astronomical unit

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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

A Dictionary of Earth Sciences | 1999 | | Â© A Dictionary of Earth Sciences 1999, originally published by Oxford University Press 1999. (Hide copyright information) Copyright

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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AILSA ALLABY and MICHAEL ALLABY. "astronomical unit." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. 15 Nov. 2009 <http://www.encyclopedia.com>.

AILSA ALLABY and MICHAEL ALLABY. "astronomical unit." A Dictionary of Earth Sciences. 1999. Encyclopedia.com. (November 15, 2009). http://www.encyclopedia.com/doc/1O13-astronomicalunit.html

AILSA ALLABY and MICHAEL ALLABY. "astronomical unit." A Dictionary of Earth Sciences. 1999. Retrieved November 15, 2009 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O13-astronomicalunit.html

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astronomical unit

World Encyclopedia | 2005 | Â© World Encyclopedia 2005, originally published by Oxford University Press 2005. (Hide copyright information) Copyright

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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