Hassium is a chemical element with symbol Hs and atomic number 108, named in honor of the German state of Hesse. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 269Hs, has a half-life of approximately 9.7 seconds, although an unconfirmed metastable state, 277mHs, may have a longer half-life of about 11 minutes. More than 100 atoms of hassium have been synthesized to date.Symbol: Hs
Atomic number: 108
Discovered: 1984
CAS ID: 54037-57-9
Van der Waals radius: 200 pm
Atomic mass: 277 u