NASA seeks plutonium alternative to power deep-space missions
JUL 15, 2010
DOI: 10.1063/PT.5.024502
New Scientist : A material used in smoke detectors here on Earth may soon power spacecraft to other planets. The US has long used the decay of plutonium-238 to power its spacecraft to the outer solar system. But because the US stopped producing the isotope in the 1980s, and NASA has almost used up its remaining supply, an alternative fuel is being sought. Americium-241, whose decay is used in smoke detectors to trigger an alarm, may be the solution. Because 241Am decays more slowly than 238Pu, using the new fuel could mean longer trips. On the other hand, 241Am provides less power per unit mass than 238Pu, which would make an americium-powered spacecraft heavier and harder to launch. A solution must be found by 2020, when NASA and the European Space Agency are planning a joint mission to Jupiter.
© 2010 American Institute of Physics
