If the Space Station could spin on a central axis how much speed would it need to create gravity?

[BULLDOG]

I don't think the space station is designed for the perimeter to be used as a floor. That might be something to consider if another is built.

No doubt it isn't. I just don't get why. Cost? Technical restraints? Risk?

I think that there is an enormous cost to countering the gyroscopic effect of a spinning disk as it orbits a large body like the Earth.

If you're not familiar, take a bike tire and find a way to hold the axle part of the wheel, then spin it real fast. Then, sit on a stool that can turn and turn the wheel. You'll start turning as the centrifugal force exerts itself.

ETA:

This isn't being done in a vacuum. HUUUUUGE dif.

So? You think angular momentum is negated in a vacuum? A gyroscope, which his experiment demonstrates, works fine.in a vacuum. How do you think they maintain their attitude instead of spinning wildly?

Nope. I never said that. In atmosphere though, the friction of the air has a huge effect that you need not worry about in space. That is the point I was making. It removes one very significant variable.

Astronauts in the space station don't wear zero atmosphere gear. There is an atmosphere. If the station were rotating, the atmosphere would be rotating right along with it.

 

[jon_berzerk]

All objects with gravity are due to its magnetic core and the field of flux..Normally an iron core...Just like in yer transformers.

You've never stuck to the wall of a spinning barrel at an amusement park have you lol

that is not really gravity

if it was we all would be flung off the face of the earth

It's syntrifical force which is the same thing I'm talking about.

And if not for the gravity of the earths mass we would fly off as a result of the rotation.

actually centripetal force is what is required in your space ship to create artificial gravity

Takes both. Centrifugal force. or "apparent" force pushes outward from the central rotating point holding the astronauts to the circumference of the station. Centripetal force is exerted by the shell towards the center rotating point, counteracting the centrifugal force.

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

 

[martybegan]

All objects with gravity are due to its magnetic core and the field of flux..Normally an iron core...Just like in yer transformers.

You've never stuck to the wall of a spinning barrel at an amusement park have you lol

The problem is this doesn't create "gravity" which is caused by the intrinsic properties of mass. What it creates is centripetal force, which can simulate but not truly replace gravity.

The real issue isn't the rotation speed itself, it's getting the required force gradient at a LOW enough speed that there is as small a head to foot gradient in the force as possible.

What you don't want is a person's legs feeling a much different force than their head.

This I can relate to based on my memory of that ride. That ride which caused a lot of people to puke lol. So much so that there was a warning about it before you got on.

You could also notice it if you kept your hands out before the ride was going too fast. you could keep your arms out because the force was decreased greatly away from the wall (because the radius of the cylinder was so small)

I dont think that was possible. The ride was probably 20 or 30 feet across. It was a really bizarre experience

The one I was in at Great Adventure in NJ was about only 15 ft in diameter. and once you broke your arms free of the wall keeping them out was much easier.

 

[jon_berzerk]

You've never stuck to the wall of a spinning barrel at an amusement park have you lol

The problem is this doesn't create "gravity" which is caused by the intrinsic properties of mass. What it creates is centripetal force, which can simulate but not truly replace gravity.

The real issue isn't the rotation speed itself, it's getting the required force gradient at a LOW enough speed that there is as small a head to foot gradient in the force as possible.

What you don't want is a person's legs feeling a much different force than their head.

This I can relate to based on my memory of that ride. That ride which caused a lot of people to puke lol. So much so that there was a warning about it before you got on.

You could also notice it if you kept your hands out before the ride was going too fast. you could keep your arms out because the force was decreased greatly away from the wall (because the radius of the cylinder was so small)

I dont think that was possible. The ride was probably 20 or 30 feet across. It was a really bizarre experience

The one I was in at Great Adventure in NJ was about only 15 ft in diameter. and once you broke your arms free of the wall keeping them out was much easier.

puke machines --LOL slams right up on the person next to ya

--LOL

 

[Harry Dresden]

The concept is obviously sound so why is it not done to help the astronauts with muscle atrophy?

Can artificial gravity be created in space? (Intermediate) - Curious About Astronomy? Ask an Astronomer
https://www.quora.com/How-large-would-the-rotating-spacecraft-have-to-be-for-simulated-gravity-in-“Interstellar”-to-work

 

[jon_berzerk]

 

[Moonglow]

Don't ferget the electromagnets..

 

[BULLDOG]

You've never stuck to the wall of a spinning barrel at an amusement park have you lol

that is not really gravity

if it was we all would be flung off the face of the earth

It's syntrifical force which is the same thing I'm talking about.

And if not for the gravity of the earths mass we would fly off as a result of the rotation.

actually centripetal force is what is required in your space ship to create artificial gravity

Takes both. Centrifugal force. or "apparent" force pushes outward from the central rotating point holding the astronauts to the circumference of the station. Centripetal force is exerted by the shell towards the center rotating point, counteracting the centrifugal force.

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

Yes, and centrifugal force, (think of the force that makes a tether ball swing away from the pole instead of hanging down) is what presses the astronauts to the outside shell/floor.

