S T A R G A Z I N G SERIES
"
*
@
sti ler Y a
1 S* 44*&p\ -
.--, *
60 Small-Scope Tours for Starlit Nights
Sue French
A
Celestial Sampler .
. . .-
. 'I t _ -
Cs
60 Small-Scope Tours for Starlit Nightse,,.
By Sue French . .,,., 'c: ,:..:; 'i .:;+,:' ;L! . * . , 2.;'; :, .; ;y.- .:I,:; ti;.. .r~y
a
.
.
. ...
. :
..' ,
6-
'
I
.. . .
.
. .
.
. . . . .
58 3: Celestial Sampler
...
.
.
Its stars are loosely scattered and show
Y
.
.
.
,:. .
P I.> 7 : :
. . . .
Telescope's 1" field of view
.
be arranged in chains radi
!.
: .
..
\C~>LYWI4
. .
,
.
.
.
.Arn+~&j&$~ t94-ai~m&a&ncw~, +. -r t:;*r::
I
Finderscope's field of view:
wide, nearly matched pair
: ; '%
.
d
'
,
71
r.
4
. ~ . ~ ~ ~ t ~ -%a b :6. ~ ~ + f i ~ ~ ~ j
! j IC, J
--I>.
.$*-.&&ir'..:,
..... ::r
zh..40"'
I
.7"26i\
"
. . E' . 7h001n ,
'
6h40m.'
.COY
Chapter 1: JANUARY FEBRUARY MARCH
can be found near M47; just follow a 9th-magnitude stars northward. about 30 faint stars loosely scatThe center of the group is fixed by one embers, the double star h3983 (a diserschel). The 9.l:magnitude primary de secondary 8" west-northwest. The elf a double, b13f the components are all telescope to split. NGC 2423's lucir "brightest membern)is an 8.6-magouth-southwestborder, but most of hine at magnitude 11or 12. 'th a short focal length can showcase the same field of view at 25x or less. eyepieces will allow you to push the high as 45x and still fit them all in. of these three disparate "star citiesn m a t i n g view.
wandering through Puppis is one of my favorite pastimes. Its exceptionally rich star fields provide fertile hunting grounds for any deepsky observer, with dozens of objects visible through a small scope. One of the constellathnls most magnificent areas is visible to the unaided eye as a hazy patch in a dark velvet sky It contains most of the objects we'll take a lsok at in Phis essq. Let's begin with M46, a singularly stunning star cluster. Even in u x 70 binoculars it appears extremely rich in minute stars:But to be sure you're looking in the right spot, first center your telescope on the 4thmagnitude star Alpha (a) M o ~ and~then sslew 5" due south. My 4.1-inch (105-millim&er)retractor at 17x shows M46 as a r o d , densely packed swmn of faint s m ovZr a hazy ba&mound. Tbe brightest star is
AT THIS TIME OF YEAR,
'
an 8th-magnitude orange star. At low powers NGC 2440 looks like a slightly fainter star, but 87x reveals a northeast-to-southwest oval that is distinctly robin's-egg blue. The planetary is bright and takes magnification well. At 153x I can see a bright spot in the middle, but this is not the central star. With his +inch refractor at about 4oox, California amateur Ron Bhanukitsiri has been able to split this brightening into two distinct knots - a sight usually reserved for larger telescopes. Although too faint to be seen in a small telescope, the nebula's central star has one of the hottest confirmed surface temperatures. It blazes at more than 200,ooo~C,which is 30 times the surface temperature of our Sun. As the lustrous Milky Way plunges through Puppis, it leaves many such wonders in its wake. Be sure to set aside the enchanting hours of a s ~moonless , eve to enjoy them.
hts in Northwestern Pupp ,
into fine powder with sting g h t s of light.
y
)pen cluster 'lanetary nebula
)pen cluster
Look for it just west of
y
1
Mag.
%ize/Sep.
m
Dist. (I-vl
RA
Dec.
6.1
27'
4,500
7 h 41.8"
-14" 49'
11.0
64"
2,900
7h 41.8"
-14" 44'
1,600
7h36.6"
-14' 29'
6.7
19'
2,500
7h37.1"
-13" 52'
{ngulor sizes ore from cotologs or photographs; most objects appear somewhat smaller when a telescope IS used visually.
tive to the star 2 Navis (now known as 2 position he gave was 9" east and 44' sou we say instead that M47 is 9" west and 44'
lished in 1654, both describes and maps th now call M47. Through 14 x 70 binoculars, 20 to 25 st very loose, irregular cluster l/2" across. mixed bright and faint stars in my little picked out among them.
ce~enfalSampler
* 61
Chapter I: JANUARY
Cancer, the Crab, is now well placed for observing with its upside-down Y sandwiched between the brighter stars of Leo,the Lion, and Gemini, the 'Itvins. In Greco-Roman mythology, the goddess Hera sent the Crab to attack the hero Hercules as he battled the muhiheaded Hydra. Hercules promptly crushed this minor distraction underfoot, but Cancer gained a place inhthesky Zor its trouble. For the ancient Greeks the Sun appeared in Cancer on the summer solstice (June =st). This placed the Sun directly overhead at noon at 23.5" north latitude, a line since known as the Tropk of Gancer despite the fact that the Sun now rests near the 'Pam-Gemini border on that date mtju& .. '&is whw eon&e]la-
FEBRUARY
MARCH
veds a rich group of 50 faint to very faint stars in about 25'. A 7.8-magnitude yellow-orange star lies just within the northeastern edge, while the rest range from 9th through 12th magnitude. M67 has an irregular outline that has stirred the imagination of many observers. Admiral Smyth described it as "gathered somewhat in the form of a Phrygian cap; followed by a crescent of stragglers: an image unlikely to leap to mind. Camille Flarnmarion likened it to a sheaf of corn, a more manageable semblance. Stephen James OIMearasees either a rearing king cobra that has swallowed its prey, or a swarm of insects attracted to the golden light of the brightest star. Unleash your imagination while gazing at the suns of M67, and see what impression they leave in your mind.
THE ZODIACAL CONSTELLATION
mary as yellow, while the 6.6
to the nohvgest has a nic
Crabby Delights
ring nearly 1.5" across. 47x, I can count 80 stars m my semirural home in u p nights of very good transparencg; I arranged in many distinctive triangles a V-shaped asterism reminiscent of
I .
I
-
gh0orn'. .
pear orange and white, while the
--
7.. .
.
.'
. .. .
.. . .
8,h30"1
,.
.I
.\'
\
.
.
ghb0'.
..
:.
. field of view:
..
+25'-
-'
0 Telescope's
s a second Messier cluster, M67, often r of its brighter neighbor. It is one of
and all the via lactea quarter of them was not taba
e west of Alpha (a) Cancri. A 2.4-
and the Pleidks
rs the view from the north edge. (If you're
Cancer is &no ~ y @ efirst starry harbtnger across the skygf&&ng aRer Gemini and j
..... ] Star magnitudes
.
3 4 5 6 7
.
Celestial Sampler
..
*
63
.
April May June
Springtime is galaxy time.
I. '
. .
Why not explore some ofthe ,
members ofthegreat Wrgo
May Chasing Treasures Under the Dipper ......76 A 'behold in the Virgo Cluster
':
:* h 45.,
Cluster;about 50 of these .m it
;
............78
Coma Squared ........................... .80
:'Under Virgo's Wing ...................... .82
l.,
galaxies are bight eploggh to
be visible jn a s m d telesc0j-g
,
Markarian's Chain
I
.................
June :
Dazzling Doubles, Glittering Globulars ...86 Polar Nights
Boiites, an8l;eo. ~ d f f W i & 4f
.............................. .............
;ALL% > ' Grabbing the Bear by the Tail '
your sky isn't dark enough to
Spectral Hues of Double Stars .............92
I
hunt galaxies, rve also included more than w pretty 7
,
'Tril
double stars scattered:+
!re;
.
I.,
"
$9 L.
~ ! , j r l - ~ t
.
I
throughout the c o n ~ f e k t i o .q ~ ~ .
of spring. -.a,:,:.:.
...-, . ..-- s -ir;lvT nn?:~?r .,.
e!
.
t>
x , ~ ~ , : ; . ~ ~ ~ : ~ ~ ~ ~ ~
;+:. L.,;,j'f&+ir,! 3xfq3::,)_.: ..'.
Riches Beneath the Big Dipper's Handle
th-magnitude stars 24 and to restore the monarchy in 1660, his that this star shone with unusual b heart of the new king's slain father joy. English cartograph
,4
5
Arcturus
I , .
--
m
To locate our next galaxy, we'll start at the 6.5-magnitude star at the eastern side of our T's crossbar. The face-on spiral galaxy Mi00 lies just 35' east-northeast of this star. Through my 4.1-inch scope at around loox, this galaxy appears slightly oval, about 4' by 3', and is tipped east-southeast to west-southwest. Its halo is fairly uniform and contains a small, round, brighter nucleus. A 6-inch scope can start to show, within the halo, slightly brighter patches that define the galaxy's spiral arms. Photographs of Mloo reveal the beautiful structure that astronomers label a grand-design spiral (one having two principal arms). The T of stars and the galaxies M98, M99, and Mloo give us our toehold in the Virgo Cluster, but don't stop here. Once you've familiarized yourself with the area, use a good atlas to star-hop, or even galaxy-hop, to new sights. For example, from Mloo you can scan 45' east to a 6.7-magnitudestar. From there it is 2.3' north to M85, or 2.g0 south to M86. M86 lies right next to M84, and this pair marks one end of a long, distinctive curve of galaxies lmown as Markarian's Chain (see page 84). Take it a little at a time and eventually you'll master the brighter galaxies of the Virgo Cluster. Then, someday soon, perhaps you'll be the one showing a novice how to navigate them.
The symmetry of arms makes it a showpiece. In
of the Mdky Way runs through the constellations that hug the horizon on May's all-sky chart on page 24. With the plane of our galaxy and its obscuring dust clouds riding so low, we can gaze up into an unobstructed sky and peer far into deep space. O w clearest view is toward the North Galactic Pole in the constellation Coma Berenices, where we just happen to find the nearest large cluster of galaxies. Some 60 million light-years away, the Virgo Galaxy Cluster splays out across tbe borders of Virgo and Coma; its location is indicated on the May all-sky map. Its 2,000 member galaxies form the core of the Local Supercluster, with our own Local Group as m outlying member. The tremendous mass of the V i p Cluster acts on the galaxy groups around it, slowing the recession they would otherwise have as part of the uni-
galaxies can be seen in M100's vicinity. But NGC 4312, the needlelike object 'Is0to the south-southeast, is beyond the reach of a
THE HAZY BAND
About 50 Virgo Clus objects, are bright eno escope. With such an the old adage: Well hold in the Virgo Cluster to start and then carry our
is surrounded by a very faint, oval halo.
for 61/20to find 6 Comae. It is the bri
'"i
littlefainter thon the 0th. ers. The star 6 Comoe Berenices lies just outside the left edge of this close-up view. Below: M 9 9 completes a triangle with stars of 6th and 9th magnitude . that shine brightly in the %me telescopic field:This . ~ l a x y ' miniature s pinwheel, so striking on photographs, requires a large scope to be detected
magnitudes 6.4 to 6.9. This group of stars will be our home go Cluster. A finder will eas~lyencomp
Constellation
RA
ons with other Virgo Cluster ier objects: M33 and a high velocity of its
-
l Z h 13.8"
. +14" 54'
Coma Berenices
lZh18.8"
+14O 25'
Coma Berenices
lZh22.9"'
+15O 49'
Coma Berenices
l Z h 25.4m l Z h 26.2"'
:
.
I
Easy Galaxies in the Virgo Cluster
' +la0 ll', Coma Berenices - -."..-+I+?'?@!-. Virgo ; r: Virgo
-- &
Cluster as a whole'
'"
patchy core and an off-cen
.
Since the Virgo Cluster as a whole about 1,100km/sec, M98 must be tion at a rate of 1,225 kmlsec with respe of its cluster. The immense mass of the gravitation* accelerates many of its me individual velocities, so that the light fro
. - I
+I$
Pans more than 10" of sky (see inset good starting place is the T-shaped
0
right. The face-on spiral galaxy M99
M98
1,
6
0:
.
'.
. :
VIRGO
'
.
.: .
I
1
.
I
. .
I
COMA BERENICES
.
.
I.
. ,
*'
,
'a
..
p'
-
LtU
I
of Leo's tail star, Denebola.
Celestial Sampler
* 79
h-2:
C O M A BERENICES (Berenice's Hair) flows high across the evening skies of spring for observers at rnidnorthem latitudes. This area is spangled with faint stars when seen under a very dark sky. But only three of these stars are bright enough to make our all-sky map on page 24, where they look like a rotated L just above Virgo. Filling in the blank comer of Coma with the galaxy M85 gives us a square 10" on each side, about as wide as your fist at arm's length. In and near this celestial square, deep-sky sights abound. The constellation Coma Berenices is named for a real person, Queen Berenice 11, who lived in the 3rd century BC and was the wife of Ptolemy m, king of Egypt. Shortly after their marriage, Ptolemy went off to war in response to diplomatic intrigues that included the murder of his sister (also named Berenice). Out of fear for her husband, her king, and (no doubt) her position, Queen Berenice offered her royal tresses to the gods as ransom to secure Ptolemyls safety. When he returned victorious, Berenice made good her vow. Her amber locks were shorn and placed in the temple of Aphrodite, but they vanished shortly thereafter. The royal couple's outrage was quelled by the palace astronomer, Conon of Sarnos. Conon wisely claimed that the gods were so pleased with Berenice's lustrous gift that they placed it in the sky for all to see, now
, amazing sliver of light -the almost perfectly edge-on spiral galaxy NGC 4565 - is a fairly easy catch for any small telescope under dark skies. But the tiny smudge 4 4 O toward lower right, the galaxy NGC 4562, is a tough challenge .visually for 12-inch telescopes.
APRIL
MAY
JUDE
galaxy M85. If your sky is dark enough, you can try to spot nearby 4.7-magnitude 11Comae with the unaided eye (see the finder chart below). It looks yellow-orange through the eyepiece, and you'll find M85 onlv 1.2' J (one l o ~ - ~ o wkeld) & to thk east-northeast. M85 is the northernmost Messier galaxy in the Virgo Galaxy Cluster and one of the brightest. It is easily visible in my 14 x 70 binoculars as a small, oval patch of light. My little refractor at 87x shows a 2' tapered oval that grows smoothly brighter toward the center. A very faint star can be seen on the northern edge, and a 10th-magnitude star lies close to the southeast. In dark skies it's possible to glunpse the much fainter galaxy NGC 4394 east of M85 - their centers are separated by a mere 7.5'. It appears as a small oval with a bright, stellar nucleus.
photographic image, taken with a Celestron My pencil drawing (facingpage), made at 12 fractor, shows a much wider field. Both views
shining as a delicate tracery of glitterin me] who scanned the vast heaven's li Who watched the risings and settings o That same Conon noticed me, Berenice'q In my celestial abode.*
We'll start our sky tour at the star, which is sometimes called pictured at the wrong end of the Qu her jeweled crown. The globular northeast of this pale topaz gem. lar through a small finder, but 14 x 70 a moderately bright, round, fuzzy pat toward the center. With my 4.1-inch fractor M53 begins to look grainy at see a few elusive pinpricks of light o If M53 seems easy, try for the v 5053 just 1' to the east-southeast. OJMeara,who has glimpsed this in delightfully describes NGC 5053 ions: The Messier Objects as "the d more brilliant neighbor." Now let's move to the diagon the Coma square marked by tered over a region 5" across, northern edge, is the nearby open c the Coma Star Cluster, or Melotte ill grouping is so large, a regular telesc here; binoculars or a finderscope 8 x 40 binoculars I can count a doze twice as many fainter ones. The clust very wide, bright double star 17 Comae
*From poem 66 of the Roman lyrfc poet Cdunu~, century BC. It & fuII of astronomkal allusions.
but some observers see the n star as blue-green. 5 (Caldwell 38) lies 1.7' east of It is one of the most impreses in the Revised IZat Galaxy CatKarachentsev and colleagues, h lists thousands of highly edge-on spirals. My little reshows NGC 4565 about 7' thin with a small, brighter e center. Switching to 87% some mottling across the core, the dark lane that m s along
Deep-Sky Riches of Coma Berenices
..
'viJw**-**w Mag. .-_R-.-.
I M53
Dist. (I-y)
RA
Dec.
12'
60,000
13h12.9'
+18O 10'
1 3 16.5' ~
+17' 42'
Globular cluster
7.6
NGC 5053
Globular cluster
9.5
8'
54,000
Me1111
Open cluster
1.8
5"
290
12h25'
17 Corn
Double star
5.2, 6.6
145"
270
l Z h 28.9"' +25"55'
NGC 4565
Galaxy
9.6
16'x 3'
32 million
1 2 36.3' ~
+25O 59'
NGC 4559
Galaxy
10.0
l l ' x 5'
32 million
12h36.0'
+27O 58'
35 Com
Double star
5.0,9.8
29"
320
12h53.3'
+21° 15'
/
M64
Galaxy
8.5
g'x 5'
19 million
12h56.7'
+21° 41'
1
M85
Galaxy
9.1
7'x 5'
60 million
1 2 25.4' ~
+18' 11'
I
NGC 4394
Galaxy
10.9
3'
60 million
12h25.9'
+18"13'
.
nice galaxy can be seen '2 GC 4565. NGC 4559 (Caldwell elongated, but it appears a litand fatter than its neighbor to Two faint stars lie on either galaxy's southeastern end. o-thirds of the way from 17 pha we find the 4.9-magnistar 35 Comae. It is easy to rece brightest star in the area, a 9.8-magnitude companion to that is well separated at 17x. 35 Comae to find M64, the axy, lo to the east-northBlack Eye gets its name from the dust lane that looks so stuntographs. Observers have been this feature in telescopes In my 4.1-inch rehctor appears about 6' by 3' move to the southwestern Coma's square, marked by the
Size/Sep.
