is it true that your head explodes in space if you take off your helmet?

Question

It just sounds so impossible but if its true why does it happen

Answer 1

heres a WONDERFUL article explaining a bit on the subject.
its a good read !!!
http://www.sff.net/people/geoffrey.landis/vacuum.html

brought to you today by Geoffrey A. Landis
http://en.wikipedia.org/wiki/Geoffrey_A._Landis

Answer 2

How long can a human live unprotected in space?

If you don't try to hold your breath, exposure to space for half a minute or so is unlikely to produce permanent injury. Holding your breath is likely to damage your lungs, something scuba divers have to watch out for when ascending, and you'll have eardrum trouble if your Eustachian tubes are badly plugged up, but theory predicts -- and animal experiments confirm -- that otherwise, exposure to vacuum causes no immediate injury. You do not explode. Your blood does not boil. You do not freeze. You do not instantly lose consciousness.

Various minor problems (sunburn, possibly "the bends", certainly some [mild, reversible, painless] swelling of skin and underlying tissue) start after ten seconds or so. At some point you lose consciousness from lack of oxygen. Injuries accumulate. After perhaps one or two minutes, you're dying. The limits are not really known.

You do not explode and your blood does not boil because of the containing effect of your skin and circulatory system. You do not instantly freeze because, although the space environment is typically very cold, heat does not transfer away from a body quickly. Loss of consciousness occurs only after the body has depleted the supply of oxygen in the blood. If your skin is exposed to direct sunlight without any protection from its intense ultraviolet radiation, you can get a very bad sunburn.

At NASA's Manned Spacecraft Center (now renamed Johnson Space Center) we had a test subject accidentally exposed to a near vacuum (less than 1 psi) in an incident involving a leaking space suit in a vacuum chamber back in '65. He remained conscious for about 14 seconds, which is about the time it takes for O2 deprived blood to go from the lungs to the brain. The suit probably did not reach a hard vacuum, and we began repressurizing the chamber within 15 seconds. The subject regained consciousness at around 15,000 feet equivalent altitude. The subject later reported that he could feel and hear the air leaking out, and his last conscious memory was of the water on his tongue beginning to boil.

Aviation Week and Space Technology (02/13/95) printed a letter by Leonard Gordon which reported another vacuum-packed anecdote:

"The experiment of exposing an unpressurized hand to near vacuum for a significant time while the pilot went about his business occurred in real life on Aug. 16, 1960. Joe Kittinger, during his ascent to 102,800 ft (19.5 miles) in an open gondola, lost pressurization of his right hand. He decided to continue the mission, and the hand became painful and useless as you would expect. However, once back to lower altitudes following his record-breaking parachute jump, the hand returned to normal."

Answer 3

Absolutely. But dear, did Mom not tell you not to smoke that dynamite?

Because that is what it would take to make your head explode. Space alone won't do it. It would swell it a little, but then, I can see that it might be swelling, anyway.

Martin, you are wrong. It has happened. At least one person has died, several have recovered. There is plenty of experience with this kind of stuff.

http://www.sff.net/people/Geoffrey.Landis/vacuum.html

Maybe the Myth Busters need to do a show?

Answer 4

Actually, you might be right. By taking off your helmet, you are suddenly changing the pressure of the air within the helmet & suit, causing, most likely, your body to explode or disintergrate with all the radiation around.

Or you will simply die by lack of oxygen & radiation.

Answer 5

Well think about it. The pressure difference of around 14.7 lbs/sq inch working on your body and the rush of air would very likely force the crushing of you body through the opening and the consequent mess in space would result from lungs and stomach gasea exploding.

Answer 6

Water and other body fluids will boil at normal body temperature when in a vacuum.
The exploding head theory is based on the idea that all the fluid in your head would vapourise when exposed to the vacuum of space, so your head would explode in a mist of blood, sweat and spinal fluid.
Yuk!
It has never happened, to my knowledge, but the theory seems reasonable.

EDIT - Interesting link , tends to disprove the exploding head theory (much to my disappoinment!), but I have to bow to NASA's greater expertise here:

http://www.sff.net/people/Geoffrey.Landis/vacuum.html

Answer 7

Probably not. All the air would be sucked out of you. There would be massive embolisms and hematomas, but not blasting open like a pinata.

I disagree with Martin. I don't think the difference between 14.7 lbs per sq. in. and zero is great enough to do that.

Answer 8

No.... your body doesn't contain enough pressure to 'explode', although your blood & fluids would start frothing in your lungs & out your nose & mouth.

Answer 9

No. It might burst your eardrums if you kept your mouth shut though, and if you left it off for long enough it would sort of mummify.

Answer 10

Yes it does. It's the Semtex air seal.