The Local Group of Galaxies

The Local Group is our small cluster of galaxies; it was first recognized by Hubble, in the time of the first distance determinations and redshift measurements. A total of three or four large and over 30 small galaxies are members of this group.

Here we present information and - whereever available - images of the Local Group galaxies, candidates and some former candidates. Please send me images or info on images of those galaxies which don't already have one!

List of all images

Discovery of the Local Group Galaxies

Local Group Galaxies by Name

Local Group Member Galaxies

Galaxy             Con  RA      Dec        mag        dim

WLM                Cet  00:02.0 -15:28   10.9v     12 x 4
IC 10              Cas  00:20.4 +59:18   10.3v    7.3 x 6.4
Cet dw             Cet  00:26.1 -11:02   14.4     5.0 x 4.3
NGC 147            Cas  00:33.2 +48:31    9.5v   15.0 x 9.4
And III            And  00:35.4 +36:31   13.5p    4.5 x 3.0
NGC 185            Cas  00:39.0 +84:20    9.2v   14.5 x 12.5
M 110              And  00:41.3 +41:41    8.5v   19.5 x 12.5
And VIII           And  00:42.3 +40:37    9.1v   45   x 10
M 32               And  00:42.7 +40:52    8.1v   11.0 x 7.3
M 31               And  00:42.7 +41:16    3.4v  185.0 x 75.0
And I              And  00:45.7 +38:00   13.2     2.5 x 2.5
SMC                Tuc  00:51.7 -73:14    2.3v    280 x 160
And IX             And  00:52.9 +43:12   16.2         5
Scl dw             Scl  01:00.0 -33:42   10.5p   39.8 x 30.9
LGS 3 (Psc dw)     Psc  01:03.8 +21:53   15.4p        2
IC 1613            Cet  01:05.1 +02:08    9.2v   20.0 x 18.5
And X              And  01:06.6 +44:48   16.1         7
And V              And  01:10.3 +47:38   15.9     2.0 x 1.5
And II             And  01:16.4 +33:27   13.5     3.6 x 2.5
M 33               Tri  01:33.9 +30:39    5.7v   67.0 x 41.5
Phe dw             Phe  01:51.1 -44:27   13.1     4.9 x 4.1
For dw             For  02:39.9 -34:32    8.1v   12.0 x 10.2
UGCA 92            Cam  04:32.0 +63:36   13.8     2.0 x 1.0
LMC                Dor  05:19.7 -68:57    0.1v    650 x 550
Car dw             Car  06:14.6 -50:58   20.9v   23.5 x 15.5
CMa dw             CMa  07:15   -28               720
Leo A (Leo III)    Leo  09:59.4 +30:45   12.9     5.1 x 3.1
Sex B              Sex  10:00.0 +05:20   11.8     5.1 x 3.5
NGC 3109           Hya  10:03.1 -26:09   10.4    16.0 x 2.9
Ant dw             Ant  10:04.1 -27:20   14.8     2.0 x 1.5
Leo I              Leo  10:08.5 +12:18    9.8     9.8 x 7.4
Sex A              Sex  10:11.1 -04:43   11.9     5.9 x 4.9
Sex dw             Sex  10:13.2 -01:37   12.     30.0 x 12.0
Leo II (Leo B)     Leo  11:13.5 +22:10   12.6    12.0 x 11.0
GR  8              Vir  12:58.7 +14:13   14.5p    1.2 x 1.1
UMi dw             UMi  15:08.8 +67:12   10.9v   41.0 x 26.0
Dra dw             Dra  17:20.1 +57:55    9.9v   51.0 x 31.0
Milky Way    cent: Sgr  17:45.6 -28:56   
SagDEG (Sag dSph)  Sgr  18:55   -30:30    4.5   450.0 x 216.0
Sgr dw (SagDIG)    Sgr  19:30.1 -17:42   15.5     2.9 x 2.1
NGC 6822 (DDO 209) Sgr  19:44.9 -14:49    9.3    15.5 x 13.5
Aqr dw (AqrDIG)    Aqr  20:46.8 -12:51   13.9v    2.3 x 1.2
Tuc dw             Tuc  22:41.7 -64:25   15.7     2.9 x 1.2
UKS2323-326        Scl  23:26.5 -32:23   13.9     1.5 x 1.2
And VII (Cas dSph) Cas  23:27.8 +50:35   12.9     2.5 x 2.0
Peg dw             Peg  23:28.6 +14:45   13.2     5.0 x 2.7
And VI (Peg dSph)  Peg  23:51.7 +24:36   11.2     3.5 x 3.5

