The Local Group

The Local Group of Galaxies (LG) is a small but diverse collection of different types of galaxies: First the three big spirals (S) - our Milky Way (MW), the Andromeda Galaxy M31, and the Triangulum Galaxy M33, itself maybe a satellite of M31. Then there are some elliptical (E) and irregular (I or S[B]m) galaxies, as satellites of the big ones or field members of the Local Group. Furthermore there is the small formation of dwarf galaxies around NGC 3109, which may or may not be members of the LG.

And then there are the little ones: plenty of dwarf spheroidal (dSph) and only recently discovered ultra faint dwarf (UFD) galaxies at the lower size limit toward globular clusters. Not to forget the many less observable features as gaseous and dark matter halos and stellar tidal streams.

With this chart here I tried to show all the discovered galactic members of the Local Group as seen from Earth, with known (or at least suspected) subgroups color-coded (see below). Because of the concentration of satellites around M31 the complete galaxy names are only visible at higher zoom level. Rotate the view with mouse- or fingertip-dragging, zoom with mouse wheel or pinch, depending on what kind of interface you are using. The source for the underlying map can be found at my Github repository.

The equatorial yellow line is the galactic plane and the pink line is the supergalactic plane.

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Subgroups:
Milky Way
M31(Andromeda)
NGC 3109
Galaxy Types:
Spiral
Elliptical
Irregular

Dwarf Spheroidal (dSph)
Ultra Faint Dwarf (UFD)

In the last decades many discoveries have improved our picture of the Local Group. In particular the Sloan Digital Sky survey (SDSS), the PAndAS survey (Pan-Andromeda Archaeological Survey) and Gaia have enabled many discoveries of very faint objects, while infrared surveys continue to search through the galactic plane to find objects so far hidden behind it. The SDSS has for the most part only probed the northern hemisphere, so there may also lurk many undiscovered dSphs and UFDs in the southern hemisphere.

As the count stands so far, there are 122 members of the Local Group so far and 5 probables. 65 are satellites of the Milky Way, 42 of M31. The census by morphological type: 8 (dwarf)spirals, 5 ellipticals, 18 irregulars, 43 dwarf spheroidals and 53 UFDs. Below is a list with data of all members and candidates:

