Sky & Telescope - April 2023 QR - 2
CONTENTS
THE ESSENTIAL GUIDE TO ASTRONOMY
FEATURES
12 SOFIA's End
NASA's SOFIA observatory came to
an abrupt end in September, leaving
a number of projects unfinished.
By Shannon Hall
20 Springtime Galaxy-Hop
Get your scope out and spend some
time chasing galaxies in southern
Virgo. By Ted Forte
Cover Story:
26 Get Ready for Totality in '24
The Moon's shadow sweeps across
Mexico, the United States, and
eastern Canada next year.
By Fred Espenak & Jay Anderson
36 The Little Stars That Can
Surprising new observations show
novae forging a critical lightweight
metal whose price keeps going up.
By Ken Croswell
60 Gossamer Winds
While every total solar eclipse is
different, past performance can
help you plan for your next
encounter with totality.
By Sean Walker
S&T TEST REPORT
64 ZWO's AM5 Harmonic
Equatorial Mount
By Johnny Horne
ON THE COVER
ONLINE
STARGAZER'S CORNER
Enjoy reader stories of adventures in
astrophotography, eclipse-chasing,
deep-sky marathons, and more!
skyandtelescope.org/
stargazers-corner
Composite image of
the July 2019 eclipse,
seen from Chile
PHOTO: PETR HORÁLEK
2
EXPLORE THE NIGHT BLOG
Follow Contributing Editor Bob King
as he takes readers on an adventure
through the night sky.
skyandtelescope.org/king
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.
APRIL 2023 * SKY & TELESCOPE
MARCH 2018 * SKY & TELESCOPE
12
OBSERVING
41 April'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 Ivan Maly
COLUMNS / DEPARTMENTS
4 Spectrum
By Peter Tyson
6 From Our Readers
7 75, 50 & 25 Years Ago
By Roger W. Sinnott
8 News Notes
69 New Product Showcase
70 Astronomer's Workbench
By Jerry Oltion
72 Book Review
By David Dickinson
74 Beginner's Space
By Gary Seronik
76 Gallery
84 Focal Point
By Alexander Plakha
April 2023
VOL. 145, NO. 4
NASA / SOFIA SCIENCE TEAM / Y. SEO / ESO
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Sky & Telescope - April 2023 QR
Table of Contents for the Digital Edition of Sky & Telescope - April 2023 QR
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Sky & Telescope - April 2023 QR - Cover1
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Sky & Telescope - April 2023 QR - 1
Sky & Telescope - April 2023 QR - Contents
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