Perseverance’s Radioisotope Thermoelectric Generator on Mars

NASA's Perseverance Mars rover looks back at its wheel tracks on March 17, 2022, the 381st Martian day, or sol, of the mission. Perseverance carries a Radioisotope Power System, visible on the left of the rover (featuring the large white fins). This power system, known as a Multi-Mission Radioisotope Thermoelectric Generator (or MMRTG), produces a dependable flow of electricity using the heat emitted from the natural radioactive decay of plutonium oxide as its "fuel."