The artist, James Gordon Irving, worked with skill and imagination. His wife, Grace Crowe Irving, assisted in research. David H. Heeschen of the Harvard Observatory and Ivan King of the University of Illinois Observatory helped with data and tables. Paul Lehr, of the National Oceanic and Atmospheric Administration, checked text involving meteorology. Hugh Rice of the Hayden Planetarium gave helpful advice, and our seasonal constellation charts owe much to his projections. Dorothy Bennett, for many years a member of the Hayden Planetarium’s staff, contributed greatly to our editorial planning. Isaac Asimov, Joe and Simone Gosner are to be credited for intermediate revisions; Mark R. Chartrand prepared the latest revision. Twelve new illustrations by Howard Friedman have been added for this edition.
Thanks are due the Lowell, Hale (Mt. Wilson and Mt. Palomar), Lick, Yerkes, and National Optical Astronomy observatories and NASA for the use of images.