Historical overview of the US use of space nuclear power

Since 1961, the United States has successfully flown 35 space nuclear power sources on 20 space systems. These space systems have included the Apollo, Pioneer, Viking and Voyager spacecraft launched by the National Aeronautics and Space Administration and navigation and communications satellites launched by the Department of Defense. These power sources performed as planned and i8n many cases exceeded their power requirements and/or lifetimes. All of the power sources met their safety requirements. This paper surveys past uses of space nuclear power in the US and thus serves as a historical framework for other papers in this Conference dealing with future US applications of space nuclear power.