Post date: Mar 22, 2013 11:11:14 AM
USA. (Next Media) - The United States has resumed production of Plutonium 238 for the purpose of powering NASA’s future deep space missions. The country stopped production of Plutonium 238 in 1988, and had been buying it from Russia, but the Russian supply dried up.
Neptunium 237 can be placed into a fast reactor, and bombarded with neutrons. The product is Plutonium 238, which emits large volumes of alpha particles, but low volumes of other radiation, making it an ideal heat source.In a radioisotope thermoelectric generator, or RTG, Plutonium 238 generates heat, which is harnessed by thermocouple modules to produce electricity sufficient to the power the Mars Curiosity Rover, or the Cassini space probe. RTG’s, such as those used on the Cassini space probe, are much smaller than solar panels, and have no moving parts to break.
Plutonium production will ramp up over the rest of the decade, to one-and-a-half to two kilograms per year. This new Plutonium can be used to revive older stocks, which have decayed beyond usability.
SOURCES:
Universe Today, NASA, Extremetech
http://www.universetoday.com/100875/u-s-to-restart-plutonium-production-for-deep-space-exploration/
http://solarsystem.nasa.gov/rps/rtg.cfm