Surviving in Space Without a Spacesuit

Geoffrey writes "The recent movie Sunshine features a scene (echoing the famous scene in 2001: a Space Odyssey) in which two astronauts have to cross from one ship to another without spacesuits. But, can you survive in space without a spacesuit? Morgan Smith, writing in Slate, asks whether this is realistic, and concludes: "Yes, for a very short time.""

SG-1 had a similar scene

[smooth wombat (796938)]

In the episode where they were experimenting with a captured ship, T'lk and O'Neill were flung out to Jupiter and left without a way to get home.

Carter's dad, herself and Daniel are able to rescue them but the two have to eject from their ship and float in space for a few seconds before the ring transport can be used.

I do believe that the two had a spacesuit of some type on but not one that was designed for space. More of a general cover suit.

Re:SG-1 had a similar scene

[ucblockhead (63650)]

Lots of SF shows have done it. Battlestar Galactica did it as well.

Re:SG-1 had a similar scene

[Ucklak (755284)]

I liked how Outland [imdb.com] dealt with the subject; just have the guys explode making a mess in their spacesuit.
Can you imagine being the next guy to use that suit?

"Uh, sorry but Jeff thought that tarantulas were crawling in his suit so he pulled his air line and exploded. We cleaned it the best we could."

Duct tape

[EmbeddedJanitor (597831)]

Lots. Wrap yourself up. Can't explode then.

Couple of rolls sounds like a reasonable makeshift pressure suit.

Re:SG-1 had a similar scene

[profplump (309017)]

I'm with you on the exploding -- if you're caught in space you want to do everything possible to reduce your internal pressure.

But it's not that cold in space. There's not a lot of ambient heat, but there's not a lot of conduction or convection either -- you only lose heat as fast as you radiate. So on the timescale of "holding your breath" the temperature of space is not a significant factor. Likewise the radiation you'd absorb over 60 seconds is likely not a large factor, unless you're particularly close to the source (I don't recall the episode, so I can't comment on their depiction of distance from the star(s)).

Re:SG-1 had a similar scene

[ajs (35943)]

Other useful references:

• Human Exposure to Vacuum, Geoffrey A. Landis [sff.net]
  
• Human Body in a Vacuum, NASA's Ask an Astrophysicist [nasa.gov]
  
• Effects of unprotected exposure to space on Wikipedia [wikipedia.org]
  

Re:SG-1 had a similar scene

[rev063 (591509)]

And if you want some insight into the effects of truly extreme pressure changes on the human body (next to which the vacuum of space is peanuts) I recommend reading about the Byford Dolphin diving bell accident [wikipedia.org]. Not for the squeamish.

Re:SG-1 had a similar scene

[orzetto (545509)]

And the best quote from that episode was seconds before that, when Carter asked whether it was possible to transport them directly from the inside of the fighter:

Carter Dad, can you beam them up?

Jacob/Selmak Who am I, Scotty?

Re:SG-1 had a similar scene

[Mr.Fork (633378)]

Didn't Chief and his wife (Cally?) have to go into hyperbaric chambers? I think that is the most accurate portrayal of recovery from space exposure. Didn't Outlander as well with Sean O'Connery deal with this too? I think the guy exploded from the inside out from rapid decompression - but I think that could of been a little Hollywoodish.

I think that the injuries the dude form Event Horizon also were pretty real too - his eyes were damaged, frost, and the bubbling of gas from his blood "the bends".

Re:SG-1 had a similar scene

[evanbd (210358)]

Your lungs can't contain the pressure if you try to hold your breath. And you can do a good enough job trying to destroy your lungs. I don't think you'd exactly explode, though.

Exploding from decompression

[rev063 (591509)]

I think the guy exploded from the inside out from rapid decompression - but I think that could of been a little Hollywoodish.

I used to think of the human body exploding due to decompression being pure Hollywood, too, until I read this:

Subsequent investigation by forensic pathologists determined that diver D4, being exposed to the highest pressure gradient, violently exploded due to the rapid and massive expansion of internal gases. All of his thoracic and abdominal organs, and even his thoracic spine were ejected, as were all of his limbs. Simultaneously, his remains were expelled with force through the narrow trunk opening left by the jammed chamber door, less than 60 centimeters (24 inches) in diameter. Fragments of his body were found scattered about the rig. One part was even found lying on the rig's derrick, 10 meters directly above the chambers.

