Getting Started in Astronomy (Northern Hemisphere)(2003).pdf

(838 KB) Pobierz
[
NORTHERN HEMISPHERE VERSION
]
GETTING STARTED IN
ASTRONOMY
INCLUDES A MOON MAP AND STAR CHARTS
AN EASY GUIDE TO
EXPLORING THE
UNIVERSE
FROM THE
EDITORS OF
®
SkyandTelescope.com
®
SkyandTelescope.com
Your First Steps
in Astronomy
Northern Hemisphere Version
way around the sky. They also give you a
view that’s right side up and straight in
front of you, making it easy to see where
you’re pointing. Binoculars are fairly inex-
pensive, widely available, and easy to carry
and store. They’re also versatile; you can
switch from terrestrial to celestial viewing in
an instant.And their performance is surpris-
ingly respectable. Ordinary 7- to 10-power
binoculars improve on the unaided eye
about as much as a good amateur telescope
improves on binoculars — and at a far
lower cost. For astronomy, the larger the
front lenses are, the better. High optical
Read It and Reap
The joy of astronomy comes from finding quality is important too. But any binoculars
already knocking around the back of your
your way around the starry sky and
understanding what you see. A great place closet are enough to launch your amateur-
to start is your local library or bookstore. astronomy career.
Browse the astronomy shelf for beginner’s
Use Maps and Guidebooks
guides that will teach you about the
Moon, planets, and constellations. Check Once you’ve learned your way around the
the magazine rack for
Sky
&
Telescope,
the night sky, binoculars can keep you busy for
years. With good maps and reference books,
hobby’s essential monthly magazine. It
offers practical tips for observers as well as you can identify dozens of the Moon’s
articles on many fascinating astronomical craters, plains, and mountains. Binoculars
will show you the ever-changing positions
topics.
of Jupiter’s moons and the crescent phases
Another great resource is the World
Wide Web. Start at
Sky
&
Telescope’s
site, of Venus. They’ll also reveal most of the 109
SkyandTelescope.com, or you can use any “M objects,” the star clusters, galaxies, and
nebulae cataloged by 18th-century
search utility to look up topics such as
astronomer Charles Messier. Binoculars will
“amateur astronomy” or “stargazing.”
let you split scores of colorful double stars
and allow you to follow the fadings and
Let the Stars Get in Your Eyes
Go out on any clear, dark night and famil- brightenings of numerous variable stars.
iarize yourself with the star patterns over- All this and more is possible — but only if
head, using the constellation maps on the you know where to look and what to look
for. Moreover, the skills you’ll develop using
following pages.
If you live in a brightly lit city or town, maps and guidebooks with binoculars are
find a place where there’s less light pollu- exactly the skills you’ll need to put a tele-
tion (or at least a spot free from the glare scope to good use.
of nearby lights) so you can see more
Seek Out Other Amateurs
stars. The ability to look up and say,
There’s nothing like sharing an interest with
“There’s the North Star!” or “That’s
others. There are hundreds of astronomy
Saturn!” will provide pleasure — and a
clubs worldwide;
Sky
&
Telescope’s
Web site
sense of your place in the cosmos — for
includes a directory of them. Call a club
the rest of your life.
near you to find out when it holds meetings
or all-night observing sessions called “star
Start with Binoculars
parties.” These events offer a wonderful
Binoculars are an ideal “first telescope”
for several reasons. They show you a wide opportunity to try out different telescopes,
learn new skills, and make friends.
field of view, making it easy to find your
D
ID YOU KNOW THAT YOU
can see a galaxy
2
1
⁄
2
million light-years away with your
unaided eye? Or that you can see craters
on the Moon with ordinary binoculars?
These and countless other wonders await
your gaze every clear night. The first step
is simply to look up and ask, “What’s
that?” And when you do, you’ll take the
first step toward a lifetime of cosmic
exploration and enjoyment. What’s the
best way to get started on this exciting
adventure?
2003 Sky Publishing Corp.
Astronomy doesn’t deserve
its reputation as a tough,
expensive hobby to get into.
You just need to begin with
the right advice.
When It’s Time for a Telescope,
Plunge in Deep
Eventually you’ll be ready for your first tele-
scope. This is no time to skimp on quality.
The telescope you want has two essentials.
One is high-quality, “diffraction-limited”
optics. The other is a solid, steady, smooth-
ly working mount. You may also want large
aperture (size), but don’t lose sight of port-
ability and convenience. Remember, the
best telescope for you is the one you’ll
actually use.
