This computer-generated close up of the TransHab Module crew quarters is an example of the living space available in such a module.

One of the earliest designs for living in space was clearly a fantasy: an orbiting sphere, 200 feet (61 meters) in diameter, made of 12 million bricks and housing thirty-seven human inhabitants determined to create an ideal society. It was described by Boston religious leader Edward Everett Hale in a short story titled "The Brick Moon" in Atlantic Monthly magazine in 1869. It was written as a fable, never meant to be taken seriously. Later, Russian mathematician Konstantin Tsiolkovsky, after seeing France's Eiffel Tower in 1895, was at first obsessed with the idea of building a tower 35,786 kilometers (22,300 miles) into the sky. In his 1920 novel, Beyond the Planet Earth, a more mature Tsiolkovsky proposed a geosynchronous orbiting space station, with an international crew, greenhouses, and solar power—a remarkable vision very...