Is a Centrifugal Space Station Scientifically Possible ?
I have pondered over this theory for many years and I just don't seem to see how it could work. If you are in 0 gravity and no outside force is influencing you how are you supposed to stick to the wall. Wouldn't you just float in the middle as desks, computers and file cabinets wiz by you that are bolted to the floor. I don't see how Objects moving around me are going to effect my mass. The only thing that would be touching me ( barring a file cabinet doesn't smack you in the head on it's way around ) is the atmosphere inside the station. As far as I know the atmosphere is not affected by the gyroscopic forces created by the spinning station in a way that would make my mas stick to the floor similar to the effects of gravity. What am I not getting here? Why isn't the Centrifugal Space Station like a giant blender? Or do I have a point?
Anonymous2012-07-15T20:11:08Z
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Newton figured out who ti measure and calculate the size of gravity and the motions of objects in a gravity field he also figured out the relation between force and acceleration or change in velocity things can accelerate by changing direction while keeping the same speed nobody knows what gravity "really is" or what causes it einstein showed that we cannot possibly tell the difference between accelerated motion or gravity if we are "inside " a closed container
the big fuss about the "high's Boson" is that it may have something to do with why there is gravity at all. atmosphere has nothing to do with gravity force you are not alone in your confusion in the 1600s nobody believed Galileo or newton either they said. how can the earth be turning? if we jumped it would move out underneath us
The air within the spacestation would start to spin with the station much as coffee swirls when stirred and you wouldn't be free floating as the air would also drag you along causing you to fall to the outside walls. There would be a drift called the Coriolis effect which can be very disorientating but this reduces the larger and slower you make the space station.
There are problems with centrifugal force for space stations, one the structure has to be strong enough to hold 1 g of force all around. The Von Brauhn spacestaion was shown to require so much mass for the strength that it simply wasn't affordable. The Stanford Torus is purposely rounded like a bicycle inner-tube so that the tensile forces in the outer edge was more readily supported. Of course that never sopped people from blogging their versions of the Stanford Torus with a more square edge and claim a more efficient use of space when in fact they've simply made it an unworkable design. The Bernal sphere was proposed to again support the tensile forces by being a sphere. The O'Neill cylinder unfortunately ignores many of the principles of centrifugal force especially in the large tilting mirrors which would of course alter the rotation as they tilted as well as require extraordinary strength against several g's of gravity. The hollow asteroid concept also ignores the fact that it would just fly apart.
The other major problem is that the gravity changes much more rapidly from your feet to your head than on Earth. Indeed, you would have to make a space station, the size of the Earth to have centrifugal force mimic Earth's gravity exactly. It's suspected that rotations of more than 2 rpm would be the tolerable limit, preferably 1 rpm. That would make a diameter of 894 feet preferable in a space station which makes for a very large space station.
You have a point but it's one that's taken into account.
Much shorter answer - the air doesn't stand still, if the room is moving, the air is pushed/pulled along by the walls. If the station was somehow taken into space intact and put in orbit without spinning (rather than being assembled in space from pieces), and then thrusters began it spinning anything loose would "stand still" [that is continue to orbit the earth in the same path as the station] but the walls would eventually move in on the loose junk. Of course, everything bolted down would just move. Since we would expect the walls to be radial to the center in one aspect, anything hitting them from floating would encounter a force "down" the wall - from the point of view of the center of the station all the points on the wall are moving in a curve "up" - like a racquet swung slowly at a ball. Because the air would be affected by the same rotation - where else can it go - a helium balloon that floats in mid air in "zero gravity", would "float" on the slight gradient density and "rise" to the center of rotation.
The centrifugal effect is what provides the outward acceleration that passes for gravity.
Any point on the outer wall of the rotating space station is following the curve of a circle. Any "loose" object moving along with the wall, tries to go in a straight line (Newton's laws). However, the wall of the space spation will force this object to follow the curve of the circle.
In order to get the object to turn in a circle, the wall will have to accelerate the object sideways. To do that, it pushes it towards the centre of curvature. It is this force that is perceived as "weight" by the object or person "standing" on the wall (which will be perceived as a floor).
If this space station is in freefall, in space, then it is true that IF (a big if) an object is placed away from the rotating wall, AND the object is not "playing along" in the movement of the wall, then that object will be in freefall. However, in a "space station" you expect to find air (and walls) so that the object would eventually be entrained in a direction perpendicular to the radius going from the centre of the rotating station to the rotating wall. Air friction pushing on an object may be weak, but if it is the only force present, then it will eventually make the object move.
Of course, if there is a radial wall (from the axis to the outer "floor") turning along with the station, it will eventually hit the object and force it to "play along" in the rotational movement.
Mental exercise: Imagine a cylindrical space station, rotating along the long axis of the cylinder. Somewhere along the axis, is a cabin that is "rotating" (relative to the station) exactly the other way (this cabin is stopped relative to the outside of the station).
Someone in this cabin opens a porthole (looking into the inside of the cylinder), and places a baseball just outside the porthole. This ball is in freefall, so it just floats there (from the point of view of the guy in the central cabin).
For the other guy, standing on the rotating "floor", this ball moves sideways (parallel to the "floor") without dropping... until it hits a wall. Then, in addition to bouncing off the wall, it begins to drop. As it drops (towards the floor) it arcs back towards the same wall. With every bounce, it falls faster and faster. To the guy on the floor, the ball will look as if its gravity was oriented towards the wall (the ball keeps bouncing off the same wall) AND towards the floor.
Once the ball reaches the floor (and participates in the sideways movement of the floor), it no longer appears to have any sideways gravity.
Because our body has mass, the momentum that the spinning of the centrifugal is putting out will cause any thing with mass to be drawn away from it's center causing everything to "stick" to the wall facing opposite. Example. when you are in a car the only think "touching" you is the atmosphere in the car yet your momentum at 50mph is well above 4g, the only way you would fell this is in any significant form would be if the car stopped suddenly. The atmosphere would also be effected by the centrifuge there would have to be a ventilation system in place because the heavier element Nitrogen would start to separate from the slightly lighter oxygen over time.