The periodic table of the elements has grown ever since the first version was published by Dmitri Mendeleev in 1869. And now scientists in Sweden suggest it’s time to add yet another element to the table.

New research confirms the existence of a super-heavy, radioactive element with atomic number 115. Its temporary name is ununpentium (Uup), as the element has yet to be named formally. The research was conducted at the GSI accelerator facility near Darmstadt, Germany, where scientists are known for having discovered six other elements since the early 1980s.

“This was a very successful experiment and is one of the most important in the field in recent years,” lead researcher Dr. Dirk Rudolph, physics professor at the University of Lund in Sweden, said in a written statement.

Evidence for element 115 was first discovered by Russian scientists in 2004. But additional research now has confirmed that the element’s atomic number — the number of protons in the nucleus of one atom of the substance — is 115, BBC News reports.