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LittleDipper
a
b
i
b
e
9h
7h
5h
3h
1h
21h19h
17h
15h
13h
23h
11h
M56
M52
M76
M103
M29
M39
M57
M13 M92
M112
M111
URSAMINOR
KochabPolaris
DRACO
Thuban
Etamin
CEPHEUS
CAMELOPARDALIS
LACERTA
CASSIOPEIA
ANDROMEDA
Vega
CYGNUS
VULPECULA
Caph
Deneb
Albireo
Alpheratz
Scheat
GreatSquare
M31M32
M110 Mirach
PERSEUSMirphak
Capella
AURIGA
LYRA
Keystone
M63
M94
M51
M101
M102
M40
Alioth
Mizar
Alkaid
Megrez
CANESVENATICI
Big Dipper
PEGASUS
MilkyWay
c
b
a
f
i b a
c
d
e
c
u
51
j
a
k
i
h
gf
d
nb
c
d
e
f
g
a
d
c
e
b
b
dp
bl
a
a
c
i
p
NorthernCross
a
ea
b
c
g
ic
a
gs
d
j
a
a
b
Alnath
e
M92
PEGASUS
Alpheratz Scheat
PISCES
AQUARIUS
SCULPTOR
Fomalhaut
PISCIS AUSTRINUS
GRUS
MICROSCOPIUM
M72
M30
M73
M75CAPRICORNUS
DabihDenebAlgedi
Enif
M2
M15DELPHINUS
EQUULEUS
LACERTAM29
CYGNUS
AQUILA
Altair
M55
M22
M54
M69M70
M23M24M17
M25
M7
M16
M21
CORONAAUSTRALIS
Shaula
KausAustralis
SAGITTARIUS
NunkiM28
M18
M26
M11
SERPENS(CAUDA)
SCUTUM
M57
Vega
LYRA M13
M56
Albireo
M71
SAGITTA
VULPECULAM27Great Square
MilkyW ay
ANDROMEDA
xi h
c
jk
b
c
a b
a
d
b
l
p
nf
h
e
u
w
x
d
k
j
gf
c
a
b
m
e
a
de
bac
d
e
b
a
c b
e
a
a
c
a
b
c
d c i
f
x
bs
h
a
i
e
a
b
c
p
g
h
g
ji
l
g
e
cf
s ru
k
d
no
p
c
a
b
g
h
b
f
21h
22h23h
0h1h 20h
19h
18h
17h
k t
gk
12
Algedi
s
m
Circlet
e
c
HERCULES
e
n
d
fe
M31M32 M110
c
b
d
36
QCHART
21Hour
NORT
HRCHART
SOUTH
21Hour
M9
M19
M62
M8M22
M54
M69M70 M6
M23M24
M17
M25
M7
M26
M16
M20M21
KausAustralis
SAGITTARIUS
SERPENS(CAUDA)
Sabik
Nunki
SCUTUM
M28
M18
CORONA AUSTRALIS SCORPIUS
Shaula
OPHIUCHUS
MilkyWay
18h
19h 17h
Ascella
KausBorealis
KausMedia
Alnasl
Lesath
41 p
39 o37 n
36 f
40 s
44 r 27 u
22 k
19 d
20 e
10 c
g
35 k
34 t
35 k
24
13 l21
74
35 g
53 m
55 n
56 o
64 m
c
afd
e
57 l
42 h
39 o
44
36
43
45
3
26 e
SCORPIUS
1° Circle
M66M65
M59M60 M58M89
M90
M87
Denebola
M49
M84
M99M98
M100
M88M91
M86
M85
M61
M64
M3
LEO
COMABERENICES
M53
VIRGO
Vindemiatrix
Chertan
Zosma
94 b
35
47 e
33
32
29
41
30 q27
20
6
25
24
11
27
33/3236
26 20
12
5
42 a
43 b
41
3130
15 c
14
37
16
1713
12
7
23
21
18
13h 12h
70 h
68 d
78 i
43 d
3
9 o
8 p
16
31
1° Circle
Order of Brightnessof Virgo Galaxy Clusterstarting with Brightest
M64, M49, (M104), M87, M60, M85,M86, M84, M88, M61, M58, M59,M89, M90, M99, M100, M98, M91
SCHART
SAGITTA
RIUSARE
ATCHART
VIRGOGALA
XYCLU
STERAREA
VCHART
VIRGOCLU
STERMIRRORREVERSEDFO
R90°DIAGONALUSERS
UCHART
VIRG
OGALA
XYCLUST
ERDETAIL
30 q
2720
33
36
33
27
25
24
11
3
6
29
28
34
41
12
9 o
32
3526 20
5
47 e
32
2
13h
12h
M59M60M58
M89
M90
M87M84
M99
M98
M100
M88M91
M86
M85
M49
M64
VIRGO
1° Circles
Vindemiatrix
To Denebola
30 q
2720
33
36
33
27
25
24
11
3
6
29
28
34
41
12
9 o
32
352620
5
47 e
32
2 MIRROR REVERSED
13h
12h M59 M60
M58
M89
M90
M87M84
M99
M98
M100
M88M91
M86
M85
M49
M64
VIRGO
1° Circles
Vindemiatrix
To Denebola
TheMessier Objects
