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Observer's Handbook 1983

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Observer's Handbook 1983 EDITOR: ROY L. BISHOP THE ROYAL ASTRONOMICAL SOCIETY OF CANADA CONTRIBUTORS AND ADVISORS A l a n H. B a t t e n , Dominion Astrophysical Observatory, Victoria, BC, Canada V8X 3X3 (The Nearest Stars). R o y L. B is h o p , Department of Physics, Acadia University, Wolfville, NS, Canada B0P 1X0 (Editor). Terence Dickinson, R.R. 3, Odessa, ON, Canada K0H 2H0, (The Planets). D a v id W. D u n h a m , International Occultation Timing Association, P.O. Box 7488, Silver Spring, MD 20907, U.S.A. (Planetary Appulses and Occultations). Alan Dyer, Queen Elizabeth Planetarium, 10004-104 Ave., Edmonton, AB, Canada T5J 0K1 (Messier Catalogue, Deep-Sky Objects). M arie Fidler, Royal Astronomical Society of Canada, 124 Merton St., Toronto, ON, Canada M4S 2Z2 (Observatories and Planetaria). Victor Gaizauskas, Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Solar Activity). J o h n A. G a l t , Dominion Radio Astrophysical Observatory, Penticton, BC, Canada V2A 6K3 (Radio Sources). Ian H alliday, Herzberg Institute of Astrophysics, National Research Council, Ottawa, ON, Canada K1A 0R6 (Miscellaneous Astronomical Data). H e l e n S. H o g g , David Dunlap Observatory, University of Toronto, Richmond Hill, ON, Canada L4C 4Y6 (Foreword). Yoshio Kubo, International Lunar Occultation Centre, Astronomical Division, Hydrographic Department, Tsukiji-5, Chuo-ku, Tokyo, 104 Japan (Total and Grazing Lunar Occultations). D o n a ld A. M a c R a e , David Dunlap Observatory, University of Toronto, Richmond Hill, ON, Canada L4C 4Y6 (The Brightest Stars). B a r r y F. M a d o r e , David Dunlap Observatory, University of Toronto, Richmond Hill, ON, Canada L4C 4Y6 (Galaxies). B r i a n G. M a r s d e n , Smithsonian Astrophysical Observatory, Cambridge, MA, U.S.A. 02138 (Comets, Minor Planets). J a n e t A. M a t t e i , American Association of Variable Star Observers, 187 Concord Ave., Cambridge, MA, U.S.A. 02138 (Variable Stars). 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 , Departement de Physique, Universite de Montreal, Montreal, PQ, Canada H3C 3J7 (Star Clusters). John R. Percy, Erindale College and Department of Astronomy, University of Toronto, Toronto, ON, Canada M5S 1A7 (Sky Month by Month). Rene Racine, Director, Canada-France-Hawaii Telescope, P.O. Box 1597, Kamuela, Hawaii, U.S.A. 96743 (Galactic Nebulae). P. Blyth Robertson, Earth Physics Branch, Energy, Mines and Resources Canada, Ottawa, ON, Canada K1A 0Y3 (Meteorite Impact Sites). G o r d o n E. T a y l o r , H.M. Nautical Almanac Office, Royal Greenwich Observa­ tory, Hailsham, Sussex, England BN27 1RP (Planetary Appulses and Occulta­ tions). Jo s e p h F. V e v e r k a , Department of Astronomy, Cornell University, 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). PRINTED IN CANADA BY THE UNIVERSITY OF TORONTO PRESS OBSERVER’S HANDBOOK 1983 EDITOR ROY L. BISHOP SEVENTY-FIFTH YEAR OF PUBLICATION © THE ROYAL ASTRONOMICAL SOCIETY OF CANADA 124 MERTON STREET, TORONTO, ONTARIO M4S 2Z2 ISSN 0080-4193 THE FIRST OBSERVER’S HANDBOOK OF THE ROYAL ASTRONOMICAL SOCIETY OF CANADA, 1907 The first issue of this HANDBOOK appeared under the title “The CANADIAN ASTRONOMICAL HANDBOOK for 1907”. In 1911 the name became “THE OBSERVER’S HANDBOOK”. The first HANDBOOK was small, consisting of 108 pages 5 by 6½ inches in size. (By comparison the 1983 HANDBOOK has 176 pages, 5½ by 8½ inches.) In the “PREFACE” the distinguished Canadian astronomer, Dr. C. A. Chant, editor of both the HANDBOOK and the Journal of the Royal Astronomical Society of Canada, stated the purpose of the HANDBOOK as follows: “For a number of years, in several foreign countries astronomical annals, designed chiefly for the use of amateur observers, have been regularly published, and have been very effective in extending the interest in Astronomy. The present HAND­ BOOK aims to do a similar service for Canada. “Our country is still young and, as we might expect, the advance of Astronomy has not been so marked as in some other branches of knowledge; and yet in every part of the land are to be found those who have a profound interest in the celestial bodies above and in the natural phenomena about them. “The Royal Astronomical Society of Canada aims to unite in a common bond of interest all such students of nature. The object of the present work is to furnish, in a form understood by all, concise information regarding the chief astronomical phenomena to be observed in 1907; and it is hoped that the work will find its way into the hands of many who will add their names to the Society’s roll of membership. Anyone interested in Astronomy, Astronomical Physics or allied subjects is eligible for membership. “In preparing the work the Editor has received valued assistance from several members of the Society”. Chant then names the contributors. A few sections in this first HANDBOOK have vanished with the years. There is no longer need to give geographical positions of certain points in Canada such as the Astronomical Station in Calgary which was “1 chain 56 links south of centre line of C.P.R. main line, and 2 chains 49 links north of north-east comer of lot No. 11, in block 69”. Most of the sections in the 1907 HANDBOOK are still appearing in the 1983 edition, though in some cases with altered form or different title. The large section “MONTHLY PREDICTIONS FOR 1907” is now “THE SKY MONTH BY MONTH”. In 1907 this section included a transit of Mercury on November 14, partly visible in Canada. Two relatively long articles appear, “OBSERVING THE SUN, MOON AND PLANETS” by Andrew Elvins of Toronto, and “THE STUDY OF VARIABLE STARS” by J. Miller Barr of St. Catherines, Ontario. “RADIANTS OF THE CHIEF METEORIC SHOWERS” are tabulated by W. F. Denning of Bristol, England. Some general Society business is included, “EXTRACTS FROM THE BY-LAWS”, and “OFFICERS FOR 1907”. From these early beginnings, with its interest then chiefly in Canada, the Handbook has now evolved to a state useful over much of the North American continent, with important material from eight contributors outside Canada. With a broad and firm base like this, we foresee a long series of OBSERVER’S HANDBOOKS of the Royal Astronomical Society of Canada. H e l e n S a w y e r H o g g 2 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 h a n d b o o k 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 o b s e r v e r ’s h a n d b o o k (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 h a n d b o o k 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 sim­ plified, 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.
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