Thanks for the math, Swampyankee, I was wondering about it myself. As for the smallest rotating habs, the research I've done suggests 3 RPMs is a maximum, which is what I use for simplicity and utilitie's sake (1g=100m radius). Since I wanted to minimize the mass, e.g. shielding, of the craft I was planning on using for interplanetary travel (a mars-earth cycler trajectory) had decided to use 3 RPM and max it out near Mars Equivalent gravity (~.37g = 37m radius), although there would be one more "downward" rotating deck used for engineering space. After determining the mission scale and population density, I arrived at a deck width (cylinder axial length) of about 20m, increasing in width towards the axis (I thought this might help maintain balance if it had a triangular cross-section (sideview)). Outside of this are several non-rotating envelopes, one for water (outward of the habitat deck width only), two for air at lower but still substantial pressure and then a vacuum envelope inside a mass shielding envelope. Each of these envelopes has about 1.5m of crawlspace (floatspace) between them to allow for manned maintenance, and they also act as a bit of a Whipple shield in the event of an impact, while the shield mass, air mass (and water mass) and envelope geometry might help alleviate bremsstrahlung.
Well, it might be better to send it to Mercury for processing, or anywhere sunward of Earth if you can't process it in situ and then send finished products or refined material in bulk to Earthspace.
Originally Posted by Philippe Lemay
Et tu BAUT? Quantum mutatus ab illo.