Posters in chemistry labs are in need of an update. The periodic table now has four new elements, completing its seventh row. The International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP) have recognised the discoveries of elements 113, 115, 117 and 118. They were created by teams of researchers in Japan, Russia and the US, who smashed lighter nuclei into each other. The resulting superheavy elements, like others of their kind, exist for only a fraction of a second before decaying into lighter atoms.