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Summary
DescriptionRetrogradation.svg
English: The file is a non-faithful hand redrawing of File:Retrogadation.png, adapted to look fine in a small image scale.
The image represents the apparent retrograde/backwards movement when an outer planet P is passed by tellus/earth T from the inside, i.e. at the time of opposition, while in main part of the time the planet appears to move progradely/forwardly. The yellow blob marked S in the centre of the small circle is representing the sun.
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Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue
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