Re: It does have a finite life
> However, having a bunch of people floating around for so long isn't neither practical nor acceptable from a health perspective.
But that's also how we learn a) what the health perspectives are, and b) how to mitigate against them for when we *do* decide to leave the planet on a more permanent basis.
A lot of "space health" issues and mitigations are chicken/egg scenarios - you can't simulate the kind of bone density loss induced by extended micro-gravity in a 1g environment. Likewise, solutions to that bone density loss that might work in 1g *really* don't work in micro-gravity - they have to be tested in situ... and a vomit comet isn't a suitable platform to trial an hour-long exercise regime over the months required.
We're going to need to figure those solutions out "on the float", limiting exposure of the individual test subjects to current safe boundaries (and yet always aiming to push those boundaries).
Biting the hand that feeds IT
