Australian Sky & Telescope - 02.2019 - 03.2019

42 AUSTRALIAN SKY & TELESCOPE February | March 2019

I

assume that like most binocular observers, you’ve probably looked

at the Pleiades and Hyades many times in recent months. I often

zip between the two nearby clusters to compare them. In doing so,

for a long time I passed over a rich and beautiful star field that lies

between them.

About 5° north of the Hyades, a scattering of 4th- to 6th-magnitude

stars is spread southwest to northeast over about 4°. Many of the stars

fall into pairs that are coincidentally aligned southwest to northeast as

well. Collectively they make an elongated dagger shape, like a swordfish

or a vintage rocket ship. Omega2 (ω) Tauri forms the nose, 51 and 56

Tauri constitute the northern border, and HD 27639 and HD 27742

form the southern edge. From HD 27742, a nice chain of faint stars

runs north to Kappa1 (κ) and Kappa2 Tauri. With a separation of

about 345′′, Kappa Tauri makes a fine binocular double. From Kappa,

look for a tall shark tail formed by Upsilon (υ) Tauri and 72 Tauri to the

north, and HD 28226 to the south.

Most of these are main sequence and subgiant stars that lie

between 100 and 500 light-years away. Like the members of the

Hyades and Pleiades, they’re our neighbours in the Orion Spur of

the Milky Way. The exception is HD 27639, an M-class red giant that

lies 2,300 light-years away. HD 27639 forms a tight binary with HD

27640. Their separation is only 1.9′′, which makes them a challenge

even for telescopes. If you revisit this area with a scope, have a close

look at that star chain between HD 27742 and Kappa Tauri, and see

if you can spot the 11th-magnitude star that sits exactly halfway

between Kappa^1 and Kappa^2 Tauri.

■ MATT WEDEL wonders what else he’s missed in the areas near his

favourite objects.

Between the clusters

–1

Star

magnitudes

0

1

2

3

4

WHEN

Late January 1 a.m.

Early February Midnight

Late February 11 p.m.

Early March 10 p.m.

These are daylight saving times.

Subtract one hour if daylight

saving is not applicable.

HOW:Go outside within an hour

orsoofatimelistedabove.Hold

themapoutinfrontofyouand

turn it around so the label for the

directionyou’refacing(suchas

west or northeast) is right-side up.

Thecurvededgerepresentsthe

horizon, and the stars above it on

the map now match the stars in

frontofyouinthesky.Thecentre

ofthemapisthezenith,thepoint

in the sky directly overhead.

FOR EXAMPLE:Tur n the

maparoundsothelabel“Facing

NE”isright-sideup.Abouthalfway

fromtheretothemap’scentreis

thebrightstarProcyon.Goout

and look northeast halfway from

horizontal to straight up.

There’s Procyon!

NOTE:The map is plotted for

35° south latitude (for example,

Sydney, Buenos Aires, Cape

Town). If you’re fa r nor th of the re,

stars in the northern part of the

sky will be higher and stars in the

south lower. Far south of 35° the

reverse is true.

14

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IP

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VIRGO

α

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π

Spica

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EN

ONLINE

You can get a real-time sky chart

for your location at

skychart.skyandtelescope.com/

skychart.php

USING THE

STAR CHART

Aldebaran

ω^2

51

φ

72

HD 27742

HD 28226

HD 27639 / HD 27640

γ

56

χ

κκ^12

υ

ε

α

τ

TAURUS

Hyades

5 ° binoc

ular

(^) vie
w
BINOCULAR HIGHLIGHT by Mathew Wedel
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