Robert Nobles (1917-2007) was an American physicist who worked on the Manhattan Project at the University of Chicago with Enrico Fermi. He was a member of a group conducting experiments to determine the correct size and the arrangement of graphite and uranium in Chicago Pile-1, the first nuclear reactor. His group also played an active part in the actual construction of the pile.
Robert was one of three brothers who worked on the Manhattan Project – his brothers Ralph and William both worked at Los Alamos.