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Old May 26th 18, 06:48 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Illusory loops vs actual loops.

https://apod.nasa.gov/apod/image/150...peach_2504.jpg

Unlike the faster moving Venus, the slower moving Saturn doesn't show phases as the relative distance, size and period of our planet to Saturn's traits prevent anything only the occasional periodic shadow cast on the ring behind the planet.

The changes in the orientation of that planet's ring does change, not as an illusion as with direct/retrogrades loops seen from Earth but rather the change belongs to the planet itself as a function of the planet's orbital motion. Uranus too has equatorial rings which change their orientation to the Sun as a function of its orbital motion even though that planet is so much further from the Earth and the central Sun -

https://news.nationalgeographic.com/...icture_big.jpg

It is a pleasure knowing what is illusory from what is actual, not only with direct/retrograde motions of the planet as seen from Earth but also individual traits of the planets themselves.