In 1975, NASA directed a 10-week Summer Faculty Fellowship Program in Engineering Systems Design held at Stanford University. The team worked on the challenge of a point design of how people might permanently sustain life in space on a large scale, and to design a system for the colonization of space. The design supported a population of 10,000 in an Earth-gravity environment; it became know as the Stanford Torus, which is 1.8km in diameter and rotates at 1 RPM.