Something about the Moon calls to us. Looming red and swollen as it rises, or shining with a silver glow high overhead, the Moon draws our attention like no other celestial object. As our nearest cosmic neighbor, it has been an object of worship, a source of myths, the subject of countless films, books and works of art and the focus of our first venture into outer space. It is a source of wonder for us in its many guises and phases, sizes and colors.