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proudlyhumble t1_jdmnht3 wrote

Reply to comment by The_Flurr in TIL: Thanks to poor internal communication at NASA, information about a spacesuit water leak wasn't properly communicated. Later, Astronaut Luca Parmitano almost drowned on a July, 2013 ISS space walk, his helmet filling with several liters of water before they could get him back inside. by OvidPerl

Not true, you’d have explosive decompression and lose consciousness within seconds. It isn’t like holding your breath. The air is sucked out of you instantaneously.

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The_Flurr t1_jdmrtvi wrote

Explosive decompression really isn't a thing. You need pressure differentials much higher than one atm to cause that sort of force.

Air isn't sucked out of you instantaneously, that's not how fluid dynamics work, you'd need a much higher differential for it.

Estimates generally give about 15-30 seconds before loss of consciousness, depending on how oxygenated your blood is.

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proudlyhumble t1_jdmu0w4 wrote

I’m not going to pretend I’m an expert on pressurization but I am an airline pilot and our charts agree with Wikipedia that it’s about 6-9 seconds of useful consciousness.

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oatscoop t1_jdn0vw1 wrote

There's a handful of cases where people were exposed to a total vacuum for a short period and survived. Here's one of them -- he was mostly unharmed.

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VoxEcho t1_jdoj1cn wrote

The reason explosive decompression can be a thing in a plane but not in space is because of the force of outside air acting on things inside of the vehicle. If something acts on an air plane to abruptly depressurize it through a sufficiently large enough hole, it isn't so much that things are "sucked" out of it as it is that things are "blown" out of it. It is the same force that makes it feel like something can get sucked out of a car window when your vehicle is in motion even though there isn't actually a meaningful pressure difference between your closed car and the outside air, it has to do more with the motion of the air along the vehicle.

In a vacuum things like gasses (air) would expand outwards through a breach, but there isn't the same force acting on a space shuttle that there is on a vehicle in motion on Earth, the popular media idea of things getting explosively decompressed out of a spaceship wouldn't actually happen outside of the force of whatever caused the breach to occur in the first place.

The force exerted by air expanding into a lower pressure area, like what would happen if you "opened the car door" so to speak, but in outer space, isn't enough to actually "suck" things out of the vehicle. Except probably really light things like paper or something, depending on how abrupt the breach was and how big (or, small) it is. You'd basically have to get sucked through a garden hose to generate enough pressure to drag a human body out of a spaceship -- and in that specific theoretical you'd block the opening with your clothing or just the weight of your body far before any actual bodily damage would occur. It probably wouldn't be fun to experience but you'd survive and with all your limbs.

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