Light pollution is when the lights from metropolitan areas wash out the night sky. In contrast, a sparsely populated area such as Big Pine Key in Florida makes an excellent place for stargazing. As one expert writes, “It’s the only place in the continental U.S. where stargazers can spy the Southern Cross and other features familiar to equatorial dwellers.” How exactly does light pollution happen? According to the Astronomical Society of Las Cruces, most fixtures send light out in all directions rather than where it is most needed — at the ground. Light pollution-control advocates call for cut-off lighting (lighting with no direct up-light) and energy-efficient bulbs to cut down on waste.