Above left. The first page of the third and final edition of Messier’s catalogue as it appearsin the 1784 Connaissance des Temps. Above. Translation of the first page. This is theonly page of commentary in the final catalogue (which totals 51 pages). Immediately fol-lowing the last page of the catalogue is a two-page article where Messier lists negativefinds searching for deep sky objects reported by other astronomers. Next page. First twocatalogue pages from the final catalogue. Compared to the first edition of the catalogue(see page 333), this final edition numbers the objects and has longer descriptions.Messier’s descriptions in this book were translated from this final catalogue. Images cour-tesy of Professor Owen Gingerich of the Harvard-Smithsonian Center for Astrophysics.
C A T A L O G U EOF THE
NEBULAE AND STAR CLUSTERS
Observed in Paris, by Mr. Messier, at the Navy Observatory,Hotel Clugni, on Rue des Mathurins.
r. Messier has most carefully observed the Nebulae & Star Clusters that can be seen over Paris’horizon; he determined their right ascension and their declination, and provided their diameters,along with detailed information on each of them: a publication that was lacking in the field ofAstronomy.
He also goes into detail about the research he conducted on various nebulae whose discoveriesare credited to several astronomers, but that he unsuccessfully found.
Mr. Messier’s Catalogue of Nebulae & Star Clusters appeared in the volume of the Academy ofSciences, year 1771, page 435. He included at the end of his Report a very carefully traced draw-ing of the beautiful Orion Sword Nebula, with the stars it contains. This drawing will make it possi-ble to check if, with the passing of time, it undergoes any changes. If you compared this drawing nowwith those of Messrs. Huygens, Picard, de Mairan & le Gentil, you would be surprised to find that ithad been changed in such a way that it would be hard to believe it was the same nebula, based onlyon its shape. These drawings, rendered by Mr. le Gentil, can be seen in the 1759 volume of the Acad-emy, page 470, figure XXI.
In regards to Mr. Messier’s Catalogue presented here, we have added a large number of nebulae& star clusters he has discovered since his Report was printed & he has been reporting to us.
For each nebula, Mr. Messier assigned a number that can also be found on the following pages,along with details on each of the nebulae he observed.
M
107
Description of Messier ObjectsThese are my descriptions based on using a4-inch diameter refractor in fairly dark locations.I kept them short in order to leave room for ob-servers to form their own impressions. Remember,objects can look quite different depending onfactors like atmospheric conditions, light pollutionand altitude in the sky.
Locating IndexI chose to use the short and straightforwardscale of Easy, Fairly Easy, Slightly Challenging,Challenging and Difficult. Any scale is relative,but I think this one will be intuitive after you havefound several objects.
Identifying /Observing IndexUses the same scale as the Locating Index.
PhotographsEach photograph is a 20-minute exposure on 400speed negative film through a 4-inch refractor at alocation with reasonably dark skies. The photo-graphs are all at the same scale to provide conven-ient comparisons.
The photographs show the objects as if viewedwith approximately 15x to 20x magnification heldat normal reading distance.
