LIGHT POLLUTION: WHEN THE NIGHT NEVER GETS DARK

MAN-MADE LIGHT FLOODS THE NIGHT SKY, BLOTTING OUT THE MOON AND STARS, AND GLARING THROUGH THE BLINDS.

Imagine a National Park where we permitted the scenic views to be needlessly polluted with man-made refuse to the point where we could only barely see the most prominent features. Subtle valleys and glades are filled to the brim, with only the greatest peaks rising above a sea of litter. Suppose further that this trashing of the environment was not intentional, but allowed to advance even though the alternative is less costly and would save other natural resources.

This park is not official, but also not imaginary - it's very real. And, it's in your backyard. More exactly, it is above your yard: It is the night sky.

The vista of the night sky is indeed being obscured by pollution - the flood of man-made light. Light from poorly designed outdoor lighting fixtures is filling our night sky with a sea of pale orange light that covers the dark between the stars, leaving only the brightest points of light visible through the murk.

Here is an experiment: Go up high in one of the wonderful new buildings defining the progressive skyline of Charlotte. Look down on the sparkling foam of light. Now consider this: Not one of the photons of light entering your eye was intended for your reception. In fact, look out from your yard - none of that light is helping anybody, either. These misguided and wasted rays go up and scatter off particles in the air to cause the sky to glow. It is not that stars seen in country skies are brighter; it's that your city sky is brighter.

A student of mine who visited a friend in Chicago found the nighttime to be quite disturbing. Why? Because there was no nighttime - it was essentially always day. She found that at night, in spite of black curtains, she could read by the light coming in the windows. We are not talking about a neighbor's annoying security light - we are talking about ambient light from the sky. Imagine a night that never gets dark.

``So what?'' you ask. ``What's the big deal? I don't look up much anyway.'' Exactly my point. We have become detached from yet another part of nature. We are distracted from the glory of the heavens and thoughts of its creation, focusing instead on the glare of our own humble inventions. As an astronomer I am professionally concerned with light pollution, yet I am more afraid of its impact on the general population. We can always find dark, remote sites for observatories, but what about the average citizen of the universe?

Are we suffering from Stellar Affective Disorder? Would the cities have less strife if hardened gang members could see the Milky Way? Would we all act more civil if humbled by the majesty of the stars? Would our children enjoy the security of a night light that will always remain familiar? Would we be drawn outdoors at night, away from the TV, perhaps to meet our neighbors? Does a real sense of community require the dome of the heavens? While this possibility may seem as remote as the stars themselves, I am not so sure that it is.

In our parks we provide litter cans in which to place our trash. We all agree that this is a good idea, and that by doing so the views remain clean and spectacular, and draw us into introspective thoughts. We come away from such visits better people - this alone is justification for the parks' protection.

We can also protect our night sky so that it may be enjoyed by everyone - city and country dwellers alike. The enemies of the night sky include cheap security lights sold at home supply stores, up-pointing sign lights, and the cobra-head or jelly-jar shaped fixtures specified by the Department of Transportation. Good lighting fixtures with full horizontal cutoff are available. Sadly, these are most often specified by architects simply because the unit looks nice in the daytime.

Are you trashing the park? Do you have a security light that burns all night? How many criminals do you think will forsake their life of crime because you installed it? Or, perhaps, will your fixture provide them better light to do their deed? If you are in a remote or rural area, does your light really help you or may it actually serve as a beacon to attract passersby to an otherwise unnoticeable home?

You can take steps to clean up the park. Replace your outdoor light with a fixture that has a full horizontal cutoff shield (available at electrical supply stores). Put the light on a switch and add an infrared sensor that will turn it on when it detects an intruder (or your car pulling up). If you have one of the poor fixtures provided at a premium cost by the electric company, have them remove it and install your own. It will cost less in the long run, and you are then in charge of your light pollution. Take the lighting of our park back from the incompetent rangers.

While it may seem unlikely that our social problems will disappear by reclaiming our dark skies, who can tell what would happen? Let's clean up the park and see the stars again. Perhaps we will then also see each other better, in the dark.