Q&BA: What happens to a human body if it's exposed to the vacuum of space?

[Ryuuken24]

What happens to a saturated salt solution inside a vacuum chamber?

[WiFiOnly]

I am very surprised at the fact that this video has 0 dislikes

[saivert]

@WiFiOnly ah there you go. jinxed it. now look!

[420dseifer]

Event Horizon had a scene very similar to your description of space exposure.

[jebjim7]

What do scientists expect to happen when the magnetic poles shift ?

I've heard different things . . . don't trust any of them

[everyonedoesit2]

@jebjim7 Absolutely nothing.

[lacalaca85]

@jebjim7 compasses will point the wrong way. That's all.

[jebjim7]

This was FASCINATING - and for some morbid reason I tried to visualize it as he spoke

[DrKuha]

This is great. You are awesome.

[facelessone86]

It has been done, BSG!

[sindri262]

2001 got it right in a movie. It's the only one I can think of...

[TuahShinguru]

...

Well hey, at least you'd go unconscious too quickly to experience much of it.

[astrophonix]

For my novel, Terminal Crescendo, (now available on Amazon/Kindle!) I researched what happens to a body in vacuum, and had a character survive one minute's exposure to vaccum and survive, and I used the experience a 60's technician had of the saliva boiling on their tongue.

[MumblingMickey]

Well there is a difference between reality and Hollywood... by it very nature Hollywood is 'fiction' and therefore all sorts of crazy things can happen in a movie that just do not happen in reality.

For example in the movie 'Evolution' animals morphed from one species to another. In reality of course evolution only happens slowly and even then only on entire populations.

Good science is not particularly good special effects.

And lets not even get started on the 'Back to the Future' trilogy

[sindri262]

@MumblingMickey And let's not forget the last Alien movie, where apparently the monster was so squishy that tossing it against a wall with a pinprick in it was enough to suck it out into space like the toothpaste from a tube.

[MumblingMickey]

@sindri262 You'd wonder if sticking your finger against the hole wouldn't work... ohh wait it would... but you'd get a blister if you kept it there...but perhaps a bit of duct tape might suffice... which I'd guess it would... well until you sealed it... the duct tape would freeze over time.

On the Apollo missions the pressure inside was one atmosphere...which seemed perfectly capable of being okay despite the 1mm of distance between the astronautics and open space in places.

[JimPlaysGames]

Phil is amazing!

By the way, in Babylon 5, it's not seen, but described in a way that sounds like it's fairly accurate. The only difference I can remember is that he seemed to remain conscious a lot longer than you said and when they brought him back in his eyes were frozen rather than the blood vessels having burst.

[sindri262]

@JimPlaysGames yeah, there are a lot of TV shows that get physics right. Bab 5 even had the right momentum and acceleration for space combat, instead of pretending that everything is happening in the ocean or between aircraft. IIRC Stargate was pretty good about such things too, even doing the condensation in air being sucked out an airlock properly. But big budget things like full movies tend to ignore science and give people what they expect to see, which is generally what other movies showed.

[JimPlaysGames]

@sindri262 oh yeah the way the Starfury would turn to do a strafing run past a ship while still maintaining it's momentum was very satisfying. They even calculated the speed that they would launch at based on the rotation of the station

Stargate had it's moments. As I understand it, the part where they make a star supernova by drawing some of it's mass through a gate to a black hole is pretty accurate, assuming a stargate would be possible too of course. I'd like to hear Phil's thoughts on that

[originofnoise]

Very interesting. :D

[maekern]

So how did 2001 deal with it, when Bowman had to spend a few seconds in vacuum?

[flamingacdc1]

If your blood vessels in your eyes burst they wouldn't be closed and would then not be a closed system so wouldn't it then boil because of it being an open system?

[monkybunney]

Cool stuff thanks Phil! For whatever reason this topic (and what colors were the dinosaurs?) always fascinated me as a child. I remember reading somewhere on the net about an accident, might even be the one you’re referring to, where a person was exposed to a vacuum and they said the last thing they remembered before blacking out was the feeling of their saliva boiling on their tongue!

[morcova]

If i''m hearing him right he's kind of saying that the scene from event horizon where one character gets launched from one ship to another is pretty accurate.

[EGarrett01]

Phil really is the third Mythbuster.

[PinkProgram]

If exposed to space you want to blow out hard and close your eyes as tight as you can... then you have about 30 seconds to get out of the vacuum. Then for the next few hours if you survive it you'll have the bends and soft tissue damage. A tardigrade can survive a few hours in the vacuum and radiation though. My design can probably last an hour or two of hard space... and Sylphe's design can survive centuries of cold vacuum ;3

[tiaxanderson]

@TheBadAstronomer how accurate is damninteresting's article about outer space exposure?

Also, great video as always

[5I13lV7DI1293]

Wow, thanks a ton, this is something I've always wondered. Great job phil!

[philos4r]

how much gold is there in a suit?

[Kretek]

Have you seen "Sunshine"? SF movie from 2007? There was scene were astronauts are jumping from one spaceship to another. Only one of them have space suit. It would be great if you would check this scene and tell us your opinion about it from scientific point of view. Movie itself is just fantastic, I really recommend you watch it.

[hooloovoo1st]

@Kretek I know the scene you're talking about, and it's a good one. He does appear to be very cold after getting back into the ship, but at least he wasn't frozen solid. Everything else was quite nicely done I thought. Very nicely done compared to all the other movies I've seen.

Trivia: The DVD of Sunshine has a commentary track from Brian Cox. He was a science advisor for the film.

