Harold Urey discovered deuterium in 1931. A deuterium is an isotope of hydrogen that contains one proton and one neutron.
< Harold Urey
James Chadwick discovered the neutron in February of 1932.
Max Born and James Franck are compelled to leave their posts at German universities because of their "Jewish physics."
Curie discovers artificial radioaactivity.
Enrico Fermi irradiates uranium with neutrons in 1934.
< Harold Urey < Harold Urey