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SP-100

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated August 19, 2026
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SP-100 (Space reactor Prototype) was a U.S. research program for nuclear fission reactors usable as small fission power systems for spacecraft. It was started in 1983 by NASA, the US Department of Energy and other agencies.

A reactor was developed with heat pipes transporting the heat to thermoelectric generators which would generate 100 kilowatts of electric power, thus the name SP-100. It was cooled with lithium. The project never advanced to flight hardware and was terminated in 1994.

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This article is adapted from the Wikipedia article “SP-100”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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