Hans Geiger was born in Neustadt, Germany, in 1882. He studied physics in Munich and Erlangen before moving to Manchester to study under Ernest Rutherford. Over the next couple of years Geiger studied the mathematical relationship between the amount of alpha scattering and atomic weight.
When Geiger returned to Germany in 1912 and was appointed as head of the Physikalische Technische Reichsanstalt in Berlin. He continued to work in the field of atomic research and in 1928 he produced an instrument that could detect and count alpha particles called the Geiger Counter.
In later years Geiger concentrated on researching cosmic radiation. Hans Geiger died in 1945.