X-10 Graphite Reactor

The X-10 Graphite Reactor at Oak Ridge National Laboratory was built during the Second World War as part of the Manhattan Project to bridge the gap between experimental success and large-scale plutonium production. The world’s second artificial nuclear reactor and the first designed for continuous operation, it served as a semiworks facility where methods were tested, procedures refined, and staff trained for later work at Hanford. After going critical in 1943 and producing plutonium in early 1944, it supplied Los Alamos with important material and helped reveal why an implosion bomb design was needed. In 1945 it shifted to research and isotope production, and in 1948 it became the first nuclear reactor to produce electricity.

Oak Ridge, Tennessee · United States