When we used to live on the highveld in  South Africa bright blue skies without a cloud in sight where the order of the day during winter.  In reference to a Perry Rhodan story (a German scifi series, published in pulp fiction form) we used to call it “das blaue System” (the blue system – a defense shield around planets which manifested by bright blue skies without any colour gradient).  How can I not use the photo of this aircraft with the “Star Wars” logo blazoned across it to illustrate this idea?

Contrary to popular belief, we have blue system skies even in Germany.

For A Photo a Week with the theme blue.

More blue or blueish photos are linked here.