With just little plutonium-238 left for NASA’s three batteries to power deep-space missions, US is reopening its nuclear reactors to meet the demand.
The US Department of Energy said 50 grams of the substance has been made at the Oak Ridge National Laboratory (ORNL) in Tennessee, first time in three decades that the material has been made within the country. The DOE’s Office of Nuclear Energy develops, manufactures, tests and delivers radioisotope power systems for space exploration and national security missions.
The production of 50 grams of plutonium-238 –roughly the mass of a golf ball – marks the first since the Savannah River Plant in South Carolina ceased production in the late 1980s. NASA’s Mars program requires at least 4 kilograms of Plutonium-238, and DoE plans to produce 1.5 kg in the next three years ahead of the Mars mission 2020.
Plutonium-238 is already in use for space missions Voyager, Curiosity, and New Horizons and the material is essential for deep space journey planned for Mars in the future missions to be powered by Multi-Mission Radioisotope Thermoelectric Generators (MMRTGs).
“This significant achievement by our teammates at DOE signals a new renaissance in the exploration of our solar system,” John Grunsfeld, associate administrator for NASA. “Radioisotope power systems are a key tool to power the next generation of planetary orbiters, landers and rovers in our quest to unravel the mysteries of the universe.”
The highly radioactive plutonium-238 decays into uranium-234 and gives out immense heat to be converted to electrical energy by radioisotope thermoelectric generators to keep scientific instruments warm in the cold void of space. So far, 27 US space missions have used this radioisotope power for their electricity and heat. NASA said it has 35 kg of plutonium-238, of which 17 kg is for spacecrafts.
Essentially a nuclear battery, an MMRTG can provide about 110 watts of electrical power to a spacecraft and keeps warm its science instruments. Even NASA’s Curiosity Mars rover, now deep into its third Earth year seeking signs of habitable conditions on the Red Planet is using MMRTG for its energy.