weight of a volume of water does not change with pressure. My math: 1 atm increase with 10 meters depth

1 liter H2O = 100 gm 22.4 liters water = 2240 gm 22.4 liters xenon at 1 atm = 52 gm 52x = 2240 x = 2240/52 = 43 atm or 430 meters

So I figure that at 431 meters depth, a bubble of xenon will sink. Therefore a permanent subsea habitat could be made below 431 meters just by pumping a hole in the sea floor full of xenon. The xenon will not bubble out. You could access it by walking down some stairs. You might want to put a tented tarp over the top, just to keep dead fish from falling in to your cafeteria. You would need CO2 scrubbers, and you would need to add a little oxygen, but at super high pressure it would be about the same amount as vermouth in a martini.

A corollary to this is that there might be big pockets of xenon that have accumulated under the ocean floor, lighter gasses having bubbled away over the eons. Such a pocket could be used as a premade habitat. The pockets might also have a lot of radon in them too, so best to wear your lead undies.
-- bungston, May 31 2004

Xenon http://www.boc.com/...s/pdf/msds/G085.pdf
A great game for the Atari, and a charming noble gas. [neilp, Oct 04 2004, last modified Oct 06 2004]

Liquid Breathing Mixture http://www.chm.bris...iquid_breathing.htm
[ldischler, Oct 04 2004, last modified Oct 06 2004]

Xenon makes you high http://www.techdive...tic_gases.shtml#4.1
I did not know xenon was an even better narcotic than nitrogen. Oh well. [bungston, Dec 12 2005]

spin polarized noble gases are like robot drugs plus remote viewing http://www.lbl.gov/...-detection-MRI.html
Saxena describes the successful first attempt to prove the remote-detection principle: "We were able to demonstrate the rather fantastic notion that a picture of a sample cell could be obtained by saturating it with xenon gas in one spectrometer and then moving the gas -- by as much as 15 feet -- to another spectrometer for signal detection. Despite the long separation and travel time, the xenon gas faithfully remembered the shape of the sample [beanangel, May 26 2009]

Athletes breathe xenon http://news.discove...ton-next-140902.htm
50% xenon! And running around! [bungston, Sep 02 2014]

Xenon anaesthesia http://en.wikipedia...ki/Xenon#Anesthesia
Proven technology [8th of 7, Sep 02 2014]

//and xenon is equally safe to breathe// - I'm not so sure.

(edit)
[neilp] flicks through google - OK.. ignore me. I was never any good at chemistry..
-- neilp, May 31 2004


Here is my calculation:
Molar mass of Xe: 131g
Molar volume of ideal gases 22.4l at 1 atm
Density of Xe at 1 atm: 131g/22.4l = 5.85g/l
Pressure required to get density up to 1kg/l: 1000g/5.85g*1atm = 171atm
Equivalent depth: 171atm/(1atm/10m)=1710m

Actual depth may be lower because Xe is not an ideal gas and density rises faster with pressure, but 430m seems low to me.

It is still a good idea, but some testing will be required. I have seen fans blow up because they had to fan SF6 (mass about 150) instead of air. Human lungs could have similar problems when they have to ventilate 1kg/l instead of 1g/l.

[neilp] link? I have never heard about Xenon itself being toxic. It just makes you talk funny.
-- kbecker, May 31 2004


As was the case with my income taxes, I made 2 math mistakes which partially counteracted each other. I forgot Xe exists as Xe2 and so a volume of xenon would weigh double what I thought. Also I thought a liter of water weighed 100 gm, not 1000. I even looked that up.

As regards breathing dense stuff, those perfluorinated fluids must be pretty dense and people seem ok with them at 1 atm. Divers breathe stuff substatially denser that 1 atm air and get away with it. But I agree, maybe best to send the canaries in first.

Also, I take back what I wrote about the CO2 scrubbers. Since you would be in a xenon bubble, the CO2 would equilibrate with the ocean water outside and take care of itself. Of course the O2 would also so you would need to keep adding that.
-- bungston, May 31 2004


A couple of points: There's no stable Xe2; and Xe is too soluble in water for any deposits to build up. (Otherwise, pools of Xe on the ocean floor would be a goldmine--and actually, it's a lot more valuable than gold.)
-- ldischler, May 31 2004


Is it actually possible to survive at 171atm unaided anyway? Would the bubble also dissolve into the water?
-- chud, May 31 2004


/would the bubble also dissolve?/ Probably it would. I did not know xenon was water soluble. So the whole thing would need to be wrapped with a plastic film. But if the film got punctured in a moment of unbridled passion / shark attack, the bubble would not immediately escape.
-- bungston, May 31 2004


Hmm..