Many telescopes have built-in comput-
ers and motors that will point them to any
of thousands of celestial objects at the
push of a few buttons. These are a lot of
fun to use and can help you locate sights
you might otherwise overlook. But it’s still
helpful to know your way around the sky
— especially if your batteries run out!
It’s true that telescopes can cost many
thousands of dollars, but it’s also true that
some good ones can be had for only a few
hundred dollars. Can’t afford the scope
you want? Save up until you can.
Another year of using binoculars while
building a savings account will be time
you’ll never regret.
Relax and Have Fun
Don’t get upset if you can’t find a particu-
lar object or because the view in your tele-
scope is less than perfect. Learn to take
pleasure in whatever your eyes, binoculars,
or telescope can show you. The more you
look, the more you’ll see. Set your own
pace, and revel in the beauty and mystery
of our amazing universe!
®
SkyandTelescope.com
Finding Your Way
Among the Stars
your neck up, is the bright star Vega. It’s
part of the little constellation Lyra.
You’ll notice that east is left of north on
our charts, not to the right as on maps of
the Earth. This is because the charts are
used while looking up, not down.
Northern Hemisphere Version
Here’s how to use our bimonthly
star charts to identify your
evening stars and constellations.
C
AN YOU SPOT THE
B
IG
D
IPPER
?
Orion? The
Pleiades? Your exploration of the universe
begins with learning the stars in your
evening sky. But different constellations are
visible at different times of year and hours
of the night, depending on your latitude
and which way the night side of our planet
is facing.
The accompanying charts will help you
get oriented. They’re designed for sky-
watchers in midnorthern latitudes such
as the United States, southern Canada,
and Europe. Each represents the entire
sky at the dates and times printed on it.
Find a chart appropriate for your date,
and go out within an hour or so of the
time listed.
Looking Deeper
Take the maps out often, and try to learn a
new constellation each night. You are
establishing the landmarks you’ll need for
finding your way when you start using
binoculars or a telescope.
Once you know at least some constella-
tions fairly well, you can start exploring
the sky a lot more deeply with optical aid.
For this you’ll need larger star charts that
show more close-up detail.
The maps here show stars as faint as
magnitude 4.5. This is about as faint as
you can see with the naked eye through
suburban light pollution. Also plotted are
some interesting objects for binoculars or
small telescopes: star clusters, nebulae, and
galaxies. When hunting for these faint
sights you’ll have an easier time if you use
larger charts that show stars to at least as
faint as magnitude 6. (Higher magnitude
numbers mean fainter stars.)
People who get serious about using a
telescope will want even more detailed sky
charts — ones that show stars as faint as
magnitude 8 or so.
Sky Atlas 2000.0
by Wil
Tirion and Roger W. Sinnott is the set
most widely used. The latest edition shows
81,000 stars to magnitude 8.5 and 2,700
galaxies, star clusters, and nebulae.
Clear skies!
Tips for Success
Find a dark viewing site and bring a dim
flashlight to read the map by. It’s best to
use red light, which helps preserve your
night vision.
When you start out, look only for the
brightest stars on the map, those depicted
with the biggest dots. Mentally blank out
the fainter ones if you are in a city or sub-
urb (or in bright moonlight); they will be
invisible or nearly so through the “light pol-
lution.” But wherever you are, remember
that there is a much bigger difference
between bright and faint stars in the sky
than is suggested on the chart.
Remember that the chart is a very
reduced representation of the real sky. To
see how reduced, hold your hand at arm’s
length with your fingers fully spread as
wide as you can. One of these “hand
spans” from thumbtip to little fingertip is
a little less than the length of the Big
Dipper. Compare this with the size of the
Dipper on the charts. You can work your
way around by remembering this rule:
One hand span in the sky is slightly less
than an inch on the chart. Pretty tiny!
The maps are drawn for an observer at
40° north latitude (for example, Denver,
New York, Madrid). If you’re far south of
there, stars in the southern part of the sky
will appear higher than the map shows,
and stars in the north will be lower. If
you’re far north of 40° latitude, the reverse
will be true.
The Moon and planets are not plotted
because they’re always changing position.
Find the line arcing across each chart
labeled “
ECLIPTIC
.” This is the line near
which the Sun, Moon, and planets always
travel. It’s called the ecliptic because it’s
where eclipses can occur.