There is an arc degree scale (see Glossary)along the left side of the photographs for measure-ments and a directional indicator pointing to celes-tial north.
106
Original Messier DescriptionsThese descriptions were taken from the FrenchConnaissance des Temps (translated as Knowl-edge of the Times) 1784 edition. This was thethird and last time Messier published his cata-logue, with more entries than ever, totaling 103.
Messier’s descriptions were translated byIsabelle Houthakker whom I have been fortunateto work with on several projects. She is an excep-tional French translator because of her thorough-ness and attention to detail. For these descrip-tions, I specifically asked her to keep the “flavor”of the printed text in Connaissance des Temps.This includes keeping any abbreviations, italics,symbols (like ampersands, that is, the “&”) andcontractions so that the translated English mimicsthe original French as closely as possible.
My notes provide additional informationabout names and facts in the descriptions.
NGC SummariesThe NGC Descriptions were taken from NGC2000.0, edited by Roger W. Sinnott and publishedby Sky Publishing Corporation. The NGC descrip-tions that I present are an “expansion” of theactual descriptions which consist of a seriesof abbreviations and modifiers. For example,the actual NGC description for M1 reads: vB, vL,E 135°±, vglbM, r; = M1. You can decipher this by
reading my expansion on page 108. Dreyer usedapproximately 125 abbreviations and modifiers.Keep in mind that Dreyer’s descriptions date toobservations prior to 1900.
LocationsThe constellations and their three-letter abbrevia-tion are noted along with coordinates calculatedfor the year 2000. Remember, none of these ob-jects are actually “in” these constellations, butrather lie in their direction.
Observation PeriodsThese are the months when these objects are visiblein the sky at around 8 p.m. and 4 a.m. StandardTime for most people in North America. Add onehour for Daylight Saving Time from April to October.
FactsFacts vary widely from source to source. Mysources were: Sky Atlas 2000.0 Companion, NGC2000.0, Sky & Telescope’s Messier Card, TheMessier Objects by Stephen James O’Meara, Ob-server's Handbook 2004 and articles in Sky & Tel-escope magazine. The physical dimensions of ob-jects were calculated by using simple trigonome-try based on their distances. Also see the defini-tions of Galaxy and Globular Cluster in the Glos-sary for supporting information on these objects.
Legend for Messier Objects Catalo
gueLeg
end
Typical Eyepiece Fields of View (FOV)Scaled to the Photographs of the
Messier Objects
1° FOVcan be obtained
with an 8-inch SCT usinga 40mm Plossl eyepiece.Any Plossl that provides
a telescope magnificationof about 50x will also
provide a 1° FOV.
Using the same scale as thephotos, here is the largest thatJupiter will appear in the sky— measuring 50 arc secondsin diameter (50").
2° FOV is the samearea that the Moon and
Sun cover in the skyand can be obtainedwith an 8-inch SCT
using a 20mmPlossl eyepiece.
This circle measures1ss inches or
35mm in diameter.
This circle measures2ww inches or
70mm in diameter.
For easy comparison, all photographs are shown at the same scale, measuring 2.3° x 1.3°.
TO LOCATERefer to
Star ChartsB,F
& H
M1
NGC Summary by J.L.E. Dreyer, circa 1888NGC Number: 1952Mag: 8.4 Size: 6'NGC Description: Very bright, verylarge, extended along position angleof about 135°, very gradually becomesa little brighter in the middle, mottled.
Location Constellation: Taurus (Tau)
Year 2000 CoordinatesRA: 5h 34.5mDec: +22° 01'
Observation PeriodsEvenings 8 p.m. : November to AprilMornings 4 a.m. : August to January
M1 Crab Nebula � Supernova Remnant Description of M1 using a 4-inch refractor at 48xShaped like a candle flame. Withaverted vision, it shows a brightercenter that fades outward on oppo-site sides. Similar in size to M78 but brighter and more extended.
Locating Index: Easy because it is about 1°from the southern 22 magnitude “horn” star, f Tauri, “toward” the star Alnath.Identifying/Observing Index: Easy or difficultdepending on the darkness of your skies be-cause it gets washed out easily by light pollu-tion. I grew up in Milwaukee and was unableto see this gem with a 10-inch telescope fromour northside home.