 

[jon_berzerk]

that is not really gravity

if it was we all would be flung off the face of the earth

It's syntrifical force which is the same thing I'm talking about.

And if not for the gravity of the earths mass we would fly off as a result of the rotation.

actually centripetal force is what is required in your space ship to create artificial gravity

Takes both. Centrifugal force. or "apparent" force pushes outward from the central rotating point holding the astronauts to the circumference of the station. Centripetal force is exerted by the shell towards the center rotating point, counteracting the centrifugal force.

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

Yes, and centrifugal force, (think of the force that makes a tether ball swing away from the pole instead of hanging down) is what presses the astronauts to the outside shell/floor.

go back and watch the youtube posted a few posts back to understand

 

[BULLDOG]

It's syntrifical force which is the same thing I'm talking about.

And if not for the gravity of the earths mass we would fly off as a result of the rotation.

actually centripetal force is what is required in your space ship to create artificial gravity

Takes both. Centrifugal force. or "apparent" force pushes outward from the central rotating point holding the astronauts to the circumference of the station. Centripetal force is exerted by the shell towards the center rotating point, counteracting the centrifugal force.

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

Yes, and centrifugal force, (think of the force that makes a tether ball swing away from the pole instead of hanging down) is what presses the astronauts to the outside shell/floor.

go back and watch the youtube posted a few posts back to understand

I have.

 

[jon_berzerk]

actually centripetal force is what is required in your space ship to create artificial gravity

Takes both. Centrifugal force. or "apparent" force pushes outward from the central rotating point holding the astronauts to the circumference of the station. Centripetal force is exerted by the shell towards the center rotating point, counteracting the centrifugal force.

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

Yes, and centrifugal force, (think of the force that makes a tether ball swing away from the pole instead of hanging down) is what presses the astronauts to the outside shell/floor.

go back and watch the youtube posted a few posts back to understand

I have.

obviously you did not understand it

 

[BULLDOG]

Takes both. Centrifugal force. or "apparent" force pushes outward from the central rotating point holding the astronauts to the circumference of the station. Centripetal force is exerted by the shell towards the center rotating point, counteracting the centrifugal force.

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

Yes, and centrifugal force, (think of the force that makes a tether ball swing away from the pole instead of hanging down) is what presses the astronauts to the outside shell/floor.

go back and watch the youtube posted a few posts back to understand

I have.

obviously you did not understand it

Believe what you will. I don't care.

 

[toobfreak]

The concept is obviously sound so why is it not done to help the astronauts with muscle atrophy?

You would need to redesign it. Here is a concept drawing by Werner von Braun from 1952, the guy who basically designed our rockets and space program:

So it would depend on the radius. Centripetal force (artificial gravity effect) would be v^2/r at a distance r from the center of rotation. So to get 1 g (Earth gravity at sea level) at 100 meters radius, you would have to go about 98 feet per second. That would amount to about 3 rpm. Obviously cost is a factor, plus the fact that up till now, they've been studying the effects of weightlessness, but to go to Mars, there will HAVE TO BE some form of rotating section.

 

[jon_berzerk]

Artificial gravity can be created using a centripetal force. A centripetal force directed towards the center of the turn is required for any object to move in a circular path. In the context of a rotating space station it is the normal forceprovided by spacecraft's hull that acts as centripetal force.


Artificial gravity - Wikipedia

Yes, and centrifugal force, (think of the force that makes a tether ball swing away from the pole instead of hanging down) is what presses the astronauts to the outside shell/floor.

go back and watch the youtube posted a few posts back to understand

I have.

obviously you did not understand it

Believe what you will. I don't care.

i will believe Newton and his laws over you any day

 

[martybegan]

The problem is this doesn't create "gravity" which is caused by the intrinsic properties of mass. What it creates is centripetal force, which can simulate but not truly replace gravity.

The real issue isn't the rotation speed itself, it's getting the required force gradient at a LOW enough speed that there is as small a head to foot gradient in the force as possible.

What you don't want is a person's legs feeling a much different force than their head.

This I can relate to based on my memory of that ride. That ride which caused a lot of people to puke lol. So much so that there was a warning about it before you got on.

You could also notice it if you kept your hands out before the ride was going too fast. you could keep your arms out because the force was decreased greatly away from the wall (because the radius of the cylinder was so small)

I dont think that was possible. The ride was probably 20 or 30 feet across. It was a really bizarre experience

The one I was in at Great Adventure in NJ was about only 15 ft in diameter. and once you broke your arms free of the wall keeping them out was much easier.

puke machines --LOL slams right up on the person next to ya

--LOL

usually they kept the ride under 2 minutes, I have a feeling that was created by the "puke factor"

 

[jon_berzerk]

This I can relate to based on my memory of that ride. That ride which caused a lot of people to puke lol. So much so that there was a warning about it before you got on.