Possible Further Members

UGCA 86 Cam 03:59.9 +67:08 13.5 0.8 x 0.7 IC 5152 Ind 22:02.9 -51:17 10.6v 4.9 x 3.0

Willman 1 (UMa I) UMa 10:49.4 +51:03 15.3 1.75 UMa I UMa 10:34.9 +51:55 UMa II UMa 08:51.5 +63:08 14.3 Vir Stream Vir 12:24 -01.1 30 x 10 CVn I CVn 13:28.1 +33:33 13.9 8.4 x 5.0 Boo dw Boo 14:00.0 +14:30 13.6 13.0 x 8.7 Leo T Leo 09:34.9 +17:03 16.0 1.4 x 1.4 Com dw Com 12:27.0 +23:54 14.5 5.0 x 2.5 CVn II CVn 12:57.2 +34:19 15.1 3.0 x 2.1 Her dw Her 16:31.0 +12:48 14.7 8.0 x 6.0 Leo IV Leo 11:32.9 -00:32 15.9 3.3 x 2.5

And XI And 00:46.3 +33:48 0.5 And XII And 00:47.4 +34:22 0.55 And XIII And 00:51.8 +33:00 0.5 And XIV And 00:51.6 +29:41

And XV And 01:14:18.7 +38:07:03 And XVI And 00:59:29.8 +32:22:36 And XVII And 00:37:07.0 +44:19:20 And XVIII And 00:02:14.5 +45:05:20 And XIX And 00:19:32.10 +35:02:37.1 And XX And 00:07:30.70 +35:07:56.4 And XXI And 23:54:47.7 +42:28:15 And XXII And 01:27:40.0 +28:05:25 And XXIII And 01:29:21.8 +38:43:08 And XXIV And 01:18:30.0 +46:21:58 And XXV And 00:30:08.9 +46:51:07 And XXVI And 00:23:45.6 +47:54:58 And XXVII And 00:37:27.1 +45:23:13 And XXVIII And 22:32:41.20 +31:12:58.2 And XXIX And 23:58:55.6 +30:45:20

Nearby Non-Member (?) Galaxies

                
NGC 55             Scl  00:14.9 -39:11    8.8    32.4 x 5.6
NGC 404            And  01:09.4 +35:43   10.1v    4.4 x 4.1 
Cam A              Cam  04:25.3 +72:48   14.8     3.7 x 2.1
NGC 1569           Cam  04:30.8 +64:51   11.2v    2.9 x 1.5
NGC 1560           Cam  04:32.8 +71:53   11.5v    9.8 x 2.0
Argo dw (Car II)   Car  07:05.3 -58:31   14.2     3.5 x 1.7
UGC 9128 (DDO 187) Boo  14:15.9 +23:03   14.4     1.7 x 1.3

Key:

Galaxy: Identification of the galaxy
Con: Constellation
RA, Dec:: Right Ascension and Declination for epoch 2000.0
mag: Apparent magnitude (v: visual, p: photographic)
dim: Dimension in arc minutes

Astronomical data

Probable Local Group Members:

