My first Magazine Sky & Telescope - 03.2019

CONTENTS THE ESSENTIAL GUIDE TO ASTRONOMY March 2019 VOL. 137, NO. 3 FEATURES Cover Story: 14 Secrets of Polaris The North Star presents a façade of constancy, but it hides a capricious temperament. By Camille M. Carlisle 20 Spinning Through Space 52 OBSERVING 41 March’s Sky at a Glance 26 Placing the Pleiades Gaia data solve a decades-long controversy about the distance to the Pleiades. By Guillermo Abramson 30 The Herschel Hustle Are you up for the ultimate observing challenge? By Tom Reiland 36 Nurture Your Newt: Bathing Mirrors Cleaning your reﬂ ector’s optics ensures top performance. By Jerry Oltion 62 A Dream Fulﬁ lled The success of Muddy Run Observa- tory depends on local expertise, shared goals, and strong relation- ships. By Robert Naeye 42 Lunar Almanac & Sky Chart 43 Binocular Highlight By Mathew Wedel S&T TEST REPORT 58 Daystar’s Solar Scout 60C By Johnny Horne COLUMNS / DEPARTMENTS 4 Spectrum By Peter Tyson 6 From Our Readers Under the Stars By Fred Schaaf 7 75, 50 & 25 Years Ago By Roger W. Sinnott 46 Sun, Moon & Planets By Fred Schaaf 8 News Notes 44 Planetary Almanac 45 48 Celestial Calendar By S. N. Johnson-Roehr 12 Cosmic Relief By David Grinspoon 52 Exploring the Solar System By Thomas A. Dobbins 68 Astronomer’s Workbench By Jerry Oltion 54 70 New Product Showcase Deep-Sky Wonders By Sue French 72 Gallery 83 Find us on Facebook & Twitter ON THE COVER 84 Focal Point By Joshua Roth ONLINE BEGINNER’S GUIDE Print out our free, 10-page handout to give out at star parties and other community events. skyandtelescope.com/ getting-started Star trails over Anza- Borrego Desert State Park in California PHOTO: DA NIEL J BA RR / G E T T Y IM AG ES 2 Event Calendar IMAGING FOUNDATIONS Want to break into astrophotogra- phy? Learn the fundamentals with Richard Wright, Jr. skyandtelescope.com/ astrophotography WEBINARS Join S&T staff and contributors to learn about astrophotography, equipment, constellations, and other must-knows for amateurs. skyandtelescope.com/classroom SKY & TELESCOPE (ISSN 0037-6604) is published monthly by Sky & Telescope, a division of F+W Media, Inc., 90 Sherman St., Cambridge, MA 02140-3264, USA. Phone: 800-253- 0245 (customer service/subscriptions), 888-253-0230 (product orders), 617-864-7360 (all other calls). Fax: 617-864-6117. Website: skyandtelescope.com. © 2019 F+W Media, Inc. All rights reserved. Periodicals postage paid at Boston, Massachusetts, and at additional mailing ofﬁces. Canada Post Publications Mail sales agreement #40029823. Canadian return address: 2744 Edna St., Windsor, ON, Canada N8Y 1V2. Canadian GST Reg. #R128921855. POSTMASTER: Send address changes to Sky & Telescope, PO Box 420235, Palm Coast, FL 32142-0235. Printed in the USA. M A RCH 2 019 • SK Y & TELESCOPE To capture our dynamic universe, sometimes our telescopes need to show a little dynamism themselves. By Benjamin Skuse

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