survial in a vacuum
adsum
hi - what would happen to an astronaut if he/she encountered rapid
decompression say through the sudden breaching of a spacecraft or loss of
a helmet with full head exposure to outer space? would the effect be a
gradual swelling due to bodily gas expansion or would it be quicker, and
more explosive? would the eardrums rupture? what would be the effects on
the brain? lungs? internal organs? can someone point me to a reputable
website that discusses this?
Bryan McFadden
Ipse Dixit Films
http://www.ipsedixit.com
--
Bryan McFadden
Ipse Dixit Films
http://www.ipsedixit.com
Henry Spencer
In article <Pine.SUN.3.96.98062...@eskimo.com>,
adsum <ad...@eskimo.com> wrote:
>hi - what would happen to an astronaut if he/she encountered rapid
>decompression say through the sudden breaching of a spacecraft or loss of
>a helmet with full head exposure to outer space? would the effect be a
>gradual swelling due to bodily gas expansion or would it be quicker, and
Neither. Hollywood notwithstanding, exposure to vacuum does not
immediately cause any of these symptoms. The Soyuz 11 crew was killed by
decompression early in their reentry sequence, their bodies spent at least
several minutes in vacuum, and there was so little obvious damage that the
recovery crew reportedly started CPR. The decompression in that case was
gradual, but the only problem added by more rapid decompression is the
possibility of sudden pressure differences leading to eardrum rupture or
lung damage.
What kills someone exposed to vacuum is simply lack of oxygen. Everything
else happens much more slowly.
This used to be in the sci.space.* FAQ, and on one of the NASA web sites
as well. Both versions were more or less written by me, and I've long
meant to do an updated version, but haven't yet found time.
--
Being the last man on the Moon is a | Henry Spencer he...@spsystems.net
very dubious honor. -- Gene Cernan | (aka he...@zoo.toronto.edu)
Ian Stirling
adsum <ad...@eskimo.com> wrote:
: hi - what would happen to an astronaut if he/she encountered rapid
: decompression say through the sudden breaching of a spacecraft or loss of
: a helmet with full head exposure to outer space? would the effect be a
: gradual swelling due to bodily gas expansion or would it be quicker, and
: more explosive? would the eardrums rupture? what would be the effects on
: the brain? lungs? internal organs? can someone point me to a reputable
: website that discusses this?
Use dejanews, search on
sci.space* man in space
In short, if you hold your breath, your lungs explode, if you don't, then
the oxygen in your blood boils out of your lungs, leaving you unconsious
in around 10 seconds (the oxygen leaves, unused, rather than being converted
to CO2, as when you hold your breath.).
After around 60s, brain damage probably starts to set in, and after
5 mins, you are likely dead. (due to there hardly being any oxygen
in the body, far less for example than someone drowning)
After that, you probably end up cooling/bloating, and eventually
end up a freeze-dried corpse.
--
See http://www.mauve.demon.co.uk/ |Linux PDA, cheap electronics/PC bits sale.
See_header,_for_UCE_policy___________|_____________________________Ian_Stirling.
'Terror is the most effective political instrument.... I shall spread terror by
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The important thing is the sudden shock of an overwhelming fear of death.'
Adolf Hitler.
Geoffrey A. Landis
This is a topic that comes up frequently on sci.space and
rec.arts.sf.science.
The quick answers to these questions are: Clarke got it about right in
2001. You would survive about a ninety seconds, you wouldn't explode,
you would remain conscious for about ten seconds.
The best data I have comes from _Bioastronautics Data Book_, Second
edition, NASA SP-3006, edited by James F. Parker and Vita R. West, 1973,
in the article "Chapter 1: Barometric Pressure," by Charles E. Billings.
This chapter discusses animal studies of decompression to vacuum. It
does not mention any human studies.
page 5, (following a general discussion of low pressures and ebullism):
"Some degree of consciousness will probably be retained for 9 to 11
seconds (see chapter 2 under Hypoxia). In rapid sequence thereafter,
paralysis will be followed by generalized convulsions and paralysis once
again. During this time, water vapor will form rapidly in the soft
tissues and somewhat less rapidly in the venous blood. This evolution of
water vapor will cause marked swelling of the body to perhaps twice its
normal volume unless it is restrained by a pressure suit. (It has been
demonstrated that a properly fitted elastic garment can entirely prevent
ebullism at pressures as low as 15 mm Hg absolute [Webb, 1969, 1970].)
