A Radioisotope Thermoelectric Generator (RTG) is a display model by Lockheed Martin at the STAIF Conference. This model device was employed on a number of unmanned space missions, including the Cassini and Huygens probes,

Space nuclear RTG generators are commonly employed for missions to Jupiter and the outer solar-system because they produce electricity by the decay of radioactive isotopes rather than relying on solar energy as do many other space power technologies. Relying on radioactive decay means they can operate at distances where solar power may not be available, and can do so reliably for decades or longer.