A Bernal sphere is a type of space habitat intended as a long-term home for permanent residents, first proposed in 1929 by Dr. John Desmond Bernal. Artists conception of a space habitat called the Stanford torus Space colonization, also called space settlement and space humanization, is the hypothetical permanent autonomous (self-sufficient) human habitation of locations outside Earth. ... 1929 was a common year starting on Tuesday (link will take you to calendar). ... John Desmond Bernal (1901-1971) was an Irish-born scientist (from Nenagh, County Tipperary), known as a scientist who pioneered X-ray crystallography, and also as a communist activist. ...

Dr. Bernal's original proposal described a hollow spherical shell 16 km in diameter, with a target population of 20,000 to 30,000 people. The Bernal sphere would be filled with air. This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

In a series of studies held at Stanford University in 1975 and 1976 with the purpose of speculating on designs for future space colonies, Dr. Gerard Kitchen O'Neill proposed a modified Bernal sphere with a diameter of only 500 m rotating at 1.9 RPM to produce a full Earth gravity at the sphere's equator. The result would be an interior landscape that would resemble a large valley running all the way around the equator of the sphere. Sunlight was to be provided to the interior of the sphere using external mirrors to direct it in through large windows near the poles. The form of a sphere was chosen for its optimum ability to contain air pressure and its optimum mass-efficiency at providing radiation shielding. For other meanings of Stanford, see Stanford (disambiguation). ... 1975 was a common year starting on Wednesday (the link is to a full 1975 calendar). ... 1976 is a leap year starting on Thursday (link will take you to calendar). ... Gerard Kitchen ONeill (1927 - 1992) was a U.S. physicist and space pioneer. ... Earth, also known as the Earth or Terra, is the third planet outward from the Sun. ... Gravitation is the tendency of masses to move toward each other. ... The equator is an imaginary line drawn around a planet, halfway between the poles. ... A mirror is a reflective surface that is smooth enough to form an image. ... Pressure is the application of force to a surface, and the concentration of that force in a given area. ... Radiation generally means the transmission of waves, objects or information from a source into a surrounding medium or destination. ...

This version of the Bernal sphere was dubbed the "Island One" design, and was sized for a population of 10,000. For comparison, Island Two would house 140,000, and Island Three (O'Neill cylinder) would support a population of 10,000,000. A pair of ONeill cylinders The ONeill cylinder is a space habitat design proposed by Gerard K. ONeill in his book The High Frontier. ...

External links

• L5 News: Bernal Sphere Details (http://www.l5news.org/bernalspheredetail.htm)
• NASA SP-413: Space Settlements - A Design Study. (http://www.nas.nasa.gov/Services/Education/SpaceSettlement/75SummerStudy/Table_of_Contents1.html)
• Images from Google (http://images.google.com/images?q=Bernal+sphere)