Heart rate may rise initially, but will fall rapidly thereafter.
Arterial blood pressure will also fall over a period of 30 to 60 seconds,
while venous pressure rises due to distention of the venous system by
gas and vapor. Venous pressure will meet or exceed arterial pressure
within one minute. There will be virtually no effective circulation of
blood. After an initial rush of gas from the lungs during decompression,
gas and water vapor will continue to flow outward through the airways.
This continual evaporation of water will cool the mouth and nose to
near-freezing temperatures; the remainder of the body will also become
cooled, but more slowly.
"Cook and Bancroft (1966) reported occasional deaths of animals due to
fibrillation of the heart during the first minute of exposure to near
vacuum conditions. Ordinarily, however, survival was the rule if
recompression occurred within about 90 seconds. ... Once heart action
ceased, death was inevitable, despite attempts at resuscitation....
[on recompression] Breathing usually began spontaneously... Neurological
problems, including blindness and other defects in vision, were common
after exposures (see problems due to evolved gas), but usually
disappeared fairly rapidly.
"It is very unlikely that a human suddenly exposed to a vacuum would have
more than 5 to 10 seconds to help himself. If immediate help is at hand,
although one"s appearance and condition will be grave, it is reasonable
to assume that recompression to a tolerable pressure (200 mm Hg, 3.8
psia) within 60 to 90 seconds could result in survival, and possibly in
rather rapid recovery."
Henry Spencer suggests the book by Arnauld E. Nicogossian, Carolyn L.
Huntoon and Sam L. Pool _Space Physiology and Medicine_, 2nd Edition, Lea
and Febiger, Philadelphia 1989.
Another useful reference is
"Rapid (Explosive) Decompression Emergencies in Pressure-Suited
Subjects", by Emanuel M. Roth, NASA CR-1223, circa 1968. Its focus is on
decompression, rather than vacuum exposure per se, but it still has a lot
of good info.
There are three cases of human exposure to vacuum worth noting. In 1966
a technician at NASA Houston was decompressed to vacuum in a space-suit
test accident. This case is discussed by Roth in the reference above.
He lost consciousness in 12-15 seconds. When pressure was restored after
about 30 seconds of exposure, he regained consciousness, with no apparent
injury sustained.
In 1960, in a balloon-jump, another vacuum exposure for longer term but
not for a whole-body exposure occurred:
"The experiment of exposing an unpressurized hand to near vacuum for a
significant time while the pilot went about his business occurred in real
life on Aug. 16, 1960. Joe Kittinger, during his ascent to 102,800 ft
(19.5 miles) in an open gondola, lost pressurization of his right hand.
He decided to continue the mission, and the hand became painful and
useless as you would expect. However, once back to lower altitudes
following his record-breaking parachute jump, the hand returned to
normal."
[quoting from Leonard Gordon, _Aviation Week_, February 13th 1996.
Finally, posting to sci.space, Gregory Bennett discussed an actual space
incident:
"Incidentally, we have had one experience with a suit puncture on the
Shuttle flights. On STS-37, during one of my flight experiments, the
palm restraint in one of the astronaut's gloves came loose and migrated
until it punched a hole in the pressure bladder between his thumb and
forefinger. It was not explosive decompression, just a little 1/8 inch
hole, but it was exciting down here in the swamp because it was the first
injury we've ever head from a suit incident. Amazingly, the astronaut in
question didn't even know the puncture had occured; he was so hopped on
adrenalin it wasn't until after he got back in that he even noticed there
was a painful red mark on his hand. He figured his glove was chafing and
didn't worry about it.... What happened: when the metal bar punctured
the glove, the skin of the astronaut's hand partially sealed the opening.
He bled into space, and at the same time his coagulating blood sealed
the opening enough that the bar was retained inside the hole."
