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April 2020 Journal The Journal of The Royal Astronomical Society of Canada PROMOTING ASTRONOMY IN CANADA April/avril 2020 Volume/volume 114 Le Journal de la Société royale d’astronomie du Canada Number/numéro 2 [801] Inside this issue: Cepheid Variables in Andromeda Supernova Redshifts 2019 Awards Corona Australis The Best of Monochrome. Drawings, images in black and white, or narrow-band photography. The magnificent California Nebula was imaged by Ron Brecher’s home observatory in Guelph, Ontario. It is a 16-hour exposure through a 106mm ƒ/3.6 refractor, combining 12hr20m collected with a one-shot colour camera and 4hr30m collected with a monochrome camera. April / avril 2020 | Vol. 114, No. 2 | Whole Number 801 contents / table des matières Research Articles / Articles de recherche 92 Dish on the Cosmos: King of The Radio Sky by Erik Rosolowsky 56 Cepheid Variables in the Andromeda Galaxy from Simon Fraser University’s Trottier 94 Celestial Review: Algol at Minimum Observatory by Dave Garner by Howard Trottier et al. 96 Imager’s Corner: CGX-L Review 67 Matching Supernova Redshifts with Special by Blair MacDonald Relativity and no Dark Energy by Simon Brissenden 100 Observing: Springtime Observing with Coma Berenices by Chris Beckett Feature Articles / Articles de fond 80 Pen and Pixel: Orion / Comet PANSTARRS Departments / Départements C/2017 T2 / Dumbbell Nebula / Cone Nebula. 50 President’s Corner Blake Nancarrow / Klaus Brasch / Tom Owen / Gary Palmer by Dr. Chris Gainor Columns / Rubriques 51 News Notes / En manchettes Compiled by Jay Anderson 71 Skyward: First Light and Something Old, Something New 101 Awards for 2019 by David Levy Compiled by James Edgar 73 CFHT Chronicles: Behind the Data at CFHT 112 Astrocryptic and February Answers by Mary Beth Laychak by Curt Nason 77 Binary Universe: Take Control of Your Mount iii Great Images by Blake Nancarrow by Luca Vanzella 89 John Percy’s Universe: Assassin: The Survey by John R. Percy “Space is a pretty dynamic place, and there is a lot going on in this area called Corona Australis Complex,” said Debra Ceravolo. Peter Ceravolo acquired the data from San Pedro de Atacama in Chile, using the Ceravolo 300 Astrograph at ƒ/4.9 on a Paramount ME. Debra processed the image using MaximDL and PixInsight. Total exposure was 7.2 hours: LRGB: 285, 50, 30 and 35 minutes. “Some dust (blue refl ection nebula) is getting lit up by nearby bright stars and the dark dust cloud is not. It is all about 500 light-years away except the globular cluster (NGC 6723) is 30,000 light-years away. Put that in perspective!” she says. April / avril 2020 JRASC | Promoting Astronomy in Canada 49 The Journal is a bi-monthly publication of The Royal President’s Corner Astronomical Society of Canada and is devoted to the advancement of astronomy and allied by Christopher Gainor, Ph.D., Victoria Centre sciences. It contains articles on Canadian astronomers and current activities of the RASC and its Centres, research and review papers by professional and amateur astronomers, ([email protected]) and articles of a historical, biographical, or educational nature of general interest to the astronomical community. All contributions are welcome, but the editors reserve the right to edit material prior to publication. Research papers are reviewed prior to publication, For most RASC members, getting together usually means and professional astronomers with institutional affi liations are asked to pay publication some activity within a Centre, such as a monthly meeting, charges of $100 per page. Such charges are waived for RASC members who do not have access to professional funds as well as for solicited articles. Manuscripts and other observing night, annual banquet, or even an informal activity submitted material may be in English or French, and should be sent to the Editor-in-Chief. like the weekly Astro Café that has become a popular event in my home Centre in Victoria. Editor-in-Chief Contributing Editors Nicole Mortillaro Jay Anderson (News Notes) Email: [email protected] Chris Beckett (Observing Tips) Getting the Society together at the National level is more Web site: www.rasc.ca Mary Beth Laychak (CFHT Chronicles) di cult because, as our former Prime Minister, William Lyon David Levy (Skyward) Telephone: 416-924-7973 Mackenzie King, once observed, in Canada we have too much Fax: 416-924-2911 Blair MacDonald (Imager’s Corner) Blake Nancarrow (Binary Universe) geography. Associate Editor, Research Curt Nason (Astrocryptic) Douglas Hube John R. Percy (John Percy’s Universe) Email: [email protected] Randall Rosenfeld (Art & Artifact) For much of its existence, the RASC’s only National event was Associate Editor, General Eric Rosolowsky (Dish on the Cosmos) its Annual General Meeting, which, until 1960, always took Leslie J. Sage (Second Light) Michael Attas place in Toronto. at event traditionally involved only dealing David Turner (Reviews) Email: [email protected] Proofreaders with Society business, but in 