Archivo: Huygens Systema Saturnium

Description: Top: Diagram showing how Saturn's appearance to us changes due the changing positions of the Earth (E) and Saturn as they orbit the Sun (G). Bottom: Huygens's observation of Saturn presenting its rings to us at their greatest inclination. (source)
Title: Huygens Systema Saturnium
Credit: http://www.sil.si.edu/DigitalCollections/HST/Huygens/huygens-ill55.htm
Author: Christiaan Huygens
Permission: This work is in the public domain in its country of origin and other countries and areas where the copyright term is the author's life plus 100 years or less. You must also include a United States public domain tag to indicate why this work is in the public domain in the United States. This file has been identified as being free of known restrictions under copyright law, including all related and neighboring rights.
Usage Terms: Public domain
License: Public domain
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