Sky & Telescope - December 2023 - 2
CONTENTS
December 2023
THE ESSENTIAL GUIDE TO ASTRONOMY
FEATURES
Cover Story:
12 The Drama Next Door
The Andromeda Galaxy is a giant
spiral like the Milky Way but has
had a surprisingly different - and
tumultuous - past. By Ken Croswell
18 Distant Dozen
Observe the farthest galaxies found
visually in the NGC and IC
catalogs. By Jimi Lowrey
26 E. M. Antoniadi:
The Astronomer Who
Decoded Mars
This Greek-French astronomer is
perhaps history's greatest visual
planetary observer.
By William Sheehan
34 Shields Up
Scientists are second-guessing the
role magnetic fields play in
protecting planets.
By Camille M. Carlisle
60 Modding Your Telescope
Take charge of your scope's design
and make it perform better than
ever. By Jerry Oltion
S&T TEST REPORT
66 Player One Astronomy's
Poseidon-M PRO
By Richard S. Wright, Jr.
ON THE COVER
ONLINE
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.org/
interactive-sky-chart
North-right composite
image of M31 with its
galactic friends
PHOTO: SEAN WALKER / MDW
SURVEY
2
STARGAZER'S CORNER
Enjoy reader stories of adventures in
astrophotography, eclipse-chasing,
deep-sky marathons, and more!
skyandtelescope.org/
stargazers-corner
DIGITAL EDITION
Use the email connected to
your subscription to read
our latest digital edition.
skyandtelescope.org/
digital
SKY & TELESCOPE (ISSN 0037-6604) is published monthly by AAS Sky Publishing, LLC, owned by the American Astronomical Society, 1667 K Street NW, Suite 800, Washington, DC
20006, USA. Phone: 800-253-0245 (customer service/subscriptions), 617-500-6793 (all other calls). Website: skyandtelescope.org. Store website: shopatsky.com. ©2023 AAS Sky
Publishing, LLC. All rights reserved. Periodicals postage paid at Washington, DC, 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 219, Lincolnshire,
IL, 60069-9806. Printed in the USA. Sky & Telescope maintains a strict policy of editorial independence from the AAS and its research publications in reporting on astronomy.
DECEMBER 2023 * SKY & TELESCOPE
MARCH 2018 * SKY & TELESCOPE
34
OBSERVING
41 December's Sky at a Glance
By Diana Hannikainen
42 Lunar Almanac & Sky Chart
43 Binocular Highlight
By Mathew Wedel
44 Planetary Almanac
45 Evenings with the Stars
By Fred Schaaf
46 Sun, Moon & Planets
By Gary Seronik
48 Celestial Calendar
By Bob King
52 Exploring the Solar System
By Charles A. Wood
54 First Exposure
By Tony Puerzer
57 Going Deep
By Scott Harrington
COLUMNS / DEPARTMENTS
4 Spectrum
By Peter Tyson
6 From Our Readers
7 75, 50 & 25 Years Ago
By Roger W. Sinnott
8 News Notes
65 Book Review
By Peter Tyson
70 New Product Showcase
72 Astronomer's Workbench
By Jerry Oltion
74 Beginner's Space
By Diana Hannikainen
76 Gallery
84 Focal Point
By Ted Forte
VOL. 146, NO. 6
ELENA11 / SHUTTERSTOCK, SOURCE: NASA
http://skyandtelescope.org/stargazers-corner
http://skyandtelescope.org/digital
http://skyandtelescope.org/interactive-sky-chart
http://skyandtelescope.org/interactive-sky-chart
http://skyandtelescope.org/stargazers-corner
http://skyandtelescope.org/digital
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http://www.shopatsky.com
Sky & Telescope - December 2023
Table of Contents for the Digital Edition of Sky & Telescope - December 2023
Contents
Sky & Telescope - December 2023 - Cover1
Sky & Telescope - December 2023 - Cover2
Sky & Telescope - December 2023 - 1
Sky & Telescope - December 2023 - Contents
Sky & Telescope - December 2023 - 3
Sky & Telescope - December 2023 - 4
Sky & Telescope - December 2023 - 5
Sky & Telescope - December 2023 - 6
Sky & Telescope - December 2023 - 7
Sky & Telescope - December 2023 - 8
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Sky & Telescope - December 2023 - Cover3
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