Kevin Kelly’s Technium Blog is consistently mind blowing. If you are not reading it yet, you should. In one of his recent posts he linked to this amazing USA Today slide show that illustrates the evolution of the International Space Station:
For one, it’s amazing to see how macro scale modular design really looks like. Modularity is a good thing – this sort of became an engineering mantra. In our daily lives we see it in much smaller scales – computer parts, automobile parts, etc… We don’t often see human habitats built this way.
Most importantly though this suggests how space stations will be built in the future. They will start small, and then slowly grow over time as new modules are added and old ones are replaced. Kevin Kelly suggests that they will grow like modern cities – always expanding, changing and re-shaping their structures. Old, mature stations will be almost labyrinthine networks of new and old modules.
Compare that to the almost canonical monolithic rotating wheel station you can see in most science fiction works. These stations are vastly expensive mega-structures which have to be built in one piece. The wheel can’t really be modularized – once it’s complete you can’t really add to it. You could potentially add more wheels to the spoke, but each one of them would be ass expensive as the first.
The current model of modular, slowly evolving floating city is much more practical, and affordable. Of course without the wheel we can’t have artificial gravity. Still, we are talking about science fiction here. I would think that inhabitants of gigantic modular space hives will likely be geengeneered to survive in zero-g without the usual side effects that plague astronauts today.