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THE OBSERVER’S HANDBOOK 1969 Sixty-first Year of Publication THE ROYAL ASTRONOMICAL SOCIETY OF CANADA THE ROYAL ASTRONOMICAL SOCIETY OF CANADA Incorporated 1890 — Royal Charter 1903 The National Office of the Royal Astronomical Society of Canada is located a t 252 College Street, Toronto 2B, Ontario. The business office of the Society, reading rooms and astronomical library, are housed here. Membership in the Society is open to anyone interested in astronomy. Applicants may affiliate with one of the Society’s sixteen centres across Canada, or may join the National Society direct. Centres of the Society are established in St. John’s, Quebec, Montreal, Ottawa, Kingston, Hamilton, Niagara Falls, London, Windsor, Winnipeg, Edmonton, Calgary, Vancouver, Victoria, and Toronto. Addresses of the Centres’ secretaries may be obtained from the National Office. Publications of the Society are free to members, and include the J ournal (6 issues per year) and the Observer’s H andbook (published annually in November). Annual fees of $7.50 are payable October 1 and include the publi­ cations for the following year. VISITING HOURS AT SOME CANADIAN OBSERVATORIES David Dunlap Observatory, Richmond Hill, Ont. Tuesday mornings, 10:00-11:00 a.m. Saturday evenings, April through October (by reservation). Dominion Astrophysical Observatory, Victoria, B.C. Monday to Friday, daytime, no program. Saturday evenings, April through November. Dominion Observatory, Ottawa, Ont. Monday to Friday, daytime, rotunda only. Saturday evenings, April through October. Dominion Radio Astrophysical Observatory, Penticton, B.C. Sunday, July and August only (2:00-5:30 p.m.). Planetariums: Calgary Centennial Planetarium, Calgary, Alta. Daily (except Tues.), 2, 3:15, 7, 8:15 p.m. Dow Planetarium, Montreal, P.Q. In English: Mon. through Sat., 3:30 p.m., also Sat. 1 p.m. and Sun. 2:15 p.m. Evenings (except Mon.), 8:15. In French: Mon. through Sat., 2:15 p.m., Sun., 1 and 3:30 p.m. Evenings (except Mon.), 9:30. H.R. MacMillan Planetarium, Vancouver, B.C. Tues. through Thur., 3, 8 p.m., Fri. 3, 7:30, 9 p.m., Sat. 1:30, 3, 8 p.m., Sun. and holidays, 1:30, 3, 4:30, 8 p.m. (During summer months, Tues. through Sun. at 1:30, 3, 7:30, 9 p.m.) Manitoba Museum of Man and Nature Planetarium, Winnipeg, Man. Tues. through Fri., 3, 7:30, 9 p.m., Sat. 11 a.m., 1, 2:30, 4 and 8 p.m., Sun. 1, 2:30 and 4 p.m. McLaughlin Planetarium, Toronto, Ont. Tues. through Fri., 3:30, 8 p.m., Sat. 11 a.m., 2, 3:30, 5 and 8 p.m., Sun. 2, 3:30 and 5 p.m. McMaster University, Hamilton, Ont. (group reservations only). Nova Scotia Museum, Halifax, N.S. (Tues. only, 8 p.m.). Queen Elizabeth Planetarium, Edmonton, Alta. (Winter) Tues. through Fri., 8 p.m., Sat. 3 p.m., Sun. and holidays, 2, 4, 8 p.m. (Summer) Mon. through Sat., 3, 8 p.m., Sun. and holidays, 2, 3, 4, 8 p.m. University of Manitoba, Winnipeg, Man. Tues. 8:30 p.m., Thurs. 7:30, 9 p.m. (closed April and May). THE OBSERVER’S HANDBOOK 1969 E ditor R u th J. N orthcott Sixty-first Year of Publication THE ROYAL ASTRONOMICAL SOCIETY OF CANADA 252 C ollege S t r e e t , T oronto 2 B , O ntario PAGE Anniversaries and F estiv als ......................................................................................3 Asteroids—Ephemerides at O pposition ..................................................................70 C lu s te r s ........................................................................................................................90 Constellations.............................................................................................................. 5 E c lip s e s ........................................................................................................................ 64 Galaxies .......................................................................................... 93 Julian C alendar .................................................................................................. 3 Jupiter—Bands and Z o n e s ..........................................................................................57 —Longitude of Central M eridian.............................. 60 —Phenomena of Satellites..............................................................................56 Mars—Longitude of Central M e r i d i a n ..................................................................61 Messier’s Catalogue.......................................................................................................96 Meteors, Fireballs and Meteorites............................................................ 71 Miscellaneous Astronomical D ata ................................................................................6 Moon—Observation......................................................................................................61 Moonrise and M oonset................................................................................................20 Nebulae—G alactic ......................................................................................................92 Occultations—by M o o n ..........................................................................................64 —by Planets; Appulses........................................................................70 Planets—G eneral ......................................................................................................26 —E le m en ts........................................................................................................8 Precession for 50 Y ears................................................................................................72 Radio Sources ............................................................................................................95 Satellites of Solar System (L is t) ................................................................................9 Saturn—R ings ............................................................................................................ 59 —Satellites ......................................................................................................59 Sky and Astronomical Phenomena Month by M o n th ..........................................32 Solar System—E lem ents ............................................................................................8 —Satellites ( L is t) ................................................................................ 9 Star M a p s .................................................................................................................. 97 Stars—Brightest (Positions, etc .) ..............................................................................74 —Double and M ultiple .................................................................................... 85 —Names, Finding L i s t ....................................................................................73 —N e a re s t.................................... 86 —V ariable............................................................................................................ 88 Sun—Ephemeris.............................................................................................................. 7 —Physical Observations....................................................................................63 —Sun-spot C y c le ................................................................................................26 Sunrise and Sunset...................................................................................................... 13 Symbols and A bbreviations......................................................................................4 Time—Correction to Sun-dial......................................................................................7 —Radio Time Signals..........................................................................................11 —Solar, Sidereal, Universal, Standard, E p h e m e r i s ................................... 10 —Zones ( M a p ) .............................................................................................. 11a Twilight ............................................................................................................ 19 PRINTED IN CANADA BY THE UNIVERSITY OF TORONTO PRESS THE OBSERVER’S HANDBOOK for 1969 is the 61st edition. The time zone map has been revised and supplied courtesy of the Department of Energy, Mines and Resources. A table giving the longitude of the central meridian of Mars has been added. Changes have been made in the table of Saturn’s satellites, so that it will be more useful to observers. The times of sunrise and sunset, and of twilight, are again for the current year. The magnitudes in the table of Messier’s objects have been revised. During 1969 the range of the moon’s declination reaches its greatest ue, so that the moon occults stars of the Pleiades. Observers in Montreal, Winnipeg and Vancouver may find that the stars occulted by the moon may not be in strict chronological order (see p. 64). Cordial thanks are offered to all individuals who assisted in the preparation of this edition, to those whose names appear in the various sections and to Barbara Gaizauskas, Helen Sawyer Hogg, Ronald Nikaido, John Percy, Maude Town and Isabel Williamson. Special thanks are extended to Margaret W. Mayall, Director of the A.A.V.S.O., for the predictions of Algol and the variable stars, and to Gordon E. Taylor and the British Astronomical Association for the prediction of planetary appulses and occultations. My deep indebtedness to the
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