(07/18/1997) --- Carrying a neutron radiation detector, Fred Sanders (at center), a health physicist with the Jet Propulsion Laboratory (JPL), and other health physics personnel monitor radiation in the Payload Hazardous Servicing Facility after three radioisotope thermoelectric generators (RTGs) were installed on the Cassini spacecraft for mechanical and electrical verification tests. 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 generate electric power. The generators enable spacecraft to operate at great distances from the Sun where solar power systems are not feasible. The Cassini mission is targeted for an Oct. 6 launch aboard a Titan IVB/Centaur expendable launch vehicle. Cassini is built and managed by JPL