You could also notice it if you kept your hands out before the ride was going too fast. you could keep your arms out because the force was decreased greatly away from the wall (because the radius of the cylinder was so small)

I dont think that was possible. The ride was probably 20 or 30 feet across. It was a really bizarre experience

The one I was in at Great Adventure in NJ was about only 15 ft in diameter. and once you broke your arms free of the wall keeping them out was much easier.

puke machines --LOL slams right up on the person next to ya

--LOL

usually they kept the ride under 2 minutes, I have a feeling that was created by the "puke factor"

indeed related to the alcohol factor --LOL

 

[jon_berzerk]

The concept is obviously sound so why is it not done to help the astronauts with muscle atrophy?

You would need to redesign it. Here is a concept drawing by Werner von Braun from 1952, the guy who basically designed our rockets and space program:

View attachment 206357


So it would depend on the radius. Centripetal force (artificial gravity effect) would be v^2/r at a distance r from the center of rotation. So to get 1 g (Earth gravity at sea level) at 100 meters radius, you would have to go about 98 feet per second. That would amount to about 3 rpm. Obviously cost is a factor, plus the fact that up till now, they've been studying the effects of weightlessness, but to go to Mars, there will HAVE TO BE some form of rotating section.

probably be most practical in the sleeping and resting area of the craft

 

[SavannahMann]

It is more than the rotational issue. It is structural strength. Take a thin bit of string, and tie a heavy weight to it. Yes, you can rotate it around you to one G, or even half a g. But the string will break.

The station is designed to operate in microgravity. It is structurally sound in that condition. It would not tolerate any stresses that would produce any amount of gravity. Especially not enough to produce a significant amount, even one third of a G.

To design such a station, you have to start with that in mind. It would mean a lot more mass for stronger materials and such. That would mean more rocket launches, which already cost millions for every time a load of food goes up. Then it would have to be large enough to make the rotation useful. It could not be a spinning thing like on the ground at a fair. That would be too small to be useful.

Then the entire station has to be reinforced to manage the stresses of spinning. Because even a little spin would destroy the existing station.

This is part of a documentary about the Moon Landings. This portion covers the launch of the “Little Joe” rocket that was designed to test the capsule escape system. The towers that would pull the astronauts off the exploding rocket.



It isn’t rotating very fast, but look at the damage that happens. That is exactly what would happen if we tried to start the ISS to spinning for gravity. The rocket in that video is rolling at about the rate that a football does when it is passed. Probably less than that. Yet it was enough to destroy the entire structure. Granted, it was an awesome test, if unintentional, because as the rocket started to explode, the capsule was pulled away safely. Exactly as it was supposed to.

 

[Montrovant]

So you would attach to the outer surface of the spinning object. Just spinning it wouldn't make you gain gravity.....you'd still float if not attached to something to push back against you.

I wore no gravity boots when sticking to the inner wall of a massive spinning barrel as a youth in an amusement park.

I don't see boots being useful.

That was the whole point. Once your velocity matches that of the wall you are pushed against, you will always feel an outward force (actually, it would be a straight line force and you are being turned by the wall). If you were able to push away, or jump away, your momentum would slow (unless you are in a vacuum) and the spin beneath you would continue on. The same effect as the floor spinning past you.

I just remember the ride. For awhile you could move around on the wall quite freely with no support but the faster it went I was eventually plastered solid against the wall and couldn't even lift my hands off of it.

Yeah, that is how they simulate gravity greater than that of Earth. At about 6 or 7g you should be unable to move...at 9g, you'll pass out. Pilots have to deal with those kinds of forces.

I remember the ride you're talking about. You were in a large container like a UFO and it spun and then the floor dropped out and you were held in place.

Was IT the Orbit? Or something like that.

I don't remember the name.

I know it as Gravitron.



I haven't been on one since I was a kid, though.

 

[westwall]

It is more than the rotational issue. It is structural strength. Take a thin bit of string, and tie a heavy weight to it. Yes, you can rotate it around you to one G, or even half a g. But the string will break.

The station is designed to operate in microgravity. It is structurally sound in that condition. It would not tolerate any stresses that would produce any amount of gravity. Especially not enough to produce a significant amount, even one third of a G.

To design such a station, you have to start with that in mind. It would mean a lot more mass for stronger materials and such. That would mean more rocket launches, which already cost millions for every time a load of food goes up. Then it would have to be large enough to make the rotation useful. It could not be a spinning thing like on the ground at a fair. That would be too small to be useful.

Then the entire station has to be reinforced to manage the stresses of spinning. Because even a little spin would destroy the existing station.

This is part of a documentary about the Moon Landings. This portion covers the launch of the “Little Joe” rocket that was designed to test the capsule escape system. The towers that would pull the astronauts off the exploding rocket.



It isn’t rotating very fast, but look at the damage that happens. That is exactly what would happen if we tried to start the ISS to spinning for gravity. The rocket in that video is rolling at about the rate that a football does when it is passed. Probably less than that. Yet it was enough to destroy the entire structure. Granted, it was an awesome test, if unintentional, because as the rocket started to explode, the capsule was pulled away safely. Exactly as it was supposed to.

The rocket broke apart due to aerodynamic stresses. Stresses that don't exist in orbit. I do agree that the ISS cannot be made to spin. It wasn't designed for it. However, if you were to design a space station from the ground up to be able to rotate for gravitational simulation you would not need to add significant mass to it to make it work, and be safe to inhabit.