Sky and Telescope - July 2017 - 2
CONTENTS
THE ESSENTIAL GUIDE TO ASTRONOMY
FEATURES
COVER STORY:
16 The Inside Story
of Neutron Stars
22 Hunting the Galaxy Killer
In roughly half of all galaxies, star
formation has ground to a halt.
What great force has stopped it in
its tracks? By Keith Cooper
28 The Lesson of the
Great Paris Telescope
It was the largest refractor ever
built, with a 49-inch objective lens.
It worked. And then it was sold as
scrap. By Jeff Hecht
34 George Abell's
Ethereal Bubbles
22
July 2017
42
Lunar Almanac & Sky Chart
43
Binocular Highlight
By Mathew Wedel
44
Recover information in your deepsky images with this powerful
technique. By Ron Brecher
Find us on
Facebook & Twitter
ON THE COVER
ON THE COVER
Planetary Almanac
45 Under the Stars
46 Sun, Moon & Planets
By Fred Schaaf
Celestial Calendar
By Alan MacRobert
52 Exploring the Solar System
N ASA / DA N A B ER RY
2
60 Astro-Physics 1100GTO Mount
By Jerry Lodriguss
COLUMNS / DEPARTMENTS
4 Spectrum
By Peter Tyson
6 From Our Readers
8 75, 50 & 25 Years Ago
By Roger W. Sinnott
10 News Notes
14 Cosmic Relief
By David Grinspoon
66 New Product Showcase
72 Astronomer's Workbench
By Jerry Oltion
By Thomas A. Dobbins
54 Deep-Sky Wonders
57
74 Gallery
By Sue French
83 Events Calendar
Going Deep
By Ed Mihelich
84
Focal Point
By Stephen P. Cook
ONLINE
2017 ECLIPSE GUIDE
Prepare for August's total solar
eclipse with maps, educational
resources, observing tips, and more.
skyandtelescope.com/
total-solar-eclipse-august-2017
Neutron stars pack
a Sun's worth of
mass in a citysize sphere.
S&T TEST REPORT
By Fred Schaaf
48
68 Restoring Detail
with Deconvolution
VOL. 134, NO. 1
OBSERVING
41 July's Sky at a Glance
Are you up for a deep-sky challenge?
By Steve Gottlieb
14
Bubble Nebula
OBSERVING GUIDES
Want to observe but don't know
where to begin? Our how-to guides
will help you get the most out of
observing classic celestial sights.
skyandtelescope.com/objects
ASTRONOMY EVENTS
Check out our calendar for upcoming
star parties and other events -
or add your own event to our listings!
skyandtelescope.com/
astronomy-events
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 L Y 2 0 1 7 * SK Y & TELESCOPE
N ASA / ESA / HUBBLE HERITAG E TE A M (STSCI / AUR A)
Astronomers are using X-rays,
gravity, and clever calculations to
discover what lies within these
extraordinary objects. By Feryal Özel
http://www.skyandtelescope.com/total-solar-eclipse-august-2017
http://www.skyandtelescope.com/astronomy-events
http://www.skyandtelescope.com/total-solar-eclipse-august-2017
http://www.skyandtelescope.com/astronomy-events
http://www.skyandtelescope.com/objects
http://www.skyandtelescope.com
Sky and Telescope - July 2017
Table of Contents for the Digital Edition of Sky and Telescope - July 2017
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Sky and Telescope - July 2017 - Cover1
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Sky and Telescope - July 2017 - 1
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