1959 the meeting was expanded Assistant Editors Michael Attas to include papers on astronomy. e following year the Michael Allen Margaret Brons Martin Beech enlarged event took place in Montréal, marking the beginning Angelika Hackett Dave Chapman Michelle Johns of our annual General Assemblies. Ralph Chou Barry Jowett Ralph Croning Kim Leitch e GAs that followed over the past six decades have usually Dave Garner Alida MacLeod Patrick Kelly taken place on university campuses in various parts of the Design/Production Production Manager Michael Gatto, Grant Tomchuk country, usually on either the Victoria Day or, more recently, James Edgar Email: [email protected], the Canada Day long weekends. National Council meetings, Email: [email protected] [email protected] Society banquets, the Annual General Meeting and paper Advertising Printing Adela Zyfi Cansel presentations have been staples of every GA. Email: [email protected] www.cansel.ca For many years Centres competed to host the GA, but in Her Excellency the Right Honourable Julie Payette, C.C., C.M.M., C.O.M., C.Q., C.D., recent years interest in hosting these meetings has declined Governor General of Canada, is the Viceregal Patron of the RASC. to the point where the 2019 GA was largely organized out of The Journal of The Royal Astronomical Society of Canada is published at an annual the National O ce. ere are several reasons for this change, subscription rate of $93.45 (including tax) by The Royal Astronomical Society of Canada. Membership, which includes the publications (for personal use), is open to anyone but a major one is that General Assemblies based at univer- interested in astronomy. Applications for subscriptions to the Journal or membership in the sities have become more complicated to organize and less RASC and information on how to acquire back issues of the Journal can be obtained from: convenient for many people to attend. The Royal Astronomical Society of Canada 203 – 4920 Dundas St W A few years ago I asked for input from interested members Toronto ON M9A 1B7, Canada and then wrote a report suggesting that we make some Email: nationaloffi [email protected] changes to the format of GAs. In 2019, we held the GA in Web site: www.rasc.ca Telephone: 416-924-7973 the middle of June instead of on a long weekend, a change Fax: 416-924-2911 that was seen as successful. Canadian Publications Mail Registration No. 09818 Canada Post: Send address changes to 203 – 4920 Dundas St W, Toronto ON M9A 1B7 Another idea was to move the GA away from universities. e 2020 General Assembly is taking place the weekend of Canada Post Publication Agreement No. 40069313 June 5 to 7 at the Executive Plaza and Conference Centre in We acknowledge the fi nancial support of the Government of Canada through the Coquitlam, B.C., which is conveniently located near a stop on Canada Periodical Fund (CPF) for our publishing activities. Greater Vancouver’s SkyTrain system. In a nod to our history, © 2020 The Royal Astronomical Society of Canada. one evening’s activities will take place at Simon Fraser Univer- All rights reserved. ISSN 0035-872X sity in Burnaby and include a visit to the Trottier observatory on campus. Cert no. SW-COC-005174 While hotel accommodations are more expensive than university residences, meetings in hotels are generally easier 50 JRASC | Promoting Astronomy in Canada April / avril 2020 to organize since that is their business and not a sideline. We such as Bob McDonald, host of CBC’s Quirks and Quarks, and also believe that GA organizers should focus more on activities top- ight astrophysicists including Michael Landry, Aaron that will draw local audiences and help build their Centres. We Boley, Jess McIver, and Jaymie Mathews. More speakers and hope that these changes encourage more Centres to consider many exciting activities can be found on the 2020 GA website hosting GAs and rebuild interest in this vital national activity. ga2020.rasc-vancouver.com. e Vancouver organizing committee for the 2020 GA is I look forward to seeing many friends from Greater Vancouver ✶ doing a great job putting the weekend together with speakers and around Canada at the 2020 General Assembly! News Notes / En manchette with northern lights enthusiasts and the answers she provided to questions about the physics of the phenomenon in the (Compiled by Jay Anderson) hobbyists’ Facebook group. Green dunes: A new form of aurora ousands of magni cent photographs of the northern lights taken by hobbyists were surveyed and categorized for the book. Working together with space researchers, Finnish amateur Each auroral form is like a ngerprint, typical only of a certain photographers have discovered a new auroral form. Named phenomenon in the auroral zone. During the classi cation, “dunes” by the hobbyists, the origins of the feature were hobbyists pointed out that a certain auroral form did not t tracked to a wave guide formed within the mesosphere and its into any of the pre-existing categories.
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