+26.1°
n the three main stars of Coma is chart includes fainter stars to mag help in locating the objects in this nderscopes have a field as wide as rcle at top right, which encloses the uster Melotte ill.
Celestial Sampler
Chapter 2: APRTL
1 UnderTSi.oPsWing z
.
.&
oins the scene in the ce. This one is disb w t core. I€you
magnification it looks about 5' by 2' aligned northt to south-southwest. M90 shows a faint halo, a brighter oval core, and a small, bright nucleus. Within this galaxy triangle we can find yet another Messier object. M89 is the dimmest and smallest member of the quartet as viewed through my little scope. This elliptical galaxy is round with a fairly bright, very tiny nucleus. It fades outward hom the center. Many other galaxies ornament the wings of Virgo with their softly glowing stardust. They abound in ess that it's easy to become lost among od star chart (see the Resources section on help you find your way around this galaxy-filled region.
with a distinct core and a A Double Star and 11Galaxies in Virgo
ing to Gharles Messier's with 14 x 70 binomlare.
a m , Epsilon (E) Vir-. To b e e , select an eyepiece a power of about 50x and place
long%talog we'll ~demi-
Size/Sep
RA
7.1,g.l
29"
l Z h 55.5"
10.3
8 . 7 ' ~1.6'
l Z h52.9"
10.6
4 . 4 ' ~2.5'
l Z h52.3"
8.8 11.3
7 . 2 ' ~6.2' 2 . 9 ' ~2.3'
1Zh43.7" 12h43.5"
9.6
5.1' x 3.4'
l Z h42.0"
11.2
2.5' x 1.7'
l Z h42.8"
9.7
5 . 4 ' ~4.4'
l Z h37.7"
8.6
7.2' x 6.8'
12h30.8"
11.5
1 . 7 ' ~1.4'
l Z h 30.3"
9.5
9.5' x 4.7'
12h36.8"
9.8
5.0' x 4.6'
12h35.7"
dog.
able to detect hints of
Double star NGC 4762
Barred spiral
escope ~trixat 1
1.6"
689. ~sists
litude :s of white
to enhe ble. ~ah-
~
galaxy M90 is a bit dimmer d more elongated. At the same
+12" 33'
The golax~esore all members of the V~rgoCluster, wh~chlies about 60 m ~ l l ~ o11ght.years n from our own M~lky 8 Way galaxy. Thev usuallv aooear smoller than the cotaloa slzes l~sted
; l/jO
1rs.
right :tor 2 :d lded
-*..
..
.
pan n
VIRGO
Top left: This attractive galaxy duo, NGC 4762 (left) and NGC 4754, are spaced just '/so apart on the sky (one-third the full Moon's width), so they can be viewed simultaneously in a telescope. Note that five stars in this photograph also appear on the facing finder chart. Top right: The two brightest galaxies in this view are
field. Like all photographs in this article, this view is oriented with celestial north
Mp a d welt toward the right. Bottom right: Spiral galaxy M9O lies l14O northwest
& ~ k seen in a small scope.
u&
Celestial Sampler
Celestial Sampkr
* 83
Chapter 2: APRTL MAY JUNE
:s, and the nLame stu.ck. for the smaJl refractor. NGC ped almost north-s out1I, and it nucleus. NcSC 4438 is 1:arger1 and t i p y d more to the northht core hes at its he:art. The lothe apparent size of the galaxies and f i t stellar nucleus to NGC 4438. with the Chandra X-ray Obser, ~ t $&ate that this galaxy pair underwent a hghv n about 100 million years before our cur-
The reality of Markarian's Chain as a true physical system is still debatable, but that surely won't keep skygazers from enjoying this wonderfully rich area of the sky.
, ,
Galax) M84 NGC 4387
ws a brightish core within a faint M o . splays a stellar nucleus within a s m d , nstellation border from Virgo into ces, we next come to NGC 4473. Avery e q ch, this galaxy is an east-west oval
RA
9.1
l Z h 25.1"'
12.1
l Z h 25.7m
NGC 4388
11.0
l Z h 25.8"'
NGC 4402
11.7
l Z h 26.1"'
8.9
l Z h 26.2"'
NGC 4413
12.3
l Z h 26.5"'
NGC 4425
11.8
l Z h 27.2m
NGC 4435
10.8
l Z h 27.7"'
NGC 4438
10.2
l Z h 27.8m
NGC 4458
12.1
l Z h29.0m
NGC 4461
11.2
l Z h 29.1"'
NGC 4473
10.2
l Z h 29.8"
NGC 4477
10.4
12h30.0"
NGC 4479
1;
l Z h 30.3"
M86 i
Mag.
'
:lo-inch, and a stellar nu-
with. it b t h NGC 4477 and M84 in
d of the lon opposite art of their :careful ma NGC 4479 UUlU w r
113 is the
the edge. ~ uthis t is a faint galh e edge o'i ;
3ok for a
ar 1.6'to : south of
,d looks
XI
The Eyes
1'n ,.,..,
isier. star.just 1,
welU
c 4438. e called copel&
wonderJ rt, wb* h fancd
celestial Sampler
* 85
Chapter 2: APRIL
MAY
m
1y close neighbors. If the distances are correct, each would be about a 2th-magnitude object in the other's sky.
~ a z z l i -Doubles, g Glittering Glob of the constellation Serpens (Serpens Caput)winds its way across the early-summer skies between Ophiuchus (aplycalled the Serpent Bear- . er) and Bootes, the Herdsman. Hidden among the stars of the Serpent is one of the finest - but often overlooked - globular clusters in our sky. Let's begin our tour with this isolated object. From there we'll hop along a bridge of double stars to a close pair of globulars in nearby Ophiuchw. ~5 is the brightest globular cluster north of the celestial equator. It is located 7.7" southwest of Serpenslsbrightest star, Alpha (a)Serpentis. At magnitude 5.8, it is easily visible in a 2.4-inch (60-mjllimeter)telescope as a small, round glow with a fainter, granular halo. A 5th-magnitude yellow star, 5 Serpentis, lies just 0.3" to its south-southeast in the same field of view. A +inch telescope at 150x resolves m y stars laced around the cluster's fringes. The core
ectively Our jump to the , M ~ Ztakes us about t-years. M12 is located 7.7" east is visible through binoculars r as a tiny patch of fuzz.A 4at hq& powers can resolve e stars in the outer halo, while a mottled patch of mist. scope can reveal several
THE WESTERN HALF
ular clusters known. first spotted in 1702 tronomer Gott£ried
its companion because it t of the orange 4.8-magni-
uchi. If you have trouble p Ml2, look for M ~ first o and om there. The twosome can the nucleus. It may be a wo& the hunt. V42 pulses in
nter. Through a +inch
while at minimum it may fade hom
7th-magnitude primary with an 8th ary 6" to the north. It takes around ably split the two. About 5" east of 21985 we find a ble, near the naked-eye stars Delta (
t is the double star 5 Serpentis. The at the Beart of Dp&hrcbus. In tbls image by Akira
Celestial Sampler
* 87
Chapter 2: APRIL
composed of ten 9th- through ~th-imgtdtudestars 1.9" south-southwest of Epsilon (a) time Ws.Like its larger cousin, the Mini-Coathangerresembles an old-fashioned coathanger with a straight wooden bar and metal hook. Seven stars make up the bar, which is about d long.
I'"
.
I . .
.
_
arthe
The sad and solemn night Hath yet her multitude of cheerful fires; The g M o w host of light Walk the dark hemisphere till she retires. . And thou dost see them rise, Star of the Polel and thou dost see them set. Alone, in thy cold skies, Thou keep9 thy old unmoving station yet.
-
Observationally, Polaris has more to power th-
..
- WILLIAM CULLEN BRYANT Hymn to the North Star
at 2nd magnitude, the North Star is the most famous in the sky. Polaris stands essentially still above your landscape all night and all year (assumingyou're in the Northern Hemisphere),holding its station while all others revolve around it. Polaris marks not only true north (to better than 3/40) but also your latitude on Earth - which nearly equals Polaris's altitude above your horizon.
rough treatment, ho ed on its southern side. may has a 9th-magnitude
DIM THOUGH IT MAY BE
I
power split if the stars were more ence of 7 magnitudes (a difference
by the brighter star's glare. Try a m 80x to bring it out. Polaris itself is urements show that their colors are Polaris enjoys its special position axis happens to point toward it. In stands almost dir world turns, the geographic po that face the same direction all that seems to stand still. Yet Polaris moving cynosure described by poet planet misses it sligh*' the true no
The circle will shrink to j coming century. Why?The
orientation of the EarthJsaxis large circle that takes some 26,oo So when will Polaris be closest
the 'enion lond. me dent. le pr lero~ Is0 r low diff e mes I were at lea . Thc mea
1
.None is a m e
I
art and have hues
Zarth it he aces
ly one ie un. our )le is laris ar, rels h
RA 2h 31.8"
+89" 16'
2h 31.8"
+8g0 16'
180
17h32.2"
+86O 35'
155
17h30.8"
+86'5V
350
16h46.0"
+82" 02'
480
15h20.7"
+71° 50'
125
14h50.7"
+74" 09'
4
1 the
MINOR
t
asterism discov-
~ n d space zard
Dist. (I-y)
F5 - 8 I b
1.9-2.1
Star magnitudes
ecause
of its sideways motion with respect Taking all this into account, com
Spectral type Color index
Mag.
:imilr
111it n the n the stars ky in a 11ete. lcstial ;ravita,ddm ,ur the a tiny due to ith re-
m
MAY
5
a (seepage 126).It is "
6
..
7 8 91011
Chepter 2: APRn that's grabbing for the Bear's tail contains double stars Kappa (14and Iota (1) Bootis.
MAY
JUNE
growing brighter toward the long axis. 'Itvo faint stars bracket the galaxy's northwestern end. Messier object lightful sight for the finale of our tour.
I Grabbing the Bear 1: on page 25, you'll see the kiteshaped figure of Bootes, the Herdsman, high in the south. His upraised arm reaches out to grab the tail of. Ursa Major, the Great Bear - or perhaps Bootes has just let her go, and we see the Bear with her tail stretched long from her struggle to get away Let's join Bootes in taking the Bear by the tail and see what riches this area of the sky has to offer. We'll start with the star at the bend of the Bear's tail. Mizar, or Zeta (6)Ursae Majoris, is surely the sky's most famous naked-eye double. Anyone with reasonably good eyesight should be able to spot 4th-magnitude Alcor close by to the east-northeast. Mizar and Alcor easily fit together in a telescope's low-power field, along with an 8th-magnitude star that makes a squat isosceles triangle with them. In 1722 an eccentric German professor, Johann Liebknecht, mistook this faint star for a new planet and named it Sidus Ludoviciana ("Ludwig's Starn)in honor of his king. a Although Mizar and Alcor share a similar distance and motion across the sky, they probably do not form an orbiting pair. Instead, it seems more likely that they are slowly separating members of a star cluster known as Collinder 285, the Ursa Major moving cluster. The central five stars of the Big Dipper all belong to this widely spread group. Mizar, however, is a true binary whose nature is revealed at 40x through a small telescope. The 2nd-magnitude primary has a 4th-magnitude secondary 14" to the south-southeast. Both components are white.
servers see the sec6ndarg as bluish. common for stargazers to perceive tush when it lies near a brighter white, orange star. Whzt color do you see? mponents have a greater color differ- 4.8-magnitude prhmq has a 7.4-mag- :ondary 40" to the northeast, easily w power. Their s p e d classes are A5 espectively;implying colors of white
O N THE STAR CHART
.
"Right at the crook of the Big Dipper's handle
NGC 5866 appears as an edge-on galaxy in pho narrow dust lane running through the middle. Le west-southwest is an 8th-magnitude star (at far
are Mizar and Alcor, which have served as a test of keen eyesight for centuries. They're separated by 11.8', or slightly less than '/so. But almost any telescope reveals that Mizar itself is double. Taken with a Meade 16-inch reflector, the close-up includes the one-time planet suspect dubbed Sidus Ludoviciana.
Mizar was the first binary star discovere photographed, and the first star found tional companion revealed in details of Mizar system have un A fascinating account mizar/article.htm. Our next target is the galaxy MlOl. called the Pinwheel Galaxy, a name it ingly) with two other Messier objects: lum and M99 in Coma Berenices. Thi
nebulous stars comto him, M. Messier was conto an error in the sky chart." uld seem to lay the existence of
Springtime Sights Between Bootes and the Bear
26 million
Double star I G C 5866
NGC 5866 as the e for M102 - if it was
finder, you can follow the line of four magnitude stars that starts east of Miz east-southeast. Each of these methods
alaxy
4.8.7.4 9.9
DRACO
.
38 million
.
www.seds.org/messier/m/
I I
magnification, the core itself appe Long-exposure photography transforms M101, a large hazy patch in small telescopes, into one of the most beautiful of all spiral galaxies. The field here is nearly lo across, with north up.
%lestiaZSampler
'
ootes can be seen to its
k---'gated northwest to southeast),
/
/
CANES'
0 M51.
C k a f l ~1: APRIL
June
are wonderful targets for small telescopes, even in less-than-ideal skies. While getting essax I encountered a stubborn s that offered but one observing Moon, with M y skies at eit. Yet the stars were loveb for I was
a -
. 5%
I
Sen.
F1835
5.0,6.1
6.2
1940. 14h23.4" y o 8 0 27'
AOV
FOV + R V
0.0
+0.4
Boo
4.9, 5.8
5.6"
109"
1 4 40.7" ~ +16O 25'
B9p
A6V
0.0
+O.2
Boo
4.8, 7.0
6.4"
315'
14h51.4" t19.06'
G8V
K4V
+0.7
+1.2
~~
6.5,8.4
4.4"
156"
14h16.5" +20° 07'
F8V
-
+0.5
+0.8
I
2.6.4.8
2.9"
346"
1 4 45.0" ~ +27"04'
KOII-111
A2V
t1.0
+O.2
p2 Boo 4.3, 7.1
109"
,171'
15h24.5" r37' 23'
FOV
GlV
~ 0 . 3 3i.6
5.0,5.9
6.1"
,305"
15h39.4"' +36' 38'
B7V
B9V
-0.1
-0.1
5.6,6.5
7.1"
237'
16h14.7" +33'52'
GOV
G1V
+0.6
+0.6
5,4,5.6
361"
164"
16h22.4" +33'48'
M2III
K5III
t1.6
+1.5
5
DOUBLE STARS
:Boo ,'L
I7
I
Mag.
t
*-
P.A. B
RA
I k.
Soectral
'
I ?
:
citingshades of blue-w
CrB
L
Color perception is a complicated issue involving physiology, psychology, and observing conditions. It's white and yellow-white. he.& little wonder that skygazers report different colors for of a pure white, but contrast wj the same stars. But I had a great advantage when I surveyed the stars described here with my 4.1-inch refractor. Since I had picked the stars, I h e w ~ o n e nhas t been nee& what colors to expect. I also find that first impressions are often the best. After staring at a subtly colored star for a while, my eyes become has been loggeed s W Y less sensitive to the'color. I started by looking up the spectral types of my tarat 87x, they appear orange s gets in the SIMBAD astronomical database. The first Next we'll visit E1825,visible im letter of a star's spectral type roughly correlates with of Arcturus. Its primary has be= its surface temperature. From hottest to coolest the pale blue, yellow, or white, and & main types are 0,B, A, F, G, K, and M,and their cola bluish, white, or orange. At m ors trend h-om blue-white through white, yellow, orstar as white. I couldn't @a ange, and f i n e red-orange. Most spectral types for the secondary, but end in the Roman numeral V, referring to the lucates a yellow star. AM minosity class of main-sequence stars, like our Sun, that are fusing hydrogen in their cores. The Roman numerals 11 and III denote aged giant stars, and a type ending with the small letter p mistakenly means the spectrum is p e d a r . Epsilon (e) Boo, or Izar, is dd Next, I checked their color indices in the European our doubles, and it has justly e w Space Agency's ~ i p p h o and s q c h o Catalogues. The colcherrima (Latin for "most beaut or index is the difference between a star's apparent generally seen in shades of yellmagnitudes at two wavelengths. For blue and yellow~ndaryhas been called m a green light, the values run from about -0.4 for specmost commonly blue, g trd type 0 to +1.7 for type M,giving me an two - but occasion& independent clue as to the hue. In most cases purple1 Among the s the two indicators agreed. this was the most dil The doubles we'll visit are in the constellations mairily because of i t s Bo6tes and Corona Borealis, high in the south on . atmospheric tui-t the all-sky chart on page 25. Our first will overlapping blobs of om@ Izar is one of my favorite dod - be El835 in the far-southemreaches of pleasing views at 87x when the L Bootes. Easily swept up in a finderscope, it is the northernmost of a lit tle arc of three 5th- and 6th-mad-- ------ - - --tude stars lying about 11"southvof --, p.l involve tints of blue, pd V A r m s . Observers have described the primam star as bluish, . . .:. . greenish, white, or pale yellow, and ondary as various shades of blue, white, ---r+&r even lilac. To me they simply appeared it into two very close peY
he star colors shown in this article's small circular plots are those expected from the spectral types ond color indices listec ere. Mnst nf the r i r c l "re ~ ~ 20" nrrncc. thncr fnr 1 6 Rnn nnrl v TrR nrn murh wid..
