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Q & A: In space, no one can hear you pop.

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Most recent answer: 10/22/2007
Q:
if you go out into space without a space suit...what is the force that would tear you apart?
- Kathryn (age 9)
ps120, new york, ny
A:
[whoops, see correction below] On Earth, there is about fifteen pounds of pressure per square inch on our bodies. That is a lot pressure when you add it all up (literally TONS!!). In order for us to not be squished like stomped grapes, our bodies have to push out against all that air. If you were to go out into space without a spacesuit, the pressure that the atmosphere exerts on you (the air pressure) would no longer be there. It would be like pushing on a door with all your weight, and then someone on the other side opens the door, causing you to fall through. In space your body would suddenly be pushing against nothing. So a personís body would tear itself apart with fifteen pounds per square inch. Ouch! So there is no new force on a person in space, rather there is a lack of force (air pressure) that was previously keeping a personís body in equilibrium.

(published on 10/22/2007)

Follow-Up #1: whoops- we stand corrected

Q:
This is completely false. Your body certainly would not "tear itself apart". This man who has given this explanation has watched too many science fiction B movies. A humanís skin is very elastic. During suit testing trials for the Apollo space program, there was an instance where there was a pressure suit failure while inside a vacuum chamber that was decompressed down to vacuum. As the suit failed, the occupant said he could feel the saliva boiling off of his tongue, and after about 15 seconds, he lost conciousness. There was some capillary damage on the surface of his skin however. But he was not "blown apart". Simply put, you would have between 10 and 15 seconds of useful conciousness. After this, your brain would quickly starve of oxygen and you would pass out. If you were not repressurized within 90 seconds, you would begin to experience hypoxia, which is loss of oxygen within the bodies tissues. The, your heart stops, and youíre dead. But you donít "blow apart". After being dead for awhile, Iím sure you would freeze solid in deep space, or re-enter and burn up if you were in the vicinity of a planetary body.
Kind of like in mission to Mars when that guy pops his helmet off. By far, the most realistic version of decompression in space was seen in 2001 A Space Odyssey where Dave Bowman doesnít have his space helmet and HAL wonít "open the pod bay door". And also, in deep space, I mean, really deep space, with temperatures at or near absolute zero, youíd freeze instantly and not even know what happened to you. In the 1950ís, Joe Kittenger, a high altitued ballon test pilot went up to over 102,000 feet where itís virutally space and it is very close to vacuum, his glove malfuntioned and lost pressure.. His hand swelled up a bit and he lost movement and function. But his hand did not explode. Once repressurized, everything was normal. This fallacy about people exploding in space is just outlandish. Either way, itís a quick easy death.
- Claudius Jaeger (age 37)
Colorado Springs, CO USA
A:
Claudius- Thanks for the correction. We've tried to go over our old (and new) answers to remove many errors, but we're bound to miss some without the help of knowledgable readers like you.

Mike W.

p.s. One thing I would dispute is your assertion that 'in really deep space you'd freeze instantly'. No matter how deep the space, the processes by which heat is removed (largely radiative) are not especially fast. (Also, the processes by which heat gets to your outer skin would not speed up.) I believe you'd freeze much more slowly than you would in, say, a chamber with a lot of dry ice in it, which is not nearly as cold as deep space but has faster mechanisms (e.g. convection) of carrying heat away. Think of the difference between being in cold water and cold air.

So you see how hard it is to write these things and not make mistakes.

(published on 10/22/2007)

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