Sky and Telescope - February 2017 - 2

CONTENTS

THE ESSENTIAL GUIDE TO ASTRONOMY

FEATURES

16 Anatomy of a Black Hole
18 Of Black Holes & Galaxies
How much influence do supermassive black holes have on their
galaxies, or vice versa?

18

M106

By Camille M. Carlisle

COVER STORY:

26 Mega-Eye on the Sky
Completed last September, China's
FAST has eclipsed Arecibo as the
largest single-dish radio telescope in
the world. By Renjiang Xie

February 2017
OBSERVING

VOL. 133, NO. 2

S&T TEST REPORT
64 Pentax's "Astro" DSLR

41

February's Sky at a Glance

42

Lunar Almanac & Sky Chart

43

Binocular Highlight
By Mathew Wedel

4 Spectrum

Planetary Almanac

6 From Our Readers

By Alan Dyer

COLUMNS / DEPARTMENTS

Here's how to shoot from the
darkest skies in the U.S. Southeast.
(Don't forget the drinking water.)

44

45 Under the Stars
By Fred Schaaf

By Richard S. Wright, Jr.

36 The Supernova of a Lifetime
Thirty years later, Supernova 1987A
continues to develop and surprise.

46

Sun, Moon & Planets
By Fred Schaaf

By Peter Tyson

8 75, 50 & 25 Years Ago
By Roger W. Sinnott

10 News Notes
57 Book Review

48 Celestial Calendar

By S. N. Johnson-Roehr

By Alan MacRobert

By Robert P. Kirshner

68 New Product Showcase

58 Gemini City Sights
The deep-sky treasures scattered
across the Twins look great in backyard scopes. By Ken Hewitt-White

52 Exploring the Moon
By Charles A. Wood

70 Astronomer's Workbench
By Jerry Oltion

54 Deep-Sky Wonders
By Sue French

72 Gallery
84 Focal Point

Find us on Facebook & Twitter

ON THE COVER
ON THE COVER

ONLINE

ORBITAL PATH PODCAST
Explore all things astronomy with
NASA's Michelle Thaller in her
weekly podcast.
skyandtelescope.com/orbital-path
China has completed its
500-m-wide radio dish,
now the largest singledish scope of its kind.
LIU XU / XINHUA

2

By Laurie E. Jasinski

EQUIPMENT GUIDES
Find advice on choosing the best
tools for your backyard adventures.
skyandtelescope.com/
equipment/basics

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.

F E B R U A R Y 2 0 1 7 * SK Y & TELESCOPE

N ASA / CXC / JPL- CA LTECH / STSCI / NSF / NR AO / V L A

32 Imaging Adventure:
Dry Tortugas


http://www.skyandtelescope.com/equipment/basics http://www.skyandtelescope.com/orbital-path http://www.shopatsky.com http://www.skyandtelescope.com

Sky and Telescope - February 2017

Table of Contents for the Digital Edition of Sky and Telescope - February 2017

Contents
Sky and Telescope - February 2017 - Cover1
Sky and Telescope - February 2017 - Cover2
Sky and Telescope - February 2017 - 1
Sky and Telescope - February 2017 - Contents
Sky and Telescope - February 2017 - 3
Sky and Telescope - February 2017 - 4
Sky and Telescope - February 2017 - 5
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