Mound Laboratory was the first Atomic Energy Commission site to be constructed after WWII, in order to continue Dayton’s work within the Manhattan Project and consolidate the production of polonium-210 and polonium based initiators for the first atomic bombs. Mound operated from 1948-2003 as an integrated research, development and production facility that supported the U.S. nuclear weapons, energy and space programs. Work at Mound was essential to U.S. national security during the Cold War and kept the U.S. at the leading edge of technology through the Nuclear Age and the Space Race. The Radioisotope Thermoelectric Generator (RTG), or nuclear battery, was invented by two Mound scientists in 1954. Mound RTGs power numerous NASA missions including: Apollo, Voyager, Viking, Pioneer, Cassini, Galileo, Ulysses and New Horizons. Other projects at Mound included: stable isotope separation, energetic devices, tritium containment and recovery, and fossil fuel research. At its height, Mound employed approximately 2,500 people and occupied 116 buildings across 306 of land in Miamisburg, Ohio.