International Dark-Sky Association


The International Dark-Sky Association is a United States-based non-profit organization incorporated in 1988 by founders David Crawford, a professional astronomer, and Tim Hunter, a physician/amateur astronomer. The mission of the IDA is "to preserve and protect the night time environment and our heritage of dark skies through quality outdoor lighting."
Light pollution is the result of outdoor lighting that is not properly shielded, allowing light shine into the eyes and night sky. Direct light that shines into the eyes is called glare, and light directed into the night sky above the horizon causes skyglow. Lighting can also cause light trespass when it enters areas where unwanted. IDA was the first organization in the dark-sky movement, and is currently the largest.

Principal approach

IDA's principal approach is to raise awareness about the value of dark, star-filled night skies and encourage their protection and restoration through education about the problems and solutions, including outdoor lighting practices that create less light pollution. In 2011, the organization had about 5,000 members in 70 countries.

International Dark Sky Places

To promote awareness about the issues, the IDA has an International Dark Sky Places program that aims "to protect locations of exceptional nighttime visages for future generations."

International Dark Sky Parks

To promote the use of responsible outdoor lighting that minimizes light pollution, the IDA offers a Fixture Seal of Approval program. The program provides objective, third-party certification for lighting products that minimize glare, reduce light trespass and don't pollute the night sky.