As humankind enters the twenty-first century, ours is the first generation where the majority of children cannot routinely see the night sky in all its splendor and glory. The problem is caused by light pollution, excess or misdirected artificial light that alters the natural night sky. In the night sky, light pollution causes an atmospheric phenomenon known as skyglow. You may have seen overhead clouds at night glowing with strange pink or orange colors; this is wasted light reflecting off the water particles that form clouds. Even without clouds, light shoots into the sky and reflects off of tiny airborne dust and moisture particles. The skyglow phenomenon directly affects the scientific research of amateur and professional astronomers. It also affects everyone else who simply enjoys a dark night sky abundant with stars overhead. Scientists say that nearly two-thirds of the U.S. population can no longer...