August 1977 The Voyager 2 spacecraft is launched. The spacecraft's electricity is generated by the decay of plutonium pellets

April 1978 The United States cancels development of the neutron bomb, which would theoretically destroy life but leave buildings intact

March 1979 Three Mile Island Nuclear Powerplant near Harrisburg, Pennsylvania suffers a partial core meltdown. Minimal radioactive material is released

June 1979 The United States and Soviet Union sign the Strategic Arms Limitation Treaty (SALT) II, which limits each side's arsenals and restricts weapons development and modernisation

1982 The Shipping Port nuclear powerplant, built in 1957, is retired. This is the first complete decontamination and decommissioning of a reactor in the United States

August 1985 The Soviet Union announces a nuclear testing moratorium

*Source: US dept. of energy office of environmental management & nuclearfiles.org