World Ship

Mobile worlds would be enormous space habitats, so large that they might even have some gravity of their own. But rather than the cold metal hulls, the pale electric lights and the generally mechanized environment that we see on so many sci fi movies, these self-contained worlds would hold their own ecosystem inside. Something like a biodome. There would be a main bridge where all the computers, elevator shafts, electric doo-dads, etc would be contained. This would be where such things as navigation, communication, public relations with other mobile worlds, etc would be carried out. But the people would live and play in the biodome sections of these ships. I'm not just talking about something the size of a small park, I'm talking about a fairly large chunk of wilderness. It would be large enough to recycle the CO2 and keep the air freshened for the rest of the ship, feed them, and provide a psychologically refreshing environment. I don't particularily buy the idea that you can seperate people from the natural world and put them in cold metal jungles for long periods of time in space without something going wrong.

The purpose of these worlds would be varried. Some would simply be built for people who favour a particular type of society, government, spiritual philosophy, etc. They might have fairly stationary orbits. Others might serve the purpose of ferrys and move regularily from the outer planets to the inner planets as public transportation. Some would ship raw materials from different parts of the solar system to establish commerce. Some would have extremely elaborate ecosoytems and be used for tourism.

In these low-gravity environments, trees and grasses would grow impossibly high and in all types of strange shapes and labyrinths. If gravity is simulated by spinning the spacecraft, it would most likely have a cylindrical shape. The inner wall of the cylinder would be the ground. People on the inside of this world could look "up" and see a sky filled with more forests. Water would conform to the shape of the ground and you could watch the strange spectacle of people paddling a canoe across concave lakes. There would be all kinds of berries, mosses, fruits, colorful fungi, grassy glades, flower-bearing trees and pollenating insects. Percipitation would have to be in the form of mist, so air currents and heat regulation would have to be controlled to ensure adequete watering of the whole ecosystem. Night and day would be simulated, bringing out night-blooming flowers, biolumenescent organisms like fireflies and foxfire. In the weak gravity, people could climb the trees and stand on incredibly thin branches near the treetops. They would be more like springy trampolines and people could jump across the top of the canopy. The tourist attraction of this type of world would be huge.

The outsides of these worlds would be as varied as their purposes. Ones near the sun would use magnetic bubbles to navigate within the solar wind. Their surfaces would be glassy and filled with a jacket of water to keep out harmful radiation while letting in the proper types of light for plant growth. They would mine the solar wind for fuel that would be shipped out to other worlds where solar power is too feeble a source of energy. Others might set up massive generators consisting of conductive tethers that cut through the flux-lines of planets and are anchored at both ends by efficient ion rockets that keep the tethers spinning. The electricity would be converted to a laser and beamed to energy collectors located on the outer hull worlds that orbit planets like jupiter or saturn.

Other worlds could exist in the Oort Cloud where ice has the consistancy of solid rock. Comets could be stripped down for their raw materials and the ice could be used for the outer hull of the ship. An insulating layer of material would line this inner wall of ice to protect it from the heat of the habitat, and vice versa. Such an environment would be favourable to an electrical system that uses superconductivity, seeing as this part of space would approach absolute zero. Its energy would depend almost entirely on shipments of fuel from the inner solar system, but it would provide its own type of resource in the form of science. These worlds would bring back information from the deepest reaches of space and be the first to set out for the stars. The unique, frigid environment they inhabit would also be a perfect environment for scientific experiments that are not feasible to conduct otherwise. And they would also contain ecosystems. Even out beyond the orbit of Pluto, worlds could contain tropical jungles inside themselves.

All in all, orbital worlds would change space exploration into a process rather than a product. Instead of setting out in small ships for several months in order to reach planets upon which to settle, people would colonize space itself. Rather than going to Mars, where lots and lots of technology needs to be shipped from Earth before the colony becomes self-sustaining and able to produce a return in order to pay for itself, orbital worlds can start production fairly quickly and be a place of continued population growth, culture development, arts and crafts, scientific research, builders of space infrastructure, etc. Moving out to settle the planets would not require any particular effort when most of the infrastructure already exists in space. One of these worlds could travel out to Mars, drop off colonists and stay in orbit untill the colonizers get on their feet. Then it could go off to a completely different destination. That way you haven't created some mega spacecraft just for one particular mission. Meanwhile there is no particular urgency to the colonization of a new home, because the world-ships will be homes in their own right.