Northern (de)lights

In Sunday evening I received some of the first aurora alerts of this autumn from the Finnish Meteorological Institute to my email. The values looked promising, even higher than in the more northern parts of Finland. So, the only chance for me was to go out with my camera and tripod. The show was already on with a high intensity. This is one of 45 exposures I took during about 75 minutes. The warm tones of the birch leaves were caused by street lights with different colour temperature.