Otto Hahn (8 March 1879 – 28 July 1968) was a German chemist who was a pioneer in the fields of radioactivity and radiochemistry. He is referred to as the father of nuclear chemistry and godfather of nuclear fission. Hahn and Lise Meitner discovered radioactive isotopes of radium, thorium, protactinium and uranium. He also discovered the phenomena of radioactive recoil and nuclear isomerism, and pioneered rubidium–strontium dating.

Otto Hahn was born in Frankfurt am Main on 8 March 1879, the youngest son of Heinrich Hahn (1845–1922), a prosperous glazier (and founder of the Glasbau Hahn company), and Charlotte Hahn née Giese (1845–1905). The family lived above his father's workshop.

In 1897, after taking his Abitur, Hahn began to study chemistry at the University of Marburg. His subsidiary subjects were mathematics, physics, mineralogy and philosophy.

In 1901, Hahn received his doctorate in Marburg for a dissertation entitled "On Bromine Derivates of Isoeugenol", a topic in classical organic chemistry. He completed his one-year military service (instead of the usual two because he had a doctorate) in the 81st Infantry Regiment, but unlike his brothers, did not apply for a commission. He then returned to the University of Marburg, where he worked for two years as assistant to his doctoral supervisor, Geheimrat Professor Theodor Zincke.

In 1938, Hahn, Lise Meitner and Fritz Strassmann discovered nuclear fission, for which Hahn received the 1944 Nobel Prize for Chemistry. Nuclear fission was the basis for nuclear reactors and nuclear weapons.

According to wikipedia