Astronaut Muscle Deterioration

Scientists find that despite regular and rigorous exercise, inhabitants of the International Space Station have massive muscle loss, both in volume as well as strength. This bodes poorly for a manned Mars mission, which would take 3 years; astronauts returning from that mission would probably suffocate in Earth's gravity upon reentry.

Skipping over my usual diatribe about the ridiculousness of manned spaceflight, and ignoring that robots have been crawling on the surface of Mars quite happily for most of a decade, rendering a Mars mission pointless, let me ask this question: why don't orbital spacecraft spin to create artificial gravity?

Studies suggest even .6 Earth gravity would be enough to maintain healthy bone mass and muscle strength. As early as 1968, centrifugal spacecraft were depicted in film and fiction, including the famous Discovery One of Stanley Kubrick's "2001: A Space Odyssey". Some research has been done on artificial gravity, and most scientists agree the centrifugal method for creating gravity is by far the easiest to design and achieve.

So why, in the last 40 years, have we not built one? "The Coriolis Effect" is not a correct answer.


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