Name         Alt. Name  l      b      M      Rh     Dh      Dnear   Metal.  Type      Subgroup
                        °      °      mag    pc     kpc     kpc     [Fe/H]                    
Milky Way        Gal.Cntr.         0      0    -20.9            8.5   460             SABbc I-II   MW  
Sagittarius I    SagDEG            5.57 -14.16 -13.5  1550     26      16.0   -0.5    dSph(t)      MW  
UKS 2323-326     UGCA 438         11.87 -70.86 -13.1          770    1350             IBm V-VI pec LG??
Sagittarius II   Laevens 5        18.9  -22.9   -5.2    32     67      60     -2.28   UFD          MW  
SagDIG           Sagittarius dIrr 21.06 -16.28 -11.5          930    1180     -2.1    IBm V-VI:    LG  
NGC 6822         DDO 209          25.35 -18.38 -16.0          490     670     -1.2    IBm V-VI     LG  
Boötes III       Boö III          27.39  55.43  -5.8   170     46      44.0   -2.1    UFD          MW  
Hercules I       Her I            28.73  36.87  -6.6   330    132     134.2   -2.41   UFD          MW  
Aquarius I       DDO 210          34.05 -31.34 -10.6   216    565     960     -1.3    IBm V-VI     LG  
Aquarius II                       55.11 -53.01  -4.36  159    108             -2.3    UFD          MW  
Pegasus III                       69.85 -41.81  -3.4    78    215             -2.1    UFD          MW  
Boötes IV        Boö IV           70.682 53.305 -4.53  462    209             -2.2    UFD          MW  
Canes Venatici  ICVn I            74.31  79.82  -8.6   564    218     219.8   -1.98   dSph         MW  
WLM              DDO 221          75.86 -73.62 -14.2   917   1122     810     -1.27   IBm V-VI     LG  
Pisces II                         79.21 -47.11  -5.0    60    182     180     -2.45   UFD          MW  
Draco I          DDO 208          86.37  34.72  -8.8   196     76      82     -1.93   dSph pec     MW  
Andromeda XXVIII                  91.03 -22.93  -8.5   210    650     365     -2.0    dSph         M31 
PegDIG           DDO 216          94.78 -43.55 -12.2          783     410     -1.4    Im V-VI      M31?
Draco II         Laevens 4        98.3   42.9   -2.9    19     21.5    22     -2.7    UFD          MW  
Lacerta I        Andromeda XXXI  101.1  -16.7  -11.7   912    756     275             dSph         M31 
Cetus I          KKS 1           101.46 -72.85 -11.2   590    755     620     -1.9    dSph         LG  
Ursa Minor I     DDO 199         104.97  44.80  -8.8   280     76.0    68.0   -2.13   dSph         MW  
Pegasus I        Andromeda VI    106.04 -36.32 -11.3   424    919     265     -1.3    dSph         M31 
Cassiopeia I     Andromeda VII   109.46  -9.95 -12.6   740    763     215     -1.4    dSph         M31 
Andromeda XXIX                   109.80 -30.77  -8.3   360    730     207     -1.8    dSph         M31 
Andromeda XXI                    111.9  -19.2   -9.9   842    827     135     -1.8    dSph         M31 
Andromeda XX                     112.9  -26.9   -6.3   114    741     128     -1.5    UFD          M31 
Canes Venatici IICVn II          113.58  82.70  -4.9    74    160     150.7   -2.21   UFD          MW  
Andromeda XVIII                  113.9  -16.9   -9.7   325   1214     357     -1.8    dSph         M31?
Andromeda XIX                    115.6  -27.4   -9.2  1481    821     115     -1.9    dSph         M31 
Andromeda XXVI                   118.1  -14.7   -7.1   219    754     103     -1.9    dSph         M31 
IC 10                            118.96  -3.33 -15.0   500    660     255     -1.28   IBm V-VI     M31?
Andromeda XXV                    119.2  -15.9   -9.7   642    736      90     -1.8    dSph         M31 
Andromeda III    KK 5            119.37 -26.26 -10.2   360    723      86     -1.78   dSph         M31 
NGC 147          DDO 3           119.82 -14.25 -15.1   503    712     118     -1.1    dE5          M31 
Andromeda XVII                   120.23 -18.47  -8.7   262    727      67     -1.9    dSph         M31 
Andromeda XXVII                  120.4  -17.4   -7.9   657   1255     482     -1.7    dSph         M31 
Cassiopeia II    Andromeda XXX   120.46 -13.15  -8.0   267    681     145     -1.7    dSph         M31 
Cassiopeia III   Andromeda XXXII 120.5  -11.2  -12.3  1456    772     144             dSph         M31 
M110             NGC 205         120.72 -21.14 -16.5   673    824      60     -0.8    dE5/p        M31 
NGC 185                          120.79 -14.48 -15.2   266    620     181     -0.8    dE3          M31 
Andromeda VIII   M31 part        121.02 -22.22                830       -             dSph pec:    M31 
Andromeda IV                     121.11 -22.27 -12.6         6300       -             dIrr:        ??  
M32              NGC 221         121.15 -21.98 -16.4   220    770       6     -1.1    cE2          M31 
M31              NGC 224         121.17 -21.57 -21.2  4760    785     300      0.42   SAb II       M31 
Andromeda I      KK 8            121.68 -24.82 -11.8   600    727      68     -1.45   dSph/dE3     M31 
Andromeda XI                     121.72 -29.06  -6.9   158    763     102     -2.0    UFD          M31 
Andromeda XII                    122.00 -28.49  -6.4   324    928     181     -2.1    UFD          M31 
Andromeda XIV                    122.97 -33.17  -8.4   413    793     161     -2.26   dSph         M31 
