Learning Ashram

Element 117 Is Here!

It's taken years, but physicists have finally filled in a persistent gap in the periodic table. Eight years after the creation of element 118, the heaviest known atom, researchers have made a few atoms of its slightly lighter neighbor, element 117, by shooting an intense beam of calcium ions into a target of berkelium. Besides sketching in the blank space in the table, the discovery bolsters the notion of an "island of stability," a group of superheavy nuclei still tantalizingly out of reach that theorists predict may be as stable as more familiar elements.

The 92 elements naturally found on Earth have one thing in common: they have been stable enough to hang around over the 4.5 billion years of our planet's existence. Those beyond the 92nd element, uranium, have shorter half-lives and have been manufactured in nuclear reactors or by particle accelerators. As more were discovered, the trend seemed be toward shorter and shorter half-lives as mass increased. But in the 1960s, nuclear physicists discovered that certain key numbers of protons and neutrons conferred extra stability on a nucleus. If there were such “magic numbers” larger than those seen in existing elements, perhaps some superheavy elements with quantities of protons or neutrons close to those numbers would last much longer, producing a so-called island of stability. If such stable superheavies could be found and made in quantity, they could have exotic and useful chemical properties.