CONTENTS
4 ASTRONOMY • SEPTEMBER 2015
24
Starmus will honor
Stephen Hawking in 2016
Next summer, the science festival
will revolve around the life of the
renowned theoretical physicist.
DAVID J. EICHER
28 COVER STORY
Multiverses: Science or
science fiction?
BOB BERMAN explores the strange
ideas that drive theorists to be-
lieve in parallel universes.
34
Ask Astro
Moon musings.
36
The Sky this Month
Totality’s long embrace.
MARTIN RATCLIFFE AND
ALISTER LING
38
StarDome and
Path of the Planets
RICHARD TALCOTT;
ILLUSTRATIONS BY ROEN KELLY
44
Rendezvous with an
evolving comet
As Comet 67P/Churyumov-
Gerasimenko heads closer to the
Sun and grows more active, the
Rosetta and Philae spacecraft
scrutinize its complex behavior.
RICHARD TALCOTT
50
The weirdest star
in the universe
Astronomers dreamt up the idea
of Thorne-Żytkow objects —
dead stars inside dying stars — in
the 1970s. Only recently have
they tracked one down.
YVETTE CENDES
56
Eclipse of the
Super Moon
On September 27, the biggest
Full Moon of the year will pass
through Earth’s shadow.
DEAN REGAS
60
Astronomy’s sixth annual
Star Products
PHIL HARRINGTON
COLUMNS
Strange Universe 10
BOB BERMAN
For Your Consideration 14
JEFF HESTER
Secret Sky 18
STEPHEN JAMES O’MEARA
Observing Basics 22
GLENN CHAPLE
Astro Sketching 68
ERIKA RIX
QUANTUM GRAVITY
Snapshot 9
Astro News 12
IN EVERY ISSUE
From the Editor 6
Letters 10, 14, 22
Web Talk 26
New Products 69
Advertiser Index 70
Reader Gallery 72
Breakthrough 74
FEATURES
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SEPTEMBER 2015
VOL. 43, NO. 9
Dave’s
Universe
The inside
scoop from
the editor
Trips & Tours
Travel the
world with the
staff of
Astronomy
Weekly
Podcast
Observing
targets for all
skywatchers
50 Weirdest
Objects
Explore the
most curious
cosmic oddities
ONLINE
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observing events, stunning photos,
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magazine subscribers.
44
ASTRONOMY:
ROEN KELLY
ON THE COVER
Is our cosmos just one bubble in
an infinite sea? Many cosmologists
believe in such a multiverse even
without physical evidence.
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