CHAPEL HILL -- The crowd stares upward -- heads tilted back, mouths open -- at the brilliant night sky overhead. Thousands of sparkling stars wink down from above. The Milky Way's silver band arches overhead, stretching from one horizon to the other.Unfortunately, this panoramic view of the heavens isn't real -- it's being projected onto the screen of the Morehead Planetarium and Science Center as part of "Our Vanishing Night," a program about light pollution. "We want to show people very visibly how the choices we make with our outdoor lighting affect the night sky," said Amy Sayle, an educator at the planetarium.Sayle begins the program by demonstrating a light-polluted view of the night sky that most Americans are used to seeing at home. You can hardly see any stars in the hazy, orange sky created by poorly designed outdoor lighting.After pointing out the few constellations visible, Sayle switches the view to a sky without the extraneous lighting. As thousands more appear, a collective murmur runs through the audience. A child in the back row whispers loudly, "Wow, look at that, daddy."The problem with light pollution isn't just that it washes out our view, it also consumes lots of energy. "The amount we waste is more than the entire energy consumption of some small nations," Sayle said.About 30 percent of all lighting in the United States is wasted, according to the International Dark-Sky Association. The IDA estimates that squandered energy costs Americans more than $10 billion annually.Some people install extra lights around their house because of security concerns, Sayle says, but too much lighting can be counterproductive. "It could keep you from seeing the mugger that's hiding in the shadows," she said. "If you're interested in true security, it's actually better to properly shield the light so that it's aimed down."Excessive lighting can also have serious ecological effects, says Travis Longcore, science director for The Urban Wildlands Group and co-author of the book "Ecological Consequences of Artificial Night Lighting.""The consequences range from death on the one hand to the exclusion of species in certain areas to behavioral changes," he said. "I like people to sort of put themselves in the place of another species. Think about a frog living in a wetland. You like the dark. You're safe from predators there."After Sayle's presentation, a walking tour around UNC's campus and Chapel Hill's downtown provided the opportunity to discuss better lighting practices. John Laetz, UNC's manager of electrical distribution systems, overviewed the university's plan for changing the lighting on McCorkle Place quad.McCorkle Place has 42 high-pressure sodium lamps that use a lot of electricity and create a lot of glare, Laetz says. The new lighting scheme will use metal halide lamps that are more energy efficient, reduce glare and provide more evenly distributed light. Although the number of lamps in McCorkle Place will approximately double, the university expects to cut its energy use there by about 10 percent, Laetz said.Some of those in attendance said they will now try to put what they learned to use at their own facilities. Richard Stevens, executive director at the New Hope Camp and Conference Center on N.C. 86 north of Chapel Hill, hopes to reduce light pollution at the camp. "I've been fortunate enough to see the sky in the wilderness," Stevens said, "and I miss that very much."