If you see a bright “star” near the eclip-
tic that’s not on the map, you’ve located a
planet. To figure out which one it is, con-
sult the latest issue of
Sky
&
Telescope
or
visit SkyandTelescope.com and use our
Interactive Sky Chart.
How the Charts Work
The round edge of each chart represents
your horizon, with compass directions
labeled. Turn the map around so the edge
marked with the direction you’re facing
(north, east, or whatever) is right-side up.
The stars above this horizon on the map
will now match the stars you’re facing.
Ignore the rest of the map for now.
The map’s center is overhead (the
zenith). So a star that’s plotted halfway
from the edge to the center can be found
about halfway up the sky. That is, it will be
halfway from horizontal to straight up.
Dot sizes indicate star brightnesses —
the larger the dot, the brighter the star.
Example: Let’s try the July/August chart.
Turn it so the horizon labeled “Facing
West” is right-side up. About halfway from
there to the center is the bright star
Arcturus. Go outside around one of the
dates and times listed, face west, and look
halfway from horizontal to straight up.
There’s Arcturus!
To the right of Arcturus, in the north-
west, is the Big Dipper. Turn the chart so
the “Facing NW” horizon edge is right-
side up. When you hold the chart correct-
ly, the Dipper’s handle stretches toward
the upper left and its bowl is at lower right
— just the way it looks in the northwest-
ern sky. Nearly overhead, as you crane
Greek Letters on Star Maps
The brightest stars in each constellation
are named with lowercase Greek letters. A
constellation’s most brilliant star is often
called Alpha, the first letter in the Greek
alphabet. The letters are used with the
Latin genitive form of the constellation
name, so the Alpha star of Centaurus is
called “Alpha Centauri.”
Here is the lowercase Greek alphabet as
used by astronomers:
α
β
γ
δ
ε
ζ
η
θ
Alpha
Beta
Gamma
Delta
Epsilon
Zeta
Eta
Theta
ι
κ
λ
µ
�½
ξ
ο
π
Iota
Kappa
Lambda
Mu
Nu
Xi
Omicron
Pi
ρ
σ
τ
υ
φ
χ
ψ
ω
Rho
Sigma
Tau
Upsilon
Phi
Chi
Psi
Omega
2003 Sky Publishing Corp.
Evening Stars in
®
Jan/Feb
Every issue of
Sky
&
Telescope
magazine contains a full-color
star chart for the current month.
SkyandTelescope.com
Northern Hemisphere
How to Use This Chart
for latitude 40° N.
When to Use This Chart
Early Jan.
Late Jan.
Early Feb.
Late Feb.
10 p.m.
9 p.m.
8 p.m.
Dusk
*Daylight-saving time
CO
DRA
η
M31
EDA
t
ea
Gr
re
ua
Sq
ROM
α
α
M3 4
γ
AND
α
S
SU
GA
PE
α
β
Pleiades
E
C
L
I
P
T
I
C
Aldebaran
Hyades
α
α
γ
Betelg
TAURUS
ix
ira
M
M
E
O
M4
M4
6
7
α
Siri
us
Fa
CA
NI
S
δ
β
M4
1
α
S
NU
DA
I
ER
ci
MA
JO
R
β
LEPUS
ng
S
η
ε
E
P
U
P
P
α
IS
Fa
ci
ng
S
W
–1
Star magnitudes
0 1 2 3 4
Facing
South
2003 Sky Publishing Corp.
ria
Op ble
en sta
Gl clu r
ob st
e
Ga ular r
la cl
x
us
te
Pl y
r
an
e
Di tar
ffu y n
se eb
ne ula
bu
la
COL
UMB
A
Va
β
S
κ
Rigel
C
R
β
E
T
O
C
M42
U
N
ζ
ε
S
O
ORI
ON
euse
Bellatr
δ
α
AR
IES
α
Zenith
PISCES
F
a
c
i
n
g
We
s
t
US
Algol
E
RS
PE
β
TRIANGULUM
M33
β
F
ac
in
g
N
W
C
Y
G
L
N
A
U
α
C
S
E
De
ne
b
R
ο
T
A
C
δ
µ
AS
S
C
EP
HE
US
IO
α
α
β
PE
IA
γ
D
o
C l u u bl e
ste
r
Facing
Nor
th
CAMELOPARDALIS
α
L it tl e
D ip p e r
Polaris
The chart is also useful in early October at 5
a.m.*, early November at 2 a.m., and early
December at midnight.
Go out within an hour or so of the time listed at left.
