The problem isn't health “risk”, there are risks but there are also health effects that will come with certainty. For instance, low gravity deplete your muscles pretty fast. Spend three month in space and you're not going to walk out of the reentry vehicle.
replyThis effect can be somehow overcome by exercising while in space but it's not perfect even with the insane amount of medical monitoring the guys up there receive.
Then just provide spin gravity for the crew habitat.
reply“just”
replyIt's theoretically possible for sure, but we've never done that in practice and it's far from trivial.
Good points. Spin “gravity” is also quite challenging to acclimatize to because it’s not uniform like planetary gravity. Lots of nausea and unintuitive gyroscopic effects when moving. It’s definitely not a “just”
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