Primordial Light: LIGHT POLLUTION

Chances are when (if) you think of pollution you think of air pollution, oil spills, pesticides in streams, and the like. There is a kind of pollution that is a less obvious nuisance. Light pollution is harmful to the quality of life and health of human beings and it is harmful to wildlife, especially birds, and to plant life. The irony surrounding light pollution is that while air pollution, oil spills, and such like are very expensive to clean up, industry, small businesses, governments at every level, and private individuals can save money by curbing light pollution. All that is required is for everyone to aim their outdoor lights where light is needed—the ground—and stop shining light into the sky and on other peoples' property. Directed light requires fewer fixtures and lower wattage bulbs, and that's money in the bank.

The night is supposed to be dark. In most of the United States and Europe, and in cities everywhere, it is not. Have you ever looked to the south on a summer evening and seen a broad and beautiful band of light stretching from the horizon, arching overhead, and disappearing in the north? Probably not. That would be the Milky Way—our home Galaxy—and you would know it well if we had dark skies.

Friends, this isn't rocket science. Remove a lampshade in your living room and turn the lamp on. Now face the lamp and try to read. Go into a dimly lit room and shine a flaslight into your eyes. When you are a passenger in a car at night, make it a point to stare directly at the headlights of a dozen or so oncoming cars, then look at the road in front of you. This is what we are doing to ourselves at night all over the world with glare from unshielded and improperly aimed electric lamps. Now you see the problem and the solution. Lamp shades direct light where it is needed and prevent the glare of bright lights from being seen directly. When you use a flashlight you shine it on the thing you want to see, not in your face. It makes perfect sense—put the light where it is needed. Yet unshielded and mis-directed light fixtures that are doing nothing but lighting birds' bellies and throwing glare onto adjacent properties and into motorists' eyes cost Americans an estimated $1 billion in wasted energy each year. Consider this nighttime photo of a house:

The owner of this house is convinced he needs these lights for security, the idea being that anyone trying to break into his house in the night will be seen. He's wrong on at least three counts. First, no one is looking at his house at 2:00 a.m. Second, if someone were looking at his house they would be dazzled by the glare from his spotlights and they would have virtually no chance of seeing an intruder moving about in the deep shadows. Third, how does throwing glare on a neighbor‘s property (light trespass) help to secure his property!? One can read a newspaper in an otherwise unlit area hundreds of feet from his house by the glare of his spotlights.

My neighborhood has nine houses, including mine. Each of them has improper outdoor lighting (but my outdoor lights are disconnected.) Four of the remaining eight houses employ outdoor lighting in such a way as to degrade the quality of my astrophotography—though, fortunately, it is not always turned on. Repeat this thoughtless lighting in millions of households and in uncounted parking lots, factories, small businesses, streetlamp installations, and one of the worst offenders, signs lit from below, in which over 90 percent of the light goes into the sky, and it's not difficult to imagine that it amounts to at least $1 billion a year in wasted energy. Considering the international political situation, can we afford that kind of waste?

There is more to this than my selfish desire to see the night sky. While we can put a price on the energy that is wasted by poor outdoor lighting, no one has been able to name the value of natural beauty to the human race. That it has value is apparent from the fact that humans began making art before they began building houses. We spend billions to preserve our national parks and monuments, but ignore the transcendent beauty that can be seen only at night. Also to be considered is the effect of poor lighting on wildlife, especially birds. Birds become confused in the presence of glaring lights at night and many die in collisions with overly lit buildings. Improper lighting interferes with the imporant diurnal sleep-and-wake cycle of many animals as well as plants. Considering that we could save a billion dollars a year by preserving the beauty of the night, while reducing the threat to plants and animals, I can think of no reason for not doing so—unless we are, as has been suggested in other contexts, a nation of self-absorbed sheep, too inwardly focused to notice what's wrong and, if told what's wrong, too complacent to stand up and say "That's not right. Let's fix it." Here's another image to consider:

Courtesy NASA and the NOAO

The reaction of most people upon seeing this composite image of the Earth at night is "It's beautiful!" Friends, every bright spot on this image represents wasted energy. This is an image of electric lights being directed into space, where they are not needed. If the Earth were properly lit at night, major cities would be barely visible from space, revealed only by the dim gray glow of lights directed downward at the ground and then reflected upward by dark-colored pavement. Light pollution would be a tiny fraction of what it is.

OK, you're convinced, and you're not a sheep. Now, what can you do? You can contact your municipal, county, and/or state works authority and review and question lighting ordinances. Write a letter to the editor. Best of all you can join and support the International Dark Sky Association, (IDA) where you will learn more about this problem and what can be done about it. The IDA makes available educational material, model lighting ordinances, infomation on suppliers of ecologically sound lighting fixtures, and many other educational resources. Join, become an advocate, and help bring back the 12 hours of ethereal beauty that we are missing every day!

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