1
--
,
bst 90'
Primary
1
7
west 270"
C
------>
8
-
i
1 I
r CrB
L
.
~
i I
,
-
WIVE
Double Stars to Test Your Color Sense Object
indculars or a very wide fidd teleare good targets for a n-mowinstrument. ard 110is a 10'dark blotch 1" due )f Herschel VI 50 and 3/40 due east r Scuti. It's near an east-west pair nagnitude stars; the western of s yellowish, and the most conspickart of the nebula starts just to its b B110 widens as it reaches north, $its borders grow less distinct. hard 113 is a similar-size but more ar dark nebula centered about l/zO ast of Bllo. The two are separated Bill
h's os& dofa result,
!
: the
nd B106 a little west-southwest of etailed map of the rich region around use at the telescope with a red flashlight. m 4th-magnitude Beta Scuti, the top cutum's narrow diamond shape on the Dtion chart on page 28. From there you 5s the glowing patch of M I 1 about 2" Iutheast. Using the map: North is up and lft. To find which way is north in your eyeiw, nudge your telescope slightly in the dik ~ o l a r i s new ; sky enters the view from edge. Turn the map around to get propd. If you're using a right-angle star di'11 probably see a mirror image, which h correct-image maps. In this case rementally flip the star patternseastke out the diagonal and view straight see a correct (but upside-down) image.
(P)
vlae,
hwest [litand
tor colul y star of ight giant
jgl is de!ow-whit~ it comes to lor ind@ &ective to intensi-
1
I
-
Celestial Sam
BEHIND THE TAIL of
Aquila, the Eagle, a bright patch of Mdky Way punctuates this otherwise hazy band. In his 1927 Photographic Atla of Selected Regions of the Milky Way, Edward Emerson Barnard devoted a section entitled "The Great Star Cloud in Scutumnto this island of distant suns. He began, "This, the gem of the Milky Way, is the finest of the star clouds. It is interesting h-om many points of view. The main body is apparently made up of extremely minute stars. The great hammer-like head, however, looms up to the west with much coarser stars, as if it were much nearer to us." Here we see the Sagittarius Arm of our Milky Way gdaxy as it curves toward us. Countless stars dong our line of sight create a dense concentration that is a wonder to behold in binoculars. The Scutum Star Cloud is bordered by the Great Rift,a dark dust lane that plunges from Cygnus to Scutum before broadening and turning west through Serpens Cauda toward
.I
Star magnitudes
.... I
4 5 6 7 E
m a l l finderscope can easily encompass4 &a-Blrwssed In this essay (those whose While exploring this reQ w t o l a d c in on R Scuti, the variable star lying only about lo northwest of M l l (see page 121). rimes are in yellow).
,-
Cekstial Sampler
* 123
Chapter 3: JULY AUGUST SEPTEMBER w). A small tele-
group (scattered lta2),making this ,m Delta, we come lhanges can be folme is an eclipsing ~sethat they are disgravitation and rap-
1 Lyre Lessons of our all-sky map on page 28 you'll find Vega - the fifth-brightest star in the night sky and the brightest star in the constellation Lym, the Lyre. According to one myth, the harplike lyre belonged to Orpheus, who charmed every living creature with its music. When his young wife, Eurydice, died, Orpheus went into Hades (the underworld) to seek her return. With the beautv of his music, he convinced Pluto, the king of the unierworld, to let her go. Orpheus was warned not to look back at his bride until they had both reached the light of the upper world. When Orpheus stepped into the daylight he eagerly looked back, but it was too soon. Eurydice was still within the cavern, and as she vanished into the darlmess he heard just a faint "Farewell." Thereafter Orpheus wandered heartbroken, and when he died the gods placed his lyre among the stars. Lyra is the site of many deepsky treasures suitable for a small scope, among them one of the most renowned multiple stars in the sky - Epsilon (e) Lyme, the DoubleDouble. Look for a 4th-magnitude star 1.7" east-northeast of Vega. Binoculars or; finder will reveal that this star is really a double. In fact, under good viewing conditions 1 can just split this pair with the unaided eye. Each of these stars is itself a double. Through a 3.6-
AT THE CENTER
,
rich field of stars. It shows considerable brightening toward the center, and a 10th-magnitude star can be seen outside the western edge. When the air is clear a 6-inch scope at 2oox will partly resolve this globular. As you wander amid the sights of Lyra on late summer nights, let your imagination draw you into what John Milton described in II Penseroso as the haunting melody that "drew iron tears down Pluto's cheek and made Hell grant what love did seek."
The Ring Nebula (M57) in L y r ~pears as a sma doughnut of light through most small telescope exposure photograph like this one from Akira Fu true colors. The Ring is a planetary nebula, an cf ing much of its mass into surrounding space.
) both star. inch ( ~ m d l i m e t e rrefractor, ly split at 94x1an them. The north star with a 6.1-magnitude companion a v the north. The southern star (9) is a littl more closely mat1 ging a 5.4-magnit D
&&ra,thW&,
directly overhecr~~ ~ tsunset. e r I t lies just west of Cygnus; the Swan. Lyra may apbackdrop to zero-magnitude Vega but within its boundaries lie several beautiEpsilon (E) Lyroe, the famous "Double-Double." With low power you should be turn out to be double stars themselves.
at magnitude 5.6. can be seen throt ported binocdm part of the sparse
.
.*'.~-,'~
L'
.
. -
.+
Stephenson 1
-~
6.
1
i
-
On this chart north is up and east is left. The circles show fields of view for a typical finderscope or a small telescope with a low-power eyepiece. To find north through your eyepiece, nudge your telescope toward Polaris; new sky enters the view from the north edge. (If you're using a right-angle star diagonal i t probably gives o mirror image. Take i t out to see an image matching the map.)
Cekstial Sampler
* 125
Chapter 3: JULY AUGUST SEPTEMBER
American Association of Variable Star Ob-
m, who suggested that it be used to calibrate visuUar photometers in the summer the way the
les were used in winter. His name has stuck to ~ ~ s tever e r since. led by ina zer -r wooden bar and a metal hook. Six stars firm rst-west bar; the remaining four make the hook. ! need to use a very low-power eyepiece, or perfit 1h e 1.4'' long. e coathanger's hook contains a pretty quadruple 3521 (Struve 2521). The 6th-magni-
I Emloring:the Den L
u
~
in the late-summer sky flies Cygnus, the Swan. You can find it near the center of our evening all-sky chart on page 28. (Discoverwhat lies within the Swan starting on page 130.) Plotted there just south of Cygnus's head and neck is a small, dim, barely noticeable constellation: Vulpecula, the Little Fox. Only two of its stars barely made it onto the all-sky map (which shows stars as faint as magnitude 4.5). But this sly fox guards some famous telescopic treasures. Vulpecula is one of nearly a dozen small constellations invented by the 17th-centuryPolish astronomer Johannes Hevelius; seven are still in use today. Hevelius originally named it Vulpecula cum Ansere (Fox with Goose) and drew on his star map a fox carrying a goose in its mouth. Since the goose is gone now, one can't help but wonder if the fox finally ate it. Maybe this is why Cygnus has taken flight. Let's begin this small-scope observing project at a bright point that's easy to find: ~lbireo,which marks CygnusJshead. Albireo is the brightest star near the middle of the Summer Triangle of brilliant Vega, Deneb, and Altaiq you should have no trouble spotting it without using any optical aid. Albireo is one of the most beautiful telescopic double stars. A small instrument at very low power easily resolves it into a pair. The 3rd-magnitude bright component is golden yellow; the 5th-magnitude companiorI star appears clear blue-white. Their color contrast is very striking to most people, but a few have trouble seeing colors in stars. Low magnification helps; color? contrasts look most vivid when stars are seen close together. It may also help to put the stars slightly out of focus. The eye is not very sensitive to color in tiny,
HIGH OVERHEAD
scope shows a handful of stars scattered over an elongated hazy background. A 4-inch reveals a few dozen s p i i e d across an irregular, mottled glow about l/zO across. Stars at the limits of vision seem to wink in and out of view, aiving the cluster a look of fraaile beautv. " Althougl ip; :cula revreds Iittle to tlhe unaided eye, the objects lin makre a fox 1:lunt well. worthwhile. CvnnusJs h nelbed US 7with1his ImonthJs deer>-skv . " quarry. Turn to the next essay, and I'll show you where the Swan's tail leads us. w
The Dumbbell or Apple Core Nebula (M27)is ble planetary nebula in the sky. I made the p 4.1-inch refractor at 127x.
brilliant points, so spreading out the li oathangerJsstatus as a cluster put tc when data from the Hipparcos satellovided a sufficiently accurate clue h star's distance (Sky & ~ l e s c o p e : q 1998, page 65). r next target is the planetary nebula bo known as the Dumbbell or Apple Nebula. It appears as a tiny glow in finderscope, noticeably unstarlike.
our deepsky prey carefully. Use right, and make sure you h o w telescope's eyepiece. size and orientation of this, see the sections "Using a Star
4
bireo. This is Alpha (a) Vulpeculae, magnitude 4.4. It has no official c o r n his classic book Star Names, Their published in 1899), R. H. Allen me tionaries that define the star in Vulpecula. Alph&*B be in the right place, for map it marks the fox's m goose. ~hrougha telescc that Anser has an orang4 ange companion, 8 Vdp its north-northeast. Draw a line from Alb' and continue it onward f& times that distance. You
4
name, bl Meaning wo old ( Anser as :culae w
I
, constellation ~agit&,the ~ r k was our chart, or star-hop 20 southm 13 Vdpedae. hnbbell looks almost rectangubugh a 2.4-inch scope at low pow-
:veliusls holding u can se A fainte
4
out 1'12
Coathanger. The group is &3
Mbireo.
AD 946 as a little cloud. 1 mapped by Dalmiro F.
4
..
. . . , .
&
.
Use this map to star-hgp from
I
.
. I . Alb .- .. L---rL----( ...
.
a
.. a
tensions on each side that turn it rger football. Subtle variations in ess become visible in the appleet of the nebula, including a nar-
.
VULPECULA
ve at a loose
hi's Cluster,
.
;or the
hangs upside down
.a
&
r visible to xibed by the ayn d-sfiffi~ :1920s it
,, chartmaker
n our ch& at right. Draw a line through 41,continue oil for the stance, and you come to NGC 6940 dim open cluster. A 2.4-inch tele-
..-_I
AGITTA:
.
-
a
I . :
.
-------
bi
,--.J----
-.i._ "
.
I
.
-
P' -.--.
Octobere November December
....
...
........ x -.
.
>::&. $*. . . . -...*c2C:~~:.rtp?im?,.w1~q .......x*~. ... ;:, . / . . . . .. .. ..... a?: %*&?I , ,.,+..:,-.,..'..?*.,.. .,
-*j;j-,
.,
. :,I.:
.
,
,.
; ? . ! : , ; > : . , '
......... ;:w. . ~
octo4u Follow that Swan! ........................ On the Wings of a Swan
uo
..................132
The Arrow and the Dolphin ............. .134 Messier Hunting with the Horse and the Water Boy ...................... .l36
A Fish Tail to Get Your Goat ............. ,138
At this tine of year the no& -, . .
ern sky holds a t r e d s u r e h
'T
#..,
1.
of deep-sky deq-sky riches in Ce@ C A Regal T'keasure-T'kove . .......
Way with more fine s;ghts in
-
m -WE
cygn&, sagitta,.&)ler -
-
.
:*'
There you'll find a
.......................150 File Under W ........................... .152 A Queen's Ransom .......................I54 Local C d s ................................156
double stars, a magnificent
Sculpting at the South Galactic Pole
Cassiopeia's Chair
>If,.
constellitions. But don't ignore the rest of the hea
galaxy, and a beautiful pknetary nebula.
.:.;!Q /
......158
I
- 2
Celestial Sampler
Wwrphr 4.
October
I
you." It is quite subtle and takes careful you have spent at least 20 minutes in before attempting to see the North America give your eyes time to adapt and e faint glow much easier to perceive. teresting double star 5" south of Xi rms a nearb perfect parallelogram with the ~ e n e b~, a d rand , Epsilon (E). ~ 0 t compoh are orange-dwarf stars, and their cur31" makes them an easy split for a 30x. The brighter component is the companion is magnitude 6.0. astronomer Giuseppe Razz&
Follow That Swan! is nearly centered on the all-sky map on page 29. He is flying high overhead along the hazy band of the Mdky Way with his wings outspread - his head marked by Albireo and his tail by the bright star Deneb. Let's shadow Cygnus and see what celestial sights he leaves in his wake. We'll start well behind the Swan's tail with M39, the splashiest object in this essay's observing project. Aristotle may have been the first to record this star cluster in about 325 BC1describing it as cometary to his unaided eye. Messier 39 is a difficult naked-eye target but rather easy in binoculars. Sweep for it about threefourths of the way from Deneb to the 4th-magnitude ~2 ( ~ 2~ ) y g n iA . 3.6-inch (92-millimeter)telescope at 25x will show two dozen mixed bright and faint stars gathered in an equilateral triangle about the size of the full Moon. The cluster lies in a rich field of the fainter background stars of the Milky Way When you gaze at the hazy band of the Mdky Way you are looking at a vast number of distant stars along the plane of our disk-shaped galaxy. It's a sight reserved for those who observe well away from outdoor lighting. The Milky Way is irregular - cleft and spotted with patches of darkness. These dark areas are not starless voids; they are clouds of interstellar dust dark nebulae - blocking the light of the stars beyond. Cygnus happens to contain the first dark nebula ever cataloged. Le Gentil3 is the third object listed in a scient&c paper that was resented by the French astronomer Guillaurne Le Gend in 1749 and published in 1755. Le e n d 3 can be seen with the naked eye or binoculars as a dark lane jutting across the M i . k ~Way CYGNUS, THE SWAN,
*
OCTOBER
cope this star has "flownn a Moon's diameter northeast,
s.. ,&I,
,
>
A
.
, ,
America" is the Pelican Nebula.
is the 14th-closest star system to and the 4th closest of those visidark nebulae can also be found great, dark rift that runs dong the sout Swan's body and is easily visible to the unaide dark skies. The end of this rift near Deneb is th Northern coalsack. ject listed in J.L. E. Dreyer's famous New Gen logue of 1888. Lying between Deneb and the 4 tude star Xi (5)Cygni, this m a d c e starbirth spans z1/2" of sky, or five full-Moo - but don't try to find it when the Moon is NGC 7000 (Caldwell 20) is faintly vis
refractor and an eyepiece givin drawing makes it obvious why
The North America Nebula is a popular camera Photographs like this one by Alberta, often bring out the nebula's vivid
150-mm focal length at fl4.5 for this 30-minut sure on Kodak Pro PPF 400 film.
4.6
900
Dark nebula
-
-
NGC 7000
Bright nebula
-
5007
61 C Y ~
Double star
5.2, 6.0
11.4
Open cluster
6.6
4,000
Planetary nebul
8.8
5,100
NGC 6826
the German astronomer
ters in Charles Messier's cat-
e count to 15 stars or so. But M29's appearance as a clusastronomy-club members
This is also the brightest la. Small telescopes with greater than about 750 m pass the entire nebula in that case you should concentrate on
Open cluster
Le ,-enti[
M39
g Planetary. It lies zl/zO t of the 4th-magnitude star Iota and just 11/2" east of the slightly
NOVEMBER
Star, but at 50x it starts to reveal its true nature. A 4inch scope will show NGC 6826, also called Caldwell 15, as a small, round, bluish green (planetlike)disk. At loox to 150x the nebula appears slightly oval and you can see its 10th-magnitude central star. Staring at this star with a 6-inch scope makes the nebula fade from view. But if you look a little off to one side of the star (use averted vision), the light from the nebula falls on a more sensitive area of the eye's retina and the planetary reappears. Alternating the two views produces a blinking effect, which gives this nebula its common name.
I used the lowest available "ewer, 17% to obtain a field of 31/20 wide for this negative drawing (dark stars, white sky) North America Nebula with my 4.1-inch Astro-Physics Trav
.
