Scientists have just made a tremendous discovery: Nihonium (Nh), moscovium (mc), tennessine (Ts), and oganesson (Og) have just been discovered and have been added to the periodic table. The International Union of Pure and Applied Chemistry (IUPAC) has approved the names and symbols for the four elements after their discovery was verified last year.

Nh, Mc, Ts, and Og have been officially designated spots 113, 115, 117, and 118 on the periodic table, completing the seventh row. They are some of the heaviest metals on the table. The elements are man-made and can only exist for fractions of a second in a lab before turning into other elements.

It’s the first time we’ve added new elements to the table since 2011, when we added livermorium (116) an dflerovium (114).

The statement from Oak Ridge National Laboratory reads: “The provisional names for 115, 117 and 118 — originally proposed by the discovering team from the Joint Institute for Nuclear Research, Dubna, Russia; the Department of Energy’s Oak Ridge National Laboratory, Oak Ridge, Tennessee, and Lawrence Livermore National Laboratory, Livermore, California; and Vanderbilt University, Nashville, Tennessee — will now undergo a statutory period for public review before the names and symbols can be finally approved by the IUPAC Council.

“Tennessine (Ts) is proposed for element 117, recognizing the contribution of Tennessee research centers ORNL, Vanderbilt, and the University of Tennessee to superheavy element research, including the production and chemical separation of unique actinide target materials at ORNL’s High Flux Isotope Reactor and Radiochemical Engineering Development Center. Actinide materials from ORNL have contributed to the discovery and/or confirmation of nine superheavy elements.”