Dark skies need to be preserved to continue to inspire the present and future generations

It is now estimated that 83% of the people living on Earth live under light polluted skies. The light pollution is not just a problem for our cultural heritage but it also threatens remote mountain tops where there are major worldclass astronomical facilities. In addition to its impact on astronomy, there is convincing evidence that light pollution negatively affects ecological and biological systems such as birds, sea turtles, nocturnal animals, insects and various human biological systems that are important to our health and our well-being. The International Astronomical Union has established a recommended maximum tolerable threshold of light pollution for astronomical sites of about 10% above national background levels.