Australian Sky & Telescope - April 2018

4 AUSTRALIAN SKY & TELESCOPE April 2018

REGULARS

5Spectrum

8Newsnotes

12 Discoveries

13 AS&T bookshop

FEATURES

14 Earth’sevolvingmagnetic

field

We depend upon a global

electromagnetic bubble to protect us

from hazardous space radiation. Is

that invisible field wavering?

By Robert Naeye

20 TESS–theTransiting

Exoplanet Survey Satellite

NASA’s next planet-hunting mission,

theTransitingExoplanetSurvey

Satellite, will survey roughly 200,

nearby stars for signs of Earth-like

alien worlds.

By Sara Seager

26 Science in the stratosphere

Balloon-borne instruments give

astronomers a taste of space without

theneedforexpensiverocketsor

satellites.

By Laura Fissel

36 The ancient circle of animals

TheMoontravelsamong12lively

constellations. Where did they all

come from, and what do their names

mean?

By Craig Crossen

58 My dad and the telescope

A father’s love for his son has found

new expression in amazing images of

the southern sky.

By Michael Sidonio

Contents

April 2018 ISSUE 108, VOL. 14 NO. 3

OBSERVING & EXPLORING

42 Binocular highlight

Theta Car’s hot, blue radiance.

By Jonathan Nally

44 Under the stars

Sirius isn’t Canis Major’s only ‘star’.

By Fred Schaaf

46 Sun, Moon and planets

A good time to observe Mercury.

By Jonathan Nally

47 Meteors

The ever-reliable Eta Aquariids.

By Con Stoitsis

48 Double star notes

WanderingwestthroughCentaurus.

By Ross Gould

49 Variable stars

V Pyxidis and its perplexing changes.

By Alan Plummer

50 Comets

C/2016 R2 puts on a remarkable display.

By David Seargent

51 Targets

Swim with the Crab and Water Monster.

By Sue French

54 Exploring the Moon

Revealing the Moon’s watery secrets.

By Charles A. Wood

56 Exploring the Solar System

A crazy theory about Venus.

By J. Kelly Beatty

P.26 Astronomy by balloon

P.20 NASA’s new planet hunter