Freezing to death in space

[JarodRussell]

I made the mistake of watching Sunshine again. Mostly because I thought to myself that it couldn't possibly have been as bad as I remember it. But I was wrong.

That said, there is a scene where one guy in a space suit, and two other guys without a space suit, jump from one ship to the other ship, in the vacuum of space.
And what happens? One guy gets lost and freezes to death. Apparently, space was so cold that his entire body froze and broke into little pieces.

That's impossible, isn't it? Vacuum does not freeze you to death, right? There is no "cold" medium, there is simply nothing. Which means that your body doesn't lose heat as much (that's the biggest problem of space ships: what to do with the produced heat? Because you can't get rid of it in space because there is no cold air or water that can absorb it). Yet the guy in the film froze to death like someone just put him in liquid nitrogen or something.


Then there was another scene, in which a guy is trapped in an airlock. He then drills a hole into the door leading into the ship, and blasts the doors leading into space. The air gets blown out through that tiny hole in the door, apparently with such a strong force that the entire door gets ripped out. Is the pressure of 1 atmosphere really that strong?

 

[farmkid]

With zero pressure, all the water in the body would rapidly boil away. All that vaporizing water would take a lot of the heat with it, so yes, a body would freeze rather quickly. If you could prevent the vaporization of water, then no, it shouldn't freeze very fast at all. Heat would be lost at the rate it radiated away, but with no convection or conduction, that shouldn't be very fast.

As for the pressure question, 1 atmosphere isn't a lot of pressure, but when you have 1 atmosphere of pressure over an entire door, then you have a lot of force on the door. I don't know how big the door was, but let's go with a standard size of a door in a house--30"X80". Atmospheric pressure is about 14 psi, so a door of that size, with 1 atmosphere on one side and a vacuum on the other would have 33,600 lbs of force spread across it.

 

[RedShirt]

With zero pressure, all the water in the body would rapidly boil away.

No, not unless you have a massive wound or something.

http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html

 

[Christopher]

You don't freeze in space. As anyone who's ever owned a Thermos should know, vacuum is an insulator. Astronauts need to worry about overheating, not freezing.

And no, the moisture in the body wouldn't boil away, because it's inside the body! The tissues surrounding it are more than adequate to maintain its pressure. Sure, your surface moisture would sublimate quickly, drying out your eyes and mouth and skin, but your blood would be fine as long as it stayed inside you where it belongs.

Also, as the Mythbusters showed a while back, the conceit of a body freezing solid and shattering like ice is bogus. That can happen to the skin and muscle to a limited extent, but not the bone. And even if the water in your cells is frozen, there's still other stuff than water making up the body. I mean, think about it. Most of us have handled frozen meats. They don't feel like ice, do they? If you can sacrifice one, try dropping a frozen chicken breast or something on the floor or smashing it with a hammer, then compare it to doing the same with a block of ice. It's not going to break the same way.


And I'm not clear on the description of the doors blowing out, but it seems bogus that just drilling a hole would have that effect. I mean, the doors are designed to have an atmosphere on one side and vacuum on the other, right? So they'd be designed to withstand the maximum amount of force that internal atmosphere could exert, and then some for a safety margin. If you puncture the door and let the air rush out, it's going to start out at that maximum pressure and swiftly drop off as the amount of internal atmosphere diminishes.

 

[JarodRussell]

And I'm not clear on the description of the doors blowing out, but it seems bogus that just drilling a hole would have that effect. I mean, the doors are designed to have an atmosphere on one side and vacuum on the other, right? So they'd be designed to withstand the maximum amount of force that internal atmosphere could exert, and then some for a safety margin. If you puncture the door and let the air rush out, it's going to start out at that maximum pressure and swiftly drop off as the amount of internal atmosphere diminishes.

Here's (an unfortunately crappy) Youtube video of the scene. The guy gets in a spacesuit, welds a hole into the door, and then blasts the other door. And then the air flowing through that tiny hole rips the entire door out.

