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Arc inversion



 
 
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  #1  
Old May 25th 17, 09:46 AM posted to sci.astro.amateur
Gerald Kelleher
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Default Arc inversion

It will be one of the trickiest topics in astronomy however when a lot of perspective debris is cleared and imaging is allowed to dictate a narrative, a clear idea should emerge . Today there is a lot of good imaging mixed up with poor conceptions which makes it difficult to generate descriptions without observers falling into old traps as the perspectives relies on two separate rotations affecting how we see the path of the Sun throughout the seasons.

The current narrative expresses a false perspective based on a tilting Earth where observers see greater and smaller arcs with the greatest arc at the June/ December Solstice depending on what hemisphere is being used -

http://www.mstworkbooks.co.za/natura...01-gd-0020.png


The actual path of the Sun is far,far more interesting in creating inverted arcs with the change more pronounced towards polar latitudes and flatter towards the Equator.

The only imaging available is spoiled by the wandering 'analemma' Sun so only the first 40 seconds of the time lapse is valid -

https://apod.nasa.gov/apod/ap161221.html

At the North pole presently where the orbital surface rotation dominates the Sun traces tighter and smaller paths until after the June Solstice when the circumference starts to expand once more.

At the Equator the Sun's path is always flat but varies where the Sun appears and sets.

The analemma nuisances don't stand a chance of appreciating the subtleties given that they can't manage to associate the daily arc of the Sun each weekday with one rotation.



  #2  
Old May 25th 17, 09:38 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Arc inversion

After consideration using the EPIC time lapse it would appear that the seasonal arcs of the Sun would not be flat however the polar arc would be absent unlike latitudes away from the Equator which would give greater polar influences.

https://www.youtube.com/watch?v=CFrP6QfbC2g&t=66s

Easy enough to envisage the tighter and tighter circles towards the December Solstice on Antarctic Continent but it is such a wonder journey that has yet to begin and I leave it for observers to pursue. The curvature of the Earth supplies the observed arcs and the changes seen not only seasonally but for different latitudes.





  #3  
Old May 27th 17, 09:22 AM posted to sci.astro.amateur
Gerald Kelleher
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Default Arc inversion

What makes the Sun's seasonal path so understandable is the changing relationship between the daily and orbital rotations so it is hoped that the people who created the EPIC time lapse can apply longitudes to the daily rotation while creating orbital latitudes where the polar points are seen to turn parallel to the orbital plane. The familiar arcs with a flat intermediary at the Equinoxes (for all points outside the polar surface points) is a wonderful point of departure for so many topics.

The flaw in current perspectives is certainly a tendency to put the observer at the center while leaving the horizon undefined even though there is just a handful of miles to opposite horizons and indeed the space agencies never bother to move to the level by which the EPIC images are analysed in a reasonable way.

https://www-istp.gsfc.nasa.gov/starg...s/Sunpath2.gif

http://www.morehead.unc.edu/Shows/EM...27s%20Path.jpg


The length of time an area spends in solar radiation is far more relevant than the angle of incidence however, as seen in the graphics above, observer's can't even get the apparent arcs of the Sun right which is dismaying to say the least.

The opposite of being inspired and inspiring is to be uninterested and uninteresting and unfortunately our era, despite amazing imaging and observing tools, is plagued with the latter.



  #4  
Old May 29th 17, 09:13 AM posted to sci.astro.amateur
Gerald Kelleher
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Default Arc inversion

One of the loveliest perspectives of the Sun's path at either poles (gained through the Youtube comment section) is that the Sun is seen to move from left to right at the North pole -

https://www.youtube.com/watch?v=vJe_SVgFBh0

And from right to left at the South pole -

https://www.youtube.com/watch?v=okw6Mu3mxdM

At the Equinox when the Sun comes into view for the first time and its path circles the horizon, it draws attention to the limitation of celestial sphere observing but equally brings into sharp focus the orbital surface rotation where the circling covers more and more surface area away from the North pole presently as the area where the Sun is constantly in view expands out to the Arctic circle.

From observer to horizon is only a handful of miles and RA/Dec observers have difficulties adjusting between their local observations and those on a planetary scale.
  #5  
Old June 8th 17, 09:16 PM posted to sci.astro.amateur
Gerald Kelleher
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Default Arc inversion

It is one thing to ignore many of the topics which translate observations from a moving Earth into cause and effect, the partitioning retrogrades, the dual rotations of the Earth responsible for their respective day/night cycles or many other topics however to get even the observations themselves wrong is of a different and more dismal level.

The Sun's path across the seasons where the daily and orbital motions combine generate the asymmetrical mirror arcs across the orbit of the Earth with the equinoxes being the dividing line hence the flawed notion that the difference between summer and winter is the size of the arcs, both running parallel with each other is going to be false -

https://www-istp.gsfc.nasa.gov/stargaze/Sunangle.htm

http://podcast.sjrdesign.net/images/024_SunPathDay.jpg

The problem with the last image is that from horizon to observer is not more than a handful of miles whereas the distance travelled by the observer each weekday from exiting the circle of illumination at dawn and entering it at sunset can be thousands of miles depending on latitude. The path of the Sun is captured by curvature of the Earth as the Earth both turns in a circle daily and as the relationship is changed by the orbital surface rotation, the one responsible for the polar day/night cycle.

There is certainly challenges but they are productive challenges so while many ran from the forum once something more substantial showed up and the others simply carry on ignoring this type of astronomy, it must be apparent to others that there is no real facility to expand on the narratives and that is a great shame.

 




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