[93tomb]

@hooloovoo1st with the obvious exception of Dave Bowman's explosive escape from the EVA pod in 2001... now there's a scene where exposure to hard vacuum is handled (almost) right :)

[93tomb]

@Kretek I don't think that movie did as well as it deserved to. I thought it was a lot of fun, but that scene bugged me. Survival would be perfectly possible, but the scene showed the astronauts freezing in seconds, which totally wouldn't happen, because the only heat loss would be radiative, and for another thing the astronauts are surrounded by two presumably warm spacecraft, with massive solar shields which would probably make very effective radiators and lend a warming effect.

[MumblingMickey]

@Kretek I seen that moviein the theater.... I was very dissapointed with it... great plot, really badly executed.

Funnily enough the main character is a real bone-fide physicist (Prof. Brian Cox) and he is also a real bone-fide rock star (the keyboard player from the band D-ream) and he's also a real bone-fide TV star hosting numerous science shows etc on TV and he's also an author (mostly of science books and whatnot)

But he chose a crappy movie to make his bid for Hollywood in....

[OneRingShort]

@Kretek While the temperature of space is -273C there, there is a massive amount of radiation being emitted by the sun at that distance. While radiation is incredibly inefficient as Phil mentioned, the Sun emits A LOT of it. I imagine the surfaces of the astronauts facing the sun would begin to bake and char very rapidly. Heat will be leaving from the opposite surfaces creating a large temperature gradient. The average temperature could be found using the Stefan-Boltzmann equation.

[lacalaca85]

@Kretek the piece in Sunshine was so-so. Vacuum is the best insulator (think of thermos flasks), so the protective blanket was a bit pointless except to soften the impact. AFAIR there was something about holding his breath - REALLY bad idea if he wanted to use his lungs or mouth/nose afterwards, because air would try to rush out quite violently.

[Frottjeif]

If I ever get around to writing my sci-fi story, I'll keep this in mind.

[Ruudsosalsa]

Dear Phil, Question about the temperature:

Wouldn't you get hot at first? Your body cannot really lose heat any more (since any sweat will boil very rapidly and not absorb much heat) apart from radiation. Your body is very well insulated (no air around it), even better than wearing arctic gear. What's your idea on this?

[93tomb]

@Ruudsosalsa Interesting question. I did some googling: first off, the latent heat of vapourisation of water is higher in vacuo than at atmospheric pressure, so evaporating sweat would actually remove _more_ heat in a vacuum. The average power produced by a human seems to be about 120 watts, based on food consumption per day. The power radiated from a person at body temperature, assuming they are a black body with surface area 1.73m^2 would be 906 watts, so you may well get colder.

[93tomb]

@93tomb On the other hand, a person is not a black body, and a person's skin, let alone any clothes they are wearing, will not be at body temperature. So I wouldn't quote me on that fact :)

[Ruudsosalsa]

@93tomb

thanks!

[93tomb]

@Ruudsosalsa no worries :)

[superdau]

Don't space suits even include COOLING units which work by evaporating water from the back? If space really were that "cold" (a funny attribute for something that contains almost no matter) as depicted in movies, why would you need to cool an astronaut instead of heating him?

I hate it when people believe stuff shown in movies so it eventually makes it into wrong common "knowledge". And it's so hard to fight against this stupidity once it's out there.

[feuchster]

@superdau Well, if you look at the temperature difference between the side of the spacestation that is faced towards the sun and the side that's in the dark, you would understand. =p

[ytmoog]

@feuchster

The temperature difference of what exactly?

[ytmoog]

@superdau

Space suits are very well insulated and are bright white to reduce radiative heating from the sun.

So the main source of heat which has to be dealt with is the body heat of the astronaut, which is removed as you state by the sublimation of water ice.

[TheBienator]

event horizon is probably the movie with the most realistic decompression scene so far

[newnaira]

@TheBienator I watched it a few nights ago and was actually shocked that the character didn't immediately freeze to death - not because I though that's what happens - but because Hollywood seems to just consistently get it wrong. I expected shenanigans and was pleasantly surprised (well, not so pleasant...).

[VarunRevamped]

Who else cringed while listening to him?

[MartianStories]

Thank you, Phil. Great vid as always.

MARS IS WORTH FIGHTING FOR!

This is why Arthur C. Clarke was right when he said that the pod ejection scene in 2001 was right (except for Dave taking a deep breath...)

[Venim85]

Mission to Mars.

Dude freezes within seconds.

[ytmoog]

@Venim85

Yea, not really that realistic.

There is not that much matter in a vacuum to carry that heat away from him :\

[CognosSquare]

Thanks Phil for being extra awesome lately.

[anunamongstus]

Corpsicle? MUuwahahahahaha!

[kalamain]

So...In Titan AE...When one of the characters tells the other to exhale and then uses a fire extinguisher to smash the cockpit window and then blast to another ship (5 seconds in space tops).

Its possible??

[musli4brekkies]

@kalamain

Sure. He tells him to exhale so his lungs wouldn't be damaged by the intense pressure of the air trying to escape. It's a bit weird that the most accurate film I've seen is animated...

[musli4brekkies]

@kalamain

Oh, yeah. They do pass out too, so it's right again :P.

[onelowerlight]

Fascinating. What about the cosmic radiation? Would your skin get cooked by that, or would it also take time for that to have any visible effect?

[musli4brekkies]

@onelowerlight

I'm just a layman throwing out ideas, but if there was enough cosmic radiation around to bake us in space wouldn't we see auroras all the time? Just a thought.