More details can be found in the sci.space FAQ:
http://www.cis.ohio-state.edu/hypertext/faq/usenet/space/top.html
and at a site at NASA Johnson:
http://medlib.jsc.nasa.gov/intro/vacuum.html
(which quotes liberally [and without credit] from the old discussiona on
sci.space)
________
Geoffrey A. Landis
Ohio Aerospace institute at NASA Lewis Research Center
http://www.sff.net/people/Geoffrey.Landis/
Cfrjlr
Henry and Geoff,
Excellent postings as ever.
Geoff's posting is more detailed than the FAQ with more recent info, could
perhaps be added in ?
Do we know who the STS-37 astornaut was ?
Charles F. Radley
http://members.aol.com/cfrjlr/
Henry Spencer
Nicholas Landau
he...@spsystems.net (Henry Spencer) writes:
>In article <Pine.SUN.3.96.98062...@eskimo.com>,
>adsum <ad...@eskimo.com> wrote:
>>hi - what would happen to an astronaut if he/she encountered rapid
>>decompression say through the sudden breaching of a spacecraft or loss of
>>a helmet with full head exposure to outer space? would the effect be a
>>gradual swelling due to bodily gas expansion or would it be quicker, and
>>more explosive? ...
>What kills someone exposed to vacuum is simply lack of oxygen. Everything
>else happens much more slowly.
I am not an authority on this issue, but...
When people are exposed to lesser degrees of decompression, they are
known to suffer "the bends." This is a frequently fatal condition
caused by the formation of nitrogen (N2) bubbles forming in the
blood. I would expect he same thing would happen if the cause of
decompression were loss of a spacecraft's atmosphere.
Divers suffer the bends if they rise too quickly. They sometimes also
rupture their eardrums. My family's poodle lost her hearing when an
airplane's cargo compartment lost pressure (or so the vet believes.)
In the case of the Suez mission, pressure may have dropped too slowly
for such symptoms to appear.
Ian Stirling
Nicholas Landau <nla...@eden.rutgers.edu> wrote:
: he...@spsystems.net (Henry Spencer) writes:
:>In article <Pine.SUN.3.96.98062...@eskimo.com>,
:>adsum <ad...@eskimo.com> wrote:
:>>hi - what would happen to an astronaut if he/she encountered rapid
:>>decompression say through the sudden breaching of a spacecraft or loss of
:>>a helmet with full head exposure to outer space? would the effect be a
:>>gradual swelling due to bodily gas expansion or would it be quicker, and
:>>more explosive? ...
:>What kills someone exposed to vacuum is simply lack of oxygen. Everything
:>else happens much more slowly.
: I am not an authority on this issue, but...
: When people are exposed to lesser degrees of decompression, they are
: known to suffer "the bends." This is a frequently fatal condition
: caused by the formation of nitrogen (N2) bubbles forming in the
: blood. I would expect he same thing would happen if the cause of
: decompression were loss of a spacecraft's atmosphere.
Not always lesser degrees, coming from 2-1 Atm is the same bendswise.
Anyway, yes the bends would be a problem if the time taken to die from other
causes wasn't shorter than the time for the bends to ba a major problem.
--
See http://www.mauve.demon.co.uk/ |Linux PDA, cheap electronics/PC bits sale.
See_header,_for_UCE_policy___________|_____________________________Ian_Stirling.
The fight between good and evil, an epic battle. Darth vader and Luke,
suddenly in the middle of the fight, Darth pulls Luke to him, and whispers
"I know what you'r getting for christmas!" Luke exclaims "But how ??!?"
"It's true Luke, I know what you'r getting for christmas" Luke tries to ignore
this, but wrenches himself free, yelling "How could you know this?",
Vader replies "I felt your presents"
JP Camplin
On Sat, 4 Jul 1998, Ian Stirling wrote:
> : When people are exposed to lesser degrees of decompression, they are
> : known to suffer "the bends." This is a frequently fatal condition
> : caused by the formation of nitrogen (N2) bubbles forming in the
> : blood. I would expect he same thing would happen if the cause of
> : decompression were loss of a spacecraft's atmosphere.
>
> Not always lesser degrees, coming from 2-1 Atm is the same bendswise.
> Anyway, yes the bends would be a problem if the time taken to die from other
> causes wasn't shorter than the time for the bends to ba a major problem.
