> Do we have any idea IIRC, largely no - it's a very open research question. > I'd really like to know I fuzzily recall seeing an applicable NASA space medic

> Do we have any idea IIRC, largely no - it's a very open research question. > I'd really like to know I fuzzily recall seeing an applicable NASA space medicine slide deck last year, but I'm not quickly finding it - sorry. > depend on whether Mars has enough gravity While it's common to oversimplify and exaggerate minimum-size constraints on rotational gravity, even if greater than Mars gravity is needed almost continuously, it might perhaps turn out easier engineering to maintain that on Mars (with mounted spinning things, or maybe pods in curving tunnels) than in space (spinning habitats). You still have vacuum at hand, but also support and workspace - things are more easily stopped, stood next to, and kicked.