Here is a short time-lapse clip of Düsseldorf's night sky. (contains some interesting features like planes, satellites and iridium flares)

This video is a composition of about 1.200 pictures taken with a Canon EOS 60D with a 50mm f1,4 lens. Each picture was exposured for 10s at an ISO of 250 and f1,8. Timewise it spans the night of Sep, 28th 2014 beginning at 1:20am till about 6:00am.

As mentioned earlier here are some of the special features:

Two satellites chasing each other very closely