Slashdot Mirror
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.""
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.
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
The conscensus seems to be consciousness for 10-15 seconds, no serious injury for 60 seconds to 2 minutes.
SJW: Someone who has run out of real oppression, and has to fake it.
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.
An old-timer with old-timey ideas.
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.
Technoli
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.
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. :(
The Schwartz space ain't from Spaceballs.
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.
Video Production Support
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.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
If fate makes you a motorcycle, you become a motorcycle.
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...
we should have a new mod: -1 RTFA
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)
To make laws that man cannot, and will not obey, serves to bring all law into contempt.
--E.C. Stanton
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.
GetOuttaMySpace - The Anti-Social Network
Actually no, frostbite isn't an issue. In vacuum, there is no heat transfer through convection. The only way to lose heat is through thermal radiation.
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
Misleading titles? Inflammatory blurbs? Keep in mind that Slashdot is a tabloid.
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!
Joachim
People don't write Manifestos any more -- what's going on in this world? [Frank Zappa]
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.
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.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
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).
..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].
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.
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.
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.
Engineering is the art of compromise.
Couple of rolls sounds like a reasonable makeshift pressure suit.
Engineering is the art of compromise.
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.