Hassium is a synthetic element that was first synthesized in 1984 by a German research team led by Peter Armbruster and Gottfried Munzenberg. It was named after the German state of Hesse, where the research was conducted. Hassium is a highly unstable element, and its longest-lived isotope has a half-life of approximately 10 seconds. Its chemical properties are not well understood due to its short half-life and the minute amounts in which it has been produced.