OBSERVER’S HANDBOOK 1 9 8 9 EDITOR: ROY L. BISHOP THE ROYAL ASTRONOMICAL SOCIETY OF CANADA CONTRIBUTORS AND ADVISORS Alan H. B atten, Dominion Astrophysical Observatory, 5071 W . Saanich Road, Victoria, BC, Canada V8X 4M6 (The Nearest Stars). L a r r y D. B o g a n , Department of Physics, Acadia University, Wolfville, NS, Canada B0P 1X0 (Configurations of Saturn’s Satellites). Terence Dickinson, Yarker, ON, Canada K0K 3N0 (The Planets). D a v id W. D u n h a m , International Occultation Timing Association, 7006 Megan Lane, Greenbelt, MD 20770, U.S.A. (Lunar and Planetary Occultations). A lan Dyer, A lister Ling, Edmonton Space Sciences Centre, 11211-142 St., Edmonton, AB, Canada T5M 4A1 (Messier Catalogue, Deep-Sky Objects). Fred Espenak, Planetary Systems Branch, NASA-Goddard Space Flight Centre, Greenbelt, MD, U.S.A. 20771 (Eclipses and Transits). M a r ie F i d l e r , 23 Lyndale Dr., Willowdale, ON, Canada M2N 2X9 (Observatories and Planetaria). Victor Gaizauskas, J. W. D e a n , Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Solar Activity). R o b e r t F. G a r r i s o n , David Dunlap Observatory, University of Toronto, Box 360, Richmond Hill, ON, Canada L4C 4Y6 (The Brightest Stars). Ian H alliday, Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Miscellaneous Astronomical Data). W illiam H erbst, Van Vleck Observatory, Wesleyan University, Middletown, CT, U.S.A. 06457 (Galactic Nebulae). Ja m e s T. H im e r, 339 Woodside Bay S.W., Calgary, AB, Canada, T2W 3K9 (Galaxies). H e l e n S. H o g g , David Dunlap Observatory, University of Toronto, Box 360, Richmond Hill, ON, Canada L4C 4Y6 (Foreword). D a v id H. L e v y , Jamac Observatory, Route 7, Box 414, Tucson, AZ, U.S.A., 85747 (Comets). B a r r y F. M a d o r e , David Dunlap Observatory, University of Toronto, Box 360, Richmond Hill, ON, Canada L4C 4Y6 (Galaxies). B r i a n G. M a r s d e n , Smithsonian Astrophysical Observatory, 60 Garden St., Cambridge, MA, U.S.A. 02138 (Comets, Asteroids). J a n e t A. M a t t e i , American Association of Variable Star Observers, 25 Birch St., Cambridge, MA, U.S.A. 02138-1205 (Variable Stars). R o b e r t L. M i l l i s , Lowell Observatory, Mars Hill Road, 1400 West, Flagstaff, AZ, U.S.A. 86001 (Planetary Appulses and Occultations). P e t e r M. M i l l m a n , Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Meteors, Fireballs and Meteorites). A n t h o n y F. J. M o f f a t , Département de Physique, Université de Montréal, Montréal, PQ, Canada H3C 3J7 (Star Clusters). J o h n R. P e r c y , Erindale College and Department of Astronomy, University of Toronto, Toronto, ON, Canada M5S 1A1 (Sky Month by Month). P. B lyth Robertson, Energy, Mines and Resources Canada, 1 Observatory Crescent, Ottawa, ON, Canada K1A 0Y3 (Meteorite Impact Sites). Akio Senda, International Lunar Occultation Centre, Geodesy and Geophysics Division, Hydrographic Department, Tsukiji-5, Chuo-ku, Tokyo, 104 Japan (Total and Grazing Lunar Occultations). Ken Tapping, Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Radio Sources). J o s e p h F. V e v e r k a , Centre for Radiophysics and Space Research, Cornell Uni­ versity, Ithaca, NY, U.S.A. 14853 (Planetary Satellites). C h a r l e s E. W o r l e y , U.S. Naval Observatory, Washington, DC, U.S.A. 20390 (Double Stars). OBSERVER’S HANDBOOK 1989 EDITOR ROY L. BISHOP EIGHTY-FIRST YEAR OF PUBLICATION © THE ROYAL ASTRONOMICAL SOCIETY OF CANADA 136 DUPONT STREET, TORONTO, ONTARIO M5R 1V2 1988 ISSN 0080-4193 PRINTED IN CANADA BY THE UNIVERSITY OF TORONTO PRESS IN PRAISE OF AMATEUR ASTRONOMERS B y H e l e n S a w y e r H o g g And especially Canadian amateurs, in order to confine my words to the available space. Actually I could use almost all this space just discussing what is meant by the term “amateur astronomer” and various reactions to it. We could start with the definition of “amateur” from Webster's Third New International Dictionary, unabridged: “one that engages in a particular pursuit, study or science as a pastime rather than as a profession”. And the definition of “profession” is: “a principal calling, vocation or employment.” But precise meanings of words are often elusive. I was startled recently to hear one of our distinguished historians of science declare that Galileo was NOT an astronomer. Who deserves the title more than someone who discovered the craters on the Moon and the moons of Jupiter? In recent years, since I retired from the University payroll, I have wondered if, despite almost 50 years working as a professional astronomer, I am