Spat (unit)
From HandWiki
The spat (symbol sp[1]), from the Latin spatium ("space"), is a unit of solid angle.[2][3] 1 spat is equal to 4π steradians[1][3] or approximately 41253 square degrees of solid angle (sequence A125560 in the OEIS).[2] As such, it is the solid angle subtended by a sphere at its center.[2] The spat (symbol S[4]) is also an obsolete unit of distance used in astronomy.[4][2] It is equal to 1,000,000,000 kilometres (620,000,000 mi; 6.7 astronomical unit|au).[4][2]
See also
- Turn (geometry) — the 2D counterpart of the spat, equivalent to 2π radians
References
- ↑ 1.0 1.1 The Ultimate Online Reference for Engineers. Sunnyvale, California, USA: eFunda Inc.. http://www.efunda.com/units/show_units.cfm?search_string=spat. Retrieved 2015-10-19.
- ↑ 2.0 2.1 2.2 2.3 2.4 Rowlett, Russ (2004). "A Dictionary of Units of Measurement". Chapel Hill: University of North Carolina. http://www.unc.edu/~rowlett/units/dictS.html. Retrieved 2015-10-16.
- ↑ 3.0 3.1 Glossary » Units » Solid Angle » Spat. Sunnyvale, California, USA: eFunda Inc.. http://www.efunda.com/glossary/units/units--solid_angle--spat.cfm.
- ↑ 4.0 4.1 4.2 Nouvelle encyclopédie du monde. 16. Montréal, Toronto, Paris: Éditions Leland Ltée, Librairie Aristide Quillet. 1962. p. 5426.