The image aims to suggest a self-propagating nuclear chain reaction, such as occurs in nuclear reactors and atomic bombs.

Fact Box

Uses

Fermium has no uses outside research.

History

Fermium was discovered in 1953 in the debris of the first thermonuclear explosion which took place on a Pacific atoll on 1 November 1952. In this a uranium-238 bomb was used to provide the heat necessary to trigger a thermonuclear explosion. The uranium-238 had been exposed to such a flux of neutrons that some of its atoms had captured several of them, thereby forming elements of atomic numbers 93 to 100, and among the last of these was an isotope of element 100, fermium-255. News of its discovery was kept secret until 1955.