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Direct/retrograde loops



 
 
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  #1  
Old February 9th 18, 10:21 AM posted to sci.astro.amateur
Gerald Kelleher
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Default Direct/retrograde loops

The geocentric astronomers up to the time of Copernicus saw that all planets would occasionally process a loop against the background stars -

https://apod.nasa.gov/apod/ap031216.html

Copernicus explained that this loop was illusory and due to the orbital motion of the Earth overtaking the slower moving planets as Jupiter and Saturn are seen to do as they fall behind in view -

https://apod.nasa.gov/apod/image/011...2000_tezel.gif

Unlike the illusory loops of the slower moving planets, the faster moving Venus and Mercury show actual loops around the Sun -

http://www.insideastronomy.com/uploa...0_7_128459.jpg

Their direct/retrogrades are simply a reflection of their smaller orbital circumference (compared to the Earth) and their faster orbital motion as they swing in front of the Sun and then move in the opposite direction behind the Sun.



  #2  
Old February 9th 18, 10:19 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Direct/retrograde loops

"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 1632, Dialogue Concerning the Two Chief World Systems


These men would have understood what was needed to partition direct/retrogrades by the faster or slower, the greater or small circumference and the many other different facets that account for our motion and those of the other planets around the Sun.

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

Either directly or using indirect analogies like Jupiter's satellites, the direct/retrograde motion of Venus is a function of a smaller circumference and a faster moving planet. The great unused proof for the Earth's orbital motion around the Sun as the stars transition from an evening to morning appearance with the Sun as a central reference completes a work that was started 500 years ago.

It is great that people will someday enjoy the full story and that is all that matters.
  #3  
Old February 9th 18, 10:47 PM posted to sci.astro.amateur
palsing[_2_]
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Default Direct/retrograde loops

On Friday, February 9, 2018 at 1:21:39 AM UTC-8, Gerald Kelleher wrote:

Unlike the illusory loops of the slower moving planets, the faster moving Venus and Mercury show actual loops around the Sun -

http://www.insideastronomy.com/uploa...0_7_128459.jpg


.... except they don't, actually. From this page...

http://www.nakedeyeplanets.com/venus.htm

.... we read...

"Direction & Altitude Diagrams (Horizon Diagrams) for the 2018 Evening Apparition [of Venus]

The following diagrams show an observer's Western horizon (from due South to due North) for latitudes of 55° North (a high-Northern latitude), 35° North (mid-Northern), the Equator and 30° South (mid-Southern). The path of Venus is plotted in the sky at 30 minutes after local sunset throughout the 2018 evening apparition with the planet's direction and altitude marked along the horizontal and vertical axes, respectively. Essentially, these diagrams show the same information as in the above look-up tables, but in an illustrative format, for the Equator and three intermediate latitudes...

http://www.nakedeyeplanets.com/venus...55n-a-grid.png

http://www.nakedeyeplanets.com/venus...35n-a-grid.png

http://www.nakedeyeplanets.com/venus...-eq-a-grid.png

http://www.nakedeyeplanets.com/venus...30s-a-grid.png

Do try and learn something for once, Gerald... I know it's hard, but try anyway.
  #4  
Old February 9th 18, 11:06 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Direct/retrograde loops

palsing

Unlike people who recognize the worth of a work when it is in front of them, it just doesn't happen here so when you encounter Galileo description of the direct/retrograde loop of Venus as an illusion due to the orbital motion of the Earth, you should pay attention to why the issue was difficult for the original Sun centered astronomers but not now.

The phases of Venus dictate not only size increases but also that the Sun is central hence the only permissible loop seen from Earth -

http://www.insideastronomy.com/uploa...0_7_128459.jpg

The intuitive faculties extend this to the role the Earth's orbital motion plays out in this scenario so it makes use of the Sun as a central reference for the transition of the background stars from an evening to morning appearance -

https://www.youtube.com/watch?v=eeQwYrfmvoQ&t=12s

Mathematical minds tend to squander intuitive insights although no person, not even you, are without some sense of perspective insight. You should leave these threads alone and stick with the giddy rotating sphere of stars that clouds the judgment of so many or that I have to hear some obligatory meaningless or worthless stock phrase or slogan.













