[Thnboi666]

so the issue is reduced load on muscles and bones.

10x rate of bone resorption in osteoporosis. bones are the biggest worry imo.

even though the astros work out 15 hours a week, it's still not enough to cover this rate of resorption, and (this is an asspull) pretty sure it affects them for months or years after doing long stays at ISS.

I'm not sure if there's any proof that we could create artificial gravity such that these decreased loads wouldn't still occur. wouldn't it mess with their inner ear as well?

And yeah, the only real issue is cost, but that's a doozy of an issue. what country is going to spent monumental budgets on making this ship with all the financial crises going on currently?

[Grishnakh]

>I'm not sure if there's any proof that we could create artificial gravity such that these decreased loads wouldn't still occur.

Acceleration is acceleration. Your body doesn't care whether it's coming from a big hunk of mass in the form of a planet, or from continuous rotation. Yes, artificial gravity will work just fine in completely eliminating the negative effects of microgravity on humans.

>wouldn't it mess with their inner ear as well?

Only if the diameter of the structure is too small. Then you get coriolis forces large enough to cause these side effects. Effectively, the "gravitational" force felt at your feel is smaller than what you feel at your head. And also, with a small diameter, you have to rotate the structure at a high rate to achieve 1g. With a sufficiently large station, these aren't a problem: the rotation is very slow (maybe 1 rpm) and the difference felt between your head and your feet is negligible. But building a large structure in space like that is difficult and costly and we haven't done it before. But now's a fine time to start....

>what country is going to spent monumental budgets on making this ship with all the financial crises going on currently?

That's the main problem, and it's entirely the fault of the political leadership in those countries, who are mismanaging resources and allowing corruption. George W Bush's Iraq war is a prime example of this: for the cost of that war, we could have built a rather nice space station.

[Neeek]

Wasn't this solved by the vacuum weight set shown on smarter every day? They use a piston in a vacuum with an adjustable pivoting arm to produce consistent resistance (a spring will provide more resistance as it is compressed or stretched than in its rest state). I thought they were saying it was the first time some astronauts were returning home with higher muscle/bone density than when they went up.

[sandworm101]

My GP is big on bones, specializing in old people. He helped develop some of the fancy bone scanners decades ago. He told me that astronaut bone loss is a solved problem, that if they want too they can keep bones strong for a year or more. He was of the opinion that when astros come back with reduced bone it is because they have been part of a study. The goal isn't to save all the bone, but to study exactly how little exercise is needed to achieve satisfactory results.

[Neeek]

That makes sense, easy to forget they are sometimes called on to be highly skilled/paid lab rats at times :)