Most life on Earth is synchronized to the regular cycles of day and night. Until about a hundred years ago, the natural night sky was familiar to all humans. Most people could identify a few constellations and had experienced walking by starlight. Now all but a few are denied the privilege of seeing the Milky Way or a meteor streaking across the sky. To gaze into a star filled sky and wonder about other life which may exist in the Universe is worth preserving for future generations.