2 M A RC H 2 018 • SK Y & TELESCOPE

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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), 617-864-7360 (all other calls). Fax: 617-864-6117. Website: skyandtelescope.com. Store website: shopatsky.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.

ONLINE

Jupiter’s southern hemisphere delights with exotic storms.

ON THE COVER

NASA / MSSS / DAVID MARRIOTT

FEATURES

Cover Story:14 JunoCam at Jupiter: Where Science Meets Art Amateur processing has revealed this fantastic world from a unique perspective.

By Candice Hansen-Koharcheck

22 Binary Orbits Explored Follow the author on a celestial tour of some of his favorite binary pairs.

By Phillip Kane

28 A Relatively Important Eclipse A century ago an eclipse revealed to the world that the universe bends to Einstein’s whim.

By Benjamin Skuse

34 The Allure of Betelgeuse Astronomers are itching to know when this red supergiant will go supernova, but a clear answer eludes them. By Peter Tyson

64 Insect Eyes on the Deep Sky A team of astronomers uses an innovative approach to create the world’s fastest telescope system.

By Richard S. Wright, Jr.

S&T TEST REPORT

60 Omegon Mini Track LX2 By Alan Dyer

COLUMNS / DEPARTMENTS

4 Spectrum By Peter Tyson 6 From Our Readers 7 75, 50 & 25 Years Ago By Roger W. Sinnott 8 News Notes 12 Cosmic Relief By David Grinspoon 70 Astronomer’s Workbench By Jerry Oltion 72 Gallery 83 Event Calendar 84 Focal Point By Francine Jackson

OBSERVING

41 May’s Sky at a Glance 42 Lunar Almanac & Sky Chart 43 Binocular Highlight By Mathew Wedel 44 Planetary Almanac 45 Under the Stars By Fred Schaaf 46 Sun, Moon & Planets By Fred Schaaf 48 Celestial Calendar By S. N. Johnson-Roehr 52 Exploring the Solar System By Richard Jakiel 54 Deep-Sky Wonders By Sue French 57 Going Deep By Steve Gottlieb

T H E E S S E N T I A L G U I D E TO A S T R O N O M Y

CONTENTS

2 M AY 2 019 • SK Y & TELESCOPE

May 2019 VOL. 137, NO. 5

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