atto-

In SI, the decimal submultiplier prefix meaning 10-18, or one quintillionth. Symbol, a. The growth of nuclear physics created a need for such a prefix and the physicists were the first to recognize it officially, when the General Assembly of the International Union for Pure and Applied Physics approved a proposal of its Commission on Symbols, Units and Nomenclature in 1960. Use of the atto- with SI units was officially authorized by resolution 8 of the 12th CGPM in 1964.

The prefix comes from the Danish word for eighteen.

authority

Comptes Rendus des Séances de la Conférence Generale des Poids et Mesures, 94.

Sorry. No information on contributors is available for this page.

home | units index | search |  contact drawing of envelope |  contributors | 
help | privacy | terms of use