Unfortunately, few people enjoy unspoiled and totally dark skies. For those who do, computer analysis can readily answer the question.

Over the entire celestial sphere there are 8,479 stars to that magnitude limit.

Of course, we couldn't see them all at once. Some stars will always be out of sight at a given location because they're located too far to the north or south and will always lie below the local horizon. New Yorkers, for example, can never see the Southern Cross. Other stars are not visible because of their proximity to the Sun, hence are above the horizon during daylight hours.

Because of all of this, the total number any person can see at any given moment is close to 2,500. Poets who talk of millions of stars are either using a telescope or theyre exaggerating grossly.

The situation is entirely different for locations severely handicapped by light pollution, such as within the confines of large metropolitan areas.

Dark-sky advocates say light pollution is the excessive or misdirected outdoor lighting that is threatening to destroy virtually all casual stargazing. Throughout much of the United States, for instance, millions upon millions of precious watts are wasted because poorly designed street lamps send a portion of their light into the sky.

Over the past two decades, the increase in this ubiquitous, overbright, garish lighting has so polluted our nighttime environment that some critics suggest even driving on some roadways has become dangerous because of excessive glare.

The majority of lights on our streets and highways are of the high-pressure sodium vapor variety. They are, to say the least, ugly, overly bright and waste energy.

The night sky is the next endangered natural resource. A generation from now, if the current siege of "light blight" goes unchecked, seeing the stars will be reduced to a museum rendition, with the artificial firmament of your local planetarium becoming our childrens only view of the universe.

Lets take the Greater New York area as an example. For those who live in its immediate suburbs, the limiting magnitude, or LM, is probably close to 4.0 (remember: the lower the figure of magnitude, the brighter the star). This corresponds to roughly 250 visible stars, or one-tenth the number that can be perceived under perfectly dark skies.

From the outer boroughs of New York City (Brooklyn, Queens, Staten Island and the Bronx), the LM is likely closer to 3.0, suggesting that at best, only about 50 stars might be seen at any one time.

And, from brightly-lit Midtown Manhattan, the LM is probably only near 2.0, meaning that from the heart of New York City one should consider themselves very lucky to see more than 15 stars at any one time!

But there are solutions to this problem. Light pollution can be controlled and even reduced, by several approaches: installing more efficient, properly shielded lighting fixtures; determining systematic criteria for how much lighting is needed in a given situation; perhaps even imposing late-night "curfews" on outdoor advertising signs.

The International Dark-Sky Association (IDA), founded in 1988, gathers and disseminates light pollution information and solutions. It has played a pivotal role in turning the tide in the light pollution war. The IDA is winning over key sectors of the nonastronomical public including government groups, sections of the lighting industry, and the electric utilities with argument that good lighting for astronomers equals energy savings and more attractive surroundings for everyone else.

The IDAs work is founded by nearly 10,000 contributing members.

You can do your part, by learning more about light pollution and the IDA, and by taking steps to reduce extra nighttime lighting in your own town and backyard. These steps may not only enable you to see the stars better, but could also save you money on electricity and help reduce the world's energy crises.