On risk of being considered pedantic I think that you might find that
going from 2 to 1 atm is vastly different from going from 1atm to vac.
Talk to any diver and they will tell you all about Boyles Law (or college
scientist for that matter). The change in pressure from 2-1 is
"fractionally" half that of 1atm to vac and as PV=nRT you might find that
effects due to increase in gas volume or out-gassing of fluids in the body
are massively different.
But I'm sure you knew all that....I just couldn't resist.
ttfn
John
Henry Spencer
In article <6ngs2k$2...@er7.rutgers.edu>,
Nicholas Landau <nla...@eden.rutgers.edu> wrote:
>>What kills someone exposed to vacuum is simply lack of oxygen. Everything
>>else happens much more slowly.
>
>known to suffer "the bends." This is a frequently fatal condition
>caused by the formation of nitrogen (N2) bubbles forming in the
>blood. I would expect he same thing would happen if the cause of
>decompression were loss of a spacecraft's atmosphere.
Yes, but again this comes under the heading of "everything else happens
much more slowly". Lack of oxygen will knock you out within 15-20s and
kill you within a minute or so (much more quickly than on Earth, because
there is no air in your lungs and in fact you're *losing* oxygen from the
blood through the lungs). The most the bends will do during that time is
to add some discomfort. The bubbles take time to form and coalesce.
>In the case of the Suez mission, pressure may have dropped too slowly
>for such symptoms to appear.
Uh, no, not by orders of magnitude. At the very low (by diving standards)
pressures involved, bends-free loss of pressure would take hours.
Bill Bonde
>
> In article <6ngs2k$2...@er7.rutgers.edu>,
> Nicholas Landau <nla...@eden.rutgers.edu> wrote:
> >>What kills someone exposed to vacuum is simply lack of oxygen. Everything
> >>else happens much more slowly.
> >
> >When people are exposed to lesser degrees of decompression, they are
> >known to suffer "the bends." This is a frequently fatal condition
> >caused by the formation of nitrogen (N2) bubbles forming in the
> >blood. I would expect he same thing would happen if the cause of
> >decompression were loss of a spacecraft's atmosphere.
>
> Yes, but again this comes under the heading of "everything else happens
> much more slowly". Lack of oxygen will knock you out within 15-20s and
> kill you within a minute or so (much more quickly than on Earth, because
> there is no air in your lungs and in fact you're *losing* oxygen from the
> blood through the lungs). The most the bends will do during that time is
> to add some discomfort. The bubbles take time to form and coalesce.
>
So I'm watching the James Bond movie _Tomorrow Never Dies_ and Bond does
a high altitude jump with oxygen and the head first dive and all and
then slows up at the last minute, hits his chute, drops his chute in the
air at about ten feet or so (seemed like he was in the chute for about
15 seconds at the most) and then went right into the water and switched
to scuba and went directly down to the ship at about 30 feet (a guess)
never surfacing. That was really cool but then both he and a woman must
leave their air tanks behind to escape out the torpedo tubes of the ship
and then on ONE breath they swim out and directly and quickly surface.
Shouldn't the bends have been an issue?
Thomas Moore
>
> So I'm watching the James Bond movie _Tomorrow Never Dies_ and Bond does
> a high altitude jump with oxygen and the head first dive and all and
> then slows up at the last minute, hits his chute, drops his chute in the
> air at about ten feet or so (seemed like he was in the chute for about
> 15 seconds at the most) and then went right into the water and switched
> to scuba and went directly down to the ship at about 30 feet (a guess)
> never surfacing. That was really cool but then both he and a woman must
> leave their air tanks behind to escape out the torpedo tubes of the ship
> and then on ONE breath they swim out and directly and quickly surface.
> Shouldn't the bends have been an issue?
Nah... Bond would never get anything so uncool as the bends..... Q has
outfitted him with a blood pressure powered nitrogen control implant.
The only bends Bond ever gets is after the mission while debriefing the
heroine.
Tom Moore
---------
My opinions and statements are my own and do not represent those of my
employer.
