Four new names will soon be added to the periodic table of elements, the all-important single document containing nearly all of what we know about chemistry. Last December, the International Union of Pure and Applied Chemistry recognized elements 113, 115, 117 and 118 (their respective atomic numbers) as the newest additions to the periodic table. After months of suspense, the organization has finally proposed names for the four new elements, chosen by the scientists who discovered them.

Nihonium (Nh). Moscovium (Mc). Tennessine (Ts). Oganesson (Og). Meet the potential new names (and symbols) for the elements formerly known as 113, 115, 117 and 118, according to a proposal presented this week by the International Union of Pure and Applied Chemistry (Iupac). Three of the names honor the places the elements were discovered–Moscow, Japan and Tennessee–while the fourth is named for the 83-year-old Russian physicist Yuri Oganessian, who becomes only the second living scientist to have an element named for him.

The history of the periodic table, which hangs on the wall of nearly every laboratory and science classroom in the world, dates back at least two centuries. When Russian chemistry professor Dimitri Ivanovich Mendeleev completed the first version of the periodic table in 1869, he was building on the work of past chemists, who had made various attempts to organize the known chemical elements in a meaningful way. Mendeleev’s crucial innovation was to notice a recurring pattern, or “periodic law,” in the properties of the elements, that allowed him to create the now-famous arrangement of rows and columns. In addition, Mendeleev left spaces for elements yet to be discovered, and even predicted their atomic weights. The periodic table has been much debated, changed and improved since that time, but its essential nature has remained the same–despite the dramatic advances made in the scientific world over that same time period.

All four of the elements being named are what are known as superheavy (or heavy metal) elements, which do not naturally occur in nature. Instead, scientists create these radioactive elements in trace amounts in a laboratory by smashing lighter atomic nuclei together. The resulting superheavy elements last only fractions of a second before breaking apart into smaller, more stable fragments.

After Iupac officially verified the four new elements late in December 2015, the organization gave naming rights to the scientists and laboratories that discovered them. According to Iupac’s naming conventions, new elements can be named after one of their chemical or physical traits, a mineral or similar substance, a mythological character or concept, a place (e.g. a city, country, geographical region) or a scientist.

Kosuke Morita, who led the team at Riken institute that discovered the superheavy synthetic element, smiles as he points to a board displaying the new element 113.  (Credit: JIJI PRESS/AFP/Getty Images)
Kosuke Morita, who led the team at Riken institute that discovered the superheavy synthetic element, smiles as he points to a board displaying the new element 113. (Credit: JIJI PRESS/AFP/Getty Images)

A Russian-American team working at three different research institutions–the Joint Institute for Nuclear Research in Dubna, Russia; the Oak Ridge National Laboratory at Vanderbilt University in Tennessee; and the Lawrence Livermore National Laboratory in California–discovered elements 115, 117 and 118. Muscovium and tennessine, the new names for 115 and 117, respectively, honor the places where they were discovered: Moscow, which is near Dubna, and Tennessee. Tennessee is the second state to be recognized in the name of an element, after California (californium).

Oganesson, the proposed name for element 118, is a somewhat more unusual choice. The Russian-American team chose to honor Oganessian, a researcher at the Dubna-based institute who spearheaded the discovery of superheavy elements. This is only the second time that an element has been named for a living scientist. In 1993, Iupac initially rejected the proposal to name element 106 seaborgium after Glenn Seaborg, an American nuclear-chemistry pioneer. The organization even passed a resolution that elements not be named for living scientists, but ended up backing down from that stance.

Nihonium, the proposed name for element 113, is the first artificial element to be discovered in an East Asian country. “Nihon” is one of two Japanese words for Japan (the other is “Nippon”). According to an official at the RIKEN Nishina Center for Accelerator-based Science near Tokyo, which made the discovery, the name recognizes government funding of the project, as well as the support of the Japanese people.

The four proposed names will undoubtedly disappoint some members of the public, who came up with their own, more colorful suggestions. Some 150,000 people signed a petition arguing that element 115 should be named “lemmium” after Ian “Lemmy” Kilmister of the heavy metal band Motorhead, who died in late December 2015. Arguing that Iupac should change its naming criteria in order to accept its submission, the petition called Kilmister “the very essence of heavy metal.”

An additional 50,000 people wanted element 117 to become “octarine,” as a tribute to the late Terry Pratchett, author of the bestselling Discworld book series. Pratchett, who also died in 2015, was well known for his love of science. In the Discworld books, “octarine” is known as “the color of magic,” and the petition argued that the name qualified under the category of mythological concept, according to Iupac’s guidelines.

Nihonium, moscovium, tennessine and oganesson must now undergo a five-month probation period, in which people can offer their objections to the proposed names. Iupac has the final say on all names, however, and barring some large public outcry the organization is expected to make the names official in November. The four elements will complete the seventh row of the periodic table, which is currently being occupied by the relatively meaningless placeholders of ununtrium, ununpentium, ununseptium and ununoctium.