Generation ship

A generation ship is a hypothetical type of starship that would travel much slower than light across great distances between stars (see interstellar travel). Since such a ship might take thousands or tens of thousands of years to reach even nearby stars, the original occupants would die during the journey, leaving their descendants to continue traveling.

Related Topics:
Starship - Light - Interstellar travel

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It is estimated that, in order to assure genetic diversity during a centuries-long trip, any generation starship would require at least 500 inhabitants (though this could also be achieved for a much smaller crew through the use of sperm banks or egg banks brought along for the journey). Additionally, the ship would have to be almost entirely self-sustaining (see Biosphere, life support) so as to provide food, air, and water for everyone on board. It must also have extraordinarily reliable systems that would not fail even over long periods of time, or alternately that could be repaired by the ship's inhabitants if they did.

Related Topics:
Genetic diversity - Sperm bank - Egg bank - Biosphere - Life support

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People have advocated that before humans send generation ships to the stars, we should create large self-sustaining space habitats first. Each space habitat would be isolated from the rest of humanity for a century, but near enough to Earth for help. This would test if thousands of humans can survive a century on their own before sending them beyond the reach of any help.

Related Topics:
Space habitat - Earth

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Generation ships are often found in science fiction stories. A common theme is that inhabitants of a generation ship have forgotten that they are on a ship at all, and believe their ship to be the entire universe. Famous examples of this include Brian Aldiss's novel Non-stop, Robert A. Heinlein's novella Orphans of the Sky, Gene Wolfe's four-novel series Book of the Long Sun, the early 1970s TV series The Starlost, the novel Colony by Rob Grant, the Original Animated Video Megazone 23, Arthur C. Clarke's/Gentry Lee's 'Rama' series of books, and the Star Trek episode "For the World is Hollow and I Have Touched the Sky".

Related Topics:
Science fiction - Theme - Brian Aldiss - Robert A. Heinlein - Orphans of the Sky - Gene Wolfe - Book of the Long Sun - 1970s - The Starlost - Rob Grant - Original Animated Video - Star Trek - For the World is Hollow and I Have Touched the Sky

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A book in which a Sleeper ship goes wrong and becomes a generation ship was written by James White. This book also has a vastly different type of generation ship, a ship that was sunk during WW2, with living people still on board. That ship did not completely sink, but lodged itself on a reef. It is completely submerged, but within pressures that its hull can resist.

Related Topics:
Sleeper ship - James White

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Some have compared planets with life to generation ships; this idea is usually called "Spaceship Earth".

Related Topics:
Planet - Spaceship Earth

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