Design Monologue 10: The Reality of Colonization: Lessons from Cowboy Bebop
Making every world in the DMZ a dusty, Wild-West-like desert risks more than just ripping off Firefly.
It doesn't make sense.
There are only two basic types of colony: homestead and industrial operations.
In the former case, individuals looking for a better life would seek out nice, friendly, Earth-like worlds, and settle the most favorable biomes of those worlds.
In the latter, corporations looking to mine or manufacture in systems where laws are loose would set up operations as near to the necessary raw materials as possible. These types of colonies would often be self-contained factory-cities, built on totally uninhabitable worlds. Essentially, such installations are space stations that happen to be on a planet or moon.
Of course, a civilization advanced enough for terraforming can probably handle a smaller project: making an enclosed city as Earth-like as possible, despite the inhospitable world outside it. And this is how most of these factory-cities are; to varying degrees, per the impetus of the corporation who built it, these installations are like slices of Earth life, built entirely around a massive resource-gathering operation.
Those not lucky enough to happen upon an already Earth-like world, complete with soil and a rich array of flora and fauna fit for human consumption and use, must shell out big bucks to make their worlds livable. Few can truly afford such things, so they typically end up shipping out to some factory-city, where there is work to be had, albeit low-paying and unsafe at times.
Only those with the means, either themselves or in a large co-op, to truly outfit a homestead with the proper terraforming equipment, can establish an Earth-like existence on an alien world.
Typically, the process begins by seeding candidate worlds with algae, to begin modifying the oxygen content of the atmosphere, and sometimes self-replicating nanomachines, to reshape the very structure of the planet's crust. In some unusual cases, ice locked away in glaciers or underground may be freed with explosives.
The process takes, at best, years; some planets take more than a lifetime. Many just fail outright.
Those with the wherewithal and patience to terraform their own world are, by convention, the owners and sole governors of that world. It becomes an independent state, with whatever laws they care to draft. Of course, such states would be highly vulnerable to those who would steal such a treasure, so often these colonies opt to join a larger government of some kind for mutual protection.
The Foundation has immense resources, and are always in the process of terraforming several hundred new worlds. The resources needed to terraform are thus already under high demand, making it that much more difficult for modern homesteaders to get their hands on some. Most of the worlds in the DMZ have long since been terraformed, but many are only partially complete, and some are degrading and in need of maintenance.
And that's one way to get the desert-and-mud worlds of Firefly, by focusing entirely on the poorly-terraformed worlds, the ones with flaws. However, that isn't entirely necessary, as this setting isn't trying so hard to evoke the Western feel.
Rather, like Cowboy Bebop, much action occurs on small moon colonies. The corporations who own these colonies have many things to do, and many enemies who'd like to see them fail. Most importantly, they have a lot of money, and are in need of independent contractors. The same logic applies to their many space stations. These are the places most find work in the DMZ, not the homesteads.