the observer’s handbook for 1980 is the seventy-second edition. I thank all those who have contributed to its production: those listed on the inside front cover, and also my editorial assistants Tim Pointing and Douglas Welch.

I also thank all those who have sent me corrections to and suggestions about the handbook. Errors inevitably creep in; if you see one please let me know, obvious though it may be.

the observer’s handbook for 1979 is the seventy-first edition—at 140 pages, the largest edition ever. I thank all those whose names appear explicitly in the various sections, and especially the editor’s assistant, Jaymie M. Matthews.

the observer’s handbook for 1972 is the sixty-fourth edition. In response to sug­gestions from readers, several changes and improvements have been made and a number of errors and omissions in the 1971 edition have been rectified.

the observer’s handbook for 1978 is the seventieth edition. It has now grown to 128 pages: the predictions of total and grazing lunar occultations have been con­ siderably expanded to cover the whole of Canada and the U.S., and about a dozen other sections have been extensively revised and/or expanded.

the observer’s handbook for 1977 is the sixty-ninth edition. There are some changes and additions: the presentation of the configurations of Jupiter’s satellites, and of the sun’s selenographic colongitude, is different (see pg. 34); a diagram showing twilight and sidereal time has been added (pg. 12); the section on “Planets” has been rewritten and extended; and some “Suggestions for Further Reading” have been added. The index is now on the last page.

the observer’s handbook for 1976 is the sixty-eighth edition. I wish to thank all those who assisted in its preparation: those whose names appear in the various sections, those mentioned below, and especially my editorial assistant, John F. A. Perkins.

the observer’s handbook for 1975 is the sixty-seventh edition. I wish to thank all those who assisted in its preparation: those whose names appear in the various sec­ tions, those mentioned below, and especially my editorial assistant John F. A. Perkins.

the observer’s handbook for 1974 is the sixty-sixth edition. I wish to thank all those who assisted in its preparation: those whose names appear in the various sections, and my assistant editor Marie Fidler Litchinsky. Special thanks go to Margaret W. Mayall, Director of the A.A.V.S.O., for the predictions of Algol and of the variable stars, to Leslie V. Morrison and Gordon E.