                
Galaxy     Other name Rm Type             RV    Dist  Diam  Mass
                                                      
WLM                   *  IB(s) IV-V       - 42  3400     8       ?
IC 10                    KBm?             - 83  4200:      
Cet dw                I  dE4                    2800
NGC 147    DDO 3         dE5 pec          + 89  2400 
And III                  dE2                    2900: 
NGC 185                  dE3 pec          + 39  2300 
M110       NGC 205       E5 pec           -  1  2900    17   10000
M32        NGC 221       E2 (cE2)         + 35  2900     8    3000
M31        NGC 224       SA(s)b I-II      - 59  2900   195  400000
And I                    dE3 pec ?              2900: 
SMC        NGC 292       SB(s)m pec       - 30   210    25    6000
And IX                   dSph
Scl dw     E351-G30      dE3 pec          +162   300: 
LGS 3      Psc dw     *  Irr                    3000: 
IC 1613    DDO 8         IAB(s)m V        -125  2900: 
And X                    dSph                   2900:
And V                    dSph                   2900:
And II                   dE0                    2900: 
M33        NGC 598       SA(s)cd II-III   +  3  3000    60   25000
Phe dw                I  Irr                    1600:      
For dw     E356-G04      dE2                     530:
UGCA 92    EGB0427+63 I  Irr ? S0 ?       + 66  4700       
LMC                      SB(s)m           + 13   179    30   20000
Car dw     E206-G220     dE3                     360  
CMa dw                   Irr                      25
Leo A      Leo III    ?  IBm V            - 26  2500  
Sex B      DDO 70     I  Ir+ IV-V               4700      
NGC 3109   DDO 236    I  Ir+ IV-V         +131  4500
Ant dw     PGC 29194  I  dE3                    4600     5 
Leo I      Regulus G.    dE3                     900  
Sex A      DDO 75        Ir+ V                  5200  
Sex dw                   dE3                     320  
Leo II     Leo B         dE0 pec                 750  
GR  8      DDO 155    ?  Im V             +165  7900:
UMi dw     DDO 199       dE4                     240  
Dra dw     DDO 208       dE0 pec           -31   280  
Milky Way                SAB(s)bc I-II ?     0    28   100  750000
SagDEG     Sgr I dw   *  dE7                      80       
Sgr dw     SagDIG     *  IB(s)m V               4200 
NGC 6822   Barnard's     IB(s)m IV-V      + 66  1800
Aqr dw     DDO 210    ?  Im V                   3400
Tuc dw                   dE5                    3200
UKS2323-326               Irr                   4700       
And VII    Cas dSph      dSph                   2600 
Peg dw     DDO 216       Im V                   3000:
And VI     Peg dSph      dSph                   2800

Possible Further Members:

UGCA 86               ?  Irr ? S0 ?       +262  6200      
IC 5152               ?  IAB(s)m IV       + 30  5800

Wilman 1                 dSph ? GC ?             147
UMa I                    dSph                    330
UMa II                   dSph                    815
Vir Stream               dSph                     30
CVn I                    dSph                    730
Boo dw                   dSph                    200
Leo T                    dSph                   1370
Com dw                   dSph                    143            
CVn II                   dSph                    490
Her                      dSph                    460
Leo IV                   dSph                    520

And XI                   dSph                   2900:
And XII                  dSph                   2900:
And XIII                 dSph                   2900:
And XIV                  dSph                   2900:

Probable Nearby Non-Members:

Galaxy    Other name  Rm   Type           RV    Dist   Diam  Mass  
                        
NGC 55                    Sc              +129  7000::
NGC 404                   E0 or SA(s)0-   +178  8000::             
NGC 1569                  Irp+ III-IV:    + 87  7500::
NGC 1560  IC 2062         Sd              +151  7500::
Cam A                     Irr                   6500::
Argo dw   AM 0704-582     Irr                  12000::       
UGC 9128  DDO 187         Irp+            +154

Key:

Rm:: Remarks: *, ? and I; see below
Type:: Classification type from Tom Polakis' article
RV:: Radial velocity wrt galactic center in km/sec
Dist:: Distance in 1000 light years
Diam:: Diameter in 1000 light years
Mass:: Mass in million solar masses

Remarks "*":

"WLM" is "Wolf-Lundmark-Melotte"
And IV is probably either a large open cluster or star cloud in M31 and not an independent galaxy, or a remote background galaxy
"LGS" stands for "Local Group (suspected)" (LGS 3)
"SagDEG" is the "Sagittarius Dwarf Elliptical Galaxy" (discovered 1994, containing M54)
"SagDIG" is the "Sagittarius Dwarf Irregular Galaxy"

Galaxies marked with "?" may be non-members as they are not in the list of Irwin et.al. 1997 (this list has 35 Local Group members), in particular:

UGCA 86 may be a member of the Maffei 1 group
Leo A, GR8, the Aquarius Dwarf and IC 5152 are listed as nearby non-member galaxies in Mike Irwin's list. Leo A and Aquarius Dwarf have since been confirmed by new data.

Galaxies marked with "I" are newly taken into the list from Irwin's list (besides the newly discovered Antlia dwarf, these are the Phoenix dwarf, UGCA 92, Sextans B, and NGC 3109.

