National Geographic : 1976 Jul
(Continuedfrom page 84) target. Even if we were punctured, air loss would be slow because of the large volume. Air pressure is only half that on earth though there's just as much oxygen," continued Fenton, "but we've cut down the nitrogen to slightly under half the earthly level. Visitors aren't even aware of the difference, except to say that the air is clearer than on earth." Vision of a New Land of Plenty I was walking on a catwalk, and on either side were closely planted tiers (pages 78-9). "This one is our diversified sector," said Fenton. "Here we have vegetables, chickens, goats, as well as rabbit hutches and fish pools. We depend on recycled water, and this sector contains one of our chief cycling stations." He pointed to a windowless metal structure. "You mean-wastes?" "Yes, of course. We retrieve water from organic wastes. What's left is fertilizer. Would you care to go inside?" I shook my head, "Perhaps not." Fenton nodded. "Visitors rarely seem to want to. You understand, don't you, that recycling proceeds on earth too? There it is a larger circle--less noticeable, but more dangerous. We exclude the pathogenic bacteria from L-5, as you must know from your own physical examination be fore you came. Frankly, there is far less odor in the cycling station than in the area with the chickens and goats." "Even so," I said, smiling. "All right. We'll keep on walking. There are plenty of other things to see. The other agricultural sectors have our grainfields: wheat, rice, corn. Under uniform and controlled sunlight, with unfailing water and fertilizer, equable tem perature, and a slightly higher carbon dioxide content in the air, the yields are many times what they are on earth." For the moment, I wasn't listening. We were skirting a long fish pool, and there were small machines moving busily among rows of vegetables. L-5 might be just a pin wheel in space when viewed from outside, but it was a world once one was inside. It was the first of many others that would be larger-and better-and that might someday in the far future (who knows?) bear within their graceful bodies the major portion of mankind's numbers. U Son of L-5, an enormous power station ten kilometers across nears completion behind the spinning torus. The station will be towed into geosynchronous orbit, where it will remain above one point on earth's surface. Its mir rors will concentrate solar heat to drive turbogenerators and produce electricity. Converted to microwaves, the energy will be beamed to earth and reconverted to elec tricity. Eventually, space colonies and power satellites may be as plentiful as milkweed seeds in the wind, and earth's energy crisis a forgotten episode.