Atmospheric pressure & the vacuum of space

[leviterande]

I have a question I long pondered and couldn't find any explanation to exactly what I want.
We all know that atmospheric pressure is due tu gravity acting upon everything on earth. this pressure act from all directions on all our body molecules.

However in space there is no gravity, no air, no such pressure, right? well, how can any shuttle, let alone astronauts get in ONE piece in space in the first place! shouldn't they explode from the inside out? shouldn't their molecules go apart because of the lack of the pressure?

There was one experiment where a steel cube-put inside a partial vacuum box- melted or detached from itsself apart internally. which makes perfect sense since without pressure matter can't hold itself.


Im really puzzled

regards

 

[krd]

However in space there is no gravity, no air, no such pressure, right? well, how can any shuttle, let alone astronauts get in ONE piece in space in the first place! shouldn't they explode from the inside out? shouldn't their molecules go apart because of the lack of the pressure?

No. Because the lack of pressure - the sucking force, isn't that strong. If you notice astronauts when they're doing a space walk, their suits puff out - in normal pressure the suits are floppy. That's as strong as the vacuum gets.

There was one experiment where a steel cube-put inside a partial vacuum box- melted or detached from itsself apart internally. which makes perfect sense since without pressure matter can't hold itself.

That didn't happen. And matter holds itself together in the vacuum by all the other forces.

If the vacuum was infinitely strong it would suck all of our atmosphere out into outer space - this does not happen.

There are vacuums all around you. Nature may abhor them, but it doesn't mean they're impossible. An ordinary light bulb, has a vacuum in it - to stop the tungsten burning. If the vacuum breaks the tungsten burns.

 

[leviterande]

Alright. let me just explain a little further, I by no means understand exactly this.

on both sides of your hand you have tremendous pressure, if you were to remove the pressure on 1 side of your hand, your hand would be thrown out/cut off by the left opposing pressure from the other side. all this pressure is removed in vacuum, so how are there no effects, that is what I still don't understand

 

[russ_watters]

Spaceships are pressurized. The materials used can quite easily handle the few psi of pressure.

 

[PJC01]

Thank you for your question. I can understand your confusion about atmospheric pressure and the vacuum of space. Let me try to explain it in simple terms.

Firstly, atmospheric pressure is indeed due to the force of gravity acting on all objects on Earth. This pressure is created by the weight of the air above us, which pushes down on the surface of the Earth. However, it is important to note that atmospheric pressure does not act on individual molecules, but rather on the entire column of air above us.

In space, there is no atmosphere and therefore no atmospheric pressure. However, this does not mean that there is no pressure at all. In fact, there is a different type of pressure called "vacuum pressure" or "space pressure" which is caused by the presence of particles and radiation in space. This pressure is extremely low compared to atmospheric pressure on Earth, but it still exists.

Now, regarding your question about how objects and astronauts can survive in the vacuum of space without exploding. The key is in understanding the difference between external and internal pressure. In the experiment you mentioned, the steel cube melted or detached from itself because the external pressure (space pressure) was greater than the internal pressure of the cube. This caused the cube to collapse under the external pressure.

In the case of a spacecraft or an astronaut in space, they are able to survive because they are pressurized from the inside. This means that the internal pressure of the spacecraft or the spacesuit is higher than the external pressure of space. This creates a balance of pressure and prevents the objects from exploding.

Additionally, spacesuits and spacecraft are designed to withstand the vacuum of space and are made of materials that can withstand the low pressure. So, they do not fall apart or explode due to the lack of atmospheric pressure.

I hope this explanation helps to clear up your confusion. If you have any further questions, please feel free to ask. Science is all about asking questions and seeking answers, so keep pondering and seeking knowledge. Best regards.