The Great World Wide Star Count

The following sun and moon data for Oct. 23, 2008 is provided by the United States Naval Observatory.

Sunrise: 7:24 a.m.

Sunset: 6:20 p.m.

Moonrise: 2:02 a.m.

Moonset: 3:38 p.m.

Moon phase: The moon is waning crescent with 26 percent of the visible disk illuminated.

Schoolchildren, families, and citizen scientists around the world will gaze skyward after dark from Oct. 20 to Nov. 3, looking for specific constellations and then sharing their observations through the Internet. The Great World Wide Star Count, now in its second year, helps scientists map light pollution globally while educating participants about the stars.

And although the program is already underway, it is not too late for Pagosa area skywatchers to begin — stargazers can record their observations on just one night, or multiple nights throughout the duration of the event.

The Great World Wide Star Count is free and open to anyone who wants to participate. The project is organized by the Windows to the Universe project at the Boulder, Colo.-based University Corporation for Atmospheric Research (UCAR), in conjunction with planetariums and scientific societies across the country and abroad. Funding is provided by the National Science Foundation.

“The star count brings families together to enjoy the night sky and become involved in science,” said Dennis Ward of UCAR’s Office of Education and Outreach. “It also raises awareness about the impact of artificial lighting on our ability to see the stars.”

The 2007 star count drew 6,624 observations taken on all seven continents, and organizers expect the number of participants to double this year. UCAR used last year’s observations to generate maps of star visibility across the United States and around the world. The results show a strong correlation between development and a lack of night sky visibility.

Next year, the star count will be included in a cornerstone project of the 2009 International Year of Astronomy, a global effort initiated by the International Astronomical Union and the U.N. Educational, Scientific, and Cultural Organization to promote interest in astronomy.

How the count works

Participants in the Northern Hemisphere will look for the constellation Cygnus, while those in the Southern Hemisphere will look for Sagittarius.

With the constellation located, participants will then match their observations with magnitude charts downloaded from the Great World Wide Star County Web site:

The Great World Wide Star Count Web site also contains more information about the event, including instructions for locating the constellations and reporting findings, and other astronomy related links.

Participants may make observations outside their homes or go to less developed areas where more stars are visible. Those in overcast areas who cannot see stars will be able to input data about cloud conditions instead.

Observations can be made outside a participant’s home or from a less developed area where more stars are visible. However, which ever route one chooses, the participant must know the longitude and latitude of the viewing location.

Bright outdoor lighting at night is a growing problem for astronomical observing programs around the world. By searching for the same constellations in their respective hemispheres, participants in the Great World Wide Star Count will be able to compare their observations with what others see, giving them a sense of how star visibility varies from place to place. The observers will also learn more about the economic and geographic factors that control light pollution in their communities and around the world.

Although the Great World Wide Star Count will utilize world-wide observations of Cygnus and Sagittarius for baseline data, another litmus test for gauging light pollution is whether or not the Milky Way is clearly visible in your viewing location.

Research as of 2001 indicates that about half of European residents and two-thirds of Americans cannot see the Milky Way from their home. In addition, researchers estimated that about one in five people worldwide live in a place where the night sky is too bright to identify the Milky Way. And worse, astronomers found that 99 percent of the U.S. and European populations live in areas considered light polluted.

Although some sky glow is natural, such as the faint glow from aurora, starlight that is scattered by the atmosphere, and zodiacal light (sunlight scattered off interplanetary dust particles, it is hardly enough to hinder one’s observations of the night sky. However, a poorly-designed, or poorly placed flood light, security light or street lamp can do much to obscure one’s view of the night sky. For example, researchers say the night sky in a contemporary suburb is about five to 10 times brighter than the natural sky glow; while the night sky in a large city may be 25 to 50 times brighter than the sky in a remote area.

“Last year’s results showed a strong correlation between dense development, where there is a lot of light, and a lack of star visibility,” Ward said. “Without even being aware of it, many of us have lost the ability to see many stars at night. Part of our goal is getting people to look up and regain an appreciation of the night sky.”