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Related to astronomical unit: parsec
n. Abbr. AU
A unit of length used in measuring astronomical distances within the solar system or other planetary system equal to the mean distance from Earth to the sun, approximately 150 million kilometers (93 million miles).
(Units) a unit of distance used in astronomy equal to the mean distance between the earth and the sun. 1 astronomical unit is equivalent to 1.495 × 1011 metres or about 9.3 × 107 miles
a unit of length, equal to the mean distance of the earth from the sun: approximately 93 million miles (150 million km). Abbr.: AU
A unit of length equal to the average distance from Earth to the sun, approximately 93 million miles (150 million kilometers). It is used to measure distances within the solar system.
1. (au) The mean Sun to Earth distance, equal to 92,955,807 mi (149,597,870 km). Agreed internationally in 1964, but its value has altered.
2. (au) A unit of measure based on the distance between the Earth and the Sun. Approximately equal to 1.5 x 108 km.