Well, if you're talking simulating being in space...all things
considered, I think I'd rather ride a rocket. If you're talking sense-
dep only...all things considered, 800 pounds of Epson salt in warm
water sounds a lot safer...
jm
ps -- Sounds like moderate exertion would prove fatal.
On 5 Jul 2001, at 20:26, Spike Jones wrote:
> I am endebted to Anders Sandberg for this idea.
>
> The air we breathe consists of about 0.2 atmospheres
> of oxygen and about 0.8 atmospheres nitrogen. Divers
> have shown that helium can be substituted for the nitrogen,
> since the body does not use either substance. Helium
> actually works better for high pressure applications, since it is
> a noble gas, and so does not react with or dissolve in the
> bloodstream like nitrogen will do under sufficient pressure.
> In a diving bell, oxygen can be held at .2 atmospheres and
> helium added with no apparent harm or discomfort to the
> divers.
>
> The noble gas xenon is chemically similar to helium,
> except for being nearly 33 times denser. If a person
> were to be placed in a pressure chamber with oxygen held at
> 0.2 atmospheres, then xenon added until the total pressure came
> up to about 190 atmospheres, the density of the gas mixture
> in the chamber would be about equal to that of water. The
> person would then float. It would simulate weightlessness
> better than being in water, since the xenonaut could breathe the
> medium in which she was floating.
>
> The partial pressure of oxygen would need to be increased
> somewhat to counteract the tendency of the oxygen to
> float to the top, however there is no reason to doubt that
> humans could swim in xenon. The experience would not
> be exactly the same as floating in your living room however,
> for the pitch of the voice varies as the inverse square root
> of the density of the medium. The xenon swimmer's voice
> would be lowered by nearly 4 octaves, causing her to talk
> like Lurch the butler.
>
> It would take no extraordinary engineering of pressure vessels
> to accommodate 190 atmospheres. In fact even a relatively
> thin walled container would do fine, if one could arrange to lower
> it into the sea as the pressure is raised. Alternately, the chamber
> could be placed at the bottom of a mile-deep shaft and water could
> be allowed to flow in as the pressure is raised, then drained
> as the pressure is lowered. Even if the pressure needed to be
> dropped quickly, this should not present a problem, since it has
> been pointed out that the solubility of xenon is negligible. The worst
> possible effect would be the expanding xenon would escape from
> the bodily orifices into which it has been forced during the
> pressurization, perhaps creating embarrassing noises.
>
> The one killer app for weightlessness that eeeeveryone wants
> to try might not work out either, since one likely could not
> breathe fast enough. The dense column of xenon would resist
> changing direction quickly, so the participants could scarcely
> get their breathing rate much above 1 Hz, insuffient for this
> kind of activity. Then there's the problem of sounding like
> Jabba the Hut and Mrs. Hut on their honeymoon, which might
> in itself spoil the mood. Other than that, one could put together
> a really cool sensory deprivation chamber. spike
>
>
John Marlow
This archive was generated by hypermail 2b30 : Fri Oct 12 2001 - 14:39:42 MDT