Star Constellations

I took the photo above in my backyard. It has quite a good view on several star constellations, like Cassiopeia(, also called 'the big W'), Ursa Minor (the little bear), Hercules and Draco. The brightest star in this picture is Vega. Vega is part of the star constellation lyria, which is unfortunately covered by a tree. Close to it would be the 'Cygnus' constellation(, also known as 'the swan'), but unfortunately the tree blocks the sight again. Ursa Minor is in the center of the picture and contains at its end the star 'Polaris' (north star), which lays almost exactly above the axis of the earth. That being the case, it seems like all stars would revolve around polaris; furthermore, it marks the direction of north.

Star trail pictures build on this little fact, that all stars seem to revolve around Polaris. Often photographs capture around 400 to a 1000 pictures in the exact same position with Polaris in the center (, or a different beneficial position) and then overlap all pictures. Sometimes, the artist goes even further and 'plays' with different opacities of pictures and create a comet star trail picture, which I am personally quite fond of.