Sky and Telescope - December 2016 - 2

December 2016
On the cover:
An ancient
collision - not
fast enough to
do much melting - probably
created Pluto's
five moons.
CASEY REED

Dawn of Discovery at Ceres

44 Planetary Almanac
By Fred Schaaf

Twelve Steps to Infinity

52 Exploring the Moon

The Comets of Edgar Allan Poe

By Fred Schaaf

48 Celestial Calendar
By Alan MacRobert
By Charles A. Wood

54 Deep-Sky Wonders

Targeting the "Tutulemma"
Here's a unique way to capture the total
solar eclipse in 2017. By Tunç Tezel

S &T T E S T R E P O R T

58 Meade's LightBridge
Mini Series
By Tony Flanders

4 Spectrum
By Peter Tyson

7 75, 50 & 25 Years Ago
By Roger W. Sinnott

10 News Notes
By Mario Motta

64 New Product Showcase
70 Astronomer's Workbench
By Jerry Oltion

TUNÇ TEZEL

73 Gallery
84 Focal Point
By John Church &
William Murray

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.
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2

December 2016 sky & telescope

There's more to find online @

SkyandTelescope.com
EXPLORE THE NIGHT BLOG

Follow Contributing Editor Bob
King each week as he takes readers on an adventure in the sky.
SkyandTelescope.com/king

6 Letters

57 Book Review

66

16

By Sue French

ALSO IN THIS ISSUE

Charon and Company

COVER Pluto's five moons proved to be more
STORY complicated than the New Horizons
team ever imagined. By J. Kelly Beatty

66

By Mathew Wedel

46 Sun, Moon & Planets

Poe had some weird ideas. Where did
he get them? By Donald W. Olson &
Shaun B. Ford

36

43 Binocular Highlight

NASA's Dawn spacecraft has found a
world of salt deposits, water ice, and
potentially even signs of an ancient
ocean. By Marc D. Rayman

Use these observing favorites to get
a sense of our place in cosmic history.
By Mathew Wedel

30

42 December's Sky at a Glance

NASA / JPL-CALTECH / UCLA / MPS / DLR / IDA

24

O B S E RV I N G D E C E M B E R

41 In This Section

45 Northern Hemisphere's Sky

F E AT U R E S

16

VOL. 132, NO. 6

ONLINE STORE

Shop our online store for Moon
globes, sky atlases, and more.
ShopatSky.com
PRODUCT VIDEOS

Watch hands-on interviews with
equipment manufacturers and
vendors by Dennis di Cicco.
SkyandTelescope.com/
product-videos
TIPS FOR BEGINNERS

Here's everything you need to
jump into the fun.
SkyandTelescope.com/letsgo

Find us on
Facebook & Twitter


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Sky and Telescope - December 2016

Table of Contents for the Digital Edition of Sky and Telescope - December 2016

Contents
Sky and Telescope - December 2016 - Cover1
Sky and Telescope - December 2016 - Cover2
Sky and Telescope - December 2016 - 1
Sky and Telescope - December 2016 - Contents
Sky and Telescope - December 2016 - 3
Sky and Telescope - December 2016 - 4
Sky and Telescope - December 2016 - 5
Sky and Telescope - December 2016 - 6
Sky and Telescope - December 2016 - 7
Sky and Telescope - December 2016 - 8
Sky and Telescope - December 2016 - 9
Sky and Telescope - December 2016 - 10
Sky and Telescope - December 2016 - 11
Sky and Telescope - December 2016 - 12
Sky and Telescope - December 2016 - 13
Sky and Telescope - December 2016 - 14
Sky and Telescope - December 2016 - 15
Sky and Telescope - December 2016 - 16
Sky and Telescope - December 2016 - 17
Sky and Telescope - December 2016 - 18
Sky and Telescope - December 2016 - 19
Sky and Telescope - December 2016 - 20
Sky and Telescope - December 2016 - 21
Sky and Telescope - December 2016 - 22
Sky and Telescope - December 2016 - 23
Sky and Telescope - December 2016 - 24
Sky and Telescope - December 2016 - 25
Sky and Telescope - December 2016 - 26
Sky and Telescope - December 2016 - 27
Sky and Telescope - December 2016 - 28
Sky and Telescope - December 2016 - 29
Sky and Telescope - December 2016 - 30
Sky and Telescope - December 2016 - 31
Sky and Telescope - December 2016 - 32
Sky and Telescope - December 2016 - 33
Sky and Telescope - December 2016 - 34
Sky and Telescope - December 2016 - 35
Sky and Telescope - December 2016 - 36
Sky and Telescope - December 2016 - 37
Sky and Telescope - December 2016 - 38
Sky and Telescope - December 2016 - 39
Sky and Telescope - December 2016 - 40
Sky and Telescope - December 2016 - 41
Sky and Telescope - December 2016 - 42
Sky and Telescope - December 2016 - 43
Sky and Telescope - December 2016 - 44
Sky and Telescope - December 2016 - 45
Sky and Telescope - December 2016 - 46
Sky and Telescope - December 2016 - 47
Sky and Telescope - December 2016 - 48
Sky and Telescope - December 2016 - 49
Sky and Telescope - December 2016 - 50
Sky and Telescope - December 2016 - 51
Sky and Telescope - December 2016 - 52
Sky and Telescope - December 2016 - 53
Sky and Telescope - December 2016 - 54
Sky and Telescope - December 2016 - 55
Sky and Telescope - December 2016 - 56
Sky and Telescope - December 2016 - 57
Sky and Telescope - December 2016 - 58
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Sky and Telescope - December 2016 - 60
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Sky and Telescope - December 2016 - 63
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Sky and Telescope - December 2016 - 81
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Sky and Telescope - December 2016 - 83
Sky and Telescope - December 2016 - 84
Sky and Telescope - December 2016 - Cover3
Sky and Telescope - December 2016 - Cover4
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