If there was a hole in the ISS, would everyone get sucked out like in Sci-Fi movies?

Submitted by hobbitlover t3_12337br in askscience

Just watched the movie Life, and like in every space Sci-Fi movie there's an open hatch at one point and all the air gets sucked out, threatening to pull everyone out into space. I can see some violent air movement when the decompression happens, but it doesn't seem possible that that movement could sustain itself for long enough to be a problem.

Does anybody know what would really happen? I know there was one small hole in the ISS and nothing happened - a slight drop in the pressure that they let the crew sleep through and a small patch.

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kompootor t1_jdu1n6t wrote

For a spacecraft pressurized at 1 atmosphere, a puncture would cause the nearby air (and anything that it can blow with it) to move surprisingly slowly and gently compared to what's depicted in Hollywood. The correct speed of a fluid being sucked out into space is depicted in season 1 of The Expanse (nsfw gory clip). You can do a back-of-the-envelope calculation of this pretty easily (I forget the exact number) and you'll find that the flow of air is being sucked out is the same regardless of the size of the hole (for a puncture larger than a pinhole and smaller than the entire wall).

Also, the force felt from the vacuum is highest near the puncture -- it's a pressure gradient that quickly feels negligible as one moves inward into the ship -- i.e., as more of the ship's air lies between you and the puncture.

So if you're ever in hand-to-hand combat with a vicious alien xenomorph queen, about to be ripped to shreds, and your last hope is to release the air lock... then it was nice knowing you.

[I'm being exceptionally lazy with this comment -- mixing different quantities in the same description, not bothering to look up further reading for you, etc. -- probably because I know the calculation's somewhere in my notes from the past couple years but I can't find it offhand. At the end of the day though, until I either show the math or show other sources, it all just looks bad.]

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RoomyPockets t1_jdu2v9s wrote

Just a technicality: the air is blown into space, not sucked into space. It's the internal pressure of the air that causes it to rapidly expand into the vacuum. As to whether it will take you out with it, that's down to how big the hole is. If left unchecked, the air will keep escaping until there's a vacuum left inside the ship.

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Cheetahs_never_win t1_jdud4a5 wrote

Your car tire is around 35 psig, such is about 20 psig higher than atmosphere.

A puncture in your car tire is more eventful than a hull puncture, ignoring your imminent suffocating, unless your hull comes extra pressurized.

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Hugh_Mann123 t1_jdujkj4 wrote

Replying to kompootor (#2,384,985)

>So if you're ever in hand-to-hand combat with a vicious alien xenomorph queen, about to be ripped to shreds, and your last hope is to release the air lock... then it was nice knowing you.

Damn

If blowing the airlock isn't going to work, how do you actually deal with this scenario?

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hal2k1 t1_jduqtzl wrote

Vacuums don't suck. Rather pressure presses. The air pressure inside the ISS pushes the air in the ISS out through a hole in the hull.

So if you are near the hole in the hull the air in the middle of the ISS that is pressing to get out the hole in the hull pushes on you as well. If however you were near the wall furthest away from the hole in the hull there wouldn't be much air behind you (with respect to the hole) pushing you towards the hole. So you would likely die from lack of air eventually rather than via being pushed out the hole.

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ThePufferfishJeff t1_jdv47x2 wrote

Replying to RoomyPockets (#2,385,148)

Double technicality here: sucked would still work since the mechanics of sucking is to create a vacuum in one area making a pressure gradient that pushes things into the vacuum.

For example when you suck in air into your lungs you actually just expand your lungs leaving an area of low pressure that forces and shoves it's way into them filling them up. Since the mechanics are the same id argue that suck would be fine in this use

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OneFutureOfMany t1_jdvu8xj wrote

In a massive environment (imagine an school/office building sized space station) without bulkheads where a hatch was open to Vacuum, the wind/pressure would be ridiculous and would last for a long time.

No sane engineer would design such a station.

But SciFi likes to imagine they would.

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OneFutureOfMany t1_jdvumb4 wrote

Replying to ThePufferfishJeff (#2,389,879)

How people conceptualize it is slightly different depending on the wording, I'd say.

The example above... if you were at the far end of the station from the hole, you'd feel close to nothing except the air leaving you. There is no "suck" feeling.

When many/most people think of "sucking" they sort of envision a force that would permeate the internal structure and suck at everything.

Instead, talking about the atmosphere "pushing", it's intuitively obvious that if you're at the far bulkhead, you feel almost no force.

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MasterPatricko t1_jdyne1i wrote

Replying to ZZ9ZA (#2,408,228)

Quite easy. Atmospheric pressure = 14psi (pounds per square inch) = 100000 Pascal = 10 Newtons / centimeter^2.

The total force acting over a dime-sized hole is about 10 Newtons or the equivalent weight of a ~2-pound object on earth. Paper or thin card might tear but a piece of strong multilayer corrugated cardboard should be fine. Might need to give it some help sealing (glue or something) too.

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emil_badraddin t1_jdzcmfs wrote

In reality, if there was a hole in the International Space Station (ISS), the air inside the ISS would indeed rush out of the hole due to the lack of atmospheric pressure in space. However, contrary to what is often portrayed in science fiction movies, it is unlikely that the crew members would be instantly sucked out into space.

The pressure drop would initially create a strong airflow out of the hole, but eventually, the airflow would slow down and eventually stop once the air pressure inside the ISS equalizes with the vacuum of space. The speed at which the air rushes out would depend on the size of the hole, the pressure difference between the inside and outside of the ISS, and the location of the hole.

To prevent the crew from being sucked out into space, the ISS is designed with multiple pressure compartments. In the event of a hull breach, the compartments can be sealed off from each other to prevent the entire station from depressurizing. Additionally, the ISS is equipped with emergency procedures and equipment, such as spacesuits and oxygen masks, to protect the crew in case of a depressurization event.

In 2018, a small hole was discovered on the ISS, and the crew was able to patch it with sealant and tape until a more permanent fix could be made. While it was not a significant threat to the crew, it served as a reminder of the importance of maintaining the integrity of the ISS and the need for rapid response to any issues that may arise

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