Scientists have produced for the first time in three decades a sample of plutonium-238, an isotope which could set the course to provide energy for NASA and other missions.
The Department of Energy of the United States announced on Tuesday it had produced 50 grams of Platonium-238 at the Oak Ridge National Laboratory, which would be the first time that the isotope is produced since 1980, when production at a South Carolina plant stopped.
Plutonium-238 is a radioactive isotope that produces heat as it disintegrates, and can be used in systems that power spacecraft instruments. The new sample is the same oxide power form used for the production of heat sources for power systems.
Researchers will analyze the sample to ensure the plutonium-238 and its chemical purity. Then they will verify that the production process is mostly necessary capacity and determine if adjustments should be made before scaling the process. Once this process is complete, the isotope will be produced in mass.
“Once we automate and scale up the process, the nation will have a long-range capability to produce radioisotope power systems such as those used by NASA for deep space exploration,” said Bob Wham of the ORNL’s Nuclear Security and Isotope Technology Division, according to the Oak Ridge Today journal.
The production of the isotope comes two years after NASA began funding the DOE Office of Nuclear Energy through a roughly $15 million per year effort to revive the department’s capability to make plutonium-238.
When the production begins formally, NASA and the Department of Energy will produce about 300-400 grams of the material per year, and then through automation and extension processes, it will increase to 1.5 kilograms per year.
The Oak Ridge scientists found they could take a mass of neptuinium-237 from the Idaho National Laboratory, mix with its aluminum and press it into high-density pellets. They irradiate those pellets with Oak Ridge’s High Flux Isotope Reactor, blasting it into neputium-238. That substance then decays into plutonium-238.
Wham established that the production of Pu-238 was shown that the process is working, which would lead to the next phase of the mission. The next NASA mission, planning to use a radioisotope thermoelectric generator, is the Mars 2020 rover, due to be launched in July 2020. The mission seeks signs of life on Mars and will test technology for human exploration and gather samples of rocks and soil that could be returned to Earth.
Source: Oak Ridge Today