Roentgenium is a synthetic element that was first produced in 1994 by a team of German physicists at the Institute for Heavy Ion Research in Darmstadt. It is highly radioactive and very unstable, with a half-life of only a few seconds. Because of its extreme rarity and short half-life, very little is known about its chemical and physical properties. However, scientists believe that it is a metal and that it belongs to the group of elements known as the transition metals. Roentgenium is named after Wilhelm Conrad Roentgen, the German physicist who discovered X-rays, in recognition of his pioneering work in the field of radiation.