What a joke. Our space program is shameful.

[Ultima]

Originally posted by: silverpig
AFAIK, bone loss in space occurs because, well, we don't really need bones in space. It's sort of like how you'll get fat, weak and lose muscle mass if you lay in bed constantly, and the opposite of how you get large strong muscles by working out. Your body just adapts itself to it's environment. If you do a lot of hard manual labour all day long, your body will compensate to make the work easier by spending more of it's resources on muscle development. If you sit on your ass all day, there's no reason for your body to have any muscles, so it doesn't develop them.

It's the same in space and on earth. On earth, you have to support your own weight, and you need bones to do that. If we all lived on Jupiter (gravity > 2g), we'd have extremely strong bones. In orbit, you don't have to support your own weight very much, so all of the superfluous calcium is done away with. (note: it's not because of the lack of gravity at all; there is gravity in orbit, and actually, it's not that much weaker than the gravity we feel here on the surface. If you were in orbit, but were constantly being pulled down magnetically or by elastics, you'd lose less bone mass. In fact, astronauts do exercises that simulate surface-like gravitational effects.)

Yes there is gravity, but it isn't felt because you're in a freefall. There's gravity on earth too but you can temporarily become weightless by skydiving until the aerodynamic resistance slows your fall. I think that they have a jet that goes really high then screams toward the earth to induce weightlessness for 30 seconds or so.

 

[silverpig]

Yeah... what I said...