Thread: Polar astronomy
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Old March 8th 18, 11:14 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Polar astronomy

On Thursday, March 8, 2018 at 6:26:42 PM UTC, Bill wrote:


I can't think of any professional level endeavor where that his sort of
lackadaisical, sloppy, piecemeal approach would provoke anything but
scorn from any audience.


"This apparent erratic movement is called "retrograde motion." The illusion also happens with Jupiter and the other planets that orbit farther from the sun."

https://mars.nasa.gov/allaboutmars/nightsky/retrograde/

So much for scorn when they already make the distinction without promoting how direct/retrogrades of the faster planets play out against the slower moving Earth. That distinction first happened in this newsgroup so I shrug and enjoy the fact that they at least strive to make the distinction without filling in the details for Venus and Mercury which requires an entirely different approach.

I guarantee that any teacher who teaches their students the principles which distinguishes the illusory loop of Mars from the actual loop of Venus by analogy or by use of imaging will get a satisfaction rarely experienced. It is because the direct/retrograde modification is new that it gives the talented plenty of leeway to express the principles as they see fit.