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sundial at South Pole



 
 
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  #1  
Old December 1st 18, 04:21 PM posted to sci.astro.amateur
Gerald Kelleher
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Default sundial at South Pole

https://www.youtube.com/watch?v=pnuLTeHB3yU

There is only one day/night cycle at the South Pole with Polar noon in 3 weeks on the Solstice. The residual daily rotation at the South Pole still captures daily noon even though technically rotational speeds reduce to zero from a maximum speed of 1037.5 miles per hour at the Equator.

Like everywhere else on the planet, the Polar sundial will register the changes in the time for each 360 degree revolution of the shadow around the gnomon (flag pole) reflecting two surface rotations, one daily where the normal experience of daylight/darkness is absent and the other orbital where there is just one daylight/darkness cycle each year.




  #2  
Old December 2nd 18, 09:06 PM posted to sci.astro.amateur
Gerald Kelleher
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Default sundial at South Pole

It genuinely feels good to spot the normal noon cycle fit inside the Polar day/night cycle with the ceremonial pole surrounded by National flags reflecting that fact -

https://www.youtube.com/watch?v=pnuLTeHB3yU

So we have a United Nations in a geographical sense where no one Nation has claim on the surface point where rotation reduces to zero yet all longitude meridians encompassing Nations emerge from that point on the Earth's surface.

These facts matter.




  #3  
Old December 9th 18, 10:47 PM posted to sci.astro.amateur
Gerald Kelleher
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Default sundial at South Pole

It is lovely to see one cycle of rotation fit inside a larger Polar day/night cycle as the shadow turn through a full 360 degrees -

https://www.youtube.com/watch?v=pnuLTeHB3yU

Who would call themselves an astronomer and not notice.
 




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