Various constants and reference quantities
Fundamental physical constants

The value 1 AU = 149,600 × 10⁶ m is adopted by convention in the International Astronomical Union's system of astronomical constants.

The astronomical unit is roughly equal to the radius of the undisturbed circular orbit of a body of negligible mass moving around the Sun with a sidereal angular velocity of 0.017,202,098,950 radians per day of 86,400 ephemeris seconds (cf. the article Constants in astronomy from this treatise). The value that corresponded...