English: In the airlock of the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida, Department of Energy employees prepare the support base of the multi-mission radioisotope thermoelectric generator (MMRTG) for NASA's Mars Science Laboratory (MSL) mission for installation of the mesh container, known as the "gorilla cage." The cage, in the background at right, protects the MMRTG during transport and allows any excess heat generated to dissipate into the air. Transport of the MMRTG to the RTG storage facility follows the completion of the MMRTG fit check on the Curiosity rover. The MMRTG will generate the power needed for the mission from the natural decay of plutonium-238, a non-weapons-grade form of the radioisotope. Heat given off by this natural decay will provide constant power through the day and night during all seasons. MSL's components include a car-sized rover, Curiosity, which has 10 science instruments designed to search for signs of life, including methane, and help determine if the gas is from a biological or geological source. Waste heat from the MMRTG will be circulated throughout the rover system to keep instruments, computers, mechanical devices and communications systems within their operating temperature ranges. Launch of MSL aboard a United Launch Alliance Atlas V rocket is targeted for Nov. 25 from Space Launch Complex 41 on Cape Canaveral Air Force Station. For more information, visit http://www.nasa.gov/msl.