metanautics:

Imagine a city in space, a round structure miles across that millions of people would call home. Engineers working at NASA in the 1970s developed colorful proposals for permanent settlements in space, but their plans were shelved and forgotten. Decades later, a new generation of dreamers from high schools around the world aspire to mine asteroids, terraform other planets, and venture to the stars. The students have come together for a contest at NASA, and have big plans for the next millennium.

Someday Somewhere Beyond by Jonathan Minard