Composite clip showing how light pollution obscures the winter stars of the Northern Hemisphere. The clip is a composite of three images: the first was taken from a city with a ten second exposure, the second was taken in the country with a 180 seconds exposure, and the third was taken from the Roque de los Muchachos observatory on La Palma, Canary Islands, with a 600 second exposure. The dramatic effect of light pollution is clearly seen. In the city sky, the lights hide many of the stars, with even the brightest star in the night sky, Sirius faint at bottom centre. Images taken from Germany, looking south.