"Space colonies are now being considered seriously by some people. The one in the picture [above] is controlled throughout by a big central computer. The colony is positioned 240,000 miles (350,000km) from Earth and about the same distance from the Moon. It consists of a great tube 430 feet (130m) across. This tube forms a ring over a mile in diameter. The tube houses the main living and agricultural areas and can support up to 10,000 people. The big wheel rotates once a minute. This makes an artificial gravity on the surface of the tube away from the center. "Up" is towards the hub and "down is away from it."
"Sunlight is reflected from huge mirrors that can be adjusted to give as much or as little sunlight as required in different parts of the tube. The sunlight also gives the energy to drive the generators which produce the colony's electricity. Long "spokes" attach the tube to a central hub. At the hub there are docking ports for spaceships and vast antenna arrays for all the colony's communications with Earth."
Checkerboard Press, (1989), "Checkerboard Press Computers and Electronics"