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Old January 2nd 19, 12:34 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Resolution of the Galileo affair

The direct/retrograde motions of the faster moving Venus and Mercury are entirely different to the illusory direct/retrograde loops of the slower moving planets further from the Earth with their greater circumferences. All the same, there is a great satisfaction knowing that a community are coming around even without any attribution to the partitioning of perspectives -


"Put more plainly, pretend you're Earth, watching Mercury run around a track. As it runs its loop, it will start out moving from the left side of your field of vision to your right. Then, it rounds the corner and, although not moving backward, is now running from right to left. This analogy is oversimplified because it doesn't take into account the fact that Earth is also moving, but it gives a good idea of how this optical illusion plays out.
All of the planets exhibit apparent retrograde motion, although it plays out slightly differently for planets farther from the sun than Earth versus those, like Mercury, that are closer to the sun than Earth." CBS news

https://www.youtube.com/watch?v=3VVCiPp67vI&t=195s

https://www.theplanetstoday.com/solar_system_video_1996


Galileo nor any of the original Sun centred astronomers made the distinction in accounting for direct/retrograde motions for very specific reasons -

" Now what is said here of Jupiter is to be understood of Saturn and Mars also. In Saturn these retrogressions are somewhat more frequent than in Jupiter, because its motion is slower than Jupiter's, so that the Earth overtakes it in a shorter time. In Mars they are rarer, its motion being faster than that of Jupiter, so that the Earth spends more time in catching up with it. Next, as to Venus and Mercury, whose circles are included within that of the Earth, stoppings and retrograde motions appear in them also, due not to any motion that really exists in them, but to the annual motion of the Earth. This is acutely demonstrated by Copernicus . . . " Galileo

I am among people who can be bullied into silence while the rest of the world just gets on with framing the insights in a better, if slightly deficient way.