The Journal of The Royal Astronomical Society of Canada PROMOTING ASTRONOMY IN CANADA June/juin 2015 Volume/volume 109 Le Journal de la Société royale d’astronomie du Canada Number/numéro 3 [772] Inside this issue: Persistent Meteor Train March 20 Eclipse DDO and World War II Inviting the Right Aliens to Tea Study in Blue and Gold The Best of Monochrome. Drawings, images in black and white, or narrow-band photography. Galaxy clusters are difficult to recognize in normal colours, so Dalton Wilson inverted this image to make the individual members of the Hercules Cluster (Abell 2151) stand out. The cluster lies at a distance of 500 mly. Dalton used an Astro Tech 10″ RC AP67FR with a QSI540wsg camera for an exposure of 3×300s in RGB and a 2×2-binned 4×900s Luminance. He notes that over 40 galaxies were counted in the image; the cluster contains around 200 galaxies in total. June/juin 2015 | Vol. 109, No. 3 | Whole Number 772 contents / table des matières Research Papers / Articles de recherche Departments / Départements 101 Time-Sequence Study of a Persistent Meteor Train 94 President’s Corner by W. John McDonald and Reg Dunkley by James Edgar Feature Articles / Articles de fond 95 News Notes / En manchettes Compiled by Jay Anderson 108 The March 20 Total Solar Eclipse – Green filaments show past quasar activity by Jay Anderson – New Hubble Source Catalog 110 David Dunlap Observatory and World War II – ESA begins planning Asteroid Impact Mission by Lee Robbins – New Hubble image of Messier 22 – The Milky Way’s most distant globular cluster 113 Inviting the Right Aliens to Tea—the State of the – Fast-rotating asteroid litters Solar System with dust Question at the Victoria Centre, 1931 – Astronomers solve decades-long mystery of the by R.A. Rosenfeld “lonely old stars” Columns / Rubriques 140 Reviews / Critiques Heart of Darkness, Unraveling the Mysteries of the Invisible 118 Pen and Pixel: Pleiades / NGC 4565 / M78 / Aurora Universe Mike Bonin / Dan Meek / Lynn Hilborn / Steve Irvine 141 RASC Travel 122 CFHT Chronicles: Diary of a Sunwatcher by Mary Beth Laychak 142 Great Images 125 Second Light: Saturn’s Rotation Period 143 Notes From the National Secretary by Leslie J. Sage by Karen Finstad 126 Orbital Oddities: Inferiority Complex 143 Erratum by Bruce McCurdy 144 Astrocryptic and April Answers 130 Binary Universe: Sky Conditions at Your Finger Tip by Curt Nason by Blake Nancarrow 144 It’s Not All Sirius 132 John Percy’s Universe: BRITE-Constellation: Canada’s “Shoebox Satellites” for Variable-Star Research By Ted Dunphy by John R. Percy iii Great Images 134 Dish on the Cosmos: Gravitational Lensing by Erik Rosolowsky 136 Imager’s Corner: Star Fix by Blair MacDonald Front cover — Dan Meek provides Journal readers with this image of the core of IC 1805 (the Heart Nebula), an emission nebula lying at a distance of 7500 light-years in Cassiopeia. The nebula’s emission is stimulated by ultraviolet radiation arising from a small group of hot stars near the nebula’s centre. Dan caught the photons for this image last October with a 270-minute exposure using a Tele Vue NP127 telescope with a QSI583wsg camera. June / juin 2015 JRASC | Promoting Astronomy in Canada 93 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 sciences. by James Edgar, Regina Centre It contains articles on Canadian astronomers and current activities of the RASC and its Centres, research and review papers by professional and amateur astronomers, and articles ([email protected]) 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, and professional astronomers with institutional affiliations are asked to pay publication charges of $100 per April 6 was a momentous day, as Prime page. Such charges are waived for RASC members who do not have access to professional Minister Stephen Harper announced in funds as well as for solicited articles. Manuscripts and other submitted material may be Vancouver, B.C., the Canadian funding of the enclosure and in English or French, and should be sent to the Editor-in-Chief. Adaptive Optics system for the Thirty-Meter Telescope. Editor-in-Chief Contributing Editors Jay Anderson Jim Chung (Cosmic Contemplations) This has long been in the planning stages, and it looked last 203 – 4920 Dundas St W Ted Dunphy (It’s Not All Sirius) year like it wouldn’t happen, as the money wasn’t in the 2014 Toronto ON M9A 1B7, Canada Geoff Gaherty (Through My Eyepiece) Email: [email protected] Dave Garner (On Another Wavelength) budget. However, applied pressure by Yours Truly, along with Web site: www.rasc.ca Mary Beth Laychak (CFHT Chronicles) others in the astronomical community, made sure that the Telephone: (416) 924-7973 Blair MacDonald (Imager’s Corner) Fax: (416) 924-2911 Curt Nason (Astrocryptic) message got through—we couldn’t afford not