›› Measurement unit: astronomical unit

Full name: astronomical unit

Plural form: astronomical units

Symbol: AU

Category type: length

Scale factor: 149597870691


›› SI unit: metre

The SI base unit for length is the metre.
1 metre is equal to 6.6845871226706E-12 astronomical unit.


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›› Definition: Astronomical unit

The astronomical unit (AU or au or a.u. or sometimes ua) is a unit of length. It is approximately equal to the mean distance between the Earth and Sun. The currently accepted value of the AU is 149 597 870 691 ± 30 metres (about 150 million kilometres or 93 million miles).

The symbol "ua" is recommended by the Bureau International des Poids et Mesures, but in the United States and other anglophone countries the reverse usage is more common. The International Astronomical Union recommends "au" and international standard ISO 31-1 uses "AU".


›› Sample conversions: astronomical unit

astronomical unit to shaftment [ancient]
astronomical unit to lug [great]
astronomical unit to league [UK]
astronomical unit to vara [California]
astronomical unit to nail
astronomical unit to gigalight year
astronomical unit to mile [Irish]
astronomical unit to el [Dutch]
astronomical unit to toise
astronomical unit to palm [Britain, Roman minor]