Now, this was a 6atm almost instantaneous decompression. Jumping into space would be at most a 1atm differential, so nothing like this is likely to happen. Gruesomely cool, though.

Imagine drowning if you couldn't hold your breath

[elrous0 (869638)]

This has been dealt with [sff.net] many times before and there is even a case of a NASA tech who was exposed to vacuum in 1966. He lost consciousness in about 12-14 seconds and was regained consciousness without injury after they restored pressure at about 30 seconds.

The conscensus seems to be consciousness for 10-15 seconds, no serious injury for 60 seconds to 2 minutes.

Re:Imagine drowning if you couldn't hold your brea

[Raul654 (453029)]

After he came to, they asked the tech what the last thing he remembered was. He told them the last thing he remembered before blacking out was the saliva on his tongue boiling away (due to the extremely low pressure lowering the boiling point of the saliva)

A Serious case of YMMV

[wsanders (114993)]

A long time ago I took a pressure chamber ride at NASA to 27,000 ft. I lasted about 15 sec until uselessness (the crew master didn't let us go all the way to LOC), and 27,000 is not a particularly extreme altitude. Generally, 50,000 ft is considered the altitude at which the partial pressure of oxygen is no longer adequate to maintain consciousness. You can survive up to about 80,000 if you "pressure breathe", i.e have a rig that forces oxygen into your lungs at a lightly higher pressure than ambient, but not enough to bust your lungs.

And as TFA pointed out you will embolize if you hold your breath above that more or less 80,000 ft altitude.

So if the acronum YMMV ever applies, it's here.

Re:Imagine drowning if you couldn't hold your brea

[tonsofpcs (687961)]

It would take nearly forever for you to cool off that much, you would explode due to pressure differential long before you would cool down, as any cooling would be due to releasing radiant heat. There is neither conductive nor convective heat loss as there is nothing cooler than you there, as there is nothing but you.

Re:Imagine drowning if you couldn't hold your brea

[pclminion (145572)]

It would take nearly forever for you to cool off that much, you would explode due to pressure differential

No, you would not. Standard air pressure is about 15 PSI. Thus, being in vacuum can never apply more than 15 PSI to your internal organs, unless you came from a substantially pressurized environment.

SCUBA divers experience sudden pressure changes in the realm of 15 PSI all the time. They don't "explode," they just get the bends. It's something you want to avoid, definitely, but you aren't going to blow your guts just because the ambient pressure drops by 15 PSI.

SCUBA decompression is different

[EmbeddedJanitor (597831)]

When a SCUBA diver decompresses, the important numbers to whatch are not so much the actual pressures as the ratio between the saturated and new pressure. A 15 PSI (1 atmoshere) change is not a problem on its own, you get that by changing depth by 10m/33ft.

You can approximately halve your saturated pressure withouth getting bends. In other words, if you have suturated to 30m (4 atm), you can rise to 10m (2 atm) without bends. If you go to the surface you're quartering your pressure which is a Bad Thing.

I've done a lot of SCUBA, some of it at high altitude (over 6000 ft). At 6000 ft, the surface pressure is far lower, so the effective decompression becomes a lot more complicated. A dive to 65m is equivalent to diving to 80+m at sea level.

In space (0 atm or thereabouts), the ratios become far harder to maintain and you would not want to be in 0atm for very long.

Bends is not something you'd want to piss about with. I know a few people who have had mild bends, even had very mild bends myself, but I also know a person who had pretty severe bends when he ran out of air at 40m or so. He was in hospital for a week or so and struggled walking for many months. In more serious cases people have died due to tissue damage in major organs/brain.

Re:Imagine drowning if you couldn't hold your brea

[bcattwoo (737354)]

No. The pressure differential is all that matters. It makes no difference if the pressure differential is 30 PSI -> 15 PSI or 15 PSI -> 0 PSI.

This isn't entirely true. Things are a little different as you begin to approach zero psi. At constant temperature, going from 30 to 15 psi, the volume of an ideal gas doubles. Going from 15 to 0 psi, the volume of an ideal gas goes to infinity.

