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The Sky – We're Losing It

How many of society's problems are traceable, at least in part, to a loss of contact with nature and her systems? Do we waste resources because we don't appreciate their fragility or their limitations? Do we fail to protect the natural environment because the environment we know is mostly man-made? Do we fear things in nature simply because we don't understand them? Do we subconsciously devalue human life because we don't see it in the context of larger natural processes?

While you're pondering those deep questions, I have a specific concern to bring to your attention. We are losing contact with that most universal of natural resources: the night sky. A huge culprit is man-made lighting. I will mention the word pollution just once because it is how many amateur astronomers express the problem. Fred Schaaf [1992] defines it as excessive or misdirected outdoor lighting. Could we be destroying a resource and wasting power in one swell foop? I think so.

Putting some numbers on the problem, I estimate the number of stars visible on a dark night in Haverhill, New Hampshire, away from lights, is between two and four thousand [Schaaf, 1990]. With a nearby streetlight or a full moon up, the loss of visible stars is 70-90 per cent. How many stars could one see from a West Lebanon (NH) mall or even from downtown Woodsville (NH)? Comets Hyakutake and Hale-Bopp were not visible from these locales, and it is nearby concentrations of light, not distant urban areas, which are a problem for any rural or suburban region. A city twice as big causes twice the problem, but due to something called the inverse square law, a mall twice as close is four times the problem.

Stars are not the only objects we lose. The near ones are bright enough to observe with or without optical aids, even through local light sources. The much dimmer deep-sky objects such as star clusters, nebula, and galaxies, will simply disappear from view if trends to 'light up' continue. Currently, there are many of these sights awaiting anyone who looks up: traces of our own galaxy, the Milky Way; its closest neighbor, Andromeda, some two million light years distant; the rural outliers of our galaxy, the star clusters such as the Pleiades and the Beehive. Look closely and you will see objects which appear to be more than single stars. These become targets for those armed with binoculars. John Kozak [1988] writes that there are hundreds of objects to see with binoculars. Take this strategy one step further, and binocular sightings become suggested projects for a telescope, enabling the user to observe a 'wanna be' solar system or an exploded star. In all cases, these are objects that help us understand the natural processes in the heavens. They are galactic clocks, and they help to illustrate our common history and our common fate.

Anticipating cries of elitism and special interest, I would like to pre-emptively plead guilty. Lighting restrictions would help professional astronomers and those amateurs who can afford fancy telescopes, but I think all of us who live in the country, and who are able to see and hear, taste and touch what nature has on daily display, are in the elite; therefore, I confess to speaking for one of largest special interest groups in the world -- those of you who can look up and see the sky. Many sky events are very short-lived, and this is why amateurs are important. We outnumber the pros by a wide margin. Many significant discoveries are still being made, even in our in our high-tech era, by amateurs looking in the right place at the right time.

We do have conflicts of interests to work out. Some have a need to see where to walk at night, and some need to see what's coming down the road. Others don't want light shining into their eyes or into their houses. What can we do? We can discuss it and make sound decisions. There are ways to have outdoor light and not waste it. The type of light can make a difference. Low pressure sodium sources permit the greatest visibility and are cost-effective, while at the same time they are less damaging to sky observation than mercury or high pressure sodium lights [Schaaf, 1990]. More important is the method of shielding the light. Unshielded lights waste over half of the power they use, unless you have a need to see the bugs which fly above them. Some lights, though shielded above, could be more concentrated still, where light is needed, and not shine in anyone's eyes. Who said you can see better when the light is in your eyes? The best use, and least wasteful and damaging, is outdoor lighting that is fully shielded. All the light is directed downward. I believe this could eliminate ninety per cent of the sky watchers‘ problems. Go on, count yourself a sky watcher -- you’re eminently qualified.

We have unique advantages in this North Country of New England. We have a hotline to nature. Living in small towns, we have an easier time reaching common understandings (though I didn't say easy). We also have fewer commissions and less red tape to wade through when we see a need for action. The selectpersons and power company officials are our neighbors and they want to serve us. I have found both to be understanding and cooperative. If you think wasted outdoor lighting is a growing problem, and you don't like wasting money and electricity, please talk to them. If you need expert assistance in knowing more about lighting or developing policies, please use the link to the International Dark-Sky Association (IDA). We can keep our sky.


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