On Thursday, August 23, 2018 at 10:35:18 PM UTC+1, Mike Collins wrote:
Gerald Kelleher wrote:
The glimpse of polar dawn presently is both unique and beautiful within 4
weeks of the first appearance of the Sun -

https://www.usap.gov/videoclipsandmaps/spwebcam.cfm

Sometimes no words can approach observations and perhaps the long polar
dawn is one of them.



It’s just another dawn.

It is a singular dawn that happens each orbit at the South pole around this period of the Earth's orbit until the Sun eventually comes into view on the September Equinox for the one and only time this year. Right now that polar dawn is spectacular due to a distinct surface rotation as a function of the Earth's orbital motion where the entire surface of the planet turns parallel to orbital plane .

That line of rotation is represented by the broken line coincident with the orbital plane as it carries the polar latitudes and everywhere else in a circle -

http://afewbitsmore.com/img/2015_ecliptic.png

Within a few weeks the South pole will turn through the circle of illumination and this is why there is the extended polar dawn presently and a sight that is new to me, at least the dawn colors -



https://www.usap.gov/videoclipsandmaps/spwebcam.cfm