After weeks of blasting the element calcium with the element americium, scientists say they've confirmed the existence of the 115th element. The super-heavy new element—called "ununpentium" after its atomic number for now—was first proposed by Russian scientists in 2004 but has yet to be added to the periodic table, NPR reports. Like other elements in its part of the table, 115 is highly unstable and scientists were only able to observe it for a fraction of a second before it began to decay.
The experiment, "one of the most important in the field in recent years," also yielded new data on the structure and properties of super-heavy atomic nuclei, the team leader tells the BBC. Scientists are continuing the search for ever-heavier elements in the hope of finding an "island of stability" where super-heavy elements with as-yet-unimagined practical uses may exist, LiveScience explains. (More periodic table stories.)