The discovery of the atomic nucleus, or perhaps better stated the development of theory of the nucleus, is credited to ernest rutherford in 1911. he was a kiwi physicist who worked in the laboratory of jj. tomson, who developed the earlier plum pudding model of the atom. a few years earlier, in 1904, japanese physicist hantaro nagaoka postulated the saturnian model of the atom where he envisioned a very heavy positively charged center of the atom with electrons orbiting much like the rings of saturn. what are the similarities and differences between the nagaoka and rutherford models of the atom? if he developed his theory about 7 years earlier than rutherford, why is nagaoka not credited with the discovery of the nucleus? hint: what's a nucleus anyways