Eclipse from the See Sirius B: The Nearest Spot the Other EDGE OF SPACE p. 66 WHITE DWARF p. 30 BLUE PLANETS p. 50 THE ESSENTIAL GUIDE TO ASTRONOMY What Put the Bang in the Big Bang p. 22 Telescope Alignment Made Easy p. 64 Explore the Nearby Milky Way p. 32 How to Draw the Moon p. 54 OCTOBER 2013 Cosmic Gold Rush Racing to fi nd exploding stars p. 16 Visit SkyandTelescope.com Download Our Free SkyWeek App FC Oct2013_J.indd 1 8/2/13 2:47 PM “I can’t say when I’ve ever enjoyed owning anything more than my Tele Vue products.” — R.C, TX Tele Vue-76 Why Are Tele Vue Products So Good? Because We Aim to Please! For over 30-years we’ve created eyepieces and telescopes focusing on a singular target; deliver a cus- tomer experience “...even better than you imagined.” Eyepieces with wider, sharper fields of view so you see more at any power, Rich-field refractors with APO performance so you can enjoy Andromeda as well as Jupiter in all their splendor. 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GEHRZ There’s more to find online @ 47 Northern Hemisphere’s Sky FEATURES By Fred Schaaf SkyandTelescope.com 16 The Great Supernova Race 48 Sun, Moon & Planets In the eff ort to discover exploding COVER By Fred Schaaf MONTHLY SKY PODCAST STORY stars, professionals have taken the Listen as we guide you through lead, but amateurs have managed to 50 Celestial Calendar By Alan MacRobert this month’s celestial sights. stay in the game. SkyandTelescope.com/podcasts By Robert Zimmerman 54 Exploring the Moon By Charles A. Wood 22 Back to the Big Bang 56 Deep-Sky Wonders A faint signal hidden in the universe’s By Sue French earliest light might reveal what hap- pened in the fi rst moment after cos- S&T TEST REPORT mic birth. By Bruce Lieberman 60 S&T Test Report By Sean Walker 30 October’s Dawn Window for Sirius B ALSO IN THIS ISSUE Sirius in October? If you’d like to try for its legendary white dwarf 6 Spectrum By Robert Naeye companion — easier to see now than in decades — here’s why to 8 Letters SKY set your alarm clock. WEEK 9 75, 50 & 25 Years Ago NASA / JPL By Alan Whitman By Roger W. Sinnott 10 News Notes 32 Observing the Milky Way, SKY AT A GLANCE Part II: Scutum to 40 Book Review Our popular column by Alan By Gary Seronik Cassiopeia MacRobert highlights celestial The autumn Milky Way is rich in 42 New Product Showcase delights for the upcoming week. nearby clusters and nebulae. SkyandTelescope.com/ataglance 64 Telescope Workshop By Craig Crossen By Gary Seronik 77 Gallery FIND PRODUCTS & SERVICES 66 Chasing Totality Our easy-to-use directory will from the Stratosphere 86 Focal Point help you fi nd what you need. Braving the Australian Outback, an By Henry G. Stratmann SkyandTelescope.com/directory international amateur team launched a balloon to catch last November’s solar eclipse. By Catalin°° Beldea & Joe Cali SKY & TELESCOPE (ISSN 0037-6604) is published monthly by Sky & TIPS FOR BEGINNERS Telescope Media, LLC, 90 Sherman St., Cambridge, MA 02140-3264, USA. Phone: 800-253-0245 (customer service/subscriptions), 888- New to astronomy? 253-0230 (product orders), 617-864-7360 (all other calls). Fax: 617- Here’s everything you need 72 The Man Who 864-6117. Website: SkyandTelescope.com. © 2013 Sky & Telescope Illustrated the Heavens Media, LLC. All rights reserved. Periodicals postage paid at Boston, to jump into the fun. H. A. Rey, co-creator of Curious Massachusetts, and at additional mailing offi ces. Canada Post SkyandTelescope.com/letsgo Publications Mail sales agreement #40029823. Canadian return George, turned his talents skyward address: 2744 Edna St., Windsor, ON, Canada N8Y 1V2. Canadian to demystify the stars. GST Reg. #R128921855. POSTMASTER: Send address changes Find us on to Sky & Telescope, PO Box 420235, Palm Coast, FL 32142-0235. 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OCTOBER PODCAST OBSERVING AUDIO SKY TOUR HIGHLIGHTS Sign up for Newsletters, AstroAlerts, and Observing Tools THIS WEEK’S DOWNLOAD OUR Shop @ Sky Sky at a Glance SKYGAZING APPS Updated Elevation Mars Globe For Droid DIGITAL BACK ISSUES: Find us on Facebook June, July, August, and September & Twitter October 2013 sky & telescope ONLINE PHOTO GALLERY Niels V. Christensen imaged M51 in March and April of this year. See more beautiful astrophotos, or submit your own, to our online Photo Gallery. Robert Naeye Spectrum Founded in 1941 by Charles A. Federer, Jr. and Helen Spence Federer The Essential Guide to Astronomy EDITORIAL Money Spent Down Here Editor in Chief Robert Naeye Senior Editors Dennis di Cicco, Alan M. MacRobert Hed.GillSans.30 Associate Editor Tony Flanders Imaging Editor Sean Walker Assistant Editor Camille M. Carlisle This is going to sound strange, but I had a lot of fun at July’s Green Web Editor Monica Young Bank Star Quest even though the nights were clouded out. This star party is Editor Emeritus Richard Tresch Fienberg Senior Contributing Editors J. Kelly Beatty, Roger W. Sinnott held at the National Radio Astronomy Observatory in Green Bank, West Vir- Contributing Editors Jim Bell, Trudy Bell, John Bortle, Greg Bryant, Paul Deans, ginia. NRAO generously allows GBSQ attendees to tour inside the security Thomas A. Dobbins, David W. Dunham, Alan Dyer, Tom Field, Ted Forte, gate for close-up views of the antennas. NRAO also permits the use of many Sue French, Steve Gottlieb, David Grinspoon, Paul J. Heafner, Ken Hewitt- White, Johnny Horne, E. C. Krupp, Emily Lakdawalla, David H. Levy, of its facilities.