Re:Imagine drowning if you couldn't hold your brea

[paeanblack (191171)]

It would take nearly forever for you to cool off that much

Convection and conduction will be negligible. Net loss by radiation in outer space will be on the order of 400-500W. That will drop the average body temperature about 5 C / hr. Your skin will be in bad shape pretty quickly, but it will take a day or so to turn you into a popsicle all the way through.

The joker here is evaporative cooling. Depending on the moisture on/in your skin/mouth/lungs, the human body cooling rates can sustain 10-20KW in a total vacuum. This is fatal within minutes.

The secret to staying warmer when you find yourself naked in space is to keep calm. You don't want to be sweating.

Re:Imagine drowning if you couldn't hold your brea

[MyLongNickName (822545)]

But there is almost nothing to conduct the heat. You can survive a long time in 40F degree air. Now just in 40F degree water and see how long it takes before hypothermia sets in. The difference is conduction. There would be (almost) nothing to carry away your body heat in space.

Re:Imagine drowning if you couldn't hold your brea

[Billosaur (927319)]

Exactly. The pressure differential is what will more likely kill you, though even that will take time, given the tension of cell membranes. Combine the temperature and pressure differential and you're looking at a short window of maybe 30 - 60 seconds where you get by without major physical damage and perhaps 1 - 2 minutes with some sort of major but survivable damage. And don't forget long term effects, as you will be exposed to intense solar radiation with only minimal protection.

Re:Imagine drowning if you couldn't hold your brea

[Zenaku (821866)]

As per the article:

What about the frostbite? That's actually the least plausible result of Sunshine's suitless spacewalk. The cold wouldn't cause Mace too much harm in just 15 seconds, even if he encountered the very lowest temperatures in space. That's because heat leaves the body very slowly in a vacuum.

Re:Imagine drowning if you couldn't hold your brea

[by Anonymous Coward]

we should have a new mod: -1 RTFA

Re:Imagine drowning if you couldn't hold your brea

[pegr (46683)]

You can't forget about the extreme cold. Space is a very, very cold place. One might think frostbite could be an issue.
 
It's not quite that easy. Space is not cold (nor warm). Things in space may be warm or cold. How do you lose heat in space? Well, there's no convection because there's no air. You would only lose heat via radiation, a much slower process. For the purposes of this discussion, I think you could ignore temperature, as you would perish well before a drop in heat got ya...

Re:Imagine drowning if you couldn't hold your brea

[AceJohnny (253840)]

Actually no, frostbite isn't an issue. In vacuum, there is no heat transfer through convection [wikipedia.org]. The only way to lose heat is through thermal radiation [wikipedia.org].

Convection is what will freeze you when you fall in ice-cold water.
Radiation is what will cool the beer you put in the reflective satellite dish at night.

In fact, human space modules (such as the ISS, but the ISS has to cope with atmospheric drag too, IIRC), have trouble dealing with excess heat, and have to use large surfaces to maximize radiation output

Re:Imagine drowning if you couldn't hold your brea

[jschrod (172610)]

From http://www.sff.net/people/Geoffrey.Landis/vacuum.h tml [sff.net]:

Would You Freeze?

No.

A couple of recent Hollywood films showed people instantly freezing solid when exposed to vacuum. In one of these, the scientist character mentioned that the temperature was "minus 273"-- that is, absolute zero.

But in a practical sense, space doesn't really have a temperature-- you can't measure a temperature on a vacuum, something that isn't there. The residual molecules that do exist aren't enough to have much of any effect. Space isn't "cold," it isn't "hot", it really isn't anything.

What space is, though, is a very good insulator. (In fact, vacuum is the secret behind thermos bottles.) Astronauts tend to have more problem with overheating than keeping warm.

If you were exposed to space without a spacesuit, your skin would most feel slightly cool, due to water evaporating off you skin, leading to a small amount of evaporative cooling. But you wouldn't freeze solid!

next time

[caffeinemessiah (918089)]

good thing to remember next time you're in space:

Of course, on Earth, you could hold your breath for several minutes without passing out. But that's not going to help in a vacuum. In fact, attempting to hold your breath is a sure way to a quick death.

Re:next time

[Marxist Hacker 42 (638312)]

I haven't RTFA'd yet- but IIRC, the "Asmovian" version of this required that for maximum survival, you had to hyperventalate (to maximize oxygen storage in the bloodstream), empty the lungs, and be in shadow since the sun puts out so much energy that without an atmosphere you risk a pretty bad sunburn.

