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S
E
N
T
H
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STAR BRI
SERVAT
AS AND
IN THE N IONS ABOUT T
HE STAR
IGHT SK
S
Y.
EXPERIE
EXTEND
EXPLAN NCES AND PER THEIR
ATIONS
SONAL
OF THE
WORLD
NAT
TH
PLAY, A ROUGH EXPLO URAL
ND ASK
RA
IN
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SEEK A
IONS.
ND DES
CRIBE
SIMPLE
PATTER
PHYSIC
N
S
IN
AL PHE
NOMEN
A.
Even the faintest stars are not the same brightness as each other, when zooming
in on the ‘Jewel Box’ in the Southern Cross (Hubble Space Telescope). Credit: ESO.
at night
Looking up at the stars
from
ge
we notice that they ran
t. Our
fain
y
ver
y,
quite bright to ver
e the
um
ass
to
is
t
inc
inst
automatic
esses,
htn
brig
nt
ere
diff
e
hav
stars
far
and not to think about how
us.
m
away they are fro
t our Sun
But if we remember tha
ely
hug
s
is a star, and it appear
rs,
sta
e
tim
ht
brighter than nig
st
mu
rs
sta
to
ces
tan
dis
then the
y seem
the
ht
brig
how
ct
affe
also
to us.
same
Two stars that appear the
fact
in
brightness at night may
a
and
se
clo
be a faint star quite
ay.
aw
far
y
bright star ver
t star
For example, the neares
ri,
tau
Cen
to our Sun is Alpha
tant.
dis
*
ars
t-ye
ligh
which is 4.3
tance,
dis
t
tha
at
re
we
Sun
If our
billion
it would appear over 38
our
in
times fainter than
uld be
daytime sky! In fact, it wo
in
night sky, which is the ma
the
in
n
cyo
Pro
as
t
as fain
g)
Do
all
Canis minoris (The Sm
star of the constellation
ion of Orion.
near the great constellat
ary
stars, like our Sun, but bin
Many stars are not single
of
sum
the
Their brightness is
or multiple star systems.
ponent stars.
the brightness of the com
n.
htness in a regular patter
Some stars change brig
sons
rea
ny
stars. There are ma
These are called variable
.
Sun
the
e steadily like
why these stars don’t shin
is measured on a
ess
In astronomy, star brightn
numbers indicate fainter
er
larg
ere
magnitude scale, wh
are very bright objects.
stars and negative values
sky
ects appear in the night
How bright celestial obj
ual
act
ir
magnitude’. The
is termed their ‘apparent
‘absolute magnitude’.
ir
the
d
me
ter
brightness is
insic
calculation of a star’s intr
Absolute magnitude is a
be at
to
e
its apparent magnitud
brightness by adjusting
a standard distance**
at the
magnitude of −26.7, but
Our Sun has an apparent
. This is
4.8
of
e
absolute magnitud
standard distance has an
e in the
ion
Ple
as
wn
-nuku (also kno
nearly as faint as Tupu-a
s).
ter
Sis
en
Sev
e
(th
iki
r in Matar
Pleiades), the faintest sta
ance of ~9.5km trillion.
* One light-year is a dist
d,
ecs (32.6 light-years) is use
pars
** The distance of 10
nd.
eco
arcs
llax
where a parsec is a para
The Sun is 400,000 times
brighter than the Full Moon.
Check out these other resources...
Brightest stars in the night sky: https://en.wikipedia.org/wiki/List_of_brightest_stars
Star charts: http://observe.phy.sfasu.edu/SFAStarCharts/SFAStarChartsPro.pdf
Stardome monthly star charts: https://www.stardome.org.nz/astronomy/star-charts/
RASNZ charts and information: http://www.rasnz.org.nz
Is a planisphere (star
How many stars aren’t
wheel) better than
because
live
using star charts?
you
where
visible
of light pollution? DISCUSSION
POINTS
STARDOME.ORG.NZ
09 624 1246
ACTIVITY
PLANETARIUM
STARDOME OBSERVATORY &
S
S
E
N
T
H
G
STAR BRI
e time to look
stars, take som
e
th
at
up
ze
ch other.
d ga
dimmer than ea
a clear night an
or
on
er
e
ht
id
ig
ts
br
ou
e
e
When you ar
uch the stars ar
and see how m
lly
fu
t
re
ca
em
at th
a moonless nigh
To view the stars:
dark,
u select a nice
M
ake sure yo
e
e
ay from th glar
safe, position aw
et,
re
st
e
th
ighbours,
of lights from ne
, etc.
passing vehicles
eyes
inutes for your
A
llow 5-10 m
is is
Th
.
ss
darkne
to adapt to the
ing
be
r
te
rtant af
especially impo
d
an
s
e light
inside with hous
.
TV
watching
e to
ill need this tim
Y
our eyes w
lit
a
e
av
le
u
e yo
adapt each tim
area at night.
ht
ht, or a white lig
U
se a red lig
e,
d cellophan to
covered with re
aptation.
maintain dark ad
look
ld go outside to
C
hildren shou
n
he
w
ly
ght on
at the stars at ni
ult.
responsible ad
a
by
d
supervise
it’s
if it’s cloudy. If
D
on’t give up
0
-3
20
y
er
ev
eck
very cloudy, ch
ds.
ou
cl
e
th
in
k
ea
minutes for a br
tside
cloudy, stay ou
If it’s just a little
ds to
eaks in the clou
and wait for br
en stars.
reveal the hidd
t, don’t delay
If it’s a clear nigh
s.
oking at the star
or postpone lo
se
or
ely to be w
It’s more than lik
night(s)!
xt
viewing the ne
st
The neahree Sun,
star toa tCentauri,
Proxim faint to
is too ithout
see w lars or
binocu cope.
a teles
THE BRIGH
TEST
STAR IN TH
E
NIGHT SKY
IS
SIRIUS (ALP
H
CANIS MAJO A
RIS),
NEAR ORIO
N.
can see on
e sky.
many stars you
Se
ight Moon in th
e how
ght with the br
ni
a
ith
w
d
re
compa
d and identify
anisphere to fin
pl
a
or
t
ar
ch
g.:
p, a star
Us
ns in the sky, e.
e an ap
hter constellatio
ig
br
d
an
er
s
gg
the bi
• Southern Cros
• Gemini
• Orion
• Scorpius
ster (Matariki).
• Centaurus
Pleiades star clu
e
th
in
e
se
u
yo
y stars can
Ho
rn Cross?
w man
s of the Southe
e brightest star
fiv
e
th
e
se
u
.
Ca
n yo
ir of binoculars
ations using a pa
rv
se
ob
e
es
th
Re
peat
POINTERS
SOUTHERN CROSS
Star name(s)
Alpha (α) Centauri (Rigel Kent; Toliman)
Apparent
brightness
Distance
(light-years)
-0.27
4.3
Beta (β) Centauri (Hadar)
0.6
390  
Alpha (α) Crucis (Acrux)
0.8
320  
Beta (β) Crucis (Mimosa)
1.3
280  
Gamma (γ) Crucis (Gacrux)
1.6
88  
Delta (δ) Crucis
2.8
375  
Epsilon (ε) Crucis
3.6
228  
Star charts are usually reversed,
with black stars and a white sky,
and show brighter stars as larger
symbols and graduated smaller
symbols for fainter stars.
nd it to us.
se
d
an
ity
tiv
ac
ur
yo
of
o
ot
ph
a
Take
ardome.org.nz
st
n@
io
at
uc
ed
it!
e
se
to
e
lov
e’d
W
STARDOME.ORG.NZ
09 624 1246