They’re the heaviest members yet of the periodic table, with whopping atomic weights of 289 and 292 atomic mass units respectively. The previous heavyweight winners were copernicium (285) and roentgenium (272).
The two new elements are radioactive and only exist for less than a second before decaying into lighter atoms. Element 116 will quickly decay into 114, and 114 transforms into the slightly lighter copernicium as it sheds its alpha particles.
Evidence for the two elements has been mounting for years. In 1999, for example, Russian physicists bombarded plutonium-244 with calcium-48 to produce a single atom of rapidly decaying 114.Read more
How to put a new element on the Periodic Table