Hantaro Nagaoka (1865-1950)

Hantaro Nagaoka became the foremost Japanese professor of modern physics during the early 20th-century and was best known for his Saturnian model of the atom first proposed in 1903. Nagaoka pursued his theoretical model as a tool to account for line and band spectra, the interactions of atoms, radioactivity, and other phenomena. However, Nagaoka abandoned the model a few years later when the research of J. J. Thomson determined a fatal flaw. As a result, Nagaoka turned to spectroscopy in order to understand the arrangement of electrons in the atom. Nagaoka played a crucial role in the development of a sustained and credible research tradition in Japan during the early 20th-century. Less than 100 years after the Meiji Restoration in 1868, original research in theoretical physics resulted in Hideki Yukawa winning the Nobel Prize for Physics in 1949, an event firmly placing Japan in the advanced ranks of physics research. Nagaoka Hantaro was awarded the Order of Culture in 1937.