| astronomical unit | has symbol AU |  |
| has value in SI unit 1 au = 1.49598 × 1011 m, approximately | |
| has definition Mean distance between the Earth and the Sun: 1.495985 × 1011 m. | |
| has definition The AU is the preferred unit for distances within the solar system. Mercury, the innermost planet, lies on average 0.39 AU from the Sun; Pluto, normally the farthest planet, lies on average 39.5 AU from the Sun. | |
| has definition The mean distance between the Earth and the Sun. The astronomical unit is defined as the length of the radius of the unperturbed circular orbit of a body of negligible mass moving around the Sun with a sidereal angular velocity of 0.017202098950 radian per day of 86400 ephemeris seconds. AU = 1.496 × 1013 cm ≈ 500 lt-sec. | |
| has definition The mean distance from the earth to the sun, equal to 92.81 million miles or 499.012 light-seconds. | |
| has definition The radius of a circular orbit in which a body of negligible mass, and free of perturbations, would revolve around the Sun in 2π / k days, where k is the Gaussian gravitational constant. This is slightly less than the semi-major axis of the Earth's orbit. | |
| is an instance of length unit | |
| is an instance of non SI unit | |
| length unit | is a unit of length | |
| unit | has historical origin | |
| represents | |
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