It's defined as the average distance between the earth and sun, roughly 93 million miles.
The distance between the Earth and the Sun. Aproximatly 149 598 000 kilometers
4640000/498659569 astronomical units and 13910000/1495978707 astronomical units
One Astronomical Unit (abbreviated AU) is the distance from the Sun to the Earth, which is 93 million miles. So the Earth's orbital radius 1 AU.
AU
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