Rare element, atomic number 118, mildly radioactive and a proven room temperature superconductor. Onnesium is normally found as small, silvery spheres embedded within meteoric nickel-iron. Created within supernovae, onnesium is plated onto asteroidal surfaces, and can eventually be discovered in free-floating or in impact craters upon planetary surfaces.
Recent discoveries in the Gavza system (Reavers' Deep 1117) have suggested that a supernova at Reavers' Deep 1118 may have spread onnesium to several nearby systems within the Scotian Deep subsector.