1. Every urbanite knows the bright lights of the city make it impossible to see the stars in a night sky. What most of us do not know is that those lights also may be making us sick. The cause is light pollution – the unearthly glow of billions of street lamps, security and porch lights, searchlights, office lights and signs – as people everywhere try to dispel the darkness of the night.
2. For the first time, light is being investigated seriously as a pollutant and a health hazard – a possible cause increased incidence of breast cancer, depression and other ailments.
3. In the most heavily urbanized regions, it no longer ever really gets dark. Satellite images reveal that in large areas of eastern North America, Western Europe, Japan and Korea, night has become a constant twilight. In a natural night sky, someone looking at the heavens should be able to see nearly 3500 stars and planets and the glow from the Milky Way, our galaxy. But in some brightly lit cities, the number of visible stars has dwindled to about a few dozen.
4. And for many wildlife species, light pollution seems to be as grave as environmental threat as bulldozed habitats and toxic-chemical dumping.
5. Lighting from office towers confuse migratory birds which fly into buildings lit up at night. Millions of birds in North America die from these crashes. Researchers have noticed since the 1980s that artificial lights along ocean beaches confuse millions of baby turtles. Observers say that the turtles instinctively crawl to the brightest thing on the horizon – normally the reflection of the moon on the sea. But where beaches are illuminated, baby turtles often crawl to the lit roads, where they are flattened by cars, or wander in circles on the beach. Once day breaks, they bake to death in the sun.
6. Sea turtles and birds are clearly in peril because of light at night, but scientists have begun to study whether human may share something of the same fate. Richard Steven,