Share Email Print

Spie Press Book

Rainbows, Halos, and Glories
Author(s): Robert Greenler
Format Member Price Non-Member Price

Book Description

Over two hundred illustrations, many in full color, capture for both the layman and scientist the beautiful optical effects that we see in the sky. The author describes and explains these effects in non-technical language. In addition to discussing such well-known phenomena as rainbows and halos, he treats the rarer ones, including sun pillars, sun dogs, glories, and mirages. Computer simulations and simplified mathematical models are used to make the physical origins of these events intelligible. The book sensitizes readers to a wide range of optical phenomena in the sky, explains how to look for them, and imparts an increased awareness and aesthetic appreciation of these fascinating effects. This new printing includes sharper color images and an expanded preface.

Book Details

Date Published: 15 September 2020
Pages: 238
ISBN: 9781510638372
Volume: PM321

Table of Contents
SHOW Table of Contents | HIDE Table of Contents

Table of Contents


1 Rainbows

2 Ice-crystal refraction effects: halos, arcs, and spots

3 Ice-crystal reflection effects: pillars, circles, and crosses

4 Complex displays, past and present

5 Scattering: light in the sky and color in the clouds

6 Diffraction: the corona, the glory, and the specter of the Brocken

7 Atmospheric refraction: mirages, twinkling stars, and the green flash

Appendix: Answers to puzzles


General references


2020 Preface Addendum

This volume was originally published 40 years ago, and it has been out of print for several years. I still get an occasional letter from someone who has just "discovered" the book and is enthusiastic about its contents. More often, I hear from people who are excited to have seen some beautiful effect in the sky and are delighted to understand its origin by looking at this book, which sits on their shelf.

We have decided to publish this edition without changes. Of course, since the original publication date, there has been increased understanding of some of the effects, and many more excellent color photos are now available. Nevertheless, I hope that the historical introduction and intuitive explanation of these effects will continue to excite and inform new readers of the beauty available to anyone who looks skyward with an inquiring eye.

A note concerning the ancient history of computer technology that is illustrated in this volume: When we first started doing the computer simulations - displayed as dot diagrams in this book - we created a deck of punched IBM cards, which constituted the computer program. This deck of cards was sent off by a daily van service from Milwaukee to Madison, where the main computer was located. An all-too-frequent next step was to have the stack of cards returned with a note that there was an error on card #372. Try again. After a successful run, the results were printed out on the 36-inch-wide sheet of paper of the wet-ink chart recorder we had in Milwaukee. Any of the more complicated displays might take an hour or more to plot, and there was a queue for people signed up to use the plotter. With this system, we would see the results of an idea for explaining the circumzenithal arc, for example, a minimum of 3 or 4 days after writing the program. As we persisted, the computing methods improved, but each of the simulations done in this book was made by photographing the large plots made on the wet-ink chart recorder. Even I, who was there, am amazed that we were able to produce these results with such "stone-age" technology.

I repeat my exhortation to the reader to develop the habit of looking at the world with fresh eyes—to search for the story behind the first visual impression—to see with the mind as well as the eye.

Robert Greenler

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?