Two new elements have been officially added to the periodic table - twelve years after they were first discovered.
With the atomic numbers 114 and 116, they have the temporary titles of ununquadium and ununhexium. Now they've been offically recognized, their discoverers have the opportunity to give them permanent names.
They're likely to be named flerovium, after the Soviet nuclear physicist Georgy Flyorov, and moscovium, after the Russian capital.
Both elements were created at the Joint Institute for Nuclear Research in Dubna, near Moscow, in collaboration with the Lawrence Livermore national laboratory in California. In the past, the two organizations have had some disagreement about naming new, jointly-discovered elements, but it seems this time the Californians are being a little more laid-back.
The new elements aren't exactly kicking about the place; both are heavy elements created in a particle accelerator by smashing together ther nuclei of other elements. Thus, 114 was created by combining calcium with plutonium, and 116 by combining calcium and curium.
They're both highly radioactive, decaying in well under a second - making studying their properties rather difficult.
The last element to be added to the periodic table was copernicium, approved in 2009.
And, as it happens, three more may soon be joining the party. Scientists also believe they've found the elements representing positions elements 113, 115, and 118 in the periodic table.
But governing bodies the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP) say these don't yet reach the criteria neccessary for acceptance.