Sky & Telescope - December 2019 - 2

CONTENTS

THE ESSENTIAL GUIDE TO ASTRONOMY

December 2019

VOL. 138, NO. 6

FEATURES

Cover Story:
16 The Neglected Planets
Decades after a lone spacecraft ﬂew
by, the solar system's ice giants and
their many moons still guard plenty
of secrets.
By Ken Croswell

Storms, radiation, and dust combine
to create a deadly environment on
the Red Planet.
By Jim Bell

30 Sketching Superbubbles

22
OBSERVING
41 December's Sky at a Glance
By Diana Hannikainen

S&T TEST REPORT
66 GSO's 10-inch f/12
Classical Cassegrain
By Dennis di Cicco

42 Lunar Almanac & Sky Chart
COLUMNS / DEPARTMENTS

Join the author as he explores the
Orion-Eridanus Superbubble region,
sketchpad at the ready.

43 Binocular Highlight
By Mathew Wedel

By Mel Bartels

44 Planetary Almanac
45 Under the Stars
By Fred Schaaf

36 Hobby Killers
Here's how to avoid buying an
expensive doorstop.
By Jerry Oltion

58 Just Over a Century Ago
What could the reading public know
about astronomy in 1900?
By Klaus Brasch

From Our Readers

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

48 Celestial Calendar
By S. N. Johnson-Roehr

57 Book Review
By Richard S. Wright, Jr.

52 Exploring the Moon
By Charles A. Wood

70 New Product Showcase
72 Astronomer's Workbench
By Jerry Oltion
74 Gallery
84 Focal Point
By Bryan Wang

ONLINE

BEGINNERS' GUIDE
Print out our free, 10-page handout
to give out at star parties and other
community events.
skyandtelescope.com/
getting-started

UR A NUS A ND NEPT UNE: N ASA /
JPL- CA LTECH (2)

10 News Notes

Find us on
Facebook & Twitter

No spacecraft has
visited Uranus or Neptune since the 1980s.

Spectrum
By Peter Tyson

46 Sun, Moon & Planets
By Fred Schaaf

54 Deep-Sky Wonders
By Sue French

ON THE COVER

EXPLORE THE NIGHT BLOG
Follow Contributing Editor Bob King
as he takes readers on an adventure
through the night sky.
skyandtelescope.com/king

INTERACTIVE SKY CHART
Find out what the sky looks like for
your time and place. You can also
print the chart as a handout.
skyandtelescope.com/
interactive-sky-chart

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22 Martian Weather Report

http://www.skyandtelescope.com/king http://www.skyandtelescope.com/getting-started http://www.skyandtelescope.com/interactive-sky-chart http://www.skyandtelescope.com/getting-started http://www.skyandtelescope.com/interactive-sky-chart http://www.skyandtelescope.com

Sky & Telescope - December 2019

Table of Contents for the Digital Edition of Sky & Telescope - December 2019