>>11564615>For smaller asteroids that aren't rubble pilesWe've never found any asteroids that aren't rubble piles. Even comets appear to be loosely fused boulders of ice and rock grains, and covered in layers of dust which form while the object is in that magical zone were it's warm enough for ice to sublimate but not so warm that the rate of sublimation causes the dust to be blown away.
We will never, NEVER, have stations attached to asteroids that spin to produce gravity. First of all, you need a very remarkably monolithic asteroid to make that even possible without it tearing apart, secondly even the best candidate asteroids will invariably be coated in millions of tons of loose rock at least, which will fly off into huge dust and debris clouds once spun up, and thirdly even a completely monolithic asteroid, literally just one big rock, even if it had no cracks, would not be able to withstand the force of being spun fast enough for the attached station to experience 1 g, because rock's tensile strength is too weak.
Stations won't have any problem with holding propellant, in fact there's no real reason why a large space station couldn't have as much delta V as a good chemical rocket stage, simply because if we have the technology to build 200 m wide or greater rings/cylinders as pressurized habitats, we can do the same thing and fill those volumes with propellant instead. Big well-shielded spinning habitats could approach mass ratios of 90% or even 95% propellant, simply because of the square-cube law. They may have slow accelerations, sure, but if you're literally moving your entire city with you and all your farms, you've got time. Fuck it, fly all the way out to Neptune and claim Triton for your own, and use its ices and minerals to make more habitat ships, why not?
