Leona Woods Leona Woods Leona Harriet Woods (August 9, 1919 – November 10, 1986), later known as Leona Woods Marshall and Leona Woods Marshall Libby, was an American physicist who helped build the first nuclear reactor and the first atomic bomb. At age 23, she was the youngest and only female member of the team which built and experimented with the world's first nuclear reactor (then called a "pile"), Chicago Pile-1, in a project led by her mentor Enrico Fermi. In particular, Woods was instrumental in the construction and then utilization of geiger counters for analysis during experimentation. She was the only
S1W reactor S1W reactor The S1W reactor was the first prototype naval reactor used by the United States Navy to prove that the technology could be used for electricity generation and propulsion on submarines. The S1W designation stands for The land-based nuclear reactor was built at the National Reactor Testing Station, later called Idaho National Engineering Laboratory near Arco, Idaho. The plant was the prototype for the USS "Nautilus" (SSN-571), the world's first nuclear-powered submarine. The specific location within the vast Idaho National Laboratory where the S1W prototype was located was the Naval Reactors Facility. Under the leadership of Admiral Hyman G.