Newsletter 2 2008

German Stars - Innovations made in Germany

Nuclear fission - Energy and its side effects

When in 1938 chemist Otto Hahn, his assistant Fritz Strassmann and physicist Lise Meitner began bombarding radioactive uranium with neutrons, they hoped that the end product would be heavier than uranium. The outcome of the experiment was puzzling. Though the three researchers had expected to produce a new element, they now found that barium, a much lighter element, was one of the by-products of the reaction. The scientists came to a startling conclusion: rather than creating a neighbour of uranium, what had taken place was fission of the nucleus, with barium and krypton being produced as a result of the neutron bombardment. The energy released was 200 mega electron volts, which in turn liberated neutrons which triggered a chain reaction. The number of fissions was compounded and the energy obtained exceeded that released by coal millions of times over.

Significance: with their discovery of nuclear fission, Hahn, Meitner and Strassmann paved the way for two important developments: nuclear power, and the atomic bomb.

Invented by: Otto Hahn
In: 1938
Special Information: Hahn was well aware of the potential dangers of his invention. Together with 17 other German nuclear physicists, he signed the Göttingen Declaration in 1957 to oppose plans of the German Army to acquire nuclear weapons.

Source:
fischerAppelt Kommunikation GmbH
Friedrichstr. 149 | D-10117 Berlin | Germany
http://www.fischerappelt.de/