Turn the chart around so the edge marked with the
direction you’re facing is right-reading. The stars
above this horizon on the map now match the stars
in front of you. The map’s center is overhead (the
zenith). So a star plotted halfway from the
edge to the center can be found
in the sky about halfway
from horizontal to
straight up.
URSA
R
MINO
β
Thuba
M
82
n
M
81
D
B
α
ip
ig er
p
r
iza r
M lco
A
&
ε
ζ
γ
A
R
S
R O
J
U
A
M
Fa
L
MI EO
NO
R
M44
ci
e
ng
N
E
LEO
β
L
Y
N
X
Sickl
α
ella
Kids
8
Cap
M3
6
M3
GA
RI
7
AU
M3
Facing
East
A
DR
HY
β
s
Ca
α
Regulus
tor
ll
Po
ux
α
CANCER
α
IS
N R
A O
n
C IN
yo
M
oc
Pr
β
G
E
M
IN
I
γ
5
M3
Alp
har
d
α
Evening Stars in
®
Mar/Apr
Every issue of
Sky
&
Telescope
magazine contains a full-color
star chart for the current month.
SkyandTelescope.com
Northern Hemisphere
How to Use This Chart
for latitude 40° N.
When to Use This Chart
Early Mar.
Late Mar.
Early Apr.
Late Apr.
11 p.m.
10 p.m.
10 p.m.*
Dusk
*Daylight-saving time
The chart is also useful in early
December at 5 a.m., early
January at 3 a.m., and
early February at 1
a.m.
Fa
ci
ng
N
E
Go out within an hour or so of the time listed at left.
Turn the chart around so the edge marked with the
direction you’re facing is right-reading. The stars
above this horizon on the map now match the stars
in front of you. The map’s center is overhead (the
zenith). So a star plotted halfway from the edge to
the center can be found in the sky
about halfway from hori-
zontal to straight up.
IOP
EIA
δ
S
l
go
Al
α
P
E
R
S
E
U
β
M
34
Ca
pe
lla
α
IG
s
38
M
Kid
A
β
Ple
iad
es
US
UR
TA
36
M
R
A
N
α
Y
Hy
37
ade
X
U
s
Zenith
Pollux
ζ
E
O
C
T
I
I
P
C
L
E
SEXT
ANS
Pro
cyo
S
O
C
E
R
κ
N
M
U
S
6
M4
HYDRA
δ
M
41
IS R
N O
A J
C A
M
Fa
L
R
V
β
ci
ng
S
E
ANTLIA
XIS
PY
η
ε
P
U
P
P
IS
F
i
ac
ng
E
O
CR
AT
ER
Alphard
7
M4
S
2003 Sky Publishing Corp.
Facing
South
Va
ria
VELA
Op ble
en sta
Gl clu r
ob st
e
Ga ular r
la cl
x
us
te
Pl y
r
an
et
Di ar
ffu y n
se eb
ne ula
bu
la
P
C
α
α
Si
s
riu
O
W
Star magnitudes
–1 0 1 2 3 4
U
S
α
Rige
l
β
O
n
α
M42
L
Re
gu
lus
C
M AN
IN I
α
O S
R
Bete
Virg
Gal o
a
Clu xy
ste
r
lgeu
β
le
R
CE
AN
C
se
Si
ck
M4
4
OR
ION
Bella
ε
trix
γ
δ
α
F
a
c
i
n
g
We
s
t
M
β
GEMINI
α
β
Castor
γ
n
bara
Alde
L
M35
Fa
ci
n
g
N
W
D
Cl oub
us le
te
r
α
CAS
S
CA
ME
LO
γ
PA
R
β
DA
LIS
Facing
Nor
th
CEPHEUS
Polaris
M81
M82
α
µ
SA
UR OR
MIN
α
β
u
Th
ba
n
D
L
Di ittle
pp
er
R
A
C
O
M
92
H
E
R
C
U
M1
3
L
E
S
M
& Aizar
lco
r
CO
BO R O N
A
RE
AL
IS
γ
Di Big
pp
er
M U R
A SA
JO
R
α
Poin
η
ζ
α
ε
BOÖ
TES
CANE
M51
S
V
ENAT
IC I
COMA
BERENICES
ters
β
M9
SERPENS
CAPUT
7
Facin
g
East
M3
α
Arcturu
s
M
L
O
E OR
IN
O
RG
VI
α
Sp
ica

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika:

Zgłoś jeśli naruszono regulamin