now best described as an amateur astronomer. The term amateur astronomer certainly covers a wide range of activities. At the top of this category are those observers really dedicated to a study of the sky. They manage to spend many night hours, often well bundled up against harsh elements, scanning the skies with a particular field of interest in mind. Unlike many of us, they seem able to get along on very few hours sleep, and maintain their regular job by day. In recent years the discoveries of Canadian amateurs have been really notable. The person who gives us the up-to-date information about them is Terence Dickinson. For almost 50 years the Toronto Star has had a weekly column on Saturdays on astronomy. Dickinson took over writing this when I gave up the task in 1981 after 30 years. His columns are full of the latest discoveries of both amateur and professional astronomers. The title of the column has expanded considerably from “With The Stars” to “The Universe”. Dickinson’s articles also appear in the beautiful periodical Equinox and other publications, and he has written some fine books. Dickinson estimates that there are 30 000 amateur astronomers in Canada. Most of those making prominent discoveries are R.A.S.C. members. We can mention only a few. Warren Morrison of Peterborough, Ontario discovered Nova Cygni in 1978 and in January, 1985 caught the recurrent nova RS Ophiuchi on its first observed upswing in 18 years. Rolf Meier of Ottawa is the top Canadian observer for comets because he has discovered four from an observatory in Canada. His rival is Canadian David Levy who has also found four, but Levy works near Tucson, Arizona for better observing conditions. Recently Asteroid 3673 was named for Levy in recognition of his work. Jack Newton of Victoria, B.C. has taken and published many outstanding photographs, using telescopes and cameras of his own design, and now has a second book in press with Philip Teece (Cambridge University Press). Clifford Cunning­ ham of Kitchener has had years of devotion to asteroids which have culminated this past year with invitations to use large professional telescopes and the publication of his attractive book, with human appeal, Introduction to Asteroids. Andrew Lowe of Calgary is one of the few observers who has had the good fortune to watch an asteroid blot out a star. An unusual branch of amateur astronomy is pursued by Real Manseau of Drummondville, Quebec, who makes detailed replicas of historical astronomical instruments such as Isaac Newton’s first reflecting telescope. Few amateurs are engaged in radio astronomy, but Frank Roy of Ottawa is, and hopes to make an all-sky radio survey. 3 A large proportion of amateurs are simply “armchair astronomers”. They delight in reading astronomical items, they talk astronomy at social gatherings, and their monetary donations help maintain societies like this one. We are indebted to them for the fostering of public interest in astronomy. Then there are the “casual observers” whose interest in the sky has been sparked by a contemporary celestial event or even a chance remark. With binoculars or telescopes, especially on mild summer nights, they enjoy finding the beauties of the heavens, the moons of Jupiter, the rings of Saturn, the double cluster in Perseus, and the most distant object the human unaided eye can see, the Great Galaxy in Andromeda. Then there are the “telescope makers” who delight in building their own, often complex instruments. Some in this category become more interested in the instrument than in studying the sky itself. All sorts of astronomical undertakings except those requiring the most expensive and sophisti­ cated instrumentation have amateurs in their midst. Over the decades and the centuries, amateur astronomers of many nations have made a massive and a significant contribution to our understanding of the universe. Now the dictionary gives another definition of amateur: “one that engages in an activity in an inexperienced or incompetent manner”. This definition certainly does NOT apply to readers and users of the Observer's Handbook who are pursuing a most excellent course for astronomical experience and competence. COVER PHOTOGRAPH Unlike many photographs involving the Moon and other objects, this image of seven Canada Geese against the Harvest Moon is not a superposition of two separate photographs. This singular image was taken on October 2, 1982 (23:00 EDT) by Hein van Asperen of Brockville, Ontario, a member of the Kingston Centre of The Royal Astronomical Society of Canada.