Sky and Telescope - June 2017 - 2
CONTENTS
THE ESSENTIAL GUIDE TO ASTRONOMY
FEATURES
12 Seven Earth-Size
Planets Orbit Dim Star
Several of TRAPPIST-1's worlds
might have the potential for liquid
surface water. By Camille M. Carlisle
24
The strange dips, dives & dimmings
of an otherwise ordinary star defy
most - but not all - explanations.
June 2017
By Benjamin Montet & Tabetha Boyajian
OBSERVING
24 The Square Kilometre Array
Spread across two continents, the
SKA will be the largest astronomical
facility ever built. By Govert Schilling
32 Who Discovered
the Ring Nebula?
All the books name the wrong
"discoverer" for this iconic object.
VOL. 133, NO. 6
41
June's Sky at a Glance
42
Lunar Almanac & Sky Chart
43
Binocular Highlight
By Mathew Wedel
44
Planetary Almanac
COVER STORY:
S&T TEST REPORT
58 102-mm FCD100
Triplet APO Refractor
By Alan Dyer
COLUMNS / DEPARTMENTS
45 Under the Stars
By Fred Schaaf
By Don Olson & Giovanni Maria Caglieris
46 Sun, Moon & Planets
64 The Dark Wolf of Summer
Stay up late to track down these
absorption nebulae in Lupus.
By Richard P. Wilds
70 Phantoms of the Deep Sky
Hunt down molecular clouds and
other elusive targets.
By Richard Jakiel
By Fred Schaaf
48
Celestial Calendar
By Alan MacRobert
52 Exploring the Moon
By Charles A. Wood
54 Deep-Sky Wonders
By Sue French
Find us on
Facebook & Twitter
ON THE COVER
ON THE COVER
ROBERT GENDLER / STOCKTREK
IMAGES / GETTY IMAGES
2
4 Spectrum
By Peter Tyson
6 From Our Readers
7 75, 50 & 25 Years Ago
By Roger W. Sinnott
8 News Notes
38 Astronomer's Workbench
By Jerry Oltion
57 Book Review
By Monica Young
62 New Product Showcase
74 Gallery
84 Focal Point
By Camille M. Carlisle
ONLINE
EXPLORE THE NIGHT BLOG
Follow Contributing Editor Bob King
each week as he takes readers on an
adventure in the sky.
skyandtelescope.com/king
The vast hydrogen
petals of M57 glow
red in this colorized
image.
14
MeerKAT dishes in South Africa's Great Karoo
SKY ON THE GO
Find information about all our
skygazing apps, from SkyWeek to
JupiterMoons.
skyandtelescope.com/apps
ONLINE STORE
Shop our store for all your astronomy
needs - from sky atlases and globes
to posters and more.
shopatsky.com
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. ©2017 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.
J U N E 2 0 1 7 * SK Y & TELESCOPE
GOVERT SCHILLING
16 The Most Mysterious
Star in the Galaxy
http://www.skyandtelescope.com/king
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http://www.shopatsky.com
http://www.skyandtelescope.com
Sky and Telescope - June 2017
Table of Contents for the Digital Edition of Sky and Telescope - June 2017
Contents
Sky and Telescope - June 2017 - Cover1
Sky and Telescope - June 2017 - Cover2
Sky and Telescope - June 2017 - 1
Sky and Telescope - June 2017 - Contents
Sky and Telescope - June 2017 - 3
Sky and Telescope - June 2017 - 4
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