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astronomical unit

astronomical unit (AU), mean distance between the earth and sun; one AU is c.92,960,000 mi (149,604,970 km). The astronomical unit is the principal unit of measurement within the solar system, e.g., Mercury is just over 1/3 AU and Pluto is about 39 AU from the sun.

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astronomical unit

astronomical unit (AU) Mean distance between the Earth and the Sun, used as a fundamental unit of distance, particularly for distances in the Solar System. It is equal to 149.598 million km (92.956 million mi).

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astronomical unit

astronomical unit (AU) The average distance between the Earth and Sun; a unit of measurement equal to 149 597 870 km.

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"astronomical unit." A Dictionary of Earth Sciences. . Encyclopedia.com. 23 Apr. 2018 <http://www.encyclopedia.com>.

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