Astronomy - USA 2021-04)

CONTENTS 24

4 ASTRONOMY • APRIL 2021

16 COVER STORY

The galaxy’s marvelous

rogues and misfits

From ploonets to blanets to

interstellar interlopers, these

nomads defy expectations.

RANDALL HYMAN

24

Trailblazing

astronomers and

their groundbreaking

observatories

The Rubin Observatory and

Roman Space Telescope

are poised to reflect the

accomplishments of their

namesakes and transform our

understanding of the universe.

RANDALL HYMAN

32

Sky This Month

Mars rules the night.

MARTIN RATCLIFFE AND

ALISTER LING

34

Star Dome and

Paths of the Planets

RICHARD TALCOTT;

ILLUSTRATIONS BY ROEN KELLY

40

See spring’s best

Messier objects

Here’s a list of 25 targets to

help you make the most of

your evening.

MICHAEL E. BAKICH

42

Filters for

observing the Sun

Whether using a telescope

or binoculars, solar filters

can help you view the Sun

in its best possible light.

PHIL HARRINGTON

47

Revealing the

2020 eclipse

Though most were unable to

see last year’s total solar eclipse

in person, local astronomers

and websites captured the

cosmic event.

JAY M. PASACHOFF

52

Easy Moon observing

Here’s a strategy that will help

you enjoy our closest celestial

neighbor. MICHAEL E. BAKICH

54

The best scopes for kids

You don’t have to spend a lot to

get a child interested in the sky.

MICHAEL E. BAKICH

62

Ask Astro

Earth’s ultimate fate.

IN EVERY ISSUE

From the Editor 5

Astro Letters 6

Advertiser Index 59

New Products 61

Reader Gallery 64

Breakthrough 66

FEATURES

APRIL 2021

VOL. 49, NO. 4

Astronomy (ISSN 0091-6358, USPS 531-350)

is published monthly by Kalmbach Media

Co., 21027 Crossroads Circle, P. O. Box 1612,

Waukesha, WI 53187–1612. Periodicals postage

paid at Waukesha, WI, and additional offices.

POSTMASTER: Send address changes to

Astronomy, PO Box 8520, Big Sandy, TX 75755.

Canada Publication Mail Agreement #40010760.

Go to http://www.Astronomy.com

for info on the biggest news and

observing events, stunning photos,

informative videos, and more.

ONLINE

FAVORITES

7

QUANTUM GRAVITY

What you need to know

about the universe this

month, including a super-

detailed sunspot image

and Chang’e 5’s return.

COLUMNS

Strange Universe 14

BOB BERMAN

Secret Sky 15

STEPHEN JAMES O’MEARA

Binocular Universe 58

PHIL HARRINGTON

Observing Basics 60

GLENN CHAPLE

ON THE COVER

A black hole in the distance shields

a rogue planet wandering on its

own through a distant galaxy.

MARK A. GARLICK/MARKGARLICK.COM

Dave’s

Universe

The inside

scoop from the

editor.

Sky This

Week

A daily digest

of celestial

events.

News

The latest

updates from

the science

and the hobby.

Trips and

Tours

Travel the world

with the staff of

Astronomy.

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