What have we learned from sci-fi? (part 4)

Colonizing other worlds seems like the thing to do. A common trope in sci-fi stories is the need for humankind to leave Earth and colonize other planets. There are various reasons given for this expansion of the human race—Earth is overpopulated, the planet is dying, we've used up all the resources available, we've over-polluted, or we've nuked ourselves to oblivion and most of the planet is irradiated. In many sci-fi stories, migrating to another planet often involves “terra-forming,” a process that converts the new planet into something similar to Earth. Perhaps the new planet's atmosphere is unbreathable, or maybe there isn't any water present. Movies like Red Planet, Total Recall (1990 version), Aliens, or Battle for Terra all involve the process of terra-forming. Sometimes colonies are established only to mine a moon or planet and collect a particular resource—this has even gone as far as establishing a small outpost on a roaming asteroid just to extract valuable ore from its composition. In reality, these endeavors are all likely, once we have the technology and can profit from such efforts. By contrast, privately-funded pioneers are looking to establish colonies with simpler incentives—the pure adventure and challenge alone has driven those with an eye to the stars.