What would happen if we created a giant bendy straw that stretched from the surface of the earth into outer space?
Would air get sucked into space, would the vacuum of space reach the start of the straw. Could we use a machine to suck some space into the earth, Or would nothing happen at all?
Nothing at all would happen. The air inside the tube, just like the air outside the tube is attracted by the gravity of the earth. It’d stay right where it is, though it would no longer mix with the air on the outside of the tube.
If you put stairs on the tube, however, it might make a great way to get a better view of the area.
Indeed. Why would a column of air behave differently simply because you built a wall around it?
I thought it may behave differently because it broke through the skin of the atmosphere and had a direct link with the vacuum of space. Kinda like when a window is broken on a plane in the movies.
I appreciate that our atmosphere itself is in direct contact with the ‘vacuum of space’ tm
but thought a punture as it were that went deeper into space might have some effect
There would be no cross-section of atmosphere inside the straw
The atmosphere doesn’t have a skin.
I’ve been meaning to ask something like this. What would happen if we built this, and then pumped out the air from the bottom? Would it refill from the scant atmosphere in semi-outer space to the same pressure as before the pumping, or would it only refill to the pressure in the outer atmosphere?
ETA: it seems to me that it would eventually equilibriate with the rest of the atmosphere, pressure wise. But how long would this take, starting from a near-vacuum and only being exposed to fresh air from the top of the atmosphere? And would the mixture be much different than the atmospheric mixture currently at ground level?
Like pudding, the skin of the Atmosphere is the best part…
If we pumped air out would the atmosphere become thicker and move closer to the surface or the earth?
It’s basically the exact same question as “What if I put a straw in a glass of water?”
Sure, the transition from water to air is far more abrupt than the transition of Earth’s atmosphere to the vacuum of space, but the same principle applies. Nothing compels the water to be sucked up and out of the straw just because the top of the straw is in contact with the lower pressure air above. The principles of hydrostatics don’t care whether a straw surrounds that particular column of fluid or not.
But if I suck the straw the water comes out. Doesn’t space suck a bit?
Vacuum doesn’t suck, it’s the pressure that wants to expand.
Yep. And the atmosphere can’t expand into space (anymore than it already does) because gravity is holding it down. This is true whether the air in question is inside or outside of the mega-straw.
The atmosphere on earth wants to expand to the vacuum of space but it can’t overcome the pull of gravity.
It’s not like the skin of an inflated ballon that keeps the atmosphere here, it’s the gravity of the planet.
Insofar as ‘suck’ means anything, space is already sucking on the top of the atmosphere anyway. Of you want to replicate this with water, put a straw in the neck of a bottle of water, then enclose the neck of the bottle- straw and all - with your mouth and suck. Nothing should come out.
Well hello there, sailor!
If people would just remember this simple idea, we wouldn’t be subjected to various nonsensical scenarios in science fiction movies. If there’s a hole in your ship, the air inside the ship blows out into space, and then that’s it. The only force involved is the pressure of the air inside the ship escaping out the hole.
but the vacuum in Spaceballs is scientifically sound, right?
Obviously, and the movie also accurately portrayed that raspberry is the best flavor to jam a radar.
The misunderstanding is quite forgivable, IMO. Consider how alien, to the layman, it seems that the soda in a glass is being pushed up the straw, or that the dirt and air in the carpet is being pushed into the vacuum cleaner hose, or that a strand of spaghetti is being pushed into your mouth. It’s not very intuitively obvious.
It would end up the same pressure as the outside atmosphere is. Gravity would keep pulling air down and that would keep air flowing into the open top until the pressure inside the tube was the same as the pressure outside the tube.
I don’t know how long this would take (it’s going to depend on how high your tube is) or what the mixture of gases will be inside the tube.