The reflected light of a lunar day/night cycle within the polar day/night cycle doesn't require anything more than a brief consideration of the moon's motion around the Earth each month and it really is enchanting -

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

To see something happening in real time is truly special and an indication of whether people are comfortable living with 21st century imaging and the conclusions and insights drawn from these observations.

On any given day there are motions to account for and especially the motion going on beneath the feet of humanity and separately the planet's orbital motion through space and around the Sun. In this clear perceptual air where experiences of the day/night cycle and the seasonal cycle make sense, the insights start to flow once more and break up the self-imposed celestial sphere shell humanity acquired from people a number of centuries ago.