Thread: APoD today
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Old November 8th 18, 09:22 PM posted to sci.astro.amateur
Gerald Kelleher
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Default APoD today

https://apod.nasa.gov/apod/astropix.html

At least people are learning how to describe and differentiate the illusory loops of the slower moving planets where the Earth overtakes them and thereby a central Sun is inferred. Copernicus switched the 365 day motion of the Sun between Mars and Venus with the 365 day motion of the Earth.

I assume that the direct/retrogrades of the faster moving planets require a certain courage but the closed loops ,phases and numerous other components make it fairly easy with familiarity -

https://www.popastro.com/images/plan...ary%202012.jpg

The final piece was constructed in this newsgroup where the transition of the stars from left to right of the Sun sets up the Sun as a central reference for the motions of Venus and Mercury so the minimal effect of the Earth's orbital motion is to delay the points which Venus and Mercury reach before turning in front of the Sun or behind the Sun.

The partitioning of direct/retrogrades using faster/slower motions or wider/smaller orbital circumferences will eventually make it into circulation so at last I can take a rest.