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Where have all the stars gone?

Astronomer wants to bring back the night

POSTED: March 5, 2008 5:01 a.m.


Your grandfather probably remembers looking up at night and seeing the sky split by a translucent band of white light.

That’s the Milky Way, the galaxy in which the Earth is located. But unless you live in a remote area, chances are you’ve never seen it.

Astronomers say "light pollution" from cities is making it increasingly difficult to see objects in the night sky, even in rural communities. But over the next two weeks, you’ll have an opportunity to do something about the problem.

Robert Webb, a naturalist and astronomer at Elachee Nature Science Center, is inviting residents to take part in the international GLOBE at Night event, scheduled for Monday through March 8.

"It’s a citizen science project, kind of like the bird count," he said.

Last weekend, people all over North America participated in the Great Backyard Bird Count, submitting online checklists of birds seen in their neighborhoods.

Now, Webb is asking people to count stars.

GLOBE participants will simply go outside on a cloud-free night and count the number of stars they see within the "hourglass" formation of the constellation Orion.

The fewer stars they can see, the greater is the level of light pollution at their location. Observations will be sent in from all over the world to the project’s Web site,, giving atmospheric scientists a picture of light pollution around the planet.

Last year, 8,491 observations were submitted from 60 countries. The program’s sponsors, which include NASA and the National Science Foundation, hope to double that number this year.

Webb said all the details on how to participate can be found online. But he’ll also be offering a free kickoff event tonight from 7 to 8:30 at Elachee.

"First we’ll do a little talk about light and how it affects people and animals," he said.

Excessive nighttime light isn’t merely an annoyance. It can harm wildlife by confusing their perceptions of night and day, causing animals to alter their reproductive and feeding behaviors.

After a discussion about light pollution, Webb will use visual aids to demonstrate how to count the stars in Orion.

"Then I’ll show people how to use the computer to find their latitude and longitude," he said.

In order for an observation to be meaningful, scientists have to know exactly where the person was when they were counting stars. The GLOBE Web page has a link to a site where you can calculate your geographic position.

Webb will also show people how to enter their data online. For those who can’t attend tonight’s session, he has compiled all the instructions in a pdf file.

Weather permitting, he’ll then take participants outside to practice counting stars. But they can’t start doing official observations until Monday.

Webb recommends finding the darkest area of your yard and "standing out there for at least 10 minutes to let your eyes adjust (to the darkness)."

Another tip: At night, you can see better with your peripheral vision than by looking straight ahead. Webb said you’ll see more stars if you look to the side of Orion rather than directly at it.

He believes if light pollution obscures our view of the night sky, we’ve lost another important connection to the natural world.

"A lot of people may not care, but it’s part of our human history," he said.

Some communities, especially in the desert Southwest, have passed ordinances to preserve the darkness of the night sky. These laws usually require outdoor lighting to be directed only toward the area it’s intended to illuminate, rather than sending a lot of glare up into space.

Like most of Georgia, Hall County doesn’t currently have a light pollution ordinance. Webb hopes someday Georgia officials will take the problem seriously, especially since more efficient lighting could also conserve electricity.

"Light should be pointed downward, so the energy isn’t wasted," he said.


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