Experts say sky glow a problem in Southeastern Wisconsin
On a warm June night, look at the starry Wisconsin sky. Can you find the Big and Little Dippers? Where is the North Star? Does the night sky look the way you remembered it? Probably not, and the reason is light pollution or sky glow.
Light pollution is the brightness you see in the sky as you drive towards a city at night and is simply caused by too much and improper lighting. Much of the light from the streetlights, security lights and decorative lighting of our 24-hour society escapes into the sky and dims our view of the moon and the stars.
One way to measure sky glow is to compare it to the night sky’s natural background light. According to information from the International DarkSky Association, a typical suburban sky today is about 5 to 10 times brighter than the natural sky. In city centers, the sky may be 25 or 50 times brighter than the natural background.
“Light pollution is a general problem for astronomy,” said Douglas Arion, professor of Physics at Carthage College. “But, also for the general health and well being of everyone.”
According to a light pollution brochure put out by the University of Wisconsin-Extension, the United States wastes as much as $1 billion dollars a year on lighting that is ineffective for security, and simply lights the night sky and adversely effects nocturnal animals and migratory birds.
For astronomers, sky glow can significantly decrease the objects in our sky that can be seen and discovered. This is particularly true for backyard astronomers and students. Arion has to take his astronomy classes outside of the city to do telescope observations of Kenosha’s night sky.
“It’s not just an astronomy issue,” said Vivian Hoette, education outreach coordinator for the Yerkes Observatory in Williams Bay. “The idea of the whole sky becoming urbanized, we would loose being able to look up at the sky and that being a part of our environment.”
Yerkes Observatory is a research branch of the Department of Astronomy and Astrophysics of the University of Chicago. The 77-acre, park-like site provides laboratory space and access to telescopes for research and for educational programs. The showpiece of the observatory is a 40-inch refracting telescope. When they opened in 1897, it was the world’s largest telescope, and today it is the world’s largest refracting telescope.
Research at the observatory is still being conducted, and according to Yerkes’ Director Kyle Cudworth, the research is limited by the size of the telescopes rather than by the light pollution in the area. But, to prevent a deterioration of visibility in the future, the Yerkes Observatory has taken a proactive approach to fighting light pollution in Walworth County, an approach that may work in Kenosha County. The staff has written a municipal lighting ordinance that considers light pollution.
Williams Bay has already adopted the ordinance that was written to “regulate outdoor night lighting fixtures to preserve and enhance the area’s dark sky while promoting safety, conserving energy and preserving the environment for astronomy.”
Cudworth has presented it to other Walworth County towns and villages. He said he would also provide the ordinance to other municipalities as a model for writing their won light pollution prevention ordinances.
Arion has had meetings with state Sen. Bob Wirch for statewide solutions to the sky glow problem. But, no legislature has been proposed. County and City officials seem ready to tackle this issue, though no ordinances specific to light pollution are on the books in either municipality.
“We’re not there yet,” said John Roth, senior planner for the Kenosha County Department of Planning and Development. “But, as development occurs we will look at it under more detail.”
The most salient issue for zoning ordinances is light trespass. It occurs when lighting from a one property trespasses into an adjacent property. This can be because lights are too close to the property line or are poorly designed and directed.
“Years and years ago there wasn’t anything,” said Randy LeClaire, traffic engineer for the city of Kenosha. “Action was taken in the 80s, when new subdivisions were built, and they try to address it in new projects.”
LeClaire sites the lighting design at HarborPark on Kenosha’s lakefront as a classic exception to the city’s lighting policy. The streetscape has numerous historical lampposts with unshielded lights. The city has no plans to retrofit the lights with shields or to reduce the number of lights on at one time.
According To LeClaire, all of the new streetlights that are being installed on city streets are cut-off fixtures. This type of fixture concentrates the light downward. The light’s design has the bulb hidden in a fixture that is parallel to the roadway, so it eliminates glare. Glare is the annoying light that beams directly into your eyes from a bright bulb, especially when you are driving at night. It comes from fixtures that are poorly designed or improperly aimed.
The city currently rents 4,000 streetlights from Wisconsin Electric. Most of them are older glare-producing drop glass fixtures. But, according to LeClaire, as they wear out they will be replaced with cut-off type lights in response to the new light pollution concerns.
Cudworth also offers simple advice for homeowners who want to help prevent light pollution. “Shield your lights, so the light goes down instead of up; use no more light than you really need for the purpose; and turn them off when they are not needed,” he said.