If the bubble is heavier than water..

would we float in it?
-- yamahito, May 31 2004


If your math is right, I say good for you.

I like it, though the bubble dissolving would be bad.

Everyone, sharks wouldn't puncture it because they can't live at that depth.

Add a membrane.

yamahito, if it were denser than the water, of course we would float in it. We float in water, right?
-- DesertFox, May 31 2004


...
-- yamahito, May 31 2004


:)
-- DesertFox, May 31 2004


ok, ok, the floating in it would make things strange for the bubble dwellers. Actually it is a little hard for me to imagine how it would be in the bubble. A pretty weird concept. Maybe they would just have to wear weight belts everywhere.
-- bungston, May 31 2004


So install stirrers.
-- DesertFox, May 31 2004


How about that CFC that holds oxygen and have it encased in a plastic bubble. +
-- sartep, Jun 01 2004


Fun Fact: there are regions at the bottom of the ocean where the pressure is so great that liquid CO2 remains in liquid form.
-- 5th Earth, Jun 21 2004


I wish *I* had a fun fact. But I don't.

Croissant for idea of what amounts to a habitat without any niceties like hard surfaces. I like it.
-- shapu, Jun 21 2004


You definitely cannot survive at 171 atm. However, the idea of xenon-oxygen breathing mixture could have nifty applications. So instead of a dead fishie falling into your habitat, I'll drop a croissant on you. +
-- evilmathgenius, Jun 21 2004


Dreaky

I think

possibly

anyway There are noble gases that when they have their spins polarized actually stay polarized for like 15 minutes NMR patients breathe these spin polarized gases as contrast nhancers

Rudy Rucker wrote about robots that had their CPU areas filled with spin polarized noble gases as a way of creating all encompassing jungian synchronicity that the robots could appreciate This gas known as dreak is kind of like AI LSD

the acual berkeley lab version is that you can do a gas MRI then pipe (this is truly amazing, think of the fluid dynamics) the gas 7 meters away n still see what it was you did an MRI of

thus your habitat could also feature drugged robots if you like

If these are Berkeley Robots they could actually have shared analog vision with higher than digital bandwidth
-- beanangel, May 26 2009


//You definitely cannot survive at 171 atm. However, the idea of xenon-oxygen breathing mixture could have nifty applications. So instead of a dead fishie falling into your habitat, I'll drop a croissant on you. +//

[ignorant] - Why, may I ask, not? Just what is it about our physiology that stops us from surviving at depth? [/I]

-Are we really sure Xe exists as Xe2 in any significant proportions-? I doubt it...

-By this same logic, why can't we use say an Argon-Oxygen atmosphere, at 40g/mol should be stable at ~5600m depth....
-- Custardguts, May 27 2009


dreak!

that is very trippy, Beanangel.
-- bungston, May 27 2009


The first problem I see with humans at pressures like that, is O2 poisoning. As you have already established, pressure is inversely proportional to volume. Oxygen is a toxic gas at 1.6 bar and up. At a greater depth, more gas can and will fit into the same volume. Even if you are still breathing the proper percentage of Oxygen, you are still exposing the alveoli in your lungs to more oxygen per unit of area. If I recall correctly, deep dive gas mixtures do not contain as much O2 as what we breath at 1atm. It is replaced with a less active, and less blood soluble gas.

Also, at that pressure, protein synthesis and enzymatic actions in the body are not the same. This may or may not cause a problem because the phenomenon is a fairly recent discovery.

As for Xenon.... Bad. An environment like that would give rise to oxygen containing xenon compounds. These are usually toxic or explosive. (XeO3 and XeO4)
-- threeeyedwilly, May 01 2010


I don't think there would be xenon oxides because they take a lot of energy to make and they don't just form from xenon and oxygen floating around together without any catalyst, ionisation or something. The problem would be xenon dissolving in neuronal plasma membranes causing narcosis, which happens just as much with most noble gases as it would with any other gas. They don't have to react to do that. Helium is, i think, the safest gas in this respect.

Also, xenon is very expensive.

Hello, incidentally.
-- nineteenthly, May 01 2010



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