Sky & Telescope - USA (2019-09)

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ASTRO TOURISM

Come with us to explore wonders

both on Earth and in the sky.

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IMAGING FOUNDATIONS

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tography with Richard Wright, Jr.

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astrophotography

THIS WEEK’S SKY AT A GLANCE

Our popular column highlights celes-

tial delights for the upcoming week.

Also available as an app — with sky

charts included!

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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.

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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

The fi rst radio image

of a black hole’s

silhouette

ON THE COVER

PHOTO: EVENT HORIZON TELE-

SCOPE COLLABORATION

FEATURES

16 Kepler’s Discoveries

By Shannon Hall and Terri Dubé

Cover Story:

18 The Face of a Black Hole

Here’s how a worldwide team of

scientists detected the “shadow”

of an event horizon.

By Camille M. Carlisle

24 Opportunity’s End

The Martian rover’s spectacular

and heartbreaking saga helped

rewrite textbook knowledge of the

Red Planet. By Shannon Hall

30 Favorite September Sights

Join the author on a saunter

to admire some of his favorite

planetary nebulae. By Ted Forte

36 Imaging on the High Seas

Take advantage of dark skies on your

next luxury cruise. By Greg Redfern

60 Postcards from the Future

Groundbreaking space artist

Chesley Bonestell painted the future

that we live in today.

By Donald Vaughan

S&T TEST REPORT

66 ZWOptical ASIair

By Johnny Horne

COLUMNS / DEPARTMENTS

4 Spectrum

By Peter Tyson

6 From Our Readers

7 75, 50 & 25 Years Ago

By Roger W. Sinnott

8 News Notes

14 Cosmic Relief

By David Grinspoon

40 New Product Showcase

72 Astronomer’s Workbench

By Jerry Oltion

74 Gallery

83 Event Calendar

84 Focal Point

By Michael A. Covington

OBSERVING

41 September’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 Thomas A. Dobbins

54 Deep-Sky Wonders

By Sue French

57 Going Deep

By Dave Tosteson

THE ESSENTIAL GUIDE TO ASTRONOMY

CONTENTS

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September 2019 VOL. 138, NO. 3

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