symbols, acronyms & abbreviations

as

1

attosecond: atto- (an SI prefix meaning 1 quintillionth) + second. Used without a period. A symbol in SI, the International System of Units.

Barry N. Taylor and Ambler Thompson, editors.
The International System of Units (SI) pdf logo
NIST Special Publication 330, 2008 Edition.

“United States version of the English text of the eighth edition (2006) of the International Bureau of Weights and Measures publication Le Système International d’ Unités (SI)” This publication is the definitive guide for the United States, but the ultimate authority is the original, French version. For the symbol for the atto- see page 29, and for the second, page 23.

2

arcsecond. Alternative symbol is ″.

authority

For applications in astronomy, small angles are measured in arcseconds (i.e., seconds of plane angle), denoted by the symbol as or by the symbol ″, milliarcsecond, microarcseconds, and picoarcseconds, denoted by the symbols mas, µas, and pas, respectively, where arcsecond is an alternative name for second of plane angle.

Barry N. Taylor and Ambler Thompson, editors.
The International System of Units (SI) pdf logo
NIST Special Publication 330, 2008 Edition.
Note d, page 32.

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