Almost two billion years ago a series of self-sustaining nuclear fission "reactors" self-assembled in the area now known as Oklo in Gabon, West Africa. The conditions at that place and time allowed a natural nuclear fission to occur with circumstances that are similar to the conditions in a constructed nuclear reactor.Video of physics lecture – at Google Video; a natural nuclear reactor is mentioned at 42:40 mins into the video Fifteen fossil natural fission reactors have so far been found in three separate ore deposits at the Oklo uranium mine in Gabon. First discovered in 1972 by French physicist Francis Perrin, they are collectively known as the Oklo Fossil Reactors. Self-sustaining nuclear fission reactions took place in these reactors approximately 1.5 billion years ago, and ran for a few hundred thousand years, averaging 100 kW of power output during that time.Meshik, Alex P. (November 2005) "The Workings of an Ancient Nuclear Reactor." Scientific American. p. 82. The concept of a natural nuclear reactor was theorized as early as 1956 by Paul Kuroda at the University of Arkansas.
Almost two billion years ago a series of self-sustaining nuclear fission "reactors" self-assembled in the area now known as Oklo in Gabon West Africa The conditions at that place and time allowed a natural nuclear fission to occur with circumstances that are similar to the conditions in a constructed nuclear reactorVideo of physics lecture – at Google Video; a natural nuclear reactor is mentioned at 4240 mins into the video Fifteen fossil natural fission reactors have so far been found in three separate ore deposits at the Oklo uranium mine in Gabon First discovered in 1972 by French physicist Francis Perrin they are collectively known as the Oklo Fossil Reactors Self-sustaining nuclear fission reactions took place in these reactors approximately 15 billion years ago and ran for a few hundred thousand years averaging 100 kW of power output during that timeMeshik Alex P (November 2005) "The Workings of an Ancient Nuclear Reactor" Scientific American p 82 The concept of a natural nuclear reactor was theorized as early as 1956 by Paul Kuroda at the University of Arkansas