Americium: How a long-life nuclear fuel will transform space travel

The article discusses the critical role of nuclear power sources, specifically radioisotope thermoelectric generators (RTGs) fueled by plutonium-238, in enabling long-duration space missions like the Voyager spacecraft, which have operated for nearly 50 years in deep space. Plutonium-238’s steady radioactive decay produces heat converted into electricity without moving parts, providing reliable power far from the Sun where solar energy is insufficient. Despite its effectiveness and a half-life of 88 years, plutonium-238 is scarce because it does not occur naturally and must be artificially produced in nuclear reactors, with current production rates unable to meet the growing demands of space exploration. To address this supply limitation, scientists are exploring americium-241 as a promising alternative nuclear fuel. Americium-241, first synthesized during the Manhattan Project, has a much longer half-life of 432 years, potentially enabling power sources that last for centuries rather than decades. This extended longevity could revolutionize deep space missions by supporting spacecraft