Engineers preparing NASA’s Curiosity Mars Science Laboratory (MSL) for its planned 2011 launch are taking a closer look at the rover’s radioisotope power system after discovering that the plutonium-powered battery is degrading slightly faster than expected.
Curiosity’s Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is designed to enhance the rover’s range and operability and lifetime on the red planet. The unit uses about 4.8 kilograms of plutonium dioxide, mostly plutonium-238, as a heat source.
“Right now we are working with Department of Energy to try and understand it,” said Doug McCuistion, director of NASA’s Mars Exploration Program, “but to date the only impact is expected to be some operational work-arounds in Martian winter … [a] slower operational pace essentially because it’ll take longer to charge the batteries.”
Curiosity’s MMRTG power plant is fully fueled and stored at the Idaho National Laboratory, where it is awaiting delivery to the rover’s launch site in Cape Canaveral, Fla., next year.
The radioisotope thermoelectric generator oddity is the latest in a host of technological problems that have caused the roughly $2.3 billion mission to a slip its launch two years to October 2011.