DECEMBER
Chapkr 4:
I October
I
I
On the Wings of a S
ghdes through the zenith on October's all-sky star chart on page 29. The leading edge of its outstretched wings are formed by Iota (t), Delta (6),Gamma (y), Epsilon (E), and Zeta (6) Cygni. Myriad deepsky marvels, many within the grasp of small telescopes, nestle up to this distinctive line of stars. We'll launch our tour with the planetary nebula NGC 6826, also h o w n as Caldwell15, near Iota in the Swan's northern wingtip. Iota shares the same finder field with 4th-magnitude Theta (8) and 6th-magnitudec 16 Cygni. Centering 16 Cygni and viewing it with a lowpower eyepiece will reveal a pretty pair of nearly matched yellow suns. Wait three minutes, and the slow westward march of the stars will bring NGC 6826 to the center of the field for you. The nebula will apwar tiny, but nonstellar, at 50x. Boosting the magnification to 127x on my 4.1-inch (105-millimeter)refractor unveils a slightly oval robin's-egg-blue disk with a 10th-magnitude central star. Turn to the previous page to discover why NGC 6826 is nicknamed the Blinking Planetary. Now let's move to the open cluster NGC 6811, located 1.8" northwest of Delta in the same finder field. My small refractor at 87x shows a 15' swarm of about 40 faint to very faint stars in a nearly equilateral triangle. The cluster resembles an arrow with a fat head pointing west-southwest and a slender, slanted stalk. There's a paucity of stars in the center of the triangle. Deep-Sky Wonders columnist Walter Scott Houston called for observations of NGC 6811 after a reader from Denmark likened it to a smoke ring of stars with a dark band running through its middle (S7zy & Zl?lescope: October 1986, page 426). The ensuing r e p o h included CYGNUS, THE SWAN,
:
Celestial Sampler
OCTOBER
NOVEMBER
DECEMBER
k,
dimmer stars join the scene. 6960, or Caldwell34, is a bit fainter than NGC 699215 910 is embedded in an obscure section of IC but quite charming. It widens and forks to the south of elaborate expanse of broken nebulosity sur52 Cygni, while to the star's north it tapers to a point. g Gamma Cygni. With a wide-field eyepiece givIf you center this northern tip in a low-power field, x and a field of 3.6", my little refractor reveals this you can scan eastward to find NGC 699215. astounding complex. The three brightest patchA wide-angle eyepiece taking in both these large arcs o northwest, 0.8" east-northeast, and 1.1" eastoffers perhaps the most engaging view. My sketch at ,east of Gamma. Each is aligned roughly northeast 17x (opposite) shows a 3.6" field that nicely frames the lthwest and appears about 30' to 40' long. To me entire Veil. The very faint wedge of nebulosity suseld stars seem to grow fainter toward Gamma, alpended between the northern ends of the brighter arcs as if it were sitting at the bottom of a funnel. is known as Simeis 229 or Pickeringls Triangular Wisp. rting Gamma Cygni in the western part of a lowHarvard astronomer Edward C. Pickering mentioned r field and scanning 1.8" south will bring us to this feature in 1906 after a long-exposure Veil photo~t 87x, I see a small, pretty gathering of six 9thgraph was examined by the observatory's first curator dtude stars arranged in back-to-back parentheses of astronomical plates, Williamina Fleming. :ee stars each. Ten dimmer stars are Med across the cluster. M29 has described in some observing guides .e Sights ,per or a tiny ~leiades. I Mag. Trpa Bill Ferris finds.the re--. lance so remarkable that he calls nebul 1 NGC 6826 Ptanetary the "Little Sisters." Color images " - of star l6 Cygni coup display a nice mix of blue and s stars. NGC 6811 Open cluster !U find our next target, Ruprecht 173, vovv ,wn cluster 7.6 ICY ers of the way from HGC 6910 )pen cluster n Cygni. Only low pow$.verylarge, coarse open imission nebula IC 1318 er well. At 17x, I see 60 stars of 6th 3psn cluster M29 litude and fainter in 50'. Many of the ' Ruprecht 17 )pen cluster arranged in a nearly ugure 8 with a fatter and X Cygni lariable star half. A rich M.llky Way Veil Nebula Supernova remn ant 2.9" ong and partly into the Approximate angulc#rsizes are from catolc)gs or ph tographs. Mo!it objects appear somewhat smaller in a telescope used le group, where the vari- -$tar X Cygni resides.,This pulsating r supergiant goes from around mag5.9 to 6.9 and back in a period of ys. At its peak X Cygni is the cluslrightest star. k final stop is the beautiful Veil Nebula. bpernova remnant is a lovely sight dl telescope, but unless you obider very dark skies you'll need I filter (one blocking most light ex:en) for a good view. dghtest section of the Veil bears ignations NGC 6992 and NGC nd together they are Caldwell33. und a little southwest of a spot between Epsilon and Zeta Cygni. ntly curving arc of gossamer light than lolong and runs approxinorth-south. The southern end 1 and feathers out into ghostly tenwhing toward the west. Veil's other major part harbors the ye star 52 Cygni, and for t e s rea1y people prefer to start their visit 'eil here. This section, called NGC
-
-
....... I'IUL
-
Celestial Sampber
$
133
CkOPfhC 4: ct, but the embedded one is a yellow ed to be a member of the group. 's move to the nose of the Dolphin, where two nice double stars. The golden star marksnout is 4th-magnitude Gamma (y) Deli. ~hrougha telescope, a 7th-magnitude star of simuth-southeast, sharing a low-power . My little refractor at 28x reveals both stars as doustiU quite closel At 47x you'll get a e air is unsteady don't be surprised need to double that magnification. Gamma conf a 4.4-magnitudeyellow-orange primary and a contrasting, 5io-magnitude yellow-white com9" to the west. The dimmer pair, nns,is a 7.5an 8.2-magnitude secondary 6" to
D~~+us, the Dolphin, appears to be leaping out of thR "watery" constellations to the south and east (see p w 29). Nearby Sagittal the ~ r - o wseems , poised for a night over the Dolphin's head. while diminutive in size, Delphinus and Sagitta are in an area of the sky rife with deepsky splendors. We'll begin our tour in Sagitta wlth M7*, which long suffered an identity crisis. Some astronomers maintained that ~ 7 1 an open star cluster like the Beehive or the Pleiades, but richer. otherszontended that it was a globular cluster like ~ 1 in3Hercules, o d y looskr. A recent in the-latter meeting of the minds has placed it Category- much to the relief of the cluste~~ no .doubtMT~ poses prettily between Delta (6)and Gamma ($ Sagittae, two 4th-magnitude orange in the body of the "arrow.~ o o for k it about halfwaybetween the stars
ON OCTOBER EVENINGS
OCTOBER
NOVEMBER
DECEMBER
1.4'. This should bring you to the Toadstool, an asterism of 9th- through 12th-magnitudestars about U' across. My little scope at 68x shows the celestial mushroom's stem formed by five stars in a V shape opening toward the northeast. The top of the eight-star cap faces southwest. The Toadstool's shape shows very well in the MUennium Star Arkas, which plots 11of the u stars visible through my little refractor. Deepsky writer Philip S. -@on sees these stars grouped differentlgr; he's dubbed them Dolphin's Diamonds. While asterisms are generally chance alignments of stars with no astrophysical sigdicance, I find their eye-catching shapes enchanting. Do you have a favorite asterism?
e seen near Beta (p) e opposite corner of
.-.
ubject
ec.
22725 22703
Toadstool
group engulfing the eastern m Most sizes or separations ore cntalog values. Most objects appear somewhat smaller in a telescope used visuallv.
At low powerl you rn
center of yo^ field of view. se who prefer to skip the wait, try slowly eastward with your lowest-power eyepiece.
mg back to low power, position NGC 7006 a uth of center and continue east for another
ews above the chart'rnclude stors to magnitude 11ftom ium Star Atlas along with two fainter stars, marked x, that
..-.
5 visua target even m large amateur instruments.
magnitude NGC 7009 will be the brighqest object in the northeast. At 29x in my 4.1-inch scope the plan* looks stellar, and at 153x it appears small, oval, and bluish gray The faint extensions or ansae that give NGC 7009 (CaldweU.55)its Saturn-like appearance are not easily visible in scopes less than l o inches in aperture.
@find M15, draw a line from Theta (8) to Epsilon (e) rsiand continue for a little more than half that disagain. Golden-hued Epsilon is also known as and it marks the horse's nose. At magnitude 6.4, ihas been spotted with the unaided eye under aery iskies by some keen-sighted observers. Though a 1 finder . it resembles . .an.out?f-focus . -stq. My 14 x
,
Messier Hhnting with the Horse and the Wate: OBSERVING ALL the Messier objects is a god pursued by many amateur astronomers and a fine way to hone your observing skills. A good 3-inch (75-mill~meter) telescope under moderately dark skies is sufficient to bag them all. Here we'll ferret out the Messier objects of Pegasus and Aquarius. While two objects are easy targets for a small telescope, the other two may prove to be a challenge. Let's start with the constellation Pegasus, which contains the brightest and easiest to find of the four Messiers. The 18th-century astronomer Jean-Dominique Maraldils interest in de Chtseauxls Comet (which appeared in August 1746)led him to discover two of this month's globular clusters, M15 and M2. On September 7, 1746, he observed M15 as "a fairly bright, nebulous star which is composed of many stars," a somewhat perplexing description. Look for Mi5 (the Great Pegasus Cluster) just off the nose of Pegasus, the Flying Horse. This cluster may have the densest core of any globular in our galaxy. It is theorized that M15's stars fell toward its center within the first few million years of the groupls 12-billionyear lifetime. ~ l t h o u g hno globular cluster is unam-
.
1
Look in Pegasus for M15 (left) and about a fist-wi below it for M2 (right) in Aquarius. These globulm in brightness, though M2 is o little dimmer and fa
t
biguously known to contain a central bla is considered a good can one with 2,000 solar ma density may simply be due remnants such as neutron M15 is also the first glob planetary nebula - Pease telescopes as small as lo inches but is c
,,
-2
,the cluster appears disthm oval and sparkles many very faint stars. objects, M72 and M73, are located tlthwestern Aquarius, and if yould like to observe ntire Messier catalog, youlll need to tackle these idiibcult targets. 1 is locited 3.3" south-southeast of 3.8-magnitude on (E) Aquarii and is the faintest globular cluster iessierls list at magnitude 9.3. An impressive
.
D dim Messier
~ w ,
.*
. :.*
Telescope's b
.
-..
9
.
. .
hows a very small and dim fuzzy patch. A 9.4litude star lies 5' to the east-southeax. At 1.27~in %inch refractor'the cluster appeam ris no true resolution into stws. k last Messier object is M73, found 9 ; e . d Don't blink or you'll miss it1 M73 rn an asterism of unrelated stars, ; it might be a multiple-star system ) kspersed cluster. M73 consists of L des 10.3, u.1, 11.9,and 11.9 in a'P mere 1' across. Use magnificatioha darken the sky background and he&
.-
.
.. .
,
,. *p*
*.
... . . -
.
'. ..
..
.- .
-.
.
.
. .. t ' .
.. . .... . . .. *-' , . * . . . . ' * ; . : . : . . - . . . . . . . . . . ..r . . . *25, . ' . .. . . . . 26,. .'. : .. . . ... . . '* . . ' . * . . .. -. . *@Biz'. .; .*. . ..0".-
i
'
.
.
.
*:*.
*
.;*
.
. . 5 .
'.*,
-4
f.
9
.
I
.
'
'
r.
I .
..
.
,'
- e *
. 0.
.,
0
u donlt find ~ 7 3 ~ u f f i c i e n challenging-4 dy e that gives about a 1" field of view. Put M73 tern edge of the field and you will see a 7.1-3
.
_1
.
..
-.a
..
?-:Fig
star near me nortnern edge. YOSlOOn tnat ar the southwestern edge of the field and 8.3-
t
Luue
2elestial Sampler
hart north is up and east is left. The circles show fields of typical findencope or a small telescope with a low-pow6 To find north through your eyepiece, nudge your telescol olaris; new sky enters the view from the north edpe.
':.'
-
--*
.
~~
A
C)#m 4: -magnitudebluish secondary 205" to the west and magnitude tertiary 227" to the southeast. m Beta Cap, drop 4.3" south to 5th-magnitude
1 AFishTail to Get Your Goat
OCTOBER
NOVEMBER
DECEMBER
Those who live farther south can see M30 higher in the sky and might pick out details that 1 usually need a larger telescope to see. At high powers this globular
1
.td
is due south on this month's all-sky star chart on page 29. Capricornus is commonly called the Sea Goat, though its name liter* means Goat Horn. In Greco-Roman mythology, the Sea Goat is often associated with the god Pan. It is said that the Olympian gods were feasting along the banks of the Nile when Pan warned them that the dreadful monster m h o n was approaching. The gods quickly disguised themselves as animals, but in a panic (a word derived from his name) Pan leapt into the river - where the part of his body below water became a fish and the portion above became a goat. This story was apparently concocted to explain a
THE CONSTELLATION CAPRICORNUS
F V ~ Q + I I Vnf ~ .,A.,"CUI'
"I
r n ~ ~ rmnrp h ampipnt LYuv-
-v--
won't get your goat.
ary looks white and the 7th" to the southwest appears
--- the --- Sllmeri-
nrioin from
I-------
ans perhaps five or six millenia ago. Their Lord of the E&, E&, came to be symbolized by a goat-fish or ram-fish, which worked its way into the sky sometime during the first millennium BC. When the Greeksbystematized the sims of the zodiac more than 2,000 fo: years ago, the Goat was indeed a this sky region. At that time the Sun solstice, its lowest point in the sky, nus. What better animal than a goat for climbing out of winter's de~thslThe latitude on Earth over which the Sun hove& on the Deeember solstice is still called
the Tropic of Cap1 ago moved the sol The head of the Ca)ricorni, also h o w n as Algedi. It stars that are far enough apart (381 0.1~) to split with the unaided eye. colored in binoculars or a small 4.1-inch (105-millimeter)refractor a1appears yellow
f Omicron, I see Pi as uish. I used 118x to isolate magnitude companion lying
,
Capricomi is the brightest Sea Goat and can help in our final target, the globular
rn
I I
center and seven faint e outer halo. The halo
Above: The prei M30 is an easy west-northwest caprimrni. comus as ima it with the mop
area of the eye's retina). e cluster appears about 5' my scope, though it is catabeing more than twice as 9th-magnitude field star lies
Cekstial Sampler
* 139
-&
LAC'ERTA
,
Lacerta, the Lizard, appears to be scuttling up from Pegosus to Cepheus. Look for three open clusters lying between the Lizard's zigzag-shaped body ond one of W t r e t c h e d wings of Cygnus, the Swan, to its west. ,.
~
.-0
* Celestial Sampler
DECEMBER
Lacertae. You can find it by drawing a line from orangish 4.3-magnitude 5 Lacertae through 4.6-magnitude 4 Lacertae and continuing for exactly twice that ~ exdistance again. Most of the stars in IC 1 4 are tremely dim, but using high magmfications will darken the sky background and help unveil their feeble light. My little scope at 17x shows a faint, fuzzy patch with four dim stars. At 87x, I see five moderately bright and several extremely faint stars over a misty background about 7' across. Four of the brighter stars,are arranged in a simple kite shape with the brightest of the five to their southeast. A power of 153x brings out many barely perceptible stars glittering over a patchy haze. Although nearly barren to the naked eye, the Lizard harbors deep-skg treasures well worth seeking. Next we'll go looking for more deep-sky wonders in the constellation immediately to the east of Lacerta.
I Leaping Lizards LACERTA, THE LIZARD, is a modem constellation introduced by Johannes Hevelius in his 1687 atlas, Uranographia. He also referred to Lacerta as Stellio, the Stellion - a coastal Mediterranean newt with starlike markings on its back. Lacerta zigzags across the Milky Way above Pegasus, the Winged Horse, and just northeast of Cygnus, the Swan. Our celestial lizard is an inconspicuous constellation whose brightest star shines at magnitude 3.8, but from a dark location it adorns the sky with a pretty sprinkling of faint stars scattered across the haze between the brighter Milky Way constellations of Cygnus and Cassiopeia. Only two stars in Lacerta have Bayer Greek-letter designations: white, 3.8-magnitude Alpha (a)Lacertae, and yellow-orange, 4.4-magnitude Beta (P) Lacertae. Our first celestial target is the open cluster NGC 7243, lying approximately 2.6" west of Alpha and making an isosceles.. triangle . with Alpha and Beta. This book often highlights objects (prefacedby the letter M) from Charles Messier's catalog, which includes some of the brightest and best treasures of the deep sky. But there are many other sma-scope wonders to be found, particularly in the New General Catalogue of Nebukre and Clusters of Stars (NGC) compiled by John Dreyer in 1888. Although many of the 7,840 NGC entries are beyond the reach of a small telescope or binoculars, NGC 7243 is one object that is approachable through both. In fact, it is included in the Astronomical League Deep Sky Binocular Club's list of 60
OCTOBER NOVEMBER
r
-
-----_c-_I
Prpttv tights in a Faint Constellation
The open clusters NGC 7209 (above) and NG( make good targets for observers with binoculars scopes. Look for them just slightly to the west of up in both imoges.
non-Messier objects obse ~tis also number C16 in the Caldwell British astronomer and astronomy po Caldwell-Moore. In my 8 x 50 finder I can pick out s stars in NGC 7243 over a hazy backgro while observing t h s group through 14 1nicknamed it the Broken Heart. To me est stars roughly outline a heart symbol along one side where one of the stars se misplaced. AU likeness t my 4.1-inch refractor, however, which moderately bright to faint stars within stars are distributed in clumps surroun isosceles triangle of one loth- and two 9 stars. The southeastem corn double star Z2890. Its 9.3-ma up to a 9.7-magnitude c northeast. A second cluster from the resides in Lacerta. NGC 7209 can be fo southwest of NGC 7243 and 2.7" due we
te4e orth is
:ulars. led by atrick
fain1 7
dm. dght
'pen .tly lough ut 5(
The l tral
~tude he
NGC 7243
Open cluster
22890
Double star
NGC 7209
Open cluster
--."
..--. ..-. RA . .;Dee. .1,800
[email protected]" $;$go 5:
i
a . 6.5
*.I
9.
