Chemical elements are the building blocks of matter, and each element is defined by the unique number of protons in the nucleus of its atoms. Of the 118 known elements on the periodic table, those that do not occur naturally most often can be produced only by scientists. The first atom of element 116, livermorium, was created in 2000 after a decade of work by scientists at Lawrence Livermore National Laboratory as part of a larger scientific collaboration. One of the heaviest elements, livermorium resulted from the fusion of calcium and curium after scientists propelled calcium atoms into curium target atoms at 10 percent of the speed of light. Over three months, 10,000,000,000,000,000,000 calcium nuclei were required to produce three livermorium atoms. A livermorium atom lasts less than a tenth of a second before alpha decay converts it to flerovium and then copernicium, but a supercomputer can confirm its presence by analyzing data from radiation detectors at the experiment site. The name livermorium was approved on May 30, 2012, by the International Union of Pure and Applied Chemistry. Lawrence Livermore National Laboratory, along with other world laboratories, has created five elements on the periodic table: 114, 115, 116, 117, and 118. Livermorium was named to honor Lawrence Livermore National Laboratory and the City of Livermore, California, one of only six cities in the world with an element named after it. The City of Livermore is home to Lawrence Livermore and Sandia National Laboratories, part of the federal research system that provides the nation with strategic scientific and technology capabilities.