The universal experience, awesome and inspiring of star gazing questions our consciousness and lets us feel a mysterious connection that links us to the Universe. Giving us a sensation of infinity and eternity, the nocturnal sky’s performance links us to our earliest ancestors. However seemingly unchanging, this priceless cultural heritage is today in danger of disappearing and many people who live in the heart of cities have never seen the beauty of the Milky Way, nor the thousands of stars shining on a dark moonless night.
Up to the 19th century, nocturnal lighting was provided by the moon, torches and small lanterns. Since then, with the advent of gas and later electricity, nocturnal lighting has become more permanent and widespread, with the result that light pollution has slowly emerged. Light pollution can be defined as any modification of the natural light environment, and any sort of nuisance provoked by artificial light on the sky visibility, wildlife, ecosystems and health.
Today, men and women live and work as well at night than during the day, and it has become essential to light cities. Since relatively low cost of energy has never facilitated definition and implementation of good lighting practices, we are now faced with a dramatic increase of lighting, over and above the simple need to see and be seen.
Without considering the reasons why we would want to light to such a level that there is practically no difference between day and night, overuse of lighting is being justified by appealing to the satisfaction of a need for security, commercial promotions or showcasing architectural and natural heritage. Yet, not only does this happen to be a real waste of energy and money, but it has numerous negative impacts in many natural and human spheres.
It is therefore desirable to limit and reduce this useless and harmful waste that is light pollution so that it will be possible to recover and preserve our invaluable cultural heritage... dark starry skies.