Sky and Telescope - July 2018 - 2

CONTENTS

THE ESSENTIAL GUIDE TO ASTRONOMY

July 2018

VOL. 136, NO. 1

FEATURES
SPECIAL ISSUE: MARS

Mars's Lost Atmosphere
NASA's MAVEN mission has
conﬁrmed how our planetary
neighbor lost its protective gas
envelope. By Bruce Jakosky

Wonder what to see now that the
Red Planet is at its biggest and
brightest? Read on for the best tips.
By Bob King

22
OBSERVING

S&T TEST REPORT

41 July's Sky at a Glance

62 QHYCCD PoleMaster
By Alan Dyer

42 Lunar Almanac & Sky Chart

28 Canal Mania
Earthly events inﬂuenced how
astronomers perceived the Martian
landscape a century ago.

43 Binocular Highlight
By Mathew Wedel

By Klaus Brasch

44 Planetary Almanac

34 Litter in Orbit: How to
Clean Up Space Junk
Thousands of pieces of debris orbit
Earth, and it's going to take a
coordinated effort to solve the
problem. By Jonathan McDowell

66 Messier 27: The First
Planetary Nebula
Explore this complex object through
your telescope with the help of an
experienced observer's ever-soelaborate sketches.
By Howard Banich

COLUMNS / DEPARTMENTS

From Our Readers

45 Under the Stars
By Fred Schaaf

75, 50 & 25 Years Ago
By Roger W. Sinnott

46 Sun, Moon & Planets
By Fred Schaaf

News Notes

Celestial Calendar
By S. N. Johnson-Roehr

52 Exploring the Solar System
By Thomas A. Dobbins
54 Deep-Sky Wonders
By Sue French
58 Going Deep
By Ken Hewitt-White

M A RS: N ASA / JPL- CA LTECH;
T Y PE: © CORBIS / CORBIS VIA
G E T T Y IM AG ES

57 New Product Showcase
72 Astronomer's Workbench
By Jerry Oltion
74 Gallery
83 Event Calendar

ONLINE

EXPLORE THE NIGHT BLOG
Follow Contributing Editor Bob King
each week as he takes readers on
an adventure through the night sky.
skyandtelescope.com/king
This Viking Orbiter
mosaic shows off
Valles Marineris.

12 Cosmic Relief
By David Grinspoon

84 Focal Point
By Kyle Jeter

Find us on Facebook & Twitter
ON THE COVER

4 Spectrum
By Peter Tyson

PRODUCT VIDEOS
Watch hands-on interviews with
equipment manufacturers and vendors by expert Dennis di Cicco.
skyandtelescope.com/
product-videos

BUILD COMMUNITY
Seeking fellow enthusiasts? Find
clubs and other organizations in your
area, or add yours to our listings.
skyandtelescope.com/
astronomy-clubs-organizations

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: 800-2530245 (customer service/subscriptions), 888-253-0230 (product orders), 617-864-7360 (all other calls). Fax: 617-864-6117. Website: skyandtelescope.com. ©2018 F+W Media, Inc.
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ESA / DLR / FU BERLIN / BILL DUNFORD

22 Mars the Mighty Returns

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Sky and Telescope - July 2018

Table of Contents for the Digital Edition of Sky and Telescope - July 2018