关于这张图
Jet Propulsion Laboratory (JPL) employees bolt a radioisotope thermoelectric generator (RTG) onto the Cassini spacecraft, at left, while other JPL workers, at right, operate the installation cart on a raised platform in the Payload Hazardous Servicing Facility (PHSF). Cassini will be outfitted with three RTGs. The power units are undergoing mechanical and electrical verification tests in the PHSF. The RTGs will provide electrical power to Cassini on its 6.7-year trip to the Saturnian system and during its four-year mission at Saturn. RTGs use heat from the natural decay of plutonium to …