Artwork of a view through a Stanford Torus, during a simulation of night time. This is a design for a space station proposed by NASA in 1975 at Stanford University. It consists of a torus with a radius of 1800km and a cross-sectional radius of 130m for the habitable section. The ring is connected to a central hub via a series of six spokes, which also allow transport from the hub to the habitable section. Rotating at one revolution a minute the station provides an artificial gravity equivalent to roughly 0.9 Earth gravities, and can house around 10, 000 to 40, 000 people. The station would be constructed at the Earth-Moon L5 Lagrangian point - that is, sharing the Moon's orbit but being 60 degrees behind it in phase.