What is Oganesson?

Oganesson (Og) is a chemical element with a history.

The possibility of a seventh noble gas (after helium, neon, argon, krypton, xenon and radon) was considered soon after the noble gas group was discovered. In April 1895 the Danish chemist Julius Thomsen predicted the existence of the element now known as oganesson. In 1922 Niels Bohr noted that the seventh noble gas should have atomic number 118 and predicted its electronic structure. These predictions were correct, but the search for element 118 followed a false trail in the late 1990s.

In 1998, it was suggested that one could synthesise element 118 by fusing lead with krypton. In 1999, researchers at Lawrence Berkeley National Laboratory followed this up and announced the discovery of element 118. But researchers at other laboratories were unable to duplicate the results and the Berkeley lab could not duplicate them either! In 2002 it was admitted that the "discovery" had, in fact, been based on data fabricated by the report's principal author.

The true discovery of element 118 was made in 2002 at the Joint Institute for Nuclear Research in Dubna, Russia. This was achieved by a joint team of Russian and American scientists, headed by nuclear physicist Yuri Oganessian. On 28 November 2016 his name was given to the new element.

So, 121 years after Thomsen's 1895 prediction, "oganesson" officially joined the periodic table. It is one of only two elements named after a person who was alive at the time of naming.