-
2,800
,
3,OOO
%zh 15.2" :++y5;
-
$zh
05.2" t g 6 ' 3~
7209 contains the ex-eclipsing binary SJ Laterd a dip in bri&tness when one passed in front of the other. Studies indicate gan in the late 1800s and e middle of the 20th cen-. or has been attributed to an unseen tem whose gravitational perturbaamics of the system, SS Lacertae is e white star in the southwestant of NGC 7209. The intricate dance of these e eclipses for Earthly obntil at least sometime in the 4th millennium. 1.4"south of NGC 7209 is an attractive m e of n which to try your color perception. Their mags from north to south are 6.2, 6.5, and 5.1. gh my 4.1-inch refractor I see them as white, 1 and yellow-orange. What colors do you perceive? New General Catalogue was followed by two s u p (ICJin 1895 and 1908. Toal 5,386 objects. M b y of are quite faint, but the open cluster IC erta is within the reach of a small tele" west-northwest of Beta hart north is up and east is left. The circles show fields of view all telescope with a low-power e y e rough your eyepiece, nudge your telescope loris; new sky enters the view from the north edge. (If you're gonal it probobly gives a mirror hnage. Take see an image that matches the map.)
Celestial Sampler
*
i-
-
& OCTOBER NOVEMBER DECEMBER
NGC 7331 is the brightest galaxy in Pegasus. Al-
of November offer many of us in the Northern Hemisphere a threefold blessing: early darkness, bug-free observing, and frequently transparent skies. They also harbor a panoply of deep-sky wonders for anyone with a small telescope. This time we'll seek a group of objects that gather around zenith for observers in north temperate climes. Looking at our all-sky chart (page 30), just above the Z in the label Zenith, you'll see a curve of three 4th-magnitude stars belonging to the constellation Andromeda. In the night sky you can locate this group of stars by noting its position above a distinctive and very large star pattern - the Great Square of Pegasus (see page 136 for a photograph of this asterism). AnThe southernmost star in the curve is Iota-(L) dromedae, whch will serve as the point of departure for our journey. Some 20 west and a little south of Iota, you'll see the 6th-magnitude star 13 Andromedae the brightest star in the area. Our first target, the tiny planetary nebula NGC 7662 or Caldwell22, lies 26' south-southwest of 13 Andromedae in the same lowpower field. At first glance it masquerades as a 9thmagnitude star. My 4.1-inch refractor at 87x shows a small, round, faintly bluish disk with an elusive, starlike point in one side. Increasing the maglufication to 153x, 1 detect a slightly oval shape elongated northeast to southwest. Occasionally there are hints of a small, slightly darker center. Planetary nebulae were so named because many of them resemble the blue-green disks of the planets Uranus and Neptune. The color of NGC 7662 becomes more obvious with larger scopes. and it has earned the
THE CRISP NIGHTS
¤
~b. You could almost hide the whole area with a fist bidtht arm's length, yet spend an whole evening enj@yhqthe sights it covers.
at pot all three c o m p o n m -d & IW at 17x my 4.1-inch scope, and&ey are
split at 47x. The 7.9-ma@ntQde, -white primary has a 9.7-mgnitude q 55" to the west and a Yo.%magtertiary 38" to the northwest. They nice isosceles triangle, small and the companion stars seem to different hues, the colors are
Autumn Sights
1
-. -
NGC 7662
NGC 7 3 3 1
than 14th magnitude and well beyond reach of a (visually).
neb-
b as
their overall brightness, meaning that would shine with the light of an llth-ma its glow were gathered into a single Po light is actually spread over a it has a very low surface brightness.
tude orange star. Continue in the same
r. Can you see the difference? Ho 197 we'll sweep 3.6" westest to locate the beautiful double 5 in the southeastern corner of the The 5.7-magnitude, the brightest star in ting orange hue. The h in the name this is one of John Herschel's dis-
find it, place h975 at the northern a low-power eyepiece field and " westward. You should spot an si, the 2.5-magnitude star marking ern corner of the Great Square of Pe-
The dim stars of this region occupy a h of sky that is practically overhead for
a
NGC 7640
h975
as Uisa do
Nicknamed the Blue Snowball by observers, the planetary nebula NGC 7662 has a flowerlike structure in images made with long-focus telescopes. This CCD view by William McLaughlin was taken with a 12K-inch Ritchey-ChrBtien reflector.
structure and inclination toward us as the Andromeda Galaxy (see page l.54).But since it is about zo times farther a v , we see it as a much smallerand dimmer version of its famous cowin.
righter, elongated core. If you snare this h k star city, Fur eyes will be collecting photon8 h m axy that has gone unnoticed by many observers
.
.
w
,-
Q#pkr 4: OCTOBER NOVEMBER DECEMBER
stars lie halfway between, helping pinpoint the
1
Hunting Down the
the Helix Nebula is one of the most beautiful objects in the heavens. It earns its name from a double-ringed appearance on photographs, like looking down at two coils of a spring. Long-exposure photos show nebulous fingers pointing inward from the ring toward the central star. The Hubble Space Telescope captured stunning close-ups of these radial filaments, showing each with a cometlike head and a gossamer tail. (Go to the HST Web site at http://hubblesite.org/gallery and search for Helix.) Also known as NGC 7293 and Caldwell63, the Helix Nebula is one of the nearest and brightest of the class of objects known as planetary nebulae. A planetary nebula is born of an aging star that exhausts itsnuclear fuel and sheds its outer layers into space. As the nebula expands, the core of the star is exposed. This hot, dense cinder will evolve into a white-dwarf star and then slowly cool over billions of years. Observationally, the Helix is one of the easiest of bright planetaries and one of the most elusive. It can
WITHOUT A DOUBT,
e the nebula better, and 0 III and narrowband filters often work well. At high power, some faint stars can be seen embedded aphs? While you can't observe the wealth of
.'
site near Brooklyn, Wisconsin, Bill Ferris made this
oxygen lII filter improves the view so much; it passes the blue-green light given off by doubly ionized oxygen (designated 0 m)while blocking the colors common to many sources of light pollution. Irregularities in the brightness of the ring also start to show up with an 8-inch scope. The two "coils of the springnhave been clearly seen by Bill Ferris of Flagstaff, Arizona, using a lo-inch reflector and 0 I l l filter. Like many planetaries, the Helix has a faint outer halo, but it doesn't show on most photographs. The brightest section emanates from the southeastern edge, spirals out clockwise, and fades in the north. While this halo has been suspected in a loinch, a 20-inch is the smallest scope I know of in which it has been described as apparent. Another tough target is a 16th-magnitude galaxy embedded in the northwestern edge of the annulus. It is located 1.2' south of h e prominent 9.9-magnitude star at that end and has been seen in a 17lIz-inch scope. And what about those radial spokes? The streamers have been seen in a 16-inch and hints of the cometary globules at their ends with a 22rinch. Many of these observations were made by very experienced deep-sky enthusiasts. Some of them observe from darker skies and-&ore southerly latitudes than most of us enjoy, but their accomplishments give us something to strive for. When trying to nab any of these features, choose nights of good transparency and the darkest sky you can find.
overhead, Maurice Clark and his friends have at 63x. "The transparency was exceptional that night North is up. Compare Bill's sketch to Gary L. Stevens' at left.
be seen in binoculars and yet re
a single point, it would shine with t
color than to the reddish hue that
lix is a good small-scope target.
!. 'CAPRI
silon will make your nebula search
ka$cis striking view of the Helix, Gary L. Stevens took his Takahashi 152mit%R@&r refmctor to Mount Pinos. California. on July 4.2000. This image is 0 =pSS&E of seven white-light exposures at f/6 and three more through color fil&qjan SBIG ST-8E CCD camera. The total exposure time was 100 minutes. W h i s ~ a c r o s s .
m
144
* celestial sampi&
1
southwest for 4.7-magnitude 66 Aq in the same finder field with Delta
white Upsilon, the brightest star in
Celestial Sampler
4
145
ch##f
I November
L
Milky Way east of Cygnus passes through the ~ ~ l l a tCepheus, i ~ s the King, and Copsiopeia, his Qaecn. They're nearly overhead whm you face north m m d the time of our evening sky map on page 30. Many dcepsky wondue foremdl tclcwupes reside in this royal reaim. This time we'll look through the section o i the MiElrg Way where-C and Cmsiopeia met.Ywcan use the map at .a+ghz&&prn ttksmpe to muhrof? from the b~.%&t,laadm& -o&osaip&% w HIGH IN THE AUTUMN SX&
4
..
?
.i2.
.
pattern to each of our chosen sights. Draw a line fmm bright Alpha (a)Caq through Beta (p) and continue the ha tle more than the same distance. This 4 the open star cluster Y52. It's just sou& magnitude star 4 Cassiopeiae. Both t h g pretty orange stax fit into the same 1( ic field of view.,Binoculars or a large M52 as a small, faint, nebulous p a d (76-millimeter)telescope begins to rt ual stars. (Thebright star on the cl- edge is not a m e member of the g o s c o ~ at e 87x can resolve about o$
compare Delta's Litude 3.4, and Epyou look up on a I
a beautiful double
. In my 4.1-inch re-
Object
I
A richercluster lies 3 O southwestr
siopeiae, about halfway between the tude stars Rho (p) and Sigma (0).RQ
41 OCTOBER
star cluster and huge, dim emission nebula collectively known as IC 1396. The nebula may be dimly glunpsed in large binoculars or a low-power, rich-field telescope on a very dark, moonless night. Now turn the page to explore more of Cepheus, full of treasures truly fit for a King.
Mag.
Dist. (I-y)
Open cluster
6.9
4,600
1 Open cluster
6.7
7,600
Stock 12
Open cluster
7?
-
6 Cephei
Variable, double star
1.6-4.3,6.3
1,000
p Cephei
Variable red star
3.4-5.1
3,000?
NGC 7789
22819 22816
1
DECEMB
NGC 7789 (far left) and M52 (left) were photographed with identical equipment and exposures on the same night. In each case the field is 1"wide. Using the map below: The circles in the upper-left corner show the size of a typical finderscope's field of view (5") and a typical telescope's view with its lowest-power, widest-field eyepiece (lo).This indicates how much of the map you'll see at a time. Next, figure out directions. North is up and east is left on the mop. To find which way is north in your eyepiece view,nudge your telescope slightly toward Polaris; new sky enters the view from the north edge. Turn the map around to match. (If you're using a right-angle star diagonal at the eyepiece, i t probably gives a mirror image. Take i t out to see a correct image that will match the map.)
TYpe
M52
NOVEMBER
Double star Triple star
Above: Compare the star p
by Akira Fujii with the may per left. Inset: South of Mu nebula IC 1396. 1 was able 17x in a not entirely dark r naked eye was magnitude
Celestial Sampler
Celestial Sample~
der triangle. One comer of its short base is marked
and a little south of NGC 7510.
o behold them. But we haven't £in-.
Size
11'x 10'
Dist. (I-y)
RA
3.900
20h31.5m
+60° 39'
19 million
20h34.gm
+60° 09'
2,600
21h53.8m
+62' 36'
9,200
2Zh12.5m
+57O 17'
7,200
2Zh47.4m
+58O 08'
6,800
23h 11.1"'
+60° 34'
6,900
23h 15.2"
+60° 27'
23h 16m
+60.3O
&
OCTOBER
NOVEMBER
DECEMBER
I Cassiopeia's Chair THE CONSTELLATION CASSIOPEIA, the Queen, sports five bright stars arranged in a memorable pattern. Facing north on a June evening, we'd see it as a W-shaped asterism brushing the horizon. But now, a half year later, Cassiopeia rides high in the north and is nipped upside down like an M nestled in the misty band of the Milky Way while it's H c u l t to envision the Queen herself among these stars, some skygazers like to add the star Kappa (K)Casgiopeiae to create her chair, or throne (see the pair of sketches at lower right opposite). Kap pa is a prime example of the old saw "You can't judge a book by its cover? Althou* it looks dimmer than the other throne stars, this intenyb hot, blue supergiant is a whopping 480,000 times more luminous than ou Sun. The glory of the star is dimmed by interstellar dust w d by the &t that it lies some 3,300 lightyears away. It doesn't he& &at it emlts much of its energy in the form of u$&w, ultraviolet light. ' Numerous star cluF&&& wi ownradMessier able star. Since none b d q to the we catalog, they are sel& a t e d - yet many are within the grasp of a small s w . The hardest partabpbt observing these clusters is picking them out starrg: backdrop of the Milky Way This is cei&&dy true for our first three star Clusters. They are c e d l/3"nod-northwest of Kappa,. Wag =lies c l o s e ~ w ~ ~and p gis* . largest of the trio. &or& my 4.~g3dik*~refEactor at 8%, 3 aik?~eess &' ht%@~eqf&t
w,""
stars. Ivan R.King announced this clu! Harvard Observatory Bulletin 919. NGC il east of King 14, looking a little smaller stars. The two clusters are splayed out like a pair of narrow moth wings. NGC 1 smallest of the three, lying north-no& It consists of five loth- and nth-ma@ shape, along with a few even fainter These clusters aren't conspicuous, b form an interesting pattern. If Ring 3.4 are spread wings, NGC U3 could be a-4 posite side of the wings is a wedge-sha stars that is not part of these clusters: 9 profile of a bird's head capped by a %l reminding me of the crest of a pilead Now that you have a feel for what ta hunting clusters in a crowded setting;: farther afield. First we'll try NGC 225, w halfway from Kappa to Gamma (y) Caa inch scope at 59x reveals zo moderat4 faint stars in an irregular group 12' i r ~ d stand out fairly well in a relatively spm Way. N W 225 is one of seven& pearancesnrecorded by Caroline Herd ered it in 1784 with her 4.%hchhJe~anor seeker in southern England. j Next we'll move to NGC 129, a fair@j ter 2.7O south of Kappa. To pin d 0 d tice that the cluster is situated along'@ Gamma to Beta (p) Cassiopeiae. At 6 8 moderately bright stars in a right trim more to the north-nod& skinny kite. Some 30 fah kite in a looselv scattera
: mhfter than the d e e d $..-t;ucgclc~s* etY %OF
dF ,Theyait ~1.5~:west-s and are a shbrter st fi. e;
you put Beta at the
)Pa a.:. If
tern e clr er eyele US-
.....
.a
Cass~ope~o-s orlgnr is up; turn the book
'
is at .s Rap
The Chair
--
Celestial Sampler
* 151
Chapter 4:
OCTOBER
NOVEMBER
DECEMBER
Now draw an imaginary line from Delta through Chi
(x) Cassiopeiae; continue for almost PI2 times that dis-
1
File Under W
all-sky star chart on page 31, the prominent W traced by Cassiopeials brightest stars sits slightly above center. The bnght and easily recognized pattern will serve as our guidepost to some of the deepsky delights l e g beneath, or rather south of, this famous asterism. The beautiful double star Eta (q) Cauiopeiae will be our first stop. It is visible to the unaided eye one-third of the way from Alpha (a) to Gamma (y) Cassiopeiae and south of a line connecting them. Eta's components weigh in at magnitudes 3.5 and 7.4 and have been variously described by well-known double-star observers of the 19th century. Enghsh clergyman Thomas W. Webb called the pair yellow and pale garnet, Wilhelm Struve saw them as yellow add purple, and John Herschel and James South recorded them as red and green! With m$ 4.1-inch (105-millimeter)refractor, I see the brighter star as yellow and the dimmer one as red-
ON THIS MONTH'S
of this month's colorful little clusters, NGC 436 NGC 457 (facing page), were recorded by George R. his 14-inch Newtonian reflector at Lake Placid, New view is 2/30 wide. I see NGC 457 as the Dragonfly (no
TWO
dish orange, in good agreement with their types of GoV and MoV. The pair is split at widely so at 36x. The suffix 'Vn in
cluster WGC 457, though they may w e foreground objects. In my little scope at 87x, the 5th-magnitude primary appears yellow and the 7th-magnitude secondary looks blue-white. About 45 fainter stars are seen in a cluster that inspires imaginative flights of fancy In lOoo+: The Amateur Astronomer's Field Guide to Deep Sky Obseroing, author Tom Lorenzin calls it the ET Cluster after the cute extraterrestrial in the movie E. T. Lorenzin writes, 'ET waves his arms at you and winkslnThe two bright stars form ET1s eyes, sprinklings of stars northeast and southwest are his outstretched arms, and his feet extend northwest. Those big eyes lead quite naturally to
tance again to reach the pretty open cluster Stock 4. At 68x I see a group of about 50 faint stars in a more or less rectangular bunch, about 20' by 12', that runs west-northwest to east-southeast. A bar of fairly bright to faint stars lies just northeast of the cluster and runs northwest to southeast. A widely spaced pair of 8thmagnitude stars can be seen to the east. Stock 4 is one of the clusters discovered by Jurgen Stock and initially published in the first edition of the Cmbgue of Star Clirsters and hsociarioru (Prague, 1958). So far it has received little attention from either amateur or professional astronomers. Since today's large printed and software atlases often include some of the sky's more obscure objects, many pleasant discoveries s u c h a s ~ a ithe t notice of curious observers. Now dmp X.8" south-southeast to another attractive group, NGC 744. At 87x my little scope shows 15 faint to very faint stars over haze. Disconnected star bunches lie southwest, south, east-southeast, and east-northeast.
Attractions on High
a
your gaze upon the primary - a very just 1.30south-southeast of Eta, we
of Astronomy magazine. In a similar is somewhat more creative.
