Hantaro Nagaoka

Nagaoka Hantaro (Japanese长 冈 半 太郎, born August 15, 1865 in Omura ( Nagasaki ), † December 11, 1950 in Tokyo ) was a Japanese physicist.

He studied at the University of Tokyo mathematics and physics, among others, the then teaching English there physicists EA Ewing, CG Knott (especially on magnetism ). After graduating in 1887 he went to Europe, where he from 1893 to 1896 in Berlin heard among others, Max Planck, Hermann von Helmholtz and August Kundt and Ludwig Boltzmann in Vienna. Upon returning to Japan, he became a professor of theoretical physics at the University of Tokyo. His specialty was the magnetism, where he worked from 1900 with Kotaro Honda ( 1870-1954 ).

In 1904, he developed an early " planetary model " of the atom ( " Saturnian theory" ), which describes the atom as a large, positively charged sphere which is orbited by negatively charged electrons. From 1931 to 1934 he was president of the University of Osaka.

In 1910 he was Head of the founding conference (of Japanese foreign students and researchers ) of Tohoku University in Paris, which was to be modeled after the University of Göttingen. From 1916 until his retirement in 1926 Nagaoka was the director of the Physics Institute of the University of Tokyo and worked simultaneously on the private research institute Riken ( 1917-1946 ). 1939 to 1948 he was president of the Japan Academy of Sciences.

Nagaoka is considered one of the pioneers of physics in Japan, the much promoted their connection to the European and U.S. research. Among his pupils was the theoretical physicist June Ishihara ( 1881-1947 ).

After a Nagaoka crater was named on the moon.