Nuclear power and nuclear medicine are two examples of peaceful uses of atomic energy. Nuclear energy to produce electricity commercially began in the U.S. in 1957. Today, over 100 nuclear power plants produce about 21 percent of all the electricity generated in the United States. A 1979 accident at Three Mile Island in Pennsylvania made many Americans uncertain about the safety of nuclear power. Utilities must follow a lengthy series of licensing procedures before a nuclear power plant can be built and operated in the United States.
Nuclear medicine is a medical specialty which is used to image the body and treat disease.
Nuclear medicine imaging is unique in that it documents organ function and structure, in contrast to diagnostic radiology which is based upon anatomy. The Space Age has run almost in tandem with the Atomic Age. In 1957, the Soviet Union launched the first satellite, Sputnik I, and the United States followed with Explorer I in 1958. The first manned space flights were made in the spring of 1961, first by Soviet cosmonaut Yuri Gagarin and then by American astronaut, Alan B. Shepard, Jr. From the first tentative steps of the 1969 moon landing to today's reusable space shuttle , the space program has produced a range of secondary uses of aerospace technology.