• We're missing an atom
The periodic table remains one of the few markers of stability in the ever-changing world of scientific theory. So in 1999, it was with much fanfare that Kenneth Gregorich, a nuclear chemist at the Lawrence Berkeley National Laboratory, and his colleagues announced that they had discovered two new elements not in the table. By crashing krypton particles into a chunk of lead, they had created element 118 and the element into which it rapidly decayed, element 116. (The numbers 118 and 116 refer to how many protons are in the nucleus of the atoms.) It was with less of a flourish that they retracted their claim last July. After two years of futile attempts to reproduce the elusive atoms, Gregorich and his team reanalyzed their data and discovered that there was no "there" there. The decay chains they thought they had seen, from element 118 to 116 to 114 and so on, until the atom reached the more stable element 106, were nowhere to be found. As far as the periodic table goes, element 118 wasn't around long enough to get a real name; scientists referred to it only by its assigned nomenclature: ununoctium.
Although 118 is off the chart for now, other chemists hope it will return. John Wild, a nuclear chemist at Lawrence Livermore National Laboratory, says: "Element 118 does exist; it just hasn't been discovered yet. It'll be made sometime in the future, I'm sure." He should know. In conjunction with a team in Russia, using a different method than Gregorich employed, he created—and confirmed the existence of—element 116.
— Lauren Gravitz