Doubty or unconfirmed candidates listed in some sources:

Galaxy             listed     Remarks

1010-27            McGraw     (= Ant dw ?)
Snickers

Former Candidates

Object             Listed     Remarks

LGS 2              I          Reflection nebulosity (or remote dwarf galaxy)
Sex C (A 1003)     dV, LGAA   Palomar 3, a remote Milky Way globular cluster
UMa dw (A 1127)    dV, LGAA   Palomar 4, a remote Milky Way globular cluster 
Ser dw (A 1513)    dV         Palomar 5, a remote Milky Way globular cluster
Cap dw (A 2144)    dV,McGraw  Now identified as globular cluster Palomar 12
And IV             vdB        Background galaxy, or star cluster in M31
SDIG               KKT        Member of the Sculptor Group of Galaxies
IC 342             Hubble     Member of the Maffei 1 or IC 342 Group of Galaxies
Maffei 1           Maffei     Member of the Maffei 1 or IC 342 Group of Galaxies
Maffei 2           Maffei     Member of the Maffei 1 or IC 342 Group of Galaxies
NGC 6946           Hubble     Nearby non-member
2318-42            I          A candidate before its redshift was measured

Sources:

McGraw: McGraw-Hill Dictionary of Astronomy, by Sybil P. Parker (ed), p. 242
LGAA: Le Grand Atlas de L'Astronomie, Encyclopedia Universalis, 1986. German edition: "Der große JRO Atlas der Astronomie"
KKT: Kraan-Korteweg & Tammann, 1979. Astronomische Nachrichten 300, p. 181
Maffei: P. Maffei 1968, PASP 80, p. 618
vdB: S. van den Bergh 1972, Search for Faint Companions to M31. ApJl 171, p. L31-L33
dV: G. De Vaucouleurs 1975, Nearby Groups of Galaxies, ch. 4, The Local Group. Published in "Galaxies and the Universe," ed. by A. Sandage, M. Sandage and J. Kristian.

"Galaxy"           Con  RA      Dec       mag        dim

SDIG               Scl  00:08.2 -34:35   15.5     1.1 x 0.9
LGS 2              And  00:29.3 +33:21   19         3 x 2
And IV             And  00:42.5 +40:34  
Maffei 1           Cas  02:36.3 +59:39   11.4     3.4 x 1.7
Maffei 2           Cas  02:41.9 +59:36   16.0     5.8 x 1.6
IC 342             Cam  03:46.8 +68:06    9.1    21.4 x 20.9
Snickers           Aur  06:28   +15
Sex C              Sex  10:05.5 +00:04   14.3        2.8
UMa dw             UMa  11:29.3 +28:58   14.2        2.1
Ser dw             Ser  15:16.1 -00:07   11.8        6.9
NGC 6946           Cep  20:34.8 +60:09    8.9    11.0 x 10.0
Cap dw             Cap  21:46.6 +21:15   12.0       17.4
2318-42            Gru  23:20.8 -41:44   14.6     1.7 x 1.4

Galaxy    Other name  Rm   Type           RV     Dist   Diam  Mass  

SDIG      PGC 621          IBm            +207  10000
LGS 2     PGC 1792    DN?  dwarf G or Nb
And IV    PGC 2544    OC?  Irr G or OC           2900?  
Maffei 1  UGCA 34          E/S0- pec:     + 13  10000
Maffei 2  UGCA 39          SBb            - 17  10000
IC 342    UGC 2847         Sc             + 31  10000
Snickers
Sex C     Palomar 3   GC                          302
UMa dw    Palomar 4   GC                          356
Ser dw    Palomar 5   GC                           76
NGC 6946  H IV.76          Sc             +338  10000
Cap dw    Palomar 12  GC                  + 28     62   .017
2318-42   E347-G008        Irr           +1640  70000:

As our Milky Way obscures parts of the sky, there is still a steady flow of new discoveries of galaxies, in low galactic latitudes (i.e., near the equatorial plane of our galaxy, where the obscuring dust is most dense). Also, some of the galaxies are of extreme low surface brightness, and it was only recently possible to detect them. Therefore, it must be expected that more Local Group members exist, obscurred by dust, or extremely faint, and are still waiting for their detection somewhen in the future.

References

Tom Polakis has published an interesting article for observers of local group galaxies, Observing the Local Group, in the Deep Sky magazine (#36), which was reprinted in David Eicher's book Galaxies and the Universe

Note: The images displayed in these pages were generously contributed by their various authors. Some of the images shown in the pages linked here are subject to third-party rights which we would like to be respectfully observed.

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Hartmut Frommert
Christine Kronberg
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