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Hassium is a highly radioactive chemical element with symbol Hs and atomic number 108. The most stable known isotopes have half-lives of around 10 seconds. Natural occurrences of this superheavy element have been hypothesised, but none has ever been found. The first attempts to artificially prepare element 108 by nuclear fusion began in 1978 at the Joint Institute for Nuclear Research in the Soviet Union; though likely successful by 1984, these experiments did not prove conclusively that the element had been synthesised. For this reason, the discovery is principally credited to a team led by Peter Armbruster and Gottfried Münzenberg at the Gesellschaft für Schwerionenforschung who bombarded lead-208 with iron-58 and produced hassium-265. The name hassium was selected as a reference to the German state of Hesse, where the research was conducted. The observed chemical properties of hassium are consistent with its expected placement as the group 8 element in period 7 of the periodic table. (Full article...)