--
Definition of loop: See Definition of loop
Joshua Gigantino
> So I'm watching the James Bond movie _Tomorrow Never Dies_ and Bond does
> a high altitude jump with oxygen and the head first dive and all and
> then slows up at the last minute, hits his chute, drops his chute in the
> air at about ten feet or so (seemed like he was in the chute for about
> 15 seconds at the most) and then went right into the water and switched
> to scuba and went directly down to the ship at about 30 feet (a guess)
> never surfacing. That was really cool but then both he and a woman must
> leave their air tanks behind to escape out the torpedo tubes of the ship
> and then on ONE breath they swim out and directly and quickly surface.
> Shouldn't the bends have been an issue?
I wouldn't think that the bends would have been a problem, as it didn't
seem like they were under water long enough, in deep enough water. At
thirty feet, it takes something like 12 hours for enough nitrogen to build
up to need decompressing. Don't quote me on that, it's been a long long
time since I dove. I have a chart someplace at home that gives
decompression times, if you are interested.
Even if they were in 60-100 feet of water, they wouldn't have had time to
absorb enough nitrogen to need decompressing.
As far as the 'one breath' thing, I've never had to surface without tanks,
but my stepfather has, and he says that even from 100 feet, one breath is
enough, since the air you breath @100 is compressed to over three
atmospheres. When surfacing like that, he told me that you just 'whistle'
at a steady pace to vent the air fast enough without rupturing a lung.
J05H
Jason Goodman
>
> So I'm watching the James Bond movie _Tomorrow Never Dies_ and Bond does
> a high altitude jump with oxygen and the head first dive and all and
> then slows up at the last minute, hits his chute, drops his chute in the
> air at about ten feet or so (seemed like he was in the chute for about
> 15 seconds at the most) and then went right into the water and switched
> to scuba and went directly down to the ship at about 30 feet (a guess)
> never surfacing. That was really cool but then both he and a woman must
> leave their air tanks behind to escape out the torpedo tubes of the ship
> and then on ONE breath they swim out and directly and quickly surface.
> Shouldn't the bends have been an issue?
First, the bends are not an issue when pressure is *increasing*, only
when decreasing. Now, if Bond had immediately gone back on the
airplane, there might have been a problem. As it was, being in an
airplane beforehand would actually *decrease* the dissolved N2 in
his blood.
IIRC, You can safely make a "free ascent" the way Bond did from a depth
of 30 feet after having stayed down for as long as 45 minutes, maybe
even an hour, without getting the bends. I don't have my decompression
tables handy.
The tricky bit is that you have to constantly exhale as you ascend,
because the air expands in your chest. It's possible to dive down as
deep as 80-100 feet for a few minutes, and swim to the surface without
scuba equipment, and have your lungs be as full beforehand as
afterward.
Josh
They are very dangerous (acceleration trauma?) and usually the domain of
those very burly 'were going to sneak in and kill with surgical precision'
types. I think the usual injury is from the snap when the chute catches.
Doug Jones
>
> High ALtitude Low Opening (HALO) parachute drops are a military
> reality. They are very dangerous (acceleration trauma?) and usually
> the domain of those very burly 'were going to sneak in and kill with
> surgical precision' types. I think the usual injury is from the snap
> when the chute catches.
Nope- the usual injury is massive blunt trauma when somebody tries to
open too low. Opening shock on a main parachute is typically under 4
gees, limited by deployment devices such as a bag, lines stows, and
slider. (Heck, I used to rest my head on my reserve chute on my pig rig
PC and watch the canopy deploy. Quite a show...)
Even reserve chutes, intended to open qucikly and stop you *now*, rarely
and only momentarily go over ten gees. It does tend to leave you a
little stunned (and happy :) ...but opening shock is not injurious.
--
Doug Jones
"Ya keep pulling handles till your goggles fill with blood."
Bill Bonde
}
} High ALtitude Low Opening (HALO) parachute drops are a military reality.
} They are very dangerous (acceleration trauma?) and usually the domain of
} those very burly 'were going to sneak in and kill with surgical precision'
} types. I think the usual injury is from the snap when the chute catches.
In the Bond film, I was further wondering how he got out of the plane.
If he was really jumping at HIGH altitude, you'd think he couldn't just
jump off the back of the plane with everyone just standing there without
O2 themselves.