Also, as the Mythbusters showed a while back, the conceit of a body freezing solid and shattering like ice is bogus. That can happen to the skin and muscle to a limited extent, but not the bone. And even if the water in your cells is frozen, there's still other stuff than water making up the body. I mean, think about it. Most of us have handled frozen meats. They don't feel like ice, do they? If you can sacrifice one, try dropping a frozen chicken breast or something on the floor or smashing it with a hammer, then compare it to doing the same with a block of ice. It's not going to break the same way.

I blame "Terminator 2" for that. Although it was the liquid metal Terminator that got frozen and shattered in that movie. But since then, a lot of humans have met the same fate in movies (because the effect is sooo cool).

 

[sojourner]

^Forget the link? I'd like to see this.

 

[JarodRussell]

Ha, sorry.

http://www.youtube.com/watch?v=3GBXpbsRqLA

 

[STR]

The vacuum itself wouldn't freeze anything, as previously stated, but the rapid depressurization sure would. Like a giant can of compressed air you use for your computer. The opposite is also true. Sailors on submarines that suffer a catastrophic hull breach are actually flash-fried by the compression of air by the incoming water rather than drown.

 

[RobertVA]

Spacesuits are usually designed to operate with 3 to 5 psi of oxygen inside them. Higher pressures (necessary for a mix including nitrogen) would make spacesuit joints like the elbows and knees even harder to move than they are now, and they aren't very easy to move as it is. With any significant breach in the suit or helmet that 3 to 5 psi is going to be pushing any air in your lungs out your mouth and nose with a significant amount of force. Soon there will be very little air in your lungs and little oxygen in your blood stream. You're going to pass out from the lack of oxygen well before you have time to experience much in the way of hypothermia or decompression sickness. You might remain concious long enough to feel you ear drums blow out and your tears and saliva boil away (which would be more of a dry fizzing sensation, water boiling at low temperature in a vacuum).

I don't know to what extent conduction to handrails and tools is involved, but from what I gather the gloves for the USA built EVA suits are equipped with electrical heating elements for the approximately 45 minute periods when the station is within the Earth's shadow.

 

[Owain Taggart]

That's a good explanation, Christopher. It's one of those common mistakes that Sci-fi movies often make. Mistakes like that, when movies could be made better with more research, peeve me.

 

[Gil T.Azell]

And I'm not clear on the description of the doors blowing out, but it seems bogus that just drilling a hole would have that effect. I mean, the doors are designed to have an atmosphere on one side and vacuum on the other, right? So they'd be designed to withstand the maximum amount of force that internal atmosphere could exert, and then some for a safety margin. If you puncture the door and let the air rush out, it's going to start out at that maximum pressure and swiftly drop off as the amount of internal atmosphere diminishes.

Here's (an unfortunately crappy) Youtube video of the scene. The guy gets in a spacesuit, welds a hole into the door, and then blasts the other door. And then the air flowing through that tiny hole rips the entire door out.

Also, as the Mythbusters showed a while back, the conceit of a body freezing solid and shattering like ice is bogus. That can happen to the skin and muscle to a limited extent, but not the bone. And even if the water in your cells is frozen, there's still other stuff than water making up the body. I mean, think about it. Most of us have handled frozen meats. They don't feel like ice, do they? If you can sacrifice one, try dropping a frozen chicken breast or something on the floor or smashing it with a hammer, then compare it to doing the same with a block of ice. It's not going to break the same way.

I blame "Terminator 2" for that. Although it was the liquid metal Terminator that got frozen and shattered in that movie. But since then, a lot of humans have met the same fate in movies (because the effect is sooo cool).

Actually there was a scene in the original V where a worker at a plant had his fore-arms frozen when he bumped into a gard railing his for arms shattered.

 

[Deckerd]

So to sum up: getting blown through a pressure door might pulverize you but once in space nothing much would immediately happen apart from suffocating and a drying out of surface moisture.

