EDITOR’S COMMENTS

The appearance of the seventy-fifth edition of an annual publication is a notable event. Except for two years (1909 and 1910), The Royal Astronomical Society of Canada has produced an astronomical handbook for every year since 1907. In her foreword, Helen Hogg refers to some features of the first edition. John Percy, past-editor of the observer’s handbook, is preparing an article on the history of the handbook for the December 1982 issue of the Society’s Journal.

On behalf of The Royal Astronomical Society of Canada, I wish to thank the several contributors to the 1983 observer’s handbook (see the inside front cover). In particular, I wish to welcome Yoshio Kubo (lunar occultations) and Barry Madore (galaxies) as new contributors. They replace Leslie Morrison (Royal Greenwich Observatory) and Sidney van den Bergh (Dominion Astrophysical Observatory), respectively, both of whom have provided valuable service over several years.

Some revisions and additions have been made for 1983. The precession table, a feature of the handbook for many years, has been reinstated in recognition of its convenience. Precession formulae have been retained for those who prefer compu­ tation. Victor Gaizauskas has expanded his section to include the aurora. A sim­plified, graphical method has been devised for the determination of longitude corrections to moonrise/set times. On David Dunham’s suggestion, the number and location of U.S. standard stations for lunar occultations have been revised. The magnitude limit for total lunar occultation predictions has been changed from 7.5 to 6.0. A diagram of the main ring features of Saturn has been prepared (data courtesy of the Jet Propulsion Laboratory of the California Institute of Technology). The spacecraft Voyager 1 and Voyager 2 have revealed many satellites as worlds in their own right; a pronunciation guide to their names is now included. To facilitate observations of occultations by minor planets, updated predictions may now be obtained by telephone in both Canada and the United States. Peter Millman has expanded the section on meteors. A new section, Interplanetary Dust, has been prepared, including reference to the zodiacal light and the gegenschein. At Donald MacRae’s request, Robert Garrison (David Dunlap Observatory) has provided revised spectral types for forty stars in the table: The Brightest Stars. Janet Mattei has provided directions for the beginning observer of variable stars. Barry Madore has completely revised the section on galaxies.

In addition to the regular contributors, several other individuals have provided ideas, information, assistance, and/or constructive criticism. In particular I wish to thank Randall Brooks (Halifax, N.S.), Leo Enright (Sharbot Lake, Ont.), David Levy (Tucson, Ariz.), Warren Morrison (Peterborough, Ont.), Kenneth Rose (Bryn Athyn, Pa.), and B. Franklyn Shinn (Nanaimo, B.C.).

As always, the R.A.S.C. is indebted to the Nautical Almanac Office (U.S. Naval Observatory) and its Director, P. K. Seidelmann, for pre-publication material from The Astronomical Almanac. Without this support it would not be possible to publish the observer’s handbook on time. Also, I wish to acknowledge the invaluable support of Rosemary Freeman, Executive-Secretary of the R.A.S.C. Through its Department of Physics, Acadia University (Wolfville, Nova Scotia) provides sub­ stantial direct and indirect support toward the preparation of the handbook. Comments and suggestions should be directed to the Editor (address on inside front cover). Good observing quo ducit Urania!

Roy L. Bishop, Editor