Otto Hahn

Otto Hahn (8 March 1879 – 28 July 1968) was a German <a href="/facts/Chemist/N09K7Bdm">chemist</a> who was a pioneer in the field of <a href="/facts/Radiochemistry/vdL6AaCH">radiochemistry</a>. He is referred to as the father of <a href="/facts/Nuclear_chemistry/aJulAlTD">nuclear chemistry</a> and discoverer of <a href="/facts/Nuclear_fission/LfkIylvm">nuclear fission</a>, the science behind <a href="/facts/Nuclear_reactor/8xqjIbge">nuclear reactors</a> and <a href="/facts/Nuclear_weapon/QVdBcMdm">nuclear weapons</a>. Hahn and <a href="/facts/Lise_Meitner/BH51ypJ2">Lise Meitner</a> discovered isotopes of the radioactive elements <a href="/facts/Isotopes_of_radium/T0SlGtRH">radium</a>, <a href="/facts/Isotopes_of_thorium/lRb3opzg">thorium</a>, <a href="/facts/Isotopes_of_protactinium/AVGw4A8U">protactinium</a> and <a href="/facts/Isotopes_of_uranium/zWIQ6MVL">uranium</a>. He also discovered the phenomena of <a href="/facts/Atomic_recoil/9DoQJ7At">atomic recoil</a> and <a href="/facts/Nuclear_isomerism/L8DHcqnk">nuclear isomerism</a>, and pioneered <a href="/facts/Rubidium%E2%80%93strontium_dating/F1NA2T58">rubidium–strontium dating</a>. In 1938, Hahn, Meitner and <a href="/facts/Fritz_Strassmann/UJLrswVu">Fritz Strassmann</a> <a href="/facts/Discovery_of_nuclear_fission/5y87GGpg">discovered nuclear fission</a>, for which Hahn alone was awarded the 1944 <a href="/facts/Nobel_Prize_in_Chemistry/8Nb8Ajjy">Nobel Prize in Chemistry</a>.
A graduate of the <a href="/facts/University_of_Marburg/L2BXUghC">University of Marburg</a>, which awarded him a doctorate in 1901, Hahn studied under Sir <a href="/facts/William_Ramsay/fGzWlHlP">William Ramsay</a> at <a href="/facts/University_College_London/7dmHhCf5">University College London</a> and at <a href="/facts/McGill_University/amouytVp">McGill University</a> in Montreal under <a href="/facts/Ernest_Rutherford/hjjMEskl">Ernest Rutherford</a>, where he discovered several new radioactive isotopes. He returned to Germany in 1906; <a href="/facts/Emil_Fischer/5wxbfBtu">Emil Fischer</a> let him use a former woodworking shop in the basement of the Chemical Institute at the <a href="/facts/University_of_Berlin/QE2lhhkd">University of Berlin</a> as a laboratory. Hahn completed his <a href="/facts/Habilitation/VSEhfx78">habilitation</a> in early 1907 and became a <a href="/facts/Privatdozent/Cd6m1pFt">Privatdozent</a>. In 1912, he became head of the Radioactivity Department of the newly founded <a href="/facts/Kaiser_Wilhelm_Institute_for_Chemistry/FeQcYSho">Kaiser Wilhelm Institute for Chemistry</a> (KWIC). Working with Austrian physicist Lise Meitner in the building that now bears their names, they made a series of groundbreaking discoveries, culminating with her isolation of the longest-lived isotope of protactinium in 1918.
During <a href="/facts/World_War_I/vITTUanQ">World War I</a> he served with a <a href="/facts/Landwehr/j0xAvRsl">Landwehr</a> regiment on the <a href="/facts/Western_Front_(World_War_I)/RrhMPVQP">Western Front</a>, and with the <a href="/facts/Chemical_warfare/zT4t2DGk">chemical warfare</a> unit headed by <a href="/facts/Fritz_Haber/cj5QTJKT">Fritz Haber</a> on the Western, <a href="/facts/Eastern_Front_(World_War_I)/jEzn7l88">Eastern</a> and <a href="/facts/Italian_front_(World_War_I)/EduvVolR">Italian</a> fronts, earning the <a href="/facts/Iron_Cross/Wh9hYXbC">Iron Cross</a> (2nd Class) for his part in the <a href="/facts/First_Battle_of_Ypres/CzP0w2bx">First Battle of Ypres</a>. After the war he became the head of the KWIC, while remaining in charge of his own department. Between 1934 and 1938, he worked with Strassmann and Meitner on the study of isotopes created by neutron bombardment of uranium and thorium, which led to the discovery of nuclear fission. He was an opponent of <a href="/facts/Nazism/JjsMI4lE">Nazism</a> and the <a href="/facts/The_Holocaust/vGQsAb2y">persecution of Jews</a> by the <a href="/facts/Nazi_Party/qQCramHd">Nazi Party</a> that caused the removal of many of his colleagues, including Meitner, who was forced to flee Germany in 1938. During <a href="/facts/World_War_II/2efV5L1U">World War II</a>, he worked on the <a href="/facts/German_nuclear_weapons_program/Eot0thNx">German nuclear weapons program</a>, cataloguing the <a href="/facts/Fission_product/xJd9MXXH">fission products</a> of uranium. At the end of the war he was arrested by the Allied forces and detained in <a href="/facts/Farm_Hall/5Dlgdsz8">Farm Hall</a> with nine other German scientists, from July 1945 to January 1946.
Hahn served as the last president of the <a href="/facts/Kaiser_Wilhelm_Society/FeQcYSho">Kaiser Wilhelm Society for the Advancement of Science</a> in 1946 and as the founding president of its successor, the <a href="/facts/Max_Planck_Society/lVNb39aD">Max Planck Society</a> from 1948 to 1960. In 1959 in Berlin he co-founded the <a href="/facts/Federation_of_German_Scientists/ttMzrtUk">Federation of German Scientists</a>, a non-governmental organisation committed to the ideal of responsible science. As he worked to rebuild German science, he became one of the most influential and respected citizens of post-war <a href="/facts/West_Germany/oCydk787">West Germany</a>.

Otto Hahn open-in-new

Otto Hahn