Re:next time

[DaveCar (189300)]

There's only really one person who might sit in the intersection of "been in space" and "reads slashdot", so unless Shuttleworth is reading this you just wasted a minute of your life that you will never get back ;)

You can survive for 30 seconds

[Conspiracy_Of_Doves (236787)]

But the odds of being picked up by a passing space ship in that time are two to the power of 2079460347 to one against.

Re:You can survive for 30 seconds

[Thrakamazog (794533)]

...and falling

Re:You can survive for 30 seconds

[retro128 (318602)]

That's why I always make sure there's a ship somewhere in the universe that has an infinite improbability drive before I jump out of an airlock without a space suit.

2001 Movie.

[jellomizer (103300)]

Well in 2001 Dave wasn't in open space. He put his ship right next to the hanger doors creating as much as an airtight seal he could then he opened the door and all the air left his ship and filled the hanger area giving some pressure for him so his head doesn't explode but the air was rapidly thinning because it wasn't completly air tight so he only had a couple of seconds to get in. He wasn't in openspace but a low pressure envrioment, with only a few seconds of useful time.

Re:2001 Movie.

[joshv (13017)]

Seeing as how the easiest path to vacuum for air in your lungs would be through your mouth, not through your chest wall, I can't see any explosion happening. If you attempted to hold your breath during a transition to vacuum you probably feel something like a sharp kick to the chest/diaphragm as all the air is forced out of your lungs through your nose/mouth.

low-pressure spaceship env.

[fred fleenblat (463628)]

The decompression effects may be reduced/delayed if the space station uses a 100% oxygen atmosphere at a low pressure, then the pressure delta between what your body is equalized to and the vacuum is reduced so the trauma is delayed a bit.

The ISS uses normal sea-level pressure, but I believe some of the spacecraft used for the moon shots used the low-pressure environment.

Re:low-pressure spaceship env.

[evanbd (210358)]

There's a bigger problem with that though -- if you lower the pressure of the atmosphere, but add more O2 to keep the partial pressure the same, you increase the fire hazard. Inert gases like nitrogen act as a buffer and reduce flammability. Fires in spacecraft are a big deal, which (I believe) is why ISS uses higher pressure.

The major problem with exposure to vacuum isn't the pressure anyway, it's the lack of air. Furthermore, you can't hold your breath, because your lungs aren't strong enough to hold in the air. Without any air in your lungs, you get about 10-15 seconds of consciousness.

Yup, this was a major factor in the Apollo 1 fire

[Solandri (704621)]

but I believe some of the spacecraft used for the moon shots used the low-pressure environment.

Correct. Apollo used a 100% oxygen atmosphere at a lower pressure (I think 3 psi, which approximates the partial pressure of oxygen in normal air at sea-level). When they tested Apollo 1 on the ground, they decided to use 100% oxygen. But because the test was at sea-level, it was 100% oxygen at sea-level pressure. 100% oxygen at 3 psi creates a fire which burns just like regular air at sea-level. 100% oxygen at sea-level pressure creates an inferno.

ReJust luck none of the Mercury/Gemini burnt

[redelm (54142)]

Nope. Still can't use O2 at 3psia. No quench or blanketting effect from Nitrogen. Metals (esp aluminum) burns in 3 psia almost as fast as 14.7 . Plastics become similarly combustible.

Combustion reaction kinetics aren't very pressure sensitive. Oxidant density is not controlling.

Space Activity Suit and more

[OzPeter (195038)]

The Space Activity Suit [wikipedia.org] is basically the same as jumping out of an airlock, but with pressure protection for your head only. As they say in the wikipedia article - "skin itself is actually quite airtight"

There was at least one sci-fi story back years ago where this jumping out into space thing was done. So it is not a new plot line.

Forget the big problem; important smaller problem

[weak* (1137369)]

Maybe, but once they retrieve you, if your clothing needs to be removed for any reason (e.g. medical), you're going to have shrinkage like you just did the polar bear plunge... and all in front of your unreasonably hot female costar. :(

Re:Forget the big problem; important smaller probl

[SighKoPath (956085)]

Like mentioned many times already, the cold is not the issue. It is the lack of pressure. So, wouldn't it be like using one of those vacuum pump devices? If so, clothing removal in front of your unreasonably hot female costar could be just what the doctor ordered, if she doesn't mind a bit of discoloration...

