How many kilometers in 1 astronomical unit?
The answer is 149597870.691.
We assume you are converting between kilometre and astronomical unit.
You can view more details on each measurement unit: kilometers or
astronomical unit
The SI base unit for length is the metre.
1 metre is equal to 0.001 kilometers, or 6.6845871226706E-12 astronomical unit.
Note that rounding errors may occur, so always check the results.
Use this page to learn how to convert between kilometres and astronomical units.
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A kilometre (American spelling: kilometer, symbol: km) is a unit of length equal to 1000 metres (from the Greek words khilia = thousand and metro = count/measure). It is approximately equal to 0.621 miles, 1094 yards or 3281 feet.

››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".

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