Chile participates in global light pollution study

GLOBE at Night, a project aimed at educating students about light pollution, grew out of a prototype project based jointly in Chile and the United States.


Students and teachers in 86 countries around the world are participating in a project to gather data on light pollution from their homes and submit it online. Chile has one of the highest participation rates in the global study, with 600 independent observations submitted this year.

The GLOBE at Night program, which began in 2005, was inspired by an initiative launched three years earlier by the National Optical Astronomy Observatory (NOAO), whose state-of-the-art facilities take advantage of clear night skies in the southwestern USA and northern Chile. The prototype project was designed to teach students about the physics of light and the dangers of light pollution in Chile and the USA respectively, and help them share data via annual videoconferences.

Analysing five years of mapping data collected, the GLOBE at Night project’s parent organization Global Learning and Observations to Benefit the Environment (GLOBE) can now track worldwide changes in light pollution while simultaneously raising awareness of the issue, particularly in the urban and suburban areas where most participants reside.

Working simultaneously to measure and educate about light pollution, GLOBE at Night will raise the necessary awareness to resolve the problem it measures.

The experiment itself is simple. Over a two-week period in March, participants observe the prominent constellation Orion nightly. Participants then compare the night sky overhead to a series of images available on the GLOBE at Night website depicting the stars at varying magnitudes of brightness.

After the weeks of observation, participants submit the image that most nearly matches their sky via an online database. This information is then compiled annually to create a world map of light pollution.

The Observatory’s program was picked up by GLOBE in 2005. According to Dr. Constance Walker, the director of GLOBE at Nighht who has been with the project from the beginning, it was the international aspect of the light pollution project that caught the organization’s eye.

In its first year the project gathered 3990 independent observations. In 2010 the number of independent observations reached nearly 18,000. While the majority of the 2010 data came from North America, Chile had one of the highest participation rates of the 86 countries that contributed to the project this year, with its over 600 independent observations only behind the United States, Puerto Rico and Poland. Chile also had the second highest number of participants per capita, second only to Puerto Rico.