With only a handful of people actually in space right now, one of their primary functions is to be guinea pigs for the long-term effects of microgravity. Absolu

With only a handful of people actually in space right now, one of their primary functions is to be guinea pigs for the long-term effects of microgravity. Absolutely nothing about that is true for the case of a station with 100 people engaged in regular operations. You don't have to have a centrifuge for 100 people, one with capacity for 20 people, cycling the people in and out in rotation is probably sufficient. The wheel radius can be kept quite small, because nausea scales with the amount of movement the people in the wheel have. Easy solution - just don't have them move while in the wheel. This is still unknown territory, but already we have made significant progress developing routines that reduce bone decalcification on the ISS, and that's with pure microgravity. Talking about the first orbiting station with 100 or 1,000 people.. these will not be comfortable places. They will be extremely poor destinations for a relaxing vacation. But people should be able to work there sustainably, in rotations, as part of their careers. It's still allowable to call those places towns in the same way people call aircraft carriers cities today.