|publisher=[[National Institute of Standards and Technology]]
|accessdate=2010-09-28
}}</ref> Awanyo ukuaran ko iolah untuak satu per sapuluah juta jarak dari [[katulistiwa]] Bumi ka Kutub UtaroUtara (pado muko lauik), tapi definisinyo lah dipabaiaki sacaro periodik untuak mancaminan batambahnyo pangatuan tantang [[metrologi]]. Sajak 1983, definisinyo manjadi "panjang jalua nan dilalui dek [[kacapekan cahayo|cahayo]] dalam ruang ampo salamo interval wakatu 1/299.792.458 [[datiak]]."<ref name="Res1">{{cite web |url=http://www.bipm.org/en/CGPM/db/17/1/ |title=17th General Conference on Weights and Measures (1983), Resolution 1. |accessdate=2012-09-19}}</ref>
