When you ask about rotating artificial gravity (yes, yes, technically radial acceleration), most answers boil down to "you'd need a 200m diameter spacecraft, and we can't build that yet"
But, of course, why would you need the entire circle to be a continuous space station? Just tie two modules together with a cable and extend, right?
Are the engineering problems just too difficult and numerous to even consider that? I can see a few already:
- Moving people between the modules, or to a stationary part of the station, would require an EVA. Not only that, but an EVA from a rapidly moving module.
- Making orbital or attitude adjustments would be much more complicated.
- Docking to visiting spacecraft would require a stationary module or stopping the rotation entirely.
- Moving resources between the modules and/or a stationary section would require long cables and pipes, and possibly seals between moving pieces.
Of course, one can think of solutions to all of these. Most can be addressed by temporarily halting the rotation and maybe winching the modules back together. But none of the solutions seem simple. Is it all just too much to even contemplate?
I didn't think I needed to, but I guess I'll clarify the motivation. I've read plenty of people questioning whether Mars gravity (0.38g) is sufficient to ameliorate the many negative effects of long-term weightlessness. It seems reckless to wait until we're there, in the middle of an 18-month mission, to find out.