15 seconds?

[vigmeister (1112659)]

I just expelled all the air out of my lungs as best as I could and it was exactly 24 seconds before it was physically impossible to hold my breath... I felt a weird kind of giddiness -almost a mild 'hit'. Sort of like when you smoke a strong cigar and inhale.

Surely, astronauts ought to have better lung capacity than yours truly?

Cheers!

Re:15 seconds?

[Funkcikle (630170)]

Surely, astronauts ought to have better lung capacity than yours truly?

Try again whilst drunk.

Re:15 seconds?

[Ihlosi (895663)]

The lungs can't 'extract' oxygen from the blood, can they?

Lungs can't extract anything. Gas exchange in the lungs is purely driven by diffusion, which moves gasses from areas with higher partial pressure to those with lower partial pressure.

In Earths atmosphere, the partial pressure of CO2 in your blood is higher than in your lungs, so CO2 moves from your blood to the air in your lungs. The partial pressure of oxygen is higher in the air in your lungs than in your blood, so oxygen moves from the air into the blood (where it oxygenates the hemoglobin in your red blood cells, thereby keeping the partial pressure lower than it would be, allowing more oxygen to be taken up by the blood than would be possible if the oxygen simply went into solution).

Saliva boils!

[192939495969798999 (58312)]

From TFA:

"One NASA test subject who survived a 1965 accident in which he was exposed to near-vacuum conditions felt the saliva on his tongue begin to boil before he lost consciousness after 14 seconds"

sounds like after a few seconds in empty space, things get painful and gross!

Wow, and TFA is wrong, too !

[Ihlosi (895663)]

At most, an astronaut without a suit would last about 15 seconds before losing conciousness from lack of oxygen. (That's how long it would take the body to use up the oxygen left in the blood.)

First piece of BS. No, your body doesn't use up the oxygen left in the blood in 15 seconds. In a vacuum (or, more broadly speaking, in any condition where the partial pressure of oxygen is lower in the lungs than in the blood), the gas exchange in the lungs is reversed - your blood will actually become deoxygenated while passing through your lungs. After 15 seconds, your brain will get hit by a blood supply that is pretty much completely deoxygenated - it's lights out then.

And then the part about air embolism - the pressure difference from going from the inside of a spacecraft (which is most likely pressurized at less than one atmosphere) to a vacuum is much lower than the pressure difference experienced by a scuba diver surfacing from a depth of, say, just 12 meters. "Vacuum" might sound nasty, but it's the pressure difference that is the problem here.

Three magic words:

[Alsee (515537)]

Explosive
Evacuation
Bowels.

-

In space, nobody can..

[Plutonite (999141)]

..hear your frozen dick fall off.

[The author of this post understands the negligible effects of loss of heat solely through radiation in extremely short time periods, but encourages the reader to take a break and try to laugh].

been there

[starshining (998625)]

I've done 4 spacewalks and during vacuum chamber training we open our suit purge valve, allowing the pressure in the suit to drop a bit (from nominal 4.3 psi) and I did feel the sensation of the saliva bubbling; it is similar to the sensation of soda pop on your tongue. I haven't seen the movies mentioned (other than 2001), but my guess about vacuum exposure is that you are more likely to be injured by the flying debris (including your own velocity as you impact a wall or whatever) associated with sudden decompression through a hatch than by a very short exposure to 0 psi. During one chamber run, I had a water line poppet valve stick open when I disconnected from the chamber wall. The water stream broke up into droplets that immediately froze, producing an impressive shower of ice particles. Over about 5 to 10 seconds, the icing point traveled up the water stream and formed a clump around the poppet valve, sealing the leak. Oh, by the way, I tried whistling while EVA and even the nominal suit pressure is too low to produce an audible sound.

Also Star Trek Nemesis

[Omega (1602)]

<big_nerd_moment>
Data jumped from the Enterprise to the Predator without a suit (or anything other than momentum to carry him), but of course being an android he could probably better sustain the lack of air pressure, oxygen and severe UV exposure no problem. His big problem was the self-propulsion.
</big_nerd_moment>