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A better view of direct/retrogrades for Mercury/Venus



 
 
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  #1  
Old October 23rd 18, 05:15 AM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

I sometimes see people scramble to put observations in proper context and that is fine,at least up to a point. The wayward video commentaries of Venus/Mercury in direct/retrograde motion are being replaced by much better descriptions although they too have difficulties -

https://www.youtube.com/watch?v=wQQN...ature=youtu.be

About 5:30 minutes in he gets around to showing how the faster Mercury appears to move from Earth and does a fairly good job up to a point but like the other guy trying to explain the annual motion of the stars falls victim to older and less productive views. Both are linked btw.

The slower moving planets and their direct/retrogrades are gauged against a fixed stellar background -

https://apod.nasa.gov/apod/ap160915.html

This doesn't apply to the direct/retrogrades of Venus and Mercury as they overtake us at the point where they are directly between the Sun and the Earth and captured by rare transits events. The background stars too have to move in a line-of-sight observation due to the orbital motion of the Earth and this is where the video commentary on the direct/retrograde of Mercury falls down in the YouTube description above (even though it should be commended).

The old Sky and Telescope website had a great animated description of all the moving components but unfortunately that video commentary is no longer available -

https://www.skyandtelescope.com/obse...3-planetdance/

It is great to see direct/retrogrades move back centre stage after their emergence 500 years ago via Copernicus. Of course a cold mind and heart doesn't have what it takes to deal with the logical reasoning but then again these things never were for those people.



  #2  
Old October 23rd 18, 05:34 AM posted to sci.astro.amateur
palsing[_2_]
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Default A better view of direct/retrogrades for Mercury/Venus

On Monday, October 22, 2018 at 9:15:31 PM UTC-7, Gerald Kelleher wrote:

snip crap

Explain this...

http://www.nakedeyeplanets.com/mercu...b-may-2012.png

  #3  
Old October 23rd 18, 07:37 AM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

On Tuesday, October 23, 2018 at 5:34:19 AM UTC+1, palsing wrote:
On Monday, October 22, 2018 at 9:15:31 PM UTC-7, Gerald Kelleher wrote:

snip crap

Explain this...

http://www.nakedeyeplanets.com/mercu...b-may-2012.png


They don't want you posting these illusory loops of Mercury because it exposes everyone else as know-nothings while those outside this newsgroup have developed an appetite to explain the motions of Venus/Mercury even if they come up short (the short passage about 5:30 minutes in).

https://www.youtube.com/watch?v=wQQN...ature=youtu.be

The observed motions of the faster planets include phases and size increases/decreases and they can be gauged against a 'fixed stars' background like the slower moving planets by virtue that the bulk of the Earth's orbital motion is accounted for by the transition of the stars from left to right of the stationary and central Sun when viewing the faster planets.

If this is the way progress is made in this era then so be it but make no mistake about it, as a spacecraft makes its way towards the centre of the solar system where Mercury and the parent central Sun exists, real enjoyment comes from knowing how we see the planets move and the structure of the solar system.





  #4  
Old October 23rd 18, 07:46 AM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

That should be the faster moving Venus and Mercury cannot be gauged against the 'fixed stars' background as the slower moving direct/retrogrades of the outer planets are -

https://apod.nasa.gov/apod/ap011220.html

Unless the line-of-sight change in position of the stars close to the Sun are accounted for by the orbital motion of the Earth, it is impossible to make sense of the motions of Mercury and Venus as they run their smaller circuits around the Sun relative to the larger orbital circumference of the Earth.

https://www.universetoday.com/wp-con...T_edited-1.jpg



  #5  
Old October 25th 18, 10:39 PM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

I have often been surprised at how quickly people adopt the insights but like any summit to climb, it is how people get there rather than just being able to take in the view.

It shows in the previous video commentary from a few days ago when they put the Sun at the centre of Venus motions, correctly identify how it moves against the stars up to a point but misses out on the motion of the stars from left to right of the Sun due to the orbital motion of the Earth.

The same happened with differential rotation of the fluid interior across latitudes for the purpose of geological evolution in tandem with the explanation for the spherical deviation across latitudes.

Astronomical composition allied with cause and effect or just the sheer joy of recognising motions and structures can be hard won so that even seeing people try to give less than correct perspectives makes me smile.
  #6  
Old November 1st 18, 10:05 PM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

On the news this evening it reported that vandals broke windows of a Church in Ireland and the pain of the parishioners was felt across the airwaves but as my country has hopped on the secularist/empiricist bandwagon very quickly such events are inevitable.

