Optics in the air : observing optical phenomena through airplane windows Preface Glossary 1. Introduction 2. Sky colors 3. Coronas and iridescence 4. Rainbows and cloud bows 5. Glories 6. Shadows 7. Water colors and glitter 8. Halos and pillars 9. Noctilucent clouds and aurora 10. Colors from polarization 11. Scenery and interesting sights Appendix: International airport codes Most naturally occurring optical displays can be seen from an airplane and some are best viewed while airborne. This book is an introduction to optical phenomena in the natural world primarily in the atmosphere (or in the air ). It follows a simple approach that can be understood and enjoyed by readers without scientific training. A variety of optical phenomena are illustrated with photographs and explained with simplified line diagrams and descriptions. These phenomena range from everyday sky and sunset colors to the elusive noctilucent clouds and aurora as well as a whole world of too often ignored occurences such as sun glitter patterns on bodies of water colorful ringed glories and coronas rainbows that cling to the clouds below a high flying airplane and ice halos that spring up as an airplane passes through high altitude ice clouds