science · 08 December 1994 · 30 years ago
In 1994, approximately one month after announcing the creation of element 110, a team of German scientists led by Peter Armbruster at the Gesellschaft für schwerionenforschung (GSI) facility at Darmstadt, Germany, claimed to have created element 111. Its atom has 111 protons and 161 neutrons in its nucleus, giving it a mass number of 272. As a new element it was named unununium, symbol Uuu, according to an internationally adopted system for naming new elements. Only three atoms of the element were made by accelerating nickel atoms to high speed and bombarding them into bismuth. When an atom of each fused to make the new nucleus, it lasted for about four-thousandths of a second before decaying into smaller nuclei.
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