# rotating space station

Rotating space station and artificial gravity

Quote:

I think we can appeal to simple angular momentum (AM) conservation. AM is mass x spin radius x spin velocity. When standing on the inside surface of what I presume is a spherically shaped vehicle, your AM is proportional to your distance from the center of spin (the sphere’s center). When you jump up, you decrease that distance, and therefore increase your spin velocity relative to the rotating “ground”. Thus, you develop a deflection in the direction of spin.

On Earth, you leap upwards away from the center, ostensibly yielding a “backward” displacement. But reason why this won’t happen (measurably, anyway) on a rotating Earth is that your vertical leap would have to be nonnegligible relative to the Earth’s radius. Otherwise, you could jump real high and wind up somewhere nicer, like Hawaii (if you’re not there already)

Actually, in freefall, the artificial gravity is created against the walls of the “spokes” not the outer rim. Centrifugal force stems from an object first being effected by gravity then "sticking " to the outer walls of say a spinning slingshot.

I wish I had the book on hand so that I culd reference the title, but I have a psychology/physiology (the author feels that the two are so strongly interconnected that one cannot really study psychology without looking at how the body affects it) book at home that mentions at least three different ways to realize that you’re in a rotating space station within one of their anecdotes, all of which seem rational. They have the one about jumping straight up. They also say that dispalcing yourself in the Z-direction rapidly (therein done by the abductee jumping off of a table) can result in your head being at a significantly different gravity than your feet if you’re close enough to the hub. Lastly, and perhaps most practically, the protagonist notices that all of the dust is collect on one side of the walls, the side that is rotating towards him.

parady has a correct explanation of the Coriolis effect, but unfortunately, I’ve noticed that terms like “angular momentum” tend to make the eyes of non-physicists glaze over. Sooner or later, I’ll be working on another Report to try to put it in non-glazing terms… Wish me luck.

jimpatro, you’ll only stick to the walls of the spokes if the rate of the station’s rotation is constantly increasing. This isn’t very practical for a space station, since you’ll pretty quickly get up to ludicrous speeds. However, the “artificial gravity” which keeps your feet stuck on the rim works just fine, even if the rate of rotation is constant. Centrifugal force in no way depends on an object being first affected by gravity.

SeanDuggan, as for that dust, it’ll only tend to settle on the wall coming towards you if the dust has a net tendancy to move downwards (if, say, it’s mostly produced near the “top” (center) of the space station, and spreads from there). If the dust is produced near the “floor”, then it’ll settle mostly on the other wall, and if it’s produced throughout the room, it’ll settle on all walls equally.