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CONTENTS 2929

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FeaturesFeatures

Features

28 JUICE takes flight

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The flagship mission sets off for Jupiter’s frozen moons this month

34 Mercury returns to twilight

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The tiniest planet is back! We show you how to spot it

40 Cosmology crash course

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As our series continues, we ask: does the Universe have an edge?

60 The new space age

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We report from the international conference on all things space

66 Imaging with

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multi-band filters

Our verdict on eight filters that claim to combat light pollution

Regulars 6 Eye on the sky 11 Bulletin 16 Cutting edge 18 Inside The Sky at Night 20 Interactive 23 What’s on 25 Field of view 26 Subscribe to BBC Sky at Night Magazine 72 Explainer 74 DIY astronomy 98 Q&A: a black hole physicist

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Astrophotography 76 Capture 78 Processing 80 Gallery

Reviews 86 Explore Scientific G400

15x56 roof prism binoculars 90 Serif Affinity Photo 2 software 94 Books 96 Gear

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16 -PAGE CENTRE PULLOUT

The Sky Guide 44 Highlights 46 The big three 48 The planets 50 April’s all-sky chart 52 Moonwatch 53 Comets and asteroids 53 Star of the month 54 Binocular tour 55 The Sky Guide challenge 56 Deep-sky tour 58 April at a glance

4 BBC Sk y at Night Magazine April 2023