Stanford Torus

Summarized from wikipedia published under the Attribution Share-Alike 4.0 Creative Commons license.

The Stanford Torus is a space habitat capable of housing 10,000 to 140,000 permanent residents. The Stanford torus is a ring-shaped rotating space station, previously proposed by Wernher von Braun and Herman Potočnik in the 20th century then elaborated in the 1975 NASA Summer Study which was held at Stanford, hence the name.

Torus The Stanford Torus consists of a doughnut-shaped ring 1.8+ km in diameter that rotates once per minute to provide between 0.9 g and 1.0 g of artificial gravity on the inside of the outer ring via centrifugal force. Larger rings spinning a bit slower (so they are still 0.9 - 1.0 G) handle larger populations.

Mirrors Sunlight is provided to the interior by a system of mirrors reflecting the local sunlight. The ring is connected to a hub via spokes, which serve as conduits for people and materials traveling to and from the hub.

Hub Zero-G industry is performed in the non-rotating hub and spacecraft dock there.

The interior space of the torus itself is used as living space, and is large enough that a "natural" environment can be simulated; the torus appears similar to a long, narrow, straight glacial valley whose ends curve upward and eventually meet overhead to form a complete circle. The population density is similar to a dense suburb, with part of the ring dedicated to agriculture and part to housing.

Construction The torus requires nearly 10 million tons of mass. Construction would use materials extracted from the Moon and sent to space using a mass driver. A mass catcher at L2 would collect the materials, transporting them to L5 where they could be processed in an industrial facility to construct the torus. Only materials that could not be obtained from the Moon would have to be imported from Earth. Asteroid mining is an alternative source of materials.[9]

General characteristics

Proposed Location: Earth–Moon L5 Lagrangian point (Traveller proposals would be in many systems).

Total mass: 10 million tons (including radiation shield (95%), habitat, and atmosphere)

Diameter: 1,790 m (1.11 mi)

Circumference: 5,623.45 m (3.49 mi)

Habitation tube diameter: 130 m (430 ft)

Spokes: 6 spokes of 15 m (49 ft) diameter

Rotation: 1 revolution per minute

Radiation shield: 1.7 meters (5.6 feet) thick raw lunar soil