Understanding Astronomy is intended as an online text for introductory astronomy. At this time, however, only the first few chapters are complete enough to post here.
Understanding Astronomy is Copyright ©2010-2011 by Daniel V. Schroeder, and is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. This copyright and license apply to all text, source code (HTML, CSS, and Javascript), and illustrations that are not attributed to any other source. If you copy or adapt this work or any part of it, please include an attribution to Daniel V. Schroeder and a link to the original.
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