NEW YORK - Night comes to Times Square, but not darkness. In the space of a few tight blocks, end-to-end billboards glow with bright lights. Marquees beam with the titles of the latest shows. Images dance on jumbo television screens in a kinetic display of kilowatt consumption.
This is a place to gaze at stars of the human variety. Anything celestial is lost in the milky haze that bathes the sky.
Times Square may be a dazzling extreme, but America likes lights. The country is so well-illuminated that astronomers say that only one in 10 Americans lives in a place where light pollution has not marred the beauty of the night sky.
The result is that in the nation's urban areas, far fewer stars are visible than in rural spots, and fainter objects, such as the Milky Way galaxy, small meteors and wispy nebulas, disappear completely.
But an unlikely coalition of professional and amateur astronomers, lighting engineers, energy conservationists and ordinary citizens is now prodding a growing number of local governments into actions intended to bring back at least some of the night.
This coalition of "dark-sky" advocates has persuaded many local governments across the country to install light fixtures that produce less wasted light. Cities big and small have adopted legislation aimed at controlling how businesses use lights - requiring, for instance, that billboards be lit from above, with lights pointing down. Some utilities are even distributing fliers warning their customers of the dangers of over-lighting.
"If we had our way, the whole world would still be well-lit," said Don Davis, president of the International Dark-Sky Association, which has 2,100 members in 70 countries. "But you wouldn't be able to see anything from space because all the light would be pointing down."
Municipalities that have enacted light-control laws include Tucson, Ariz.; Las Cruces, N.M.; Ames, Iowa; Atlanta; San Diego; and Kennebunkport, Me. State laws in Maine and Arizona regulate the kind of lighting that can be used on state-funded projects.
In recent decades, light pollution has increased dramatically as suburban development led to more highways and bigger shopping malls. Also, concerns about crime led to installation of bright floodlights in many areas.
But much urban light is wasted, shooting upward or sideways. That washes out the night sky. The light pollution of Los Angeles, for example, has limited the kind of observations that can be done at the nearby Mount Wilson Observatory with its world-famous 100-inch telescope.
Even from afar, the glow of city lights can interfere with astronomical work because so much current research involves the most distant and dimmest objects. An astronomer who studied light pollution in California cities estimated that the "sky glow" caused by light pollution from a metropolitan area with 1 million people would hamper scientific work at an observatory almost 70 miles away.
But concern over light pollution is not limited to professional astronomers. Many amateurs and others with only a casual interest in astronomy sense the loss of something important when man-made lights blot out the lights of the universe.
"Many of our members remember lying in the backyard and looking up at the stars when they were growing up," said Davis, a planetary research astronomer in Tucson. "And they want their kids growing up in cities like New York and Chicago and Los Angeles to be able to see the night sky without having to drive 50 miles."