A narrowband light-pollution filter a bit, while a green oxygen III filter The nebula was discovered in the
~r somewhat smaller when a telescope is used visually.
Only later did Guillaume Bigourdan of
ham 1into a tiny trapezium ensc miniature Orion Nebula. Like its
f fluff at low power. At 28x in my ch refractor I can make out only a
nebula to shine. Thzsoft glow of NGC 281 can't be perceived as truly colorful by human eyes, but i t s y i ~ i ~ r e d h udominotes e this photographic image. Sean Walker used an 8j n & f e ~ $ ~ ~ w at ~ efl6.3 for this 55-minute exposure on Kodak E200 film. North is
Celestial Sampler
* 153
4: OCTOBER NOVEMBER DECEMBER
L
1 A Queen's Ransom rides high across the northem sky in the evening at this time of year. Her Wshaped star figure (currentlyupside down) ranks with Orion and the Big Dipper as one of the best-hown asterisms in the sky. Look for the W high in the north on the all-sky map on page 31. The Queen's mythological figure sits on a starry throne with her foot marked by Epsilon (E) Casand her slightly bowed siopeiae, her neck by Alpha (a), head by dimmer Zeta (6).In this essay we'll use the familiar stars of Cassiopeia to help us find a wealth of royal jewels. Along one line of the W lies an additional fairly a Cassiopeiae. Look for it about a third bright star, ~ t (q) of the way from Alpha Cas to the W1smiddle star, Gamma (y). Shining at magnitude 3.4, Eta is an easy find in suburban skies. It's a lovely double star that can be split at a magnification of 30x and resolved widely at 50x. The bright component is a very Sun-like star with a spectral class of GO. Sure enough, it looks yellow-white through my 4.1-inch refractor. The secondary star, 13 arcseconds to the northwest, is a type-MOred dwarf only as bright at magnitude 7.4. To me it looks orange. Our Queen is w e h g h pendant of topaz and hyacinth.
.
CASSIOPEIA, THE QUEEN,
.
e.,
.+
'
s
"
Above: Mi03 contains the bright triple star 2131 on its no edge. ~ i g h t :NGC 654 is a compact little cluster with a 7thmagnitude yellow star just to its south-southeast.
The Eta Cas system near for a naked-eye each other with a period of about 480 y range from 35 to 110astronomical units each orbit; by comparison, Pluto's Sun averages 40 a.u. The open star cluster NGC 457 is also cate. Draw a line from Epsilon through and continue on a bit less than half as far.
I particularly enjoy showing star parties. Open clusters are
Cluster. For me, NGC 457 will always be the dot game. what shape do There's more to this cl 13) than meets the eye. It may contain sand stars, but most are group's remarkable dist Gas is really a member of this cluster it must the intrinsically brighte 50,000 times as luminous as our sun! The only Messier object in this month' small open cluster that inch scope shows a dozen stars, and a 4around 20. The three brightest form the northeastern side; the companions 14" and 2 9.9 and 11.6, respectively. Ml03. ~ h r o u g hmy
4r
.
..., .' - * * * .
order of decreasing brightness the three stars have spectral classes of F5, and 64, suggesting colors of white, off-white, and pale yellow. Despite this I can't help but see the dimmest star as bluish. Color-contrast perception for double stars varies with their separations and brightnesses, as well as quirks of the observer and instrument. What do you see?
.::-+gerf .vg,t?:' :.,' .
;l.!?rt$
Jist. (I-y) I
L!
:L - '. ll:J"&
than twice as wide, and I can count 40 stars ranging from fairly bright to extremely faint. The four brightest are 9th magnitude and occur in two widely spaced pairs. This attractive group, also called Caldwell lo, has a central concentration of very faint stars. Both M103 and NGC 663 are part of a vaqt association of young stars h o w n as Cassiopeia 0B8. When you look at these stars you are gazing out to the Perseus Arm of our galaxy, the next spiral arm out from our Sun's (the Orion Arm). The two smder.open clusters NGC 654 and NGC 659 lie less than 1" north-northwest and south-southwest, respectively, bom NGC 663. Although faint, they are visible in a 2.4-inch scope as little nebulous spots. My 4.1-inch at 87x can resolve some of their stars. NGC 654 is the p~ettierof the two, with a dozen faint stars sprinkled over a patchy, hazy background. A brighter, 7th-magnitude y5llow star ges just outside the cluster's southern edge. NGC 659 is a little smaller and dimmer. Seven faint rough shape of a fat pie e overlie a dim, hazy background. of our star clusters lie dong the and legs. Her skirt is appar d with patterns of tiny diaoffset by an occasional colored
4
19
RA
oh49.1'
r
the size of a typical finderscope's
r
Finderscope's field of view:
*
will match the map.)
Telescope's
;62p'-
from Delta through Epsilon d continue for the same distance, and
.
....
Stars well to its east. Iota Cas has a -magnitude primary, a close and diffi de secondary star curat 87x through my 4.1solve the close pair. s system is 140 light-years away. In
u Celestial Sampler
* 155
QlPkr k bility with motion- Once YOU have the Pinwheel in view, use Do not look directly at the galaxy but off to one side instead- This idlow the light to fall on a more sensitive area of your eye's retina. At 47x, M33 -shows a we&& brighter core measuring 30' by 13' and running north to south with a slightly brighter, east-tomwest inner core. The outer halo is extrerne1y T2' zff, afld rnns ~orth-noaheast to south-southwest. The Pinwheel Galaxy contains NGC 604 - one of the grandest forming regions known. It is n loo times larger across than our galaxy's vast Orion Nebula (se page 46). This starbirth nest i northeast of M33's nucleus northwest of a 10.9-magnitudestar. The pair resembles a double star with one component that won9t quite come to focus. Though my 4.1-inch scope at 68x, NGC 604 looks like a very small smudge. Now let's return to our own galaxy, where we'll find the open star cluster NGC 752 (Caldwell28).You can sweep it up 2/5 of the way from magnitude Beta (p) Wan@ to 4th-magnitude Upsilon (u)Andromedae. This large cluster is best viewed with an eyepiece that gives
December
I Local Calls all-sky star chart on page 31, Andromeda glitters prominently at the zenith [the center of the chart).ncked away in this constellation is the brightest external galaxy visible from midnorthem latitudes - the Greot Andromeda Galaxy (M31). It's a member l a loosely bound family of about 40 of the ~ o c aGroup, galaxies including our own. Although MU is g e n e d y listed as the largest of the Local Group, two recent studies indicate that it may actually be a bit less massive than the one we call home. The Andromeda Galaxy is just barely visible to the unaided eye as a small, elongated, nebulous haze even in suburban skies. When you gaze at M31,you are seeing light that started its journey around 2.5 million years ago. We find the earliest mention of it in Persian astronomer alws Book of the Fixed Stars (AD 964), where hc referred to it as a "little claud." To find M31, draw a line from 2.1-magnitude Beta (B]Andromedae through 3.9-magnitude Mu (p)Andromedae and continue for that distance again. M31 is a treat through any telescope. At first glance you may see-onlythe galaxy's bright, oval heart, but cazeful study reveals much more. The faint, outer regions of M31 extend its length out to about 3". They sweep your telescope slowly are easier to no&+ou ON THIS MONTH'S
across them, since the eye sees better than stationary ones. The
found within a larger, slightly dimmer, oval 0
ground s h , while the northwestern boun abruptly. This sudden drop in brightnes tion of a dark lane inM31's spiral arms.
OCTOBER
NOVEMBER
DECEMBER
a 10or larger view. ~y little refractor at 4Tx a golden 7th-magnitude star as well as about 90 fainter stars spread loosely amass 47. of ~m~ of the stars seem to be arranged in crisscrossing chains. A pair of 6th-magnitude lies outside the southsouthwest border with one appearing golden and the other ormge. With increasing apemre, many tiond stars in this cluster reved subtle shades of ye& low, orange, and blue. -. e:
--
A
of M3lYsnucleus. Although it is much it has a lower surface brightness and is a irly its
northern end. Charles Messier discover in 1773yet did not fnclude it in his famo deepsky objects. In recognition of Mess1 NGC 205 has become popularly known as M The third-largest member of the LOC nearby 'lkiangulum. ~ 3the, Pinwheel meter of our g d q and 2.7 million light ~tis a notoriously difficult target for the n er. his spiral galaxy lies almost faceon SO pears nearly the size of two full MO With its Iight spread out over such a very low surface brightness and is eas by moonlight or light pollution. Despite seen through binoculars and has even
~ o o for k the Pinwheel 4.3" west-northwe magnitude Alpha (a) Tkianguli-To m chances of seeing it, use a low-power that gives you at least a lofield of view. slowly across the galaxy's position to e
V
? ve: Derails of NGC 752. R i e On ttrSs
chart nwth is up and east is Mt. ed white circlesshow fdds of vim ical finderscope (9or )a small t e k with a low-power eyepiece (10). To north through your eyepiece, nudge r telexope toward Polaris; new sky enthe view from the north edge. ( ~ymu' f re 9 a right-angle star diagaml, it probagives a mirnu image. Take it out to ~ e e image matching the map.)
, I\,..
1
PISCES
!
\If Q Pa7"&&7
e ---I---
.
- --
k D-
-
our line of sight. It is the brightest member of a small cluster of galaxies known as the Sculptor Group. At a distance of 10 million light-years, this is the closest galaxy cluster to the Local Group (the one in which our galaxy resides).The Silver Coin is also the closest star-
a-
sculpting at the South Galactic Pole
low in the south on the allsky ohan on page 31. It is a relative$ recent constellation, one of 13 introduced by the French ammo-L mer ~icolas-Louisde Lacaille to commemomte the instruments of art and science. Sculptor first - appeared on a chaxt in the Mhdm of the R o d Academy of sciences for 1752 (published in 1756) as L'Atelier du Sculpteur, the Sculptor's Wokshop. f i e chart depicted a carved b u t on a platform, a table, and three sculpting tools. skygazers wiU be hard-pressed to see the s d p torts studio among the stars. Sculptor contains o$ s i stars ~ of magnitude 5.0 and brighter, none bearing common names. The constellation's brightest star is 43-magnimde APha (a)sculptoris. you can pick it out ~ 6*byt ndg that the b e t -8 ~ Iota [I.) in a d B B P ~@) C a p o w tovd~dit. 9 at NUaPY&fe Alpha, weqbe..om s C d e o p e first moving r.70 n O + n o d w e ~ to a t j & I m m d e b e e star, $&XI cmt@irihg aloag.&e
burst high NOW rate galaxy, let's of turn star a title formation attention it e m sto in bythe its having core. &&magnitude an exceptionally star
YOU CAN SEE SCULPTOR
nitude appears in this 90-minute exposure at the 8-inch Schmidt-Cassegroin telescope. Jeffrey L. Jo ifornia. took it on September 1.1989. Right: Pho
w , ,P18
nitude 8.5. All illustrations in this article have no
=tor mag 'he ver the K.
uth Frthest ys disk. bf the nobressive !daxy
marked 6, for Delta Sculptoris, near the center of the chart above. Notice that Delta Scl lies about two-fifths of the way from the bright star Fomahaut to Beta Ceti and a little below the line between them. ~t is the brightest star in the area and a low-power double for a s m d telescope. The white primary has a 9th-rnagnitude secondary, 74" to the west-northwest, but it's too dim for me to make out any color. This companion,s spectral class is generally given as G (yellow),but it is described in the Webb Society's ~ i u a~lt k a sof ~ o u b k Stars as "intensely blue." Do you see any color here? After visiting Delta, star-hop 3.3O east-southeast to the 5.0-magnitude star Zeta (6)sculptoris. Zeta lies in the foreground of the large open cluster Blanco 1. With my 4.1-inch scope at 1 7 I~see a dozen fairly bright stars, mostly arranged in a V shape with one curved arm.Another dozen faint ---.stars are scattered in and around the degree-wide V, swelling its apparent size to about 1.4". Although Blanco 1 NGC 288 Globular clu does not stand out well NGC 253 Galaxy from surrounding stars, it 6 Scl Double star is a true cluster. The group was discovered in ~ l a n c oI open cluster 1949 by Victor M. Blanco, who noticed that the area NGC 7793 Galaxy contains five times the usual concentration (at . G similar galactic latitudes) of stars brighter than 9th . . . magnitude of spectral . P type AO. Recent studies have shown that this is a Young star cluster perhaps 90 million years old, similar in age to the Pleiades. It lies about 880
I
lorthor a ght in 20'
Y
-.
'
- > .
1
Finhlights of Sculptor
--RA Dist. (I-y) .27,OOQ
-26"
ii0:miI~lon.
Oh47.6m
-25" 17'
.. ... .. :1%4
23h 48.9"'
-28" 08'
Oh 04.2"'
-29" 56'
23h 57.8'
-32" 35'
.
.." ,
.
'
.. - @ 8 i
.
- 9niiliio": ,
m
.
I
.. . . .
2
"oh
born . 1.
.. .,I .
.
*
.
.
'. i . .t.
,
SCULPTOR
:
Oh52.8"'
,
.
.
I
,
that Blanco 1may have formed by a different mechanism than other nearby clusters. o we'll move exactly 3" From Zeta Scl in ~ l k c 1, south-southwestto our final deep-sky treasure, NGC 7793. This galaxy is never more than 14O above my horizon. Even though it's embedded in the skyglow from a nearby city, I find NGC 7793 to be reasonably obvious through my 4.1-inch scope. At 87x it looks fairly faint overall with a slightly brighter, small center. The 6'-by-4' oval is aligned nearly east-west. NGC 7793 is another spiral of the Sculptor Group. It displays short, asymmetric arms instead of the long, gracefuI arms seen in classic spirals. Such arms are probably created by ephemeral star-forming regions that are stretched into spiral-like shreds by galactic rotation. These shreds are short-lived in astronomical terms - about loo million years. Sculptor contains several other suitable for small-scope viewing. Given my v i e k g location in Upstate New York, I have picked out only the brightest of those in the northern reaches of the constellation. More southerly observers might want to take out a good atlas and look for some of the other treasures held by the constellation at our galaxy's south pole.
.
'23h ioIn
.
!
..
. !: L3h. 2 4,
.. 'I /. .' .*. - .I .
1
23"
.
'.
I
.
.
+
sition high above the galactic plane suggests
ith '
huge size of the galaxy NGC 253 is apparent from the fact that from the pair 9th-magnitude star off the oval's top edge is of similar stars below center. Jerry Lodriguss made this hour-long exposure on October 10,igg4, with an Astro-physics 130-millimeter f/8 StarFire refractor.
Celestial Sampler
hug the southemtern side. camline Herschel discovered NG(3 weep- the Sky for comets, a n phhment since thrs g a l q never Doabove the horizon at her obse N W 253 is a barred spiral galaxy,
tars
For deep-sky viewing this
while
month, check out the constellation of Sculptor just east of the
1-
.than
I
r&g*md. I to Celestial Sampler
* 159
ATLASES combridge Star Atlas, 3rd Edition Wil Tirion (Cambridge University Press)
Uranometria 2 0 0 0 . 0 Deep Sky Atlas Wil Tirion, Barry Rappaport, and Will Remaklus (Willmann-Bell)
Here's a basic atlas that's a good choice for skygazers who are still learning their way around the constellations. It contains a Moon map, monthly sky maps, and shows stars to magnitude 6.5 (plus nearly 900 deep-sky objects). A table of interesting telescopic targets accompanies each chart in the atlas.
This is an advanced star atlas with stars down to magnitude 9.75 and more than 30,000 non-stellar objects. It's great for pinning down those faint objects. It includes both 5th- and 6th-magnitude star charts to help you navigate the main atlas, has 26 close-up charts of crowded regions of the sky, and the index gives the chart numbers for all Messier, NGC, and IC objects (as well as those for bright stars and objects with common names). Uranometria 2000.0 comes in two overlap ping volumes - the northern sky and the southern sky.
Megastar 5 (~illmann-Bell)
This software atlas has more than 208,000 deep-sky objects, many of which can be overlaid with photographic images. Stars can be plotted from any of three included star atlases, which contain more than 15 million stars. The easy-to-use filters help you tailor the charts to your needs. (Requires Windows 95 or higher, 32 megabytes RAM, 40 megabytes hard-disk space, CD-ROMdrive.) Norton's Star Atlas and Reference Handbook, 20th Edition Ion Ridpath, editor (Pi Press)
It's similar in scope to the Cambridge Star Atlas, though it lacks the monthly sky maps. It does include a lengthy astronomy handbook.
Sky Atlas 2000.0, 2nd Edition Wil Tirion and Roger W. Sinnott (Sky Publishing)
This is a good atlas to use in conjunction with this book. It plots stars to magnitude 8.5 as well as 2,700 deep-sky objects. Included are handy close-up charts of some of the crowded regions of the sky. Sky Atlas 2 0 0 0 . 0 Companion, 2nd Edition Robert A. Strong and Roger W. Sinnott (Sky Publishing)
The text lists and briefly describes every object plotted on Sky Atlas 2000.0. Sky& Telescope's Pocket Sky Atlas (Sky Publishing) Here's a new star atlas that's great to use at the telescope because itls compact (6 by 9 inches) and spiral bound. It has 80 charts, more than 30,000 stars to magnitude 7.6, and Some 1,500 deep-sky objects. Also included are close-up charts of the Orion ~ e b u l region, a Pleiades, Virgo Galaxy Cluster, and Large Magellanic Cloud. & Telescope's Star Wheel Publishing) This planis~hereis a simplified "atlasnthat will show you ~hichconstellations are visible on any date and time. It's availablefor different latitudes.