  #5  
Old February 10th 18, 12:44 AM posted to sci.astro.amateur
palsing[_2_]
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Posts: 3,068
Default Direct/retrograde loops

On Friday, February 9, 2018 at 2:06:14 PM UTC-8, Gerald Kelleher wrote:
palsing

Unlike people who recognize the worth of a work when it is in front of them, it just doesn't happen here so when you encounter Galileo description of the direct/retrograde loop of Venus as an illusion due to the orbital motion of the Earth, you should pay attention to why the issue was difficult for the original Sun centered astronomers but not now.

The phases of Venus dictate not only size increases but also that the Sun is central hence the only permissible loop seen from Earth -

http://www.insideastronomy.com/uploa...0_7_128459.jpg

The intuitive faculties extend this to the role the Earth's orbital motion plays out in this scenario so it makes use of the Sun as a central reference for the transition of the background stars from an evening to morning appearance -

https://www.youtube.com/watch?v=eeQwYrfmvoQ&t=12s

Mathematical minds tend to squander intuitive insights although no person, not even you, are without some sense of perspective insight. You should leave these threads alone and stick with the giddy rotating sphere of stars that clouds the judgment of so many or that I have to hear some obligatory meaningless or worthless stock phrase or slogan.


"To realize that you do not understand is a virtue; Not to realize that
you do not understand is a defect."
- Lao Tzu
  #6  
Old February 10th 18, 08:06 AM posted to sci.astro.amateur
Gerald Kelleher
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Posts: 1,551
Default Direct/retrograde loops

". . . the ancient hypotheses clearly fail to account for certain important matters. For example, they do not comprehend the causes of the numbers, extents and durations of the retrogradations and of their agreeing so well with the position and mean motion of the sun. Copernicus alone gives an explanation to those things that provoke astonishment among other astronomers, thus destroying the source of astonishment, which lies in the ignorance of the causes." Kepler 1596, Mysterium Cosmographicum

This is the sole reason direct/retrogrades were never partitioned as they had to supply proofs for the old geocentric framework which predicts positions of celestial objects so well. Again, the value of the work doesn't rely on providing proofs within the old framework as that was the problem all along.

To break the old framework is a process where the phases of Venus dictate the direct/retrograde loop as a reflection of a faster planet and a smaller orbital circumference -

http://www.insideastronomy.com/uploa...0_7_128459.jpg

As the Sun is central and stationary it is no longer possible to use its annual perceived motion through the constellations,as Kepler does in the statement above, leaving the only possible perspective - the transition of the stars from an evening appearance (left of the Sun) to a morning appearance (right). It is already done but the people who created the animation don't know the historical value of their own work -

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

People should not feel uncomfortable with this new approach or try to put up some pretense as they drink from the same astronomical fountain that I do..





  #7  
Old February 12th 18, 09:08 AM posted to sci.astro.amateur
Gerald Kelleher
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Default Direct/retrograde loops

A genuine teacher would find it impossible not to teach their students how we see the faster moving planets closer to the Sun differently than the slower moving planets further out. One of the joys of life is bring up perspectives that make sense hence the saying of Galileo -

“You cannot teach a man anything, you can only help him find it within himself.”
― Galileo Galilei

If asked to explain why Venus displays direct/retrograde motion, there is no possible way to avoid the planet's phases as the planet runs an actual loop of the Sun -

http://www.insideastronomy.com/uploa...0_7_128459.jpg


There is a good reason why theorists oppose human space travel as they are not comfortable with space and our celestial neighborhood while those with higher reasoning in astronomical affairs would encourage visiting the new frontier as all societies are meant to do.



 




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