Scientists confirm element 117

This superheavy was produced for the second time — and by a different team of researchers than four years ago — proving that ununseptium is real

The second time’s the charm. For the second time in four years, scientists report creating a new element with 117 protons in its nucleus. That new report confirms element 117’s existence.

Both times, scientists reported making only a small amount. Several atoms. And they lasted for less than a second before breaking apart. But that was enough.

Scientists first claimed to make the element in 2010.The science community wanted to be sure that discovery was real, however, before celebrating its birthday. There was always the chance someone might have made a mistake interpreting the data.

The new announcement means chemists will likely soon be adding number 117 to their periodic table of the elements. The new entrant’s name? Unofficially, scientists are calling it ununseptium. Not terribly clever, it’s based on the Latin for one-one-seven. But that name is only temporary. Those who first created 117 should get a chance to rename it before long.

Uranium is the heaviest naturally occurring element on Earth (at least in substantial quantities). It’s number 92 on the periodic table. But for decades, scientists have been bombarding big elements with smaller ones. Their goal has been to briefly fuse them. That creates a superheavy. Depending on who you talk to, a superheavy is an either an element bigger than uranium or one more massive than rutherfordium (number 104).

For now, number 117 is the most massive element confirmed to exist. In 2006, researchers reported creating one slightly bigger: ununoctium, or number 118. But such superheavy elements must be created more than once, by different researchers. Until that happens, the scientific community will not formally accept that their existence is real. Ununoctium is still awaiting such a confirmation through a second set of tests.

The creation of element 117 began with another element, berkelium (number 97). For more than a year, researchers at the Department of Energy’s Oak Ridge National Laboratory, in Oak Ridge, Tenn., worked to make some 13 milligrams of almost pure berkelium. They shipped the radioactive element to Mainz University in Germany. There, researchers bombarded it with a high-energy beam of calcium ions. A small number of the smash-ups resulted in fusion reactions. A few atoms of element 117 emerged from those reactions.

The researchers didn’t actually “see” the new element. They deduced its creation by studying its radioactive decay. That’s when an atom sheds subatomic particles (here alpha particles). All radioactive elements, including number 117, decay. It means they break into smaller atoms or spit out subatomic particles. In the new tests, scientists quantified each successive decay of the original element and its breakdown products — known as daughters. That let them confirm that the short-lived parent must have been element 117.

In all, 72 scientists and engineers from 16 different research centers took part in the new project. They reported their achievement May 1 in Physics Review Letters.

Although element 117 was short-lived, scientists suspect some superheavies might be relatively long-lived. Such elements would exist in a so-called island of stability. Looking to find that island is one reason that scientists pursue this costly and time-consuming quest for ever-heavier elements.