Uranometria 2 0 0 0 . 0 Deep Sky Field Guide Murray Craigin and Emil Bonanno (Willmann-Bell)
This text contains useful data and a chart index for all the deep-sky objects included in Uranometria 2000.0. OBSERVING GUIDES Deep-Sky Companions: The Messier Objects Stephen James O'Meora (Sky Publishing)
Eke all the detail you can out of the Messier objects with the help of this detailed guide. Deep-Sky Companions: The Caldwell Objects Stephen James O'Meara (Sky Publishing)
Reach beyond the Messier objects with this in-depth look at some of the sky's most interesting deep-sky delights. Deep-Sky Wonders Walter Scott Houston, edited by Stephen James O'Meara (Sky Publishing) Here are selections from 48 years of the Sky & Telescope
column of the same name penned by Walter Scott Houston, who charmed us all with his journeys into the night sky. Observing Handbook and Catalogue of Deep-Sky Objects Christian B. Luginbuhl and Brian A. Skiff (Cambridge University Press)
This excellent catalog describes more than 2,000 deep-sky objects (in constellations north of declination -50") as seen through 2.4-inch to 12-inch telescopes. The Night Sky Observer's Guide George Robert Kepple and Glen W. Sanner (Willmann-Bell)
This two-volume guide to more than 5,500 double stars, variable stars, and non-stellar objects in 64 constellations visible from the Northern Hemisphere includes descriptions and sketches of objects as seen through 2-inch to 2 2 inch telescopes. However, note that many sights listed are not visible through a small telescope.
Celestial Sampler
f 161
Touring the Universe Through Binoculars Philip S. Harrington (Wiley)
There are more than 1,100 deep-sky objects listed in this guide, and more than 400 are described in some detail. Most of these sights are great for small scopes too! Turn Left at Orion Guy Consolmagno and Dan M. Davis (Cambridge University Press) A fine observing guide to use with your small telescope. It
lists 100 deep-sky sights and includes sketches of how they appear in the eyepiece. GENERAL REFERENCE Nightwatch: A Practical Guide to Viewing the Universe, 3rd Edition Terence Dickinson (Firefly)
This is one of the best introductions to observing the night sky ever written, delightfully touching on a wide range of astronomical pursuits. Starlight Nights Leslie C. Peltier (Sky Publishing)
This charming and inspirational book chronicles Peltier's astronomical adventures that began when he glimpsed the Pleiades through the window of his family's Ohio farmhouse in 1905. The Backyard Astronomer's Guide, Revised Edition Terence Dickinson and Alan Dyer (Firefly)
Here's an in-depth look at the world of amateur astronomy, including the ins and outs of equipment. The Backyard Stargazer Pot Price (Quarry Books)
This friendly, conversational beginner's guide to exploring the night sky includes 46 fun and practical observing projects to get you started.
162
*
Celestial Sampler
WEB SITES OF INTEREST American Association of Variable Star Observers (AAvso: www.aavso.org/aavso
This site contains a wealth of information on variable spars including comparison charts and light curves. Cartes du Ciel (Sky Charts) www.stargazing.net/astropc
This is a software atlas that can be downloaded for free, Internet Amateur Astronomers Catalog (IAAC) www.visualdeepsky.org
Read observations by other amateur astronomers with wide range of observing equipment and different levels of experience; post your own observations here too! Messier45.com http://messier45.com
The site contains information for about 500,000 deep-sky objects and more than 2 million stars. It includes maps and images for every object and has powerful search capabilities.
-
SEDS Students for the Exploration and Development of Space www.seds.org
SEDS hosts many fascinating astronomical Web sites (ir cluding Messier and NGC catalogs)that contain amazin amounts of information. Sky Publishing SkyTonight.com
This site supports Sky & Tekscope magazine ana Ivlgnr MY, the new bimonthly magazine for beginners, and contains observing articles, product information, and how-to tips. The Washington Double Star Catalog http://ad.usno.navy.rnil/wds/wds.htrnl
This catalog contains data for over loo,ooo star systems and is the world's principal database of double- and multip1~star information.
i
Every d e e p - s b object described in the text is included here as it is listed in the table that accompanies each essay Many sights (for example M8 and M63) also have popular names listed as crossreferences (Lagoon Nebula, Sunflower Galaxy). There is n o list of generic entries for each type of d e e p - s b object. Page numbers in boldface refer to photographs o r illustrations. Star o r object designations such as Epsilon Bootis, 61 Cygni, or R Scuti, which contain t h e genitive form of a constellation name, are indexed under t h e constellation, i n these cases Bootes, Cygnus, and Scutum, respectively. Those double stars designated with the Greek letter sigma (C) are listed at the end of the index. ~ ~ l + t s t e ~ e & GaM+ =G ADS 2755,43 ADS 6915, 63 ADS 6921,63 AG 311, 44 Albireo, 11,126 Alcor, 90 Aldebaran, 44 Algol, 34 all-sky maps, 18-31 how to use, 18 latitude, 19 tips, 19 Alpha Persei Association, 34 al- Safi M31, 156 al- SiifiJsCluster see Coathanger Andromeda Galaxy see M31 Andromeda, 142, 156 angular (sky)distance, 13, 13 h s e r , 126 Antares, loo, 102 Apple Core Nebula see M27 Aquarius, 136, 144 Aquila and Scutum, 122
--
164
* Celestial Sampler
arcminutes, definition of, 12 arcseconds, definition of, 12 Arcturus, 94 Arcturus Group, 94 Argelander 31, 116 Argo Navis, 58 Aries, 38 Pi Ari, 39 Auriga, 52 Capella (Alpha Aur), 52 averted vision, 17, 110 Barnard 64, 104, 104 ~ a m a r d85, 116 ~ a m a r d92, 112 ~ a m a r d93, 112 Barnard 106, 121 Bamard 107, 121 Bamard 110, 121 Bamard 111, 121 Bamard 113, 121 ~ a m a r d119a, 121 ~ a m a r d z 2 252 Bamard 259, 104, 104 ~ a m a r dEdward , Emerson, ll5,122 Barnard's Galaxy see NGC 6822 ~ a m a r d ' Loop, s 48, 48 Beehive Star Cluster see M44 Betelgeuse, 46, 51 Big Dipper, 74, 90, 91 finding, 19 pointer stars (to Polaris), 75 see Ursa Major Black Eye Galaxy see M64 Blanco 1, 159 Blanco, Victor, 159 Blinking Planetary see NGC 6826 Blue Snowball see NGC 7662 Bootes, 90, 92, 94 Arcturus (Alpha Boo), 94 Epsilon Boo, 92, 92 Kappa Boo, 91 Iota Boo, 91 Mu Boo, 92,92 Pi Boo, 92,92 Xi Boo, 92,92 Brocchi, Dalmiro F., 126 --
Brocchi's Cluster see Coathanger Burnham 1, 152 Burnham 245,118 b urn ham Jr., Robert, 103 Butterfly Cluster see M6 Caldwell 5 see IC 342 ~aldwell6 see NGC 6543, Caldwell 10 see NGC 663 ~aldwell12 see NGC 6946 ~aldwell13 see NGC 457 Caldwell 14 see Double Cluster ~aldwell15 see NGC 6826 Caldwell 16 see NGC 7243 Caldwell 20 see NGC 7000 Caldwell22 see NGC 7662 Caldwell 28 see NGC 752 ~aldwell30 see NGC 7331 Caldwell 33 see Veil Nebula Caldwell 34 see Veil ~ e b u l a Caldwell 36 see NGC 4559 Caldwell 38 see NGC 4565 Caldwell 39see NGC 2392 Caldwell42 see NGC 7006 Caldwell 55 see NHC 7009 Caldwell 57 see NGC 6822 Caldwell 59 see NGC 3242 Caldwell 63 see Helix Nebula Caldwell64 see NGC 2362 Caldwell65 see NGC 253 Caldwell76 see NGC 6231 Caldwell-Moore, Patrick, 140 California Nebula see NGC 1499 Camelopardalis, 40 Cancer, 62,62 Delta Cnc, 62 Gamma Cnc, 62 Iota Cnc, 62 Canes Venatici, 76 Cor Caroli (Alpha CVnl, .lo Y CVn, 76 Canis Major, 58, 58 Sirius (Alpha CMa), 58, f Capella, 52 Capricorn, Tropic of, 138 Capricornus, 138, 138 Alpha Cap, 138
- - --
-
- -
Beta Cap, 138 Omicron Cap, 139 Pi Cap, 139 Rho Cap, 139 Sigma Cap, 139 carbon star, 51, 72, 102 Cassiopeia, 36, 40, 146, 150, 150, 152, 154 DL Cas, 150 Eta Cas, 152, 154 Iota Cas, 155 Kappa Cas, 150 Phi Cas, 152 Cassiopeia 0B8, 155 Castor, 55 Cat's Eye Nebula see NGC 6543 celestial equator, 12 celestial sphere, 12, 13 Cepheus, 146, 148 Delta Cep, 146 Mu Cep (Herschel's Garnet Star), 147 Cetus, 38 Coathanger, 126, 126 Collinder 34, 40 Collinder 84, 49 Collinder 121, 58 Collinder 285, 90 Collinder 350, 106 Collinder 359, 108 Collinder 360, 117 Collinder 399 see Coathanger Collinder, Per Arne, 49 color index, 51, 89, 92, 102, 120 Coma Berenices 78,80, 84 17 Com, 80 35 Com, 81 Coma Star Cluster see Melotte 111 Copeland, Leland S., 17, 84 C0r Caroh, 76 Corona Borealis, 93 Nu CrB, 93, 93 Sigma CrB, 93, 93 Zeta CrB, 93,93 Crab Nebula see MI Cygnus, 126, 130, 132 16 q g , 132 61 cyg, 131 Albireo (Beta Cyg), 11, 126 Deneb (Alpha Cyg), 130 Cyg, 133 * h e s t , Heinrich, 44 dark adaptation, 14 declination, 12 Del~hinus, 134, 1~ Gamma Del, 135
Deneb, 130 dew, protection against, 14, 15 Dog Star see Sirius Dolidze 27, 107 Dolidze-DimSelejSvili1, 39 Dolidze-DimSelejSvili9, 99 Double Cluster, 34, 35, 36 Double-Double, 124 double stars description of, 11 designation (C), 86 position angle, 93 Draco, 102 39 Dra, 102 Nu Dra, 102 Omicron Dra, 102 Psi Dra, 103 UX Dra, 102 Dragonfly Cluster see NGC 457 Dreyer, John L. E., 140 Dubhe, 75 Dumbbell Nebula see M27 Eagle Nebula see Mi6 ecliptic, 19 Engagement Ring, 88 Eskimo Nebula see NGC 2392 ET Cluster see NGC 457 False Comet, 100 field of view (apparent, true), -13 finderscope, 13, 14 erect, inverted, mirror-image view!! 1 A Fish's Mouth Nebula, 46 Flame Nebula see NGC 2024 Frommert, Hartmut, 91 galaxies, description of, n grand-design spiral, 79 Gemini, 54 Castor (Alpha Gem), 55 Delta Gem, 55 Pollux, 54 W Gem, 55 Ghost of Jupiter see NGC 3242 Great Cluster in Hercules see Mi3 Great Pegasus Cluster see Mi5 Great Rift, 122 Greek alphabet, 19 H N 6, 117 H N 40, 117 h975, 143 h3752, 51 h3759, 50 Halley, Edmond, 98, 122 Harvard 20, 134, 134 Helix Nebula, 144, 144 Hercules, 98 ---
-
Mu Her, 99 Herschel VI 50, 120 Herschel, Caroline, 150, 158 Herschel, John, 143 Herschel, William, 44, 70, 72 Herschel's Garnet Star, 147 Hevelius, Johannes, 126,140 Hind's Crimson Star, 51 Hipparchus, 14 Hodierna, Giovanni, 52 Hogg, Helen Sawyer, 69, 107 Hough 197, 143 Hourglass Nebula see NGC 6523 Houston, Walter Scott, 41, 132 Howe 43, 119 Huggins, William, 103 Hyades, 44 Hydra, 57, 72 V Hya, 72 I c 342,40, 41 IC 418, 51 I c 1318, 133 I c 1396, 146, 147 I c 1434, 141 I c 1590, 152 IC 1805, 36, 37 I c 1848,40,40 I c 4655, 108 I c 4703, 112, 113 I c 4756, 108, 109 Index Catalogues (IC), 141 bserstedt B - & Q . Z~L James, Thomas, 62 Kemble 2, 102 Kemble, Lucian J., 41, 102 Kemble's Cascade, 41 King 14, 150, 151 King 19, 149 King, Ivan R., 149 Kochab, 88 La Superba, 76 Lacaille, Nicolas-Louis de, 158 Lacerta, 140, 140, 142 SS Lac, 141 Lagoon Nebula see M8 LDS 2246,44 Le Gentil 3, 130 Leo, 66, 67,68, 70 Gamma Leo, 70 R Leo, 71 Regulus (Alpha Leo), 66 Sickle of, 66, 70 Leo I Dwarf Galaxy, 70, 71 Leo I Group, 68 Leo Triplet, 66 Lepus, 50, 50 -
Gamma Lep, 50 R Lep (Hind's Crimson Star), 51 light pollution, 15, 15 light-year, definition of, 14 Little Dipper, 88, 88 see Ursa Minor Little Dumbbell see M76 Little Gem see NGC 6818 L O C ~Group, 156 Lorenzin, Tom, l53 Lyra, 124, 124 Beta Lyr, 125 Delta Lyr, 124 Double-Double (Epsilon Lyr), 124 Gamma Lyr, 125 Kappa Lyr, 125 Lambda Lyr, 125 Vega (Alpha Lyr), 124 Zeta Lyr, 124 MI (Crab Nebula), 4 4 4 5 M2, 136, 137 M3, 76, 7 6 9 4 , 94 M4, 100 M5, 86, 87 M6 (Butterfly Cluster), 101 M7, 101 M8 (Lagoon Nebula), 110, 110, 116, 116 M9, 104,104 M10, 86, 87 M11 (Wild Duck Cluster), 120, 120,122 M12, 86,87 Mi3 (Great Cluster in Hercules), 98,98 M14, 106, 106 M15 (Great Pegasus Cluster), 136, 136 M16 (Eagle Nebula), 112, 113 M17 (Swan, Omega Nebula), 113 M18, 112 Ml9, 104, 105 M20 (Trifid Nebula), 116, 116 M21, 117 M22, 111,118, 118 M23, 111 M% (Small Sagittarius Star Cloud), 112 M25, 111 M26, 123 M27 (Dumbbell, Apple Core Nebula), 126, 127 M28, 118, 118 /
M29, 131, 133 M30, 138,139 M31 (Andromeda Galaxy), 156, 156 M32, 156
166
* Celestial Sampler
M33 (Pinwheel Galaxy), 156 M34, 34 M35, 54, 54 M36, 52, 53 M37, 52, 53 M38, 52, 52 M39, 130 M41, 58, 59 M42 (Orion Nebula), 16,46, 46 M43,46, 47 M44 (Praesepe, Beehive Cluster), 62,63 M45 (~leiades), 42,42 M46, 56, 57,60, 60 M47, 56, 57, 60, 60 M48, 57, 72 M50, 56,56 M51 (Whirlpool Galaxy), 76, 77 M52, 146, 147 M53,80 M54, 118, 119 M55, 114, 114 M56, 125 M57 (RingNebula), 124, 125 M58, 82,83 M59,82,83 M60, 82,82 M62, 105 M63 (Sunflower Galaxy), 77 M64 (Black Eye Galaxy), 80,81 M65,66,66 M66,66,66 M67,63 M68, 73 M69, 118, 119 M70, 118,119 M71,174, W M72, 137 M73, 137 M74 (phantom Galaxy), 38, 38 M75, 114 M76 (Little Dumbbell), 36, 36 M77, 38 M78,48 M79, 50 M80, 100 M81, 74, 74 M82, 74, 74 M83, 72,73 M84,79,84 M85, 79, 81 M86,79,84 M87,83 M89,83 M90,82,83 M92,98,99
