What is one astronomical unit (AU) in meters?
One astronomical unit is 1 au = 1.49597870700e11 m exactly (IAU 2012 definition), about 149.6 million kilometres.
Open the interactive PhysRef tool →Key facts
| Value | 1.49597870700e11 m |
|---|---|
| Symbol | au |
| In km | ≈ 149,597,871 km |
| Exactness | Exact by IAU 2012 definition |
| Source | IAU 2012 (Resolution B2) |
Frequently asked questions
How many meters is 1 AU?
1 au = 1.49597870700e11 m, defined exactly by the IAU in 2012, roughly the Earth-Sun distance.
How many kilometers is an astronomical unit?
About 149.6 million km (149,597,871 km).
What is the AU used for?
It is a convenient unit for distances within the Solar System, such as planetary orbital radii.
Related pages
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