Sky & Telescope - December 2020 - 2

CONTENTS

THE ESSENTIAL GUIDE TO ASTRONOMY

December 2020

VOL. 140, NO. 6

FEATURES

Cover Story:
14 Get Ready for the Geminids
"It's the most wonderful time of the
year . . ." to see meteors! By Joe Rao

20 The Caldwell Catalog
Turns 25

28 Specks Between the Stars
When thinking about cosmic
wonders, we often wrongly sweep
interstellar dust under the rug.
By Christopher Crockett

34 Follow the Carbon
There's another ingredient besides
water that's crucial to the recipe for
life. By Edwin Bergin

58 What Does Your Lawn Think
of a Solar Eclipse?
Humans aren't the only lifeforms
that notice totality.
By David Billesbach &
Timothy Arkebauer

60 Measuring the Stars
Here's how you can contribute to
the science of astronomy.
By Richard Berry

34

OBSERVING
41 December's Sky at a Glance
By Diana Hannikainen
42 Lunar Almanac & Sky Chart

S&T TEST REPORT
66 Unistellar's eVscope
By Richard Tresch Fienberg
COLUMNS / DEPARTMENTS

43 Binocular Highlight
By Mathew Wedel

4

Spectrum
By Peter Tyson

44 Planetary Almanac

6

From Our Readers

45 Under the Stars
By Fred Schaaf

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

46 Sun, Moon & Planets
By Fred Schaaf

8 News Notes

48 Celestial Calendar
By Bob King

57 Book Review
By Nick Kanas
72 New Product Showcase

52 Exploring the Moon
By Charles A. Wood
54 Deep-Sky Wonders
By Sue French

74 Astronomer's Workbench
By Jerry Oltion
76 Gallery
84 Focal Point
By Dara Norman

ON THE COVER

ONLINE

ASTRONOMY Q&A
From dark matter and black holes
to comets and planets, get your
astronomy 101 questions answered.
skyandtelescope.org/faq

Composite image of
the 2018 Geminid
meteor shower
PHOTO: PE TR HOR Á LEK

2

ONLINE STORE
Shop our online store for Moon and
planet globes, sky atlases, and
more, all made or chosen by the
staff of Sky & Telescope.
shopatsky.com

ASTROPHOTO GALLERY
Enjoy readers' best images and
upload your own to share with your
fellow enthusiasts.
skyandtelescope.org/gallery

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. ©2020 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 420235, Palm
Coast, FL 32142-0235. Printed in the USA.

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USGS / N ASA / L A NDSAT 7

This popular list of observing targets
is marking its first quarter-century.
By Mathew Wedel


http://www.skyandtelescope.org/gallery http://www.skyandtelescope.org/faq http://www.shopatsky.com http://www.skyandtelescope.org http://www.shopatsky.com

Sky & Telescope - December 2020

Table of Contents for the Digital Edition of Sky & Telescope - December 2020

Contents
Sky & Telescope - December 2020 - Cover1
Sky & Telescope - December 2020 - Cover2
Sky & Telescope - December 2020 - 1
Sky & Telescope - December 2020 - Contents
Sky & Telescope - December 2020 - 3
Sky & Telescope - December 2020 - 4
Sky & Telescope - December 2020 - 5
Sky & Telescope - December 2020 - 6
Sky & Telescope - December 2020 - 7
Sky & Telescope - December 2020 - 8
Sky & Telescope - December 2020 - 9
Sky & Telescope - December 2020 - 10
Sky & Telescope - December 2020 - 11
Sky & Telescope - December 2020 - 12
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