It is a centrifuge in which the individual enclosed capsules, each of which hold 4 people, are on the periphery of a circle facing the center of the circle. the circle spins at a terrific rate of speed generating G forces on the body. Because you are in an enclosed capsule you do not see that you are spinning at all you only feel the pressure forcing you into the seat. You are advised to look straight forward at the screen which represents the window looking out of your capsule, so that you see the sky and space approaching as you take off.
I think it is not so much the spinning itself as it is the G force that affects many people, at least in my case. It caused my blood pressure to rise to dangerous levels and almost caused me to black out. I know I should not have ridden it at all, but as so many others here, I figured it was as close to going into space as I would ever get and I had to try it once.
I am glad I did but If I had it to try once over again, knowing what I know now I would not do it.
Anyway it does not really compare with any other ride in the industry currently.