Parents don't know what to say when their children ask.
Why the Sky Is Blue answers this ancient and surprisingly complex question in a more entertaining and accessible way than ever before. Götz Hoeppe takes the reader on a historical and scientific journey to show the various ways people in different times and places have explained why the sky looks blue. The richly illustrated story begins with ancient myths and philosophy and ends with the cutting-edge science of optics, statistical physics, and ozone depletion. Most importantly, it is the story of how scientists discovered that the sky's blue depends on life on Earth and the makeup of our planet's ozone layer. Without microbial life's impact on the composition of the atmosphere, the clear daytime sky would probably lack its distinctive color. And without the ozone, the twilight sky's color would also be very different—not the sapphire tone of l'heure bleue, but rather a yellowish or greenish hue.
Why the Sky Is Blue shows that skylight can be viewed from a surprising variety of vantage points. We learn how our physiology and cognitive capacities govern our perception of the sky's color. And we discover why this everyday experience has been such a source of fascination and controversy over the centuries.
Delightful and intriguing, Why the Sky Is Blue shows how the attempt to answer this age-old and deceptively simple question only enhances the magic of the blue sky we see above us.
Götz Hoeppe is an editor of the popular German science magazine Spektrum der Wissenschaft and a lecturer in social anthropology at Heidelberg University. He is the author of Conversations on the Beach: Fishermen's Knowledge, Metaphor and Environmental Change in South India.
Table of Contents
List of Illustrations ix List of Tables xvii Acknowledgments xix Prologue: Looking at the Sky 1 Chapter 1: Of Philosophers and the Color Blue 9 Chapter 2: A Blue Mixture: Light and Darkness 31 Chapter 3: Aerial Perspective 52 Chapter 4: A Color of the First Order 77 Chapter 5: Basic Phenomenon, or Optical Illusion? 108 Chapter 6: A Polarized Sky 131 Chapter 7: Lord Rayleigh's Scattering 169 Chapter 8: Molecular Reality 203 Chapter 9: Ozone's Blue Hour 235 Chapter 10: The Color of Life 261 Epilogue 289 Appendix A: Determining the Height of the Atmosphere from the Duration of Twilight 291 Appendix B: Blue Eyes as Turbid Media 293 Appendix C: A Simple Derivation of the Inverse Fourth Power Law 295 Appendix D: Atmospheric Extinction and Avogadro's Number 297 Notes 299 Further Reading 311 Index 325
Praise for the original German edition: "In this richly illustrated volume, the author describes and explains the color and appearance of the firmament, from earlier times to the current day. It is an exciting excursion from mythology, art, and philosophy up through modern science.
Eileen Reeves
An absorbing study of historical approaches to the everyday fact of the blue sky above us, Götz Hoeppe's Why the Sky is Blue is full of revelations. The story it tells of the sky's appearance as an issue of speculation and investigation will appeal both to the specialist and the general reader. — Eileen Reeves, author of "Painting the Heavens: Art and Science in the Age of Galileo"
Saarlandischer Rundfunk
Praise for the original German edition: "Hoeppe has succeeded in something completely special: the book combines the research of the natural sciences with philosophical and cultural reflections-all elegantly expressed.
James Rodger Fleming
This delightful combination of science and history should be required reading for poets, pilots, artists, weather watchers, and anyone who ever marveled at the manifest colors of the sky or wondered why it is only sometimes 'blue.' — James Rodger Fleming, Colby College
From the Publisher
"This delightful combination of science and history should be required reading for poets, pilots, artists, weather watchers, and anyone who ever marveled at the manifest colors of the sky or wondered why it is only sometimes 'blue.'"—James Rodger Fleming, Colby College"An absorbing study of historical approaches to the everyday fact of the blue sky above us, Götz Hoeppe's Why the Sky is Blue is full of revelations. The story it tells of the sky's appearance as an issue of speculation and investigation will appeal both to the specialist and the general reader."—Eileen Reeves, author of Painting the Heavens: Art and Science in the Age of GalileoPraise for the original German edition: "In this richly illustrated volume, the author describes and explains the color and appearance of the firmament, from earlier times to the current day. It is an exciting excursion from mythology, art, and philosophy up through modern science."—Die WeltPraise for the original German edition: "This is a multilayered book that makes a seemingly commonplace observation the starting point of an exciting journey of discovery . . . The color of the sky proves to be the key to understanding many of our cultural achievements in science, art and everyday life."—NDR 1's BücherweltPraise for the original German edition: Hoeppe has succeeded in something completely special: the book combines the research of the natural sciences with philosophical and cultural reflections-all elegantly expressed."—Saarländischer Rundfunk
