Four newly discovered elements have been added to the periodic table, filling up the table’s seventh row and marking the first additions since 2011. To gain a spot on the periodic table, an element has to pass muster with the International Union of Pure and Applied Chemistry (IUPAC).

Elements at the outer bounds of the periodic table are what chemists call superheavy (a reference to their increasing number of protons that correspond to their number on the table). Created artificially by slamming nuclei into one another in the lab, these heavyweight champs last for just tiny fractions of a second before decaying into elements we can’t detect. So when someone claims to have identified an element with an all-time high atomic number, the powers that be have to do a little follow-up. In this case, three of the new elements (115, 117 and 118) were approved with credit to a team of Russian and U.S. scientists; a fourth they had attempted to claim (113) was credited to a team in Japan after IUPAC’s assessment.

The temporary names: ununtrium, ununpentium, ununseptium and ununoctium.

Washington Post