to be involved. Blake Nancarrow (Binary Universe) Associate Editor-in-Chief The commitment to provide $243.5 million over ten years John R. Percy (John Percy’s Universe) Nicole Mortillaro Randall Rosenfeld (Art & Artifact) Email: [email protected] ensures that the dome construction can now go ahead. It will Eric Rosolowsky (Dish on the Cosmos) Associate Editor, Research Leslie J. Sage (Second Light) be built by Canadians in Port Coquitlam, B.C., and then will Douglas Hube Rick Saunders (Maker’s Minute) be dismantled for shipping to Hawaii, where it will take its Email: [email protected] David Turner (Reviews) place among the domes atop Mauna Kea. Associate Editor, General Proofreaders Michael Attas Ossama El Badawy Email: [email protected] Margaret Brons The Adaptive Optics portion of Canada’s contribution will be Assistant Editors Angelika Hackett designed and constructed at the National Research Council Michael Allen Terry Leeder Martin Beech Kim Leitch facility in Victoria. The scientists and technicians there have Dave Chapman Michele Arenberg much experience with such designs, as it was there that the Ralph Chou Design/Production Ralph Croning Michael Gatto, Grant Tomchuk very successful Adaptive Optics Bonnette for the Canada- Dave Garner Email: [email protected], France-Hawaii Telescope was developed. Patrick Kelly [email protected] Gail Wise Advertising The very gratifying aspect of this was that the Prime Minister’s Editorial Assistant Julia Neeser Michele Arenburg Email: [email protected] Office (PMO) specifically requested representatives from the Email: [email protected] Printing amateur community—the RASC! Vancouver Centre member Production Manager Canselmdc Dr. Howard Trottier and I were both invited guests at the James Edgar www.cansel.ca Email: [email protected] Prime Minister’s announcement in the Vancouver Space The Journal of The Royal Astronomical Society of Canada is published at an annual Centre near Kitsilano Beach. We joined other important subscription rate of $93.45 (including tax) by The Royal Astronomical Society of Canada. personages: Dr. Raymond Carlberg, University of Toronto; Membership, which includes the publications (for personal use), is open to anyone interested in astronomy. Applications for subscriptions to the Journal or membership in the RASC and Dr. Paul Hickson, UBC; Dr. Christine Wilson, CASCA information on how to acquire back issues of the Journal can be obtained from: President; and Guy Nelson, President and CEO of Empire The Royal Astronomical Society of Canada Industries. 203 – 4920 Dundas St W Toronto ON M9A 1B7, Canada My sound bite for this momentous decision: Email: [email protected] Web site: www.rasc.ca The Royal Astronomical Society of Canada is pleased Telephone: (416) 924-7973 to be part of the large group of people who worked on this Fax: (416) 924-2911 tremendous plan, and especially pleased that the Government Canadian Publications Mail Registration No. 09818 of Canada supports the Long-Range Plan for Astronomy Canada Post: Send address changes to 203 – 4920 Dundas St W, Toronto ON M9A 1B7 and Astrophysics (LRP). Canada Post Publication Agreement No. 40069313 We acknowledge the financial support of the Government of Canada through the Canada Periodical Fund (CPF) for our publishing activities. Canadians can be justifiably proud that their presence will continue to be felt worldwide through the LRP as our leaders push us forward on the leading edge of innovation and © 2015 The Royal Astronomical Society of Canada. discovery. This is a great moment for Canadian astronomy! All rights reserved. ISSN 0035-872X Cert no. SW-COC-005174 V Clear Skies! 94 JRASC | Promoting Astronomy in Canada June / juin 2015 Figure 1 — (Left to right) Dr. Ray Carlberg (Canadian Project Director), Dr. Christine Wilson (President, Canadian Astronomical Society), The Honourable James Moore (Minister of Industry), The Right Honourable Stephen Harper, Guy Nelson (CEO and President, Empire Industries Ltd, Toronto), James Edgar (President, Royal Astronomical Society of Canada) Photo: James Moore News Notes / En manchettes gas pulled apart like taff y under the gravitational forces that result from a merger of two galaxies (Figure 1). Th e immense structures, tens of thousands of light-years long, are found Green fi laments show past quasar activity slowly orbiting a host galaxy, long after the merger was completed. The Hubble Space Telescope has photographed a set of wispy, goblin-green fi laments that are described by researchers as Th e fi rst “green goblin” type of object was found in 2007 by the ephemeral ghosts of quasars that fl ickered to life and Dutch schoolteacher Hanny van Arkel while participating in then faded. Th e glowing structures have looping, helical, the online Galaxy Zoo project.