Thread: Polar astronomy
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Old March 5th 18, 10:30 AM posted to sci.astro.amateur
Gerald Kelleher
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Default Polar astronomy

On Sunday, March 4, 2018 at 8:29:08 PM UTC, Anders Eklöf wrote:
Gerald Kelleher wrote:

On Saturday, March 3, 2018 at 8:25:15 PM UTC, Anders Eklöf wrote:
Davoud wrote:

Bill:
Haven't you considered how much your choice to not take the time to
organize your topics into complete subjects that you then explain in a
systematic and through way - hurts your agenda?

He's a troll and his agenda is to reel in people like you. I would say
that he has been splendidly successful at fulfilling his agenda.

Reel in to what purpose?

As far as I can tell all he does is to explain what we all already know,
in a way that none of us understands. Quite a feat, really,

--
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to those whom I don't mind billing by the hour


These comments give me a lot of satisfaction as once you are shown how it

is done it all becomes common knowledge and easy. The illusory vs actual
loops of the planets owes a lot to astrophotographers and animation so
have no problem commending others for their efforts -

You miss my point:
We all know the fact you are trying to explain, but your explainations
don't help at all. In fact they are utterly confusing.
This should NOT give you any satisfaction at all.



Okay, I see you were referring to the direct/retrograde motions of the planets rather than the rotation responsible for the polar day/night cycle so I deleted the previous post.

The difference between the illusory loop of the slower moving planets and the actual loops of faster moving Venus and Mercury with the Earth's orbital motion providing the difference is an insight that came slowly, almost imperceptibly, with time.

I see the speed with which the difference had been adopted surprises even me for although many organizations are still unsure how to deal with the direct/retrogrades of Venus, at least they now isolate direct/retrogrades in an awkward way to the outer planets -

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

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

As direct/retrogrades are a result of the planets moving back and forth against the background stars, it should be no problem applying the same principles to Venus and Mercury as they run smaller loops around the Sun from our perspective so the Earth's orbital motion doesn't contribute to their direct/retrograde motions.

https://www.youtube.com/watch?v=MdFrE7hWj0A

As far as I am concerned the explanation would work amazingly well with VR and it should be done by a large organization like the space agency but otherwise anyone with a talent can do the job. This "we all know the fact" is meaningless as an internet search of direct/retrogrades of Venus will throw up astrological websites exclusively or focus on the planet's rotation whereas orbital motion as seen from Earth is being considered.