"The International Dark-Sky Association has named the English Channel island of Sark its first 'dark-sky' island.
There are billions and billions of stars in the sky, but most people in the developed world can only see a handful of them because of light pollution. Street lamps, illuminated signs and floodlit monuments all send light into the atmosphere, obscuring the much fainter stars.
Some light at night is necessary for safety and possibly aesthetic purposes, but the International Dark-Sky Association has been trying to get manufacturers to make, and people to buy, lights that shine exclusively down, or at least don't leak any unnecessary light up into the sky. New street lights, pedestrian lights, security lights, even floodlights at sporting events have been designed to produce far less light pollution.
Light pollution is particularly bad in the United States and Europe. According to the National Park Service, two-thirds of Americans cannot see the Milky Way. And 99 percent of the U.S. population lives in areas that scientists consider light-polluted."