Doyle Northrup; Detected First Soviet A-Bomb Blast

Doyle Northrup, 85, a physicist who detected the Soviet Union’s first atomic bomb explosion. Northrup, who held graduate degrees from the Massachusetts Institute of Technology, joined the Naval Ordnance Laboratory in 1940 and was assigned to demagnetize ships at Pearl Harbor to foil magnetic sea mines. In 1948, he transferred to the Air Force and worked as technical director of its Technical Applications Center and its Special Weapons Squadron. He was assigned to a top-secret project to test radioactivity in air samples from planes and to monitor seismographs to watch for Soviet weapons testing. In 1949, the system uncovered the first Soviet test explosion. In the 1950s, Northrup served as the scientific adviser to the American delegation in Geneva at negotiations to ban nuclear testing and to control weapons. In Melbourne, Fla., on Dec. 15.