I turned the channel to BBC 4 and that Cox chap was explaining how Galileo was the first to affirm the motion of the Earth around the Sun by using the phases of Venus as a guess, this too is vandalism to the principles of astronomy. So I turned to YouTube on the tv and there too was a documentary explaining how Galileo was the first to affirm a moving Earth in a Sun centered system using the motions of Venus (oddly moving in the opposite direction of its actual orbit).

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


I have seen many things over the years, people believing the moon also spins as it orbits the Earth, an Earth with a zero degree inclination and a pivoting circle of illumination, an inability to correlate one sunrise/sunset each 24 hour day with one rotation or indeed the dozens of other careless and silly stories that show no dignity or respect for our ancestors and their achievements.

Even Galileo when he did show the phases and size increases/decreases of Venus as a guiding principle for its motion around the Sun, he could not account for the planet's direct/retrograde motion. The principles are tricky and not as straightforward as the slower moving direct/retrogrades of the outer planets as the Earth's orbital motion is accounted for in a different way .

"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

People are seemingly intent in wrecking astronomy including the history of discovery so I come here and present the works of those astronomers like Galileo who achieved something while also demonstrating why their observations need modifications,adjustments and corrections. Not all people can have a zombie nature, even here, so for some they will eventually feel the strain of missing out on what is good and enjoyable expression of human intelligence and spirit.


  #7  
Old November 12th 18, 05:20 PM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

We see Venus and Mercury run circuits of our Sun in much the same way exoplanets can now be spotted transitioning from left to right of their parent star -

https://www.eso.org/public/images/potw1846a/

It should be possible now to dispense with the language of direct/retrogrades for the faster moving planets as a consequence of their back and forth motions against the background stars in their smaller orbital circumference while allowing the line-of-sight transitioning of the background stars from left to right of the Sun as a consequence of the Earth's orbital motion.

This allows an inclusive approach of our planet and the faster moving planets with a central and stationary Sun as a reference.

See how quickly things come together after starting with a blank page ?, of course not.
  #8  
Old November 12th 18, 05:22 PM posted to sci.astro.amateur
Gerald Kelleher
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Default A better view of direct/retrogrades for Mercury/Venus

https://www.eso.org/public/images/potw1846a/

That should be from right to left of the parent star just as we see Venus and Mercury accomplish the same motion in their orbital circuits.
  #9  
Old November 13th 18, 11:03 AM posted to sci.astro.amateur
Quadibloc
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Default A better view of direct/retrogrades for Mercury/Venus

On Monday, October 22, 2018 at 10:34:19 PM UTC-6, palsing wrote:

Explain this...


http://www.nakedeyeplanets.com/mercu...b-may-2012.png


It is true that the aparent motion of Mercury resembles the apparent motion of
Mars; there is an overall motion through the Zodiac, and there are retrogade
loops.

However, in the case of Mars, the overall motion through the Zodiac has the same
period as the real orbit of Mars around the Sun, which is about two years. So
the retrogade loops are an illusion, caused by the Earth's motion.

In the case of Mercury, the overall motion through the Zodiac has the same
period as the apparent motion of the Sun through the Zodiac... one *Earth* year.

Not 88 days.

The retrogade loops, therefore, are the result of us seeing, admittedly from a
constantly changing vantage point, the *real* motion of Mercury as it orbits the
Sun. Just as we can see the real motion of the Galilean satellites as they orbit
Jupiter.

The overall motion, with a period of one year, is the illusion that results from
the Earth's motinn. So for the inferior planets, the larger circle is the
illusion, and the retrogade loops are the reality, exactly inside-out compared
to the apparent motions of the superior planets like Mars and Jupiter.

I know this is difficult for you to accept, but it should be an obvious
consequence of your own astronomical knowledge - this time, however confused and
garbled his explanation might be, basically, this time, Oriel36 is actually
*right* about something astronomical.

John Savard
  #10  
Old November 13th 18, 11:10 PM posted to sci.astro.amateur
Jibini Kula Tumbili Kujisalimisha
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Default A better view of direct/retrogrades for Mercury/Venus

palsing wrote in
:

The 'reality' of
Mercury's motion is way beyond Gerald's capacity to learn,


I suspect that putting on pants is beyond his capacity to learn.

--
Terry Austin

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https://plus.google.com/u/0/collection/QaXQkB

"Terry Austin: like the polio vaccine, only with more asshole."
-- David Bilek

Jesus forgives sinners, not criminals.

 




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