Daily Almanac for
Dec 7, 2009
Search White Pages
Search: Infoplease Info search tips
Search: Biographies Bio search tips
Encyclopedia

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.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2007, Columbia University Press. All rights reserved.

    • Cite
    • Print
    • Bookmark

More on astronomical unit from Infoplease:

See more Encyclopedia articles on: Astronomy: General


Premium Partner Content
HighBeam Research

Related content from HighBeam Research on: astronomical unit

Additional search results provided by HighBeam Research, LLC. © Copyright 2005. All rights reserved.