Light excess doesn’t occur in cities only – it reaches remote locations, such as natural reserves, affecting animals and plants, and also humans.
The Biosfera TV programme, on RTP2, dedicated a episode to this topic, and Raul Cerveira Lima, of IA, Universidade de Coimbra and Politécnico do Porto, contributed to clarify the many implications of this output of human activity.
Learn more on light pollution on this brochure (PDF) produced by the International Astronomical Union.