Samuel Goudsmit (1902-1978) was a Dutch-American physicist.
In May 1944, Goudsmit became scientific director of the Manhattan Project's Alsos Mission, a top-secret operation responsible for gathering intelligence on Germany's atomic program. The mission investigated German scientists' progress toward nuclear weapons as the Allies liberated the European continent. While in Europe, he traveled to his childhood home in The Hague, where he found that his parents had been sent to a concentration camp and killed during the Holocaust. Goudsmit concluded that the failure of the German atomic bomb project was attributable to a number of factors, including bureaucracy, Allied bombing campaigns, the persecution of Jewish scientists, and Werner Karl Heisenberg's failed leadership.
While studying theoretical physics at the University of Leiden in 1925, Goudsmit discovered the phenomenon of electron spin with George E. Uhlenbeck.
In 1941, Goudsmit joined the Radiation Lab at the Massachusetts Institute of Technology (MIT), where he conducted radar research and headed the laboratory's document room, which contained invaluable information about German technical capacities.
After the war, Goudsmit briefly taught at Northwestern University, then was chairman of the physics department at Brookhaven National Laboratory. He also edited the American Physical Society's Physical Review for 25 years.