Light Pollution

The term Light Pollution refers to excessive and glaring artificial lighting, especially light that is scattered above the horizon.  This is a very serious problem for astronomers, because it can prevent them from seeing objects in space.

Light pollution also can impact day-night cycles of animals and may be linked to certain health problems.  Reducing light pollution helps preserve our starry night-time skies and can also reduce energy costs.

GLOBE at Night is a light pollution awareness program that has been on-going since 2006.  The program is managed by the University Corporation for Atmospheric Research and Colorado State University.  This program relies on ordinary people, not necessarily astronomers, to view and report on the brightness of stars that they see from their location on certain nights of the year.  There are five sessions planned for 2013. The next one is March 3rd - 12th.

The program consists of 4 simple steps.

  1. Find your latitude and longitude
  2. Find Orion or Leo between 8 pm and 10 pm.
  3. Match the number of stars that you can see with the charts provided.
  4. Report your observation.

During the last 7 years, people in 115 countries contributed over 83,000 measurements during the campaigns, making GLOBE at Night the most successful light pollution awareness campaign to date.

Packets for teachers and families are available at  You can also find information about how students can become Dark Skies Rangers, a program sponsored by the National Optical Astronomy Observatory.

Western Slope Skies is produced by members of the Black Canyon Astronomical Society.