The Great World Wide Star Count

October 9 – 23, 2009

During the Great World Wide Star Count, citizen-scientists of all ages will gaze skyward in October 2009, helping map light pollution around the world.

What can you see when you look up at the nighttime sky? Do you see stars, constellations, satellites, or the Milky Way? For many people around the world, the Milky Way is something known only through books and pictures, not something visible in their nighttime sky. Astronomers have long known that light pollution impairs our ability to clearly see the night skies and now the general public is also experiencing this phenomenon. Light pollution is often described as an undesirable byproduct of our industrialized civilization. It is a broad term that refers to multiple problems, all of which are caused by inefficient, annoying, or arguably unnecessary use of artificial light.

Students at Erie High School in Colorado Participating in the 2007 GWWSC
Students at Erie High School in Colorado Participating in the 2007 GWWSC (permissions pending)

Recognizing the interest and concern regarding the decreasing quality of our night skies, UCAR’s Windows to the Universe launched a new citizen science project in October 2007, The Great World Wide Star Count. This Windows to the Universe program is an international citizen-science event that encourages everyone, astronomers and non-astronomers alike, to measure their local light pollution and report their observations online. The Great World Wide Star Count is designed to raise awareness about light pollution as well as encourage learning in astronomy. No prior experience is necessary—all information needed to participate is on the Star Count Web site, along with a downloadable activity guide available in eight languages. All observations will be available online via Google Earth and as downloadable datasets.

Observations from Boulder County, Colorado overlaid on NASA's "Earth City Lights"
Observations from Boulder County, Colorado overlaid on NASA’s “Earth City Lights”.

The Great World Wide Star Count is an engaging project for teaching about the impact of artificial lighting on local environments and in raising awareness about the ongoing loss of people’s ability to study or simply enjoy the night sky in many parts of the world. Participants can explore the different light sources in their community learning the relationship between science, technology and their society, as well as investigate the economic and environmental impacts of light on a local and global scale.

In the first two years, more than 8,000 observations from over 65 countries were reported online. Please join us during the International Year of Astronomy to map the effects of light pollution world wide! The 2009 Star Count will take place from October 9-23.

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