ARCSCALE
10'
20'
5'
15'
25'
1/2°
0'
N
1°
3/4°
The Crab Nebula caught Messier’s attention because its shape resembles some comets. It wasthis nebula that inspired him to start cataloguing deep sky objects.
Original Messier Descriptionfrom the 1784 edition of Connaissance des Temps
Observed 1758. Sept. 12
Nebula above the southern horn of Taurus, contains no stars; it’s a whitishlight, elongated in the shape of a candle’sflame, discovered while observing theComet of 1758. See the Map of thisComet. Mém. Acad., year 1759, page 188; observed by Dr. Bévis in about 1731. It’s reported on the English Celestial Atlas.
Author’s Notes: Messier had correspondence with Dr. John Bévis(1695–1771) from England, a physician and amateur astronomerwhose star atlas Uranographia Britannica was published posthu-mously. This atlas indicated M1, M11, M13, M22, M31 and M35.
Mém. Acad. refers to Mémoires de l’Académie des Sciences(Reports of the Academy of Sciences).
FactsName: Crab NebulaType of Object: Supernova remnantMagnitude: 8Distance: 4,000 lyPhysical Size: 7 ly x 4.6 lyArc Degree Size in Sky: 6' x 4' Other: The explosion which created thisremnant occurred on July 4, 1054 andwas recorded by the Chinese, Arabs andJapanese. It was visible for about 22months, and for a while, could be seenduring the day. The Crab Nebula is expanding at the rate of about 990 miles/second. The last supernova explosion inour galaxy occurred in 1604.
109108
f
To Alnath
TO LOCATERefer to
Star ChartsA,D
& R
M2
NGC Summary by J.L.E. Dreyer, circa 1888NGC Number: 7089Mag: 6.5 Size: 12.9'NGC Description: Very remarkable!! Globular cluster of stars, bright, verylarge, gradually becomes pretty muchbrighter in the middle, well resolved,contains extremely faint stars.
Location Constellation: Aquarius (Aqr)
Year 2000 CoordinatesRA: 21h 33.5mDec: – 0° 49'
Observation PeriodsEvenings 8 p.m. : August to DecemberMornings 4 a.m. : April to August
M2 � Globular Cluster Description of M2 using a 4-inch refractor at 48xOverall, pretty bright and large. Very noticeable. Similar to M15. Bright centerthat fades outward. In an area sparsewith stars.
Locating Index: Fairly easy since it forms the right angle of a triangle with the two brightest stars in the handle of Aquarius, a and b Aquarii.Identifying/Observing Index: Easy sincethis jewel is bright and thus stands outwhen you come across it.
ARCSCALE
10'
20'
5'
15'
25'
1/2°
0'
N
1°
3/4°
M2 is a surprising joy in an area devoid of brighter stars.
Original Messier Descriptionfrom the 1784 edition of Connaissance des Temps
Observed 1760. Sept. 11
Nebula without stars in the head ofAquarius, its center is brilliant & the lightsurrounding it is circular. It resemblesthe beautiful nebula located between the head & bow of Sagittarius. You cansee it very well with a two-foot telescopeplaced on the parallel of the a of Aquar-ius. Mr. Messier reported this nebula onthe Chart of the track of the Comet ob-served in 1759. Mém. Acad. year 1760,page 464. Mr. Maraldi had seen this neb-ula in 1746, while observing the Cometwhich appeared that year.*
FactsName: No common nameType of Object: Globular clusterMagnitude: 62Distance: 40,000 lyPhysical Size: 151 ly in diameterArc Degree Size in Sky: 13' in diameterOther: The stars in this globular clusterare very tightly compacted and are rated II on a I to XII scale where I is the mostcompact. See Globular Cluster in theglossary for more information.
111For easy comparison, all photographs are shown at the same scale, measuring 2.3° x 1.3°.110
Author’s Note: Jean-Dominique Maraldi (1709–1788) was originallyfrom Italy, but later moved to Paris. He was related to Cassini. InParis, he worked on measuring longitude using Jupiter’s moons, observed comets and assisted in the publication of 25 annual issues of Connaissance des Temps.
*