The shuttle to Mars

Not as many studies in these areas as we might have liked. But this much is true: Once weve established a firm limit on RPMs, 1/20th of a G could be had for 1/20th of the radius length, vastly reducing the structural requirements.

But if the Globus/Stout paper is correct, we might be more apt to reduce the structural requirements by moving to higher RPMs than by compromising on the amount of gravity generated.

For a Mars-bound spacecraft, Id like to see a system where the rotation rate could be varied as you go. This could be accomplished without expending reaction mass if you had 2 counter-rotating sections. Start out at 1-G, and then slowly transition to 1/3 G during the months of the outward trip. By the time your astronauts were ready to land on Mars they would already be acclimatized to 1/3 G and there would be no initial awkwardness associated with moving around on the surface. Then on the return leg, you steadily transition from 1/3 to 1 G. Then when your astronauts are at Earth, there would be no need for a rehabilitation period before they would be good for moving around on Earth.

But coming back to your point, like you, I suspect even very small amounts of centrifugal force might be an advantage over 0-G, even if not enough to help with muscles and bones. If nothing else, it would be handy to be able to place objects on surfaces and still have them be there when you come back. Perhaps a more normal type of toilet would be possible. Its an interesting question how low a level of G would be enough to enable a sense of up and down. That might make things easier too.

Regards,
Mike Combs

From: spacesettlers@yahoogroups.com [mailto:spacesettlers@yahoogroups.com]
Sent: Sunday, May 12, 2019 10:30 PM
To: spacesettlers@yahoogroups.com
Subject: [EXTERNAL] [spacesettlers] : The shuttle to Mars

In 'The Martian' movie the shuttle to Mars is a rotating spacecraft.
https://www.youtube.com/watch?v=ZBowoAJGvDM

Has any study been done to evaluate a zero g shuttle against a shuttle which provides let us say 1/20 g. An astronaut having mass of 60 Kg would experience a force of 3 Kgf.

A small rotation would keep things in place and might aid an astronaut's sense of balance and hence his/her health and well being.

Regards,
Selvaraj

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