 

[Chaos Descending]

Also, as the Mythbusters showed a while back, the conceit of a body freezing solid and shattering like ice is bogus. That can happen to the skin and muscle to a limited extent, but not the bone. And even if the water in your cells is frozen, there's still other stuff than water making up the body. I mean, think about it. Most of us have handled frozen meats. They don't feel like ice, do they? If you can sacrifice one, try dropping a frozen chicken breast or something on the floor or smashing it with a hammer, then compare it to doing the same with a block of ice. It's not going to break the same way.

To be completely fair, it all depends on the temperature.

Sure, a zero Celsius human body wouldn't shatter, but what about maybe -100 C? Certainly the temperatures produced by liquid nitrogen would do it.

The colder you get the more brittle the crystalline arrangement would be.

However, I do agree with you that exposure to the vacuum of space wouldn't get the job done.

 

[Lindley]

Out of curiosity, how inaccurate would all of this make the "spacewalk" scene in Farscape's "Look at the Princess"? I mean, the notion of an energy weapon being used for action/reaction directional control is a bit curious, but other than that, is it plausible?

 

[RapidNadion]

So essentially, this validates the Geordi/Beverly scene in TNG: "Disaster" when they decompressed the cargo bay. With the exception of holding their breath (which, as I understand it, would lead to some serious lung damage) they held up just fine when exposed to a vacuum, and Beverly's pre-blast briefing seems legit.

 

[STR]

^no, decompressing something like that would flash freeze everything, at least any exposed surfaces (like skin). The vacuum is not the problem, creating the vacuum is. The whole principle is how refrigerators and air conditioners work. It's all the same stuff. Compressing matter heats it, decompressing it cools it.

 

[RobertVA]

^no, decompressing something like that would flash freeze everything, at least any exposed surfaces (like skin). The vacuum is not the problem, creating the vacuum is. The whole principle is how refrigerators and air conditioners work. It's all the same stuff. Compressing matter heats it, decompressing it cools it.

Not entirely true.

Refrigeration systems use a combination of refrigerant pressure changes and the change of the refrigerent's state between liquid and gas. there's quite a bit of energy that can be picked up or dropped without a temperature change in the processes of evaporation and condensation.

Pressure changes aren't going to make much difference to a solid or liquid until that boiling process takes place because their volume changes a relatively small amount in connection with expansion and contraction. This is why a hydraulic elevator cannot drop at a dangerous rate (the fluid can't escape through the restriction point at the base any faster).

 

[STR]

Phase change is important for sustaining the closed cycle of an AC unit, but isn't important if you're going to rapidly dump coolant out into space in an open cycle.

 

[RobertVA]

But since relatively little of the human body is normally covered with moisture the liquid to boiling phase change would only have an immediate effect on the surface of the eyes, nasal passages and oral/throat passages. The rest of the body would only be cooled by radiation, in most cases protected by clothing, in 2001's Dave Bowman case all but the head was covered by his helmetless space suit. While he rapidly depleted his air supply he would experience a brief chilling effect on the exposed moist areas, followed by an extreme dryness. I'm wondering if he would have trouble closing his eyelids to blink without some supplemental source of moisture.

On the door blow out issue: To a great extent the seriousness would depend on the door materials, the door design and how it was holed. A very heat conductive material like an aluminum alloy cut with a heat source that's barely hot enough to melt the metal might be subject to significant weakening during the long melting process and might be subject to a relatively large patch suddenly melting away when the melting point is finally reached.

 

[RoJoHen]

Out of curiosity, how inaccurate would all of this make the "spacewalk" scene in Farscape's "Look at the Princess"? I mean, the notion of an energy weapon being used for action/reaction directional control is a bit curious, but other than that, is it plausible?

It seems reasonably plausible to me, especially when you take into account the rough shape he was in when he got back inside.