Hantaro Nagaoka, the Japanese physicist whose atomic model inspired Rutherford’s

Hantaro Nagaoka (1865–1950) was a prominent Japanese physicist who, after studying in Germany and Austria from 1893 to 1896, proposed a revolutionary atomic model in 1904 known as the “Saturnian model.” Rejecting J.J. Thomson’s “plum‑pudding” model, Nagaoka argued that one charge could not contain another of the same sign in the way Thomson suggested. His model envisioned an atom with a large central sphere of positive charge (a precursor to the nucleus) surrounded by electrons orbiting in rings, much like Saturn’s rings. Although the model was later discarded because of electromagnetic stability issues, the concept of a central positive mass was pivotal and served as an important inspiration for the nuclear atomic model that Ernest Rutherford would develop a few years later in 1911.