Turning an asteroid into a spinning space habitat
Posted: Wed Dec 21, 2022 7:39 pm
https://newatlas.com/space/space-habitat-ring-plan/To create some gravity, you could hollow a decent-sized asteroid out, potentially, and spin it up like a ring-station, using centrifugal force to create that 0.3g. Then, you could build your city entirely within the spinning asteroid; sure, it'd be dark in there, but the rock would protect people from harmful space radiation. That might have a chance of working if the asteroid was made of solid rock with high tensile strength throughout.
But most asteroids aren't solid rock – at least, not most of the ones in our solar system. The team looked into the composition of our local "flying mountains" and found that most are more or less giant piles of rubble, collections of big and small rocks held together weakly by their own mutual gravity. Hollow one of these things out and spin it up, and the "ground" you're trying to create inside the asteroid would just fling away into space and disappear.
So how could they practically build a human-friendly city on a pile of space rubble? By sticking it in a gigantic bag, they decided. A cylinder-shaped bag a fair bit bigger than the asteroid itself, made from a flexible, ultra-light, ultra-strong carbon nanofiber mesh. This, says lead author and Ph.D candidate Peter Miklavčič, "would be extremely light relative to the mass of the asteroid rubble and the habitat, yet strong enough to hold everything together. Even better, carbon nanotubes are being developed today, with much interest in scaling up their production for use in larger-scale applications.”