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Stars Up, Lights Down

Fall 2001 Newsletter

Light pollution has received increasing attention in the past few years. The year 2000 saw an explosion of awareness in the news media:

• Time — "Bag Those Beams," Jan. 31, 2000
• Audubon — "The Dark Side of Light," Mar. - Apr. 2000
• Science — "Astronomy and the Degrading Environment," Apr. 21, 2000
• The Economist — "Going, Going, Nearly Gone" (referring to the starscape) Sep. 9, 2000
• MacLean's — "Let There Be Dark," May 22, 2000

These are just a few of the articles printed on this subject within the past few years. I visited one web site, sponsored by the International Dark Skies Association (IDA), and counted over 35 newspaper articles throughout the U.S., just in the year 2000, devoted to the topic of light pollution and peoples' efforts to do something about it.

If you have lived in this corner of Illinois for more than a few years, you can't help but notice that light pollution has arrived. If you haven't noticed, step outside on any clear, moonless night and look at the horizon.

There should be stars twinkling all the way to the ground in every direction. Chances are that you will see not stars, but a halo of artificial light all the way around the horizon. In only ten years, 30% of the visible stars in my neighborhood have been whited out by this sky glow.

I can no longer see soft light of stars on my path, and the neighbors' glary lights have recently erased my view of the Milky Way. I know that many in our area have similar stories to tell. Well, so much for the bad news.

There is also good news: preserving starry skies is a win-win solution. It conserves energy, enhances visibility, and increases safety and security. It keeps the light out of the sky and on the ground, where we need it. By using fixtures that are shielded, low wattage, and pointed downward, the light beam is directed onto the object to be seen rather than horizontally into our eyes.

A good rule of thumb: If you can see the light bulb, it's poor quality light. The aim is to see illumination on the ground, but not the light source itself. Think of a shoebox turned upside-down with the light bulb tucked up inside-the beam will be directed downward. An unshielded light bulb produces glare which shines into our eyes and can blind us rather than help us see better.

This poorly-directed light actually decreases safety. It produces shadows and blind spots, is a real hazard for the pedestrian or driver and an ideal hiding place for a thief or vandal. Shielded lights produce uniform lighting without the contrast of glare and dark shadows.

An unshielded light bulb produces trespass, spillage of light beyond the property boundaries onto neighboring properties, where it probably is not wanted. Into the eyes of passing motorists, for example, or into a neighbor's bedroom window.

An unshielded light bulb produces sky glow, which not only decreases our ability to view the stars, but also wastes energy. According to David Crawford (co-founder of IDA), as quoted in Audubon magazine:

"One-third of our lighting is wasted because it shines upward or side-ways, illuminating nothing but the bottoms of birds and airplanes."

The article goes on to say this waste squanders the equivalent of 8.2 million tons of coal or 30 million barrels of oil each year in the U.S. So what can we, as individuals, do?

Plenty. Here are some specific solutions. Start with your own outdoor lighting. Shield your existing lights, if possible, or switch to light fixtures that are fully shielded. Kichler makes a fully shielded light for home use (model # 9022) which can be wall- or post-mounted. It costs about $50.

If you are beginning new construction, consider recessed canister lights that fit inside the overhanging soffit. Make sure the lens does not drop down below the horizontal level of the bottom rim of the canister, and the illumination will be good quality-uniform light directed downward onto the ground.

There are also canister lights readily available at home improvement stores which can be mounted on the side of your house. Use only the minimum wattage that will illuminate your sidewalk or driveway. A 25-watt light bulb inside a fully-shielded fixture produces adequate illumination.

Consider motion-sensor lights that turn on automatically when someone walks across their beam and shut off after a few minutes. If you have a dusk-to-dawn light, there are skycaps now available that fit over them to capture the light and direct it downward. They cost $45 (including shipping) and can be obtained through Outdoor Lighting Associates in Ames, Iowa (515-233-0117.)

Better yet, call the energy company that supplied the light and ask them for a more efficient light fixture. According to a July 1990 article in Sky & Telescope magazine ("The Battle Against Light Pollution"):

"A 175-watt dusk-to-dawn mercury-vapor lamp uses, with ballast, about 860 kwh of electricity and costs $69 per year to operate. A 35-watt, full-cutoff, low-pressure sodium fixture would cost less than $20 a year to operate and provide better light."

" ….every year some 240 pounds of coal or 20 gallons of crude oil are consumed needlessly by each such fixture."

Ask your light company if this is true, and if so, why? Demand more efficient lighting. Talk to your neighbors in a friendly way if you are bothered by their lights. IDA has excellent educational resources that can be printed at their website.

Turn off lights when not being used for outdoor activities! This is the surest way to save energy and preserve starry skies. Talk to your county or city representative. The Jo Daviess County Comprehensive Plan has now been finalized and adopted, providing for sound growth and development in our County. Goal 6 of this plan is to preserve the rural character and quality of life, and one of the provisions under this goal is protecting rural dark skies.

Point out the problems with poor quality lighting shining into motorists' eyes at car lots and gas stations because of floodlights, and ask what is being done to protect our dark skies. And, if you want to take a more active role, I am organizing a local chapter of the International Dark Skies Association, to be called Northwest Illinois Chapter of IDA.

The dues are $30 per year. Call me at (815) 777-1264 if you are interested in joining. Or, e-mail me. We'll put our heads together and see what can be done to preserve our stars. If every one of us does what we can with our own lighting, expands our awareness, and begins talking about this issue, we can preserve our rural nighttime beauty.

Wouldn't it be great if we could all walk outdoors some night soon and see stars up and lights down?

—Bonnie Garrity