M93, 59, 59 M95,68,68 M96,68,68 M97 (Owl Nebula), 74, 75 M98, 78, 78 M99, 78, 78 M1OO1 79, 79 MlOl, 90,90 M102, 91 M103, 154, 154 M105,69 M107, 106, 107 Mlo8, 7475 Ml09, 74, 75 M110, 156 Maffei 1Group, 41 magdication and contrast, 16 calculation, 13 maximum useful, 16 magnitude definition of, 14 integrated, 38 Maia Nebula see NGC 1432 Maraldi, Jean-Dominique, 136 Markarian 6, 37 Markarian 50, 149 Markarian, Benjamin E., 84 Markarianls Chain, l2,84 MCchain, Pierre, 69, 91, 107 Melotte 20 see Alpha Persei Association Melotte 71, 61 Melotte 111, 80 Merak, 74 Merope Nebula see NGC 1435 Messier, Charles, 45, 60, 66, 72, 100, 115, 140, 156 Milky Way in Cassiopeia, 146, 150, 150 in Cepheus, 148 in Cygnus, 130, 140 in Lacerta, 140, 140 in Ophiuchus, 104 in Sagittarius, 10, 110, 110, 112, I* in Scutum, 120, 122, 122 in winter, 56 Perseus Arm, 35, 155 Sagittarius Arm, loO,ll2,122 Mini-Cas see Kemble '7Mini-Coathanger, 89 Mirfak, 34 Mizar, 90, 91 Monoceros 56 Moore, Patrick see ~ a l d w e l l - M o o ~ ~ mounts, types of, 14
nebulae, description of, n New General Catalogue (NGC), 140 NGC 129, 150, 151 NGC U3, 150, 151 NGC 146, 150, 151 NGC 205 see Milo NGC 225, 150 NGC 253, 158, 158 NGC 281, 152, 152 NGC 288, 158, 158 NGC 381, 151 NGC 436, 152, 153 NGC 457 (Dragonfly, ET, Owl Cluster), 153, 153, 154 NGC 604, 157 NGC 650 see M76 NGC 651 see M76 NGC 654, 155, 155 NGC 659, 155 NGC 663, 154 NGC 744, 153 NGC 752, 157 NGC 869 see Double Cluster NGC 884 see Double Cluster NGC 896, 37 NGC 1027, 37 NGC 1055, 38, 39 NGC 1432 (Maia Nebula), 43 NGC 1435 (Merope Nebula), 42,43 NGC 1499 (California Nebula), 35 NGC 1501, 41 NGC 1502, 41 NGC 1528, 34, 34 NGC 1545, 35 NGC 1647,44 NGC 1746,44 NGC 1750, 44 NGC 1758, 44 NGC 1907, 52, 52 NGC 1977,46,47 NGC 1981, 46,47 NGC 2017, 50 NGC 20% (Flame Nebula), 48 NGC 2071,48 NGC 2112, 48 NGC 2158, 54, 54 NGC 2169 (37 Cluster), 48,49 NGC 2174, 49 NGC 2175, 49 NGC 2194,49 NGc 2266, 54, 54 NGC 2354, 58 NGC 2362 (Tau Canis Majoris Cluster), 59, 59 NGc 2392 (Eskimo Nebula), 55, 55 NGC 2423, 56, 57, 60, 61,
Index NGC 2438, 57, 60,46 NGC 2440,61 NGC 2548 see M48 NGC 2903, 70, 70 NGC 2905, 70 NGC 3242 (Ghost of Jupiter), 72, 72 NGC 3377, 69 NGC 3384, 69 NGC 3389,69 NGC 3412,69 NGC 3489, 69 NGC 3628,66,66 NGC 4387, 84 NGC 4388,84 NGC 4394,81 NGC 4402, 84 NGC 4413,84 NGC 4425,84 NGC 4435, 84, 84 NGC 4438,84, 84 NGC 4458,85 NGC 4461, 85 NGC 4473,85 NGC 4477, 85 NGC 4478,83 NGC 4479, 85 NGC 4559, 81 NGC 4565,80,81 NGC 4638, 82, 83 NGC 4647,82,83 NGC 4754, 82, 82 NGC 4762,82,82 NGC 5053,80 NGC 5195, 76,77 NGC 5466,94 NGC 5529,95 NGC 5557, 95 NGC 5676,95 NGC 5689,95 NGC 5866,90,91 NGC 6207,98,98 NGC 6210 (Turtle Nebula), 99 NGC 6231, 101 NGC 6284, 104 NGC 6293, 104, 105 NGC 6342, 104, 104 NGC 6356, 104, 104 NGC 6366, 106, 106 NGC 6503, 102, 103 NGC 6514, 116 NGC 6523 (Hourglass Nebula), 116 NGC 6530, 116 NGC 6543 (Cat's Eye Nebula), 102, 103 NGC 6572, 108, 109 NGC 6624, 118, 118 NGC 6633, 108, 109
NGC 6664, 122 NGC 6712, 123 NGC 6774, 115 NGC 6811, 132 NGC 6818 (Little Gem), 115 NGC 6822 (Barnard's Galaxy), 114, 115 NGC 6826 (Blinking Planetary), 131, 132 NGC 6866, 132 NGC 6910, 132 NGC 6939, 148, 148 NGC 6940, 127 NGC 6946, 148, 148 NGC 6960 see Veil Nebula NGC 6992 see Veil Nebula NGC 6995 see Veil Nebula NGC 7000 (North America Nebula), 130, UO NGC 7006, 135 NGC 7009 (Saturn Nebula), 137 NGC 7160, 148 NGC 7209, 140, I40 NGC 7235, 148 NGC 7243, 140, 141 NGC 7293 see Helix Nebula NGC 7331, 142, 143
NGC 7380, 149 NGC 7510, 149 NGC 7640, 142 NGC 7662 (Blue Snowball), 142, 142 NGC 7788, 150, 151 NGC 7789, 146, 147 NGC 7790, 150, 151 NGC 7793, 158, 159 North America Nebula see NGC 7000 north celestial pole, 12 North Star see Polaris O'Meara, Stephen James, 80, 153 observing log, 16,17 Olcott, William vier, 35 Omega Nebula see Mi7 Ophiuchus, 86, 104, 106, 108 36 Oph, 105 61 Oph, 106 67 Oph, 108 70 Oph, 108 V Oph, 107 V Oph chart, 106 Orion, 46,48 Belt, 46 Betelgeuse (Alpha On), 46, 51 Iota Ori, 47 Nebula (M42), 16, 46, 46 Rigel, 46, 51 Sword, 46 Trapezium, 46,47
Celestial Sampler
* 167
Sculptor Group, 159 Scutum, 120, 122, 122 EV sct, 122 R Sct, 121 Scutum Star Cloud, 120, 122, 123 seeing, 15, 15 Sei 350, 52 Serpens 5 Ser, 86, 86 Serpens Caput, 86 Serpens Cauda, 108 Seven Sisters see Pleiades, M45 Seyfert galaxy, 39 Sharpless 2-157, 149 SKJ 251,106 Sickle (of Leo), 66, 70 Silver Coin Galaxy see NGC 253 Sirius, 58, 58 Small Sagittarius Star Cloud see M24 Smyth, William H., 120 spectral type, 92 starburst galaxy, 67, 75, 159 star charts, how to use, 12 star clusters, description of, 11 star-hopping, 12 Star Queen Nebula see MI6 Stein 368, 37 Stephenson 1,125 Stock 2, 36 Stock 4, 153 Stock 12, 146 Stock 23, 40 Stock, Jurgen, 153 Struve, F. G Wilhelm, 86 ~ P58 , Sunflower Galaxy see M63 Puppis, 56, 58, 60 supernova Regulus, 66 remnant, 45 Rigel, 46, 51 Type Ia, 68 right ascension, 12 Swan Nebula see M17 Ring Nebula see M57 Tau Canis Majoris Cluster see NGC Ruprecht 173, 133 Taurus Poniatovii, 108 Sagitta, 134, 134 Taurus, 42,44 Sagittarius Dwarf Elliptical Galaxy, 119 75 Tau, 44 Sagittarius, 100, 110,112, 114, 116, 118 Aldebaran (Alpha Tau), 44 Teapot, 110, 114 Hyades, 44 S698, 117 Teapot, 110, 114 u Sgr, 111 Toadstool, 135 SAO 76206,43 Transparency, 15 Saturn Nebula see NGC 7009 Trapezium, 46, 47 Scorpius, 100, 100 Triangulum, 156 Antares (Alpha Sco), 100,102 Trifid Nebula see M20 Beta Sco, 100 Trumpler 3, 41 BM Sco, lo1 Trumpler 24, 101 Nu Sco, 100 Turtle Nebula see NGC 6210 Zeta Sco, 100 Ursa Major, 74, 90 Sculptor, 158 Alcor, 90 Delta Scl, 159
Owl Cluster see NGC 457 Owl Nebula see M97 oxygen III filter (0III), 145 Pazmino's Cluster, 40 Pease 1,136 Pegasus, U6, 136,142 Perseus, 34, 36, 153 Algol, 34 Eta Per, 35 Mirfak (AIpha Per), 34 Phantom Galaxy see M74 Piazzi 6, 119 Piazzi, Giuseppe, 131 Picot 1, 94 Picot, Fulbert, 94 pinwheel Galaxy see M33, M99, Mlol Pisces, 38 Planicus, Petrus, 40 Pleiades (M45),42, 42 Atlas, 43 Maia Nebula, 43 Merope Nebula, 42, 43 Pleione, 43 Sterope, 43 Taygeta, 43 Poczobut, Martin, 108 Polaris (pole star), 74,88 pointer stars to, 75 Pollux, 54 power see magmfication Praesepe see M44 precession, 88 Procyon, 56
Big Dipper, 74, 90, 91 Dubhe (Alpha UMa), 74, 75 Merak, 74 Mizar, 90, 91 Ursa Minor, 88 11UMi, 89 19 UMi, 89 20 UMi, 89 24 UMi, 89 Delta UMi, 89 Epsilon UMi, 89 Eta UMi, 89 Gamma UMi, 89 Kochab, 88 Polaris (Alpha UMi), 88 Theta UMi, 89 Zeta UMi, 89 V42,86 variable stars, description of, 11 Vega, 124 Veil Nebula, 132, 133 Vindemiatrix (EpsilonVir), 82 Virgo, 78, 82, 84 Virgo Galaxy Cluster, 78 Vulpecula, 126 Anser (AlphaVul), 126 Whirlpool Galaxy see M51 Whitman, Alan, 100 wiggle factor, 17 Wild Duck Cluster see M11 zenith, definition of, 13 0 2 134, 54 C I 10,44 2131, 154 U50,43 2737, 52 x745, 47 2747, 47 21120, 57 21121, 57 C1689,82 C1825, 92, 92 21835,92,92 C1930, 86, 86 C1985,86,86 ~2031,86,86 X2216, 109 C2375, 109 Z2391, 120 22521, 127 C2703, 135 C2725, 135 C2816, 147 22819, 147 22890, 140 c (sigma)double-star designation! 86
INTRODUCTION
p l o Akira Fujii; p l l Richard Tresch Fienberg; p i 2 [top] Steve Cannistra, [bottom] Slzy & Telescope; p13 S k y & Telescope (x2); p14 Dennis di Cicco; p i 5 [top] Alan Adler, [bottoml Dennis di Cicco(x2); p i 6 [top left] Alan Dyer, [top right] Craig Michael Utter, [bottom] Becky Ramotowski; p17 David Kone. HOW TO USE THE ALL-SKY STAR MAPS
p l 8 Sky & Telescope (x2);p21-30 S k y & Telescope.
All finder charts in Chapters 1 through 4 inclusive: Sky & Telescope. CHAPTER 1
p34 [top] Akira Fujii, [bottom] Martin C. Germano; p36 [top] William C. McLaughlin, [bottom] Jon A. Kolb; p38 [topl Kim Zussman, [bottom] Robert Gendler; p40 [top] Bobby Middleton, [bottom] Robert Gendler; p42 [top] Akira Fujii, [bottom] Bob & Janice Fera; p44 Russell Croman; p46 Steve Cannistra; p47 Lick Observatory; p48 [topl George R. Viscome, [bottom] Akira Fujii; p50 Akira Fujii; p52 Lee C. Coombs; p53 Preston Scott Justis (x2);p54 [top] Till Crednerl Sven Kohle, [bottom] Akira Fujii; p55 Sean Walker; p56 [top] Martin C. Germano, [bottom] Chris Cook; p58 A h r a Fujii, [inset] R.B. Milton; p59 Martin C. Germano (x3); p60 George R. Viscome (x2); p62 Akira Fujii; p63 Akira Fujii. CHAPTER 2
p66 Robert Gendler; p67 Akira Fujii; p68 [top right] Bill & Sue Galloway, Adam Block, NOAO/AURA/NSF, [top left] Dan Stotz, Mike Ford, Adam Block, NOAO/ A U m S F , [bottom] George R. Viscome; p70 [top] STScI/Digitized Sky Survey, [bottoml Bobby Middleton; p72 [top] Akira Fujii, [bottom] Richard D. Jacobs; p74 [top] Akira Fujii, [bottom left] h a Fujii, [bottom right] GCrard Therin; p75 Sue French; p76 Akira Fujii h2), [b&w insets] Sue French (x2); p78 [top] George R. Viscome, [bottom] Martin C. Germano; p79 Martin C. Germano; p80 Bob & Janice Fera (x2);p 8 l Sue hench; p82 [upper left] Martin C. Germano, [upper dght] John Mirtle, [lower left] John Mirtle, [lower right] Martin C. Germano; p84 Adam Block, NOAO/ AUWNSF; p86 Sissy Haas (x3), [bottom] Akira Fujii;
p87 Joseph Liu; p88 Akira Fujii; p90 [top] Preston Scott Justis, [bottom] Akira Fujii; p 9 l Akira Fujii, [inset] Dennis di Cicco; p92 Sky & Telescope (x6); p93 Sky & Telescope (x4);p94 George R. Viscome. CHAPTER 3
p98 [top] Bob & Janice Fera, [bottom] Preston Scott Justis; p99 Martin C. Germano; p l o o Akira Fujii; p102 Adam Block, NOAO/AURA/NSF (x2); p104 [top] Palomar Observatory Sky Survey, [top, inset] Tan Wei Leong, [bottom] Palomar Observatory Sky Survey; p l 0 6 (top] AAVSO, [bottom left] Evered Kreimer, [bottom middle] Evered Kreimer, [bottom right] Martin C. Germano; p108 [top] Digitized Sky Survey, [bottom] Akira Fujii; pllo [top] Sue French, [bottom] Akira Fujii; pill Sue French; p112 [top] Sue French, [bottom] Luke Dodd; pl13 Jose Torres; pi14 [top] Martin C. Germano, [bottom] Lee C. Coombs; p l l 6 Akira Fujii; p118 [upper left] Martin C. Germano, [upper right] Lee C. Coombs, [middle left] Digitized Sky Survey, courtesy U.K. Schmidt Telescope Unit and NASA/ AURA/STScI, [middle right] Evered Kreimer, [lower left and right] Evered Kreimer; p120 &ra Fujii, [inset] Alan MacRobert; p122 Akira Fujii; p123 Akira Fujii; p124 Akira Fujii (x2);p126 [top left] Ronald P. Manley, [top right] Sue French, [bottom] Michael Stecker.
,
CHAPTER 4
p130 [topl Sue French, [bottom] Ben Gendre; p ~ 2 [top] Sue French, [bottom] Bobby Middleton; pi34 [left] Akira Fujii, [right] Martin C. Germano; pi36 [top left] Adriano Defreitas, [top right] Bob & Janice Fera, [bottom] Akira Fujii; pl38 Akira Fujii (x2); p140 [top] Martin C. Gennano, [bottom] Akira Fujii; p141 Martin C. Germano; p142 [top] Chip Levinson, Adam Block, NOAO/AURA/NSF, [bottom] William C. McLaughlin; p144 [top] Bill Ferris, [bottoml Gary L. Stevens; p146 &ra Fujii, [b&w inset] Sue French; p147 Akira Fujii (x2); p148 Jerry Lodripss; p150 ~ k i r a Fujii; p151 George R. Viscome (x3); p152 [top] George R. Viscome, [bottom] Sean Walker; pl53 George R. Viscome; p154 [top] Preston Scott Justis, [bottom] Akira Fujii; p155 Preston Scott Justis; p156 Robert Gendler; p158 [top left] ~effreyL. Jones, [top right] Eugene A. ~ a r l a n [bottom] , Jerry Lodriguss.
Celestial Sampler
* 169
I
. a o u t the Author The July 1999 issue of Sky & Telescope marked the debut of Small-Scope Sampler, a column by Sue French devoted to exploring the wonders of the deep sky with a small telescope. Celestial Sampler is a compilation of her first 60 columns, arranged by month. Each essay includes: It's unusual to find an accomplished stargazer who not only knows the sky intimately but also has a thorough command of the underlying astrophysics. Sue French has gained a worldwide following in both capacities. In the mid-1990s her writing skills came to the attention of the editors at Sky & Telescope magazine, and soon her observing column Small-Scope Sampler - began appearing on a monthly basis. She also writes a star-hopping column for S&T's sister publication, Night Sky. This self-proclaimed "Queen of the Darkness" currently owns seven telescopes, ranging in aperture from 4 to 15 inches. And when the Moon or clouds interfere, she likes to settle in for the night with some good science-fiction reading.
bonus: FREE issue offer of Sky & Telescope see inside for details
-
w
descriptions of double and variable stars, star clusters, nebulae, and galaxies
w
some basic science behind many of these objects
w
photographs by amateur astronomers
w
a tabular listing of the deep-sky sights a finder chart
. w
challenge objects that encourage observers to tes
the limits of their equipment and skills Deep-sky observing is an engaging pastime, no matter what size your telescope. Whether you're a novice skywatcher wondering what to look at tonight, or an experienced stargazer seeking new or overlooked targets, let Celestial Sampler be your guide to many wellknown, and obscure, treasures of the night sky.
"Sue French offers a rare combination: an encyclopedic knowledge of the night sky, exceptional observing skills, and a transcendent ability to convey the excitement of stargazing through the written word. It's no surprise that she's one of today's most admired astronomy writers." RICHARDTRESCH FIENBERG
Editor in Chief Sky & Telescope magazine
Cover image: Helix Nebula by Gary L. Stevens Inset images: Pleiades by Akira Fujii Andromeda Galaxy by Robert Gendler
1
I S B N 1-931559-28-7
I >kyTonight.com
Skv Publishing, 49 Bay State Rd., Cambridge, MA 02138
I
i i
I