Andromeda XIII                   123.03 -29.87  -6.7   172    760     115     -1.9    UFD          M31 
Andromeda IX                     123.21 -19.68  -8.1   530    600     182     -2.2    dSph         M31 
Andromeda XVI                    124.91 -30.46  -9.2   170    476     319     -2.1    dSph         M31 
Andromeda X                      125.75 -17.98  -7.6   340    670     130     -1.93   dSph         M31 
Andromeda V                      126.22 -15.12  -9.1   302    742     113     -1.9    dSph         M31 
LGS 3            Pisces I        126.76 -40.89 -10.1          769     285     -2.1    dIrr/dSph    M31?
Andromeda XXIV                   127.8  -16.3   -7.6   548    898     169     -1.8    dSph         M31 
Andromeda XV                     127.88 -24.53  -9.4   270    626     174     -1.8    dSph         M31 
Andromeda II     KK 12           128.92 -29.16 -12.4  1230    630     195     -1.64   dSph         M31 
IC 1613          DDO 8           129.74 -60.58 -15.3  1440    715     505     -1.3    IBm V-VI     M31?
Andromeda XXIII                  131.0  -23.6  -10.2  1001    748     127     -1.8    dSph         M31 
Andromeda XXII   (Tri I)         132.6  -34.1   -6.5   252    920     275     -1.8    UFD          M31 
M33              NGC 598         133.61 -31.33 -18.9  3320    820     210     -0.3    SAcd III-IV  M31?
UGCA 86                          139.76  10.65 -17.7          525    3770             Im V-VI:     LG??
Triangulum II    Laevens 2       141.4  -23.4   -1.8    16     28.4    36     -2.24   UFD          MW  
UGCA 92                          144.71  10.52 -14.5          640                     Im V-VI:     LG??
Andromeda XXXIII Perseus I       147.8  -15.5  0,3     400    785     374             dSph         M31 
Segue II                         149.4  -38.1   -2.5    40     37      38.0   -2.22   UFD          MW  
Ursa Major II    UMa II          152.46  37.44  -4.2   140     32      36.5   -2.47   UFD          MW  
Cetus II                         156.48 -78.53   0.0    17     30             -1.28   UFD          MW  
Willman 1                        158.58  56.78  -2.7    25     38      43     -2.1    UFD          MW  
Ursa Major I     UMa I           159.43  54.41  -5.5   318     97     104.9   -2.18   UFD          MW  
Cetus III                        163.81 -61.13  -2.5    90    251             -2.2    UFD          MW  
UGC 4879         VV 124          164.67  42.88 -12.5         1100    1000     -1.5    IAm          LG??
Leo A            DDO 69          196.90  52.42 -12.1   475    950     980     -1.4    IBm V-VI     LG  
Leo T                            214.85  43.66  -8.0   178    417     425     -2.02   UFD          MW? 
Leo P                            219.65  54.43  -9.41  290   1750             -1.8    dSph         LG? 
Leo II           DDO 93          220.17  67.23  -9.8   151    233     208     -1.62   dSph pec     MW  
Segue I                          220.5   50.4   -1.5    29     23      25     -2.72   UFD          MW  
Hydra I          Hya I           224.7   29.1   -2.5           12.7           -0.91   UFD          MW  
Leo I            DDO 74          225.99  49.11 -12.0   246    254     254     -1.43   dSph         MW  
Columba I        Col 1           231.62 -28.88  -4.5   103    182                     UFD          MW  
Sextans B        DDO 70          233.20  43.78 -14.5   715   1630     730     -1.6    IBm V-VI     N310
Fornax I         ESO 356-4       237.10 -65.65 -13.4   668    147     140     -0.99   dSph         MW  
Canis Major I    CMa I           239.99  -8.00  -8.3           13.0     8.0           dIrr         MW  
Coma Berenices I Com I           241.9   83.6   -4.1    77     44      45.2   -2.6    UFD          MW  
Sextans I                        243.50  42.27  -9.27  682     86      89     -1.93   dSph         MW  
Sextans A        DDO 75          246.15  39.88 -14.3   300   1380     530     -1.85   IBm V-VI     N310
Eridanus II                      249.78 -51.65  -6.6   172    380             -2.38   UFD          MW  
Pictor I                         257.30 -40.65  -3.7    31    126             -1.7    UFD          MW  
Antlia B         Ant B           259.41  21.08  -9.7   273   1290      70     -0.5    dSph         N310
Carina I         Car 1           260.11 -22.22  -9.1   241    105     103     -1.72   dSph         MW  
Leo V                            261.86  58.54  -5.2    42    178     180.8   -2.0    UFD          MW  
NGC 3109         DDO 236         262.10  23.07 -15.8         1285    1720     -1.7    SBm V        N310
Horologium II                    262.47 -54.14  -2.6    47     78             -2.1    UFD          MW  
Antlia A         Ant A           263.10  22.31 -10.7         1320      40     -1.9    IABm V-VI    N310
Antlia II        Ant II          264.90  11.25  -8.5  2867    129.4           -1.36   dSph         MW  
Leo IV                           265.44  56.51  -5.8   116    154     160.6   -2.54   UFD          MW  
Reticulum II                     266.30 -49.74  -2.7    32     32             -2.46   UFD          MW  
Pictor II        Pic II          269.63 -24.05  -3.2    46     45             -1.8    UFD          MW  
Carina II        Car II          269.98 -17.14  -4.5    91     36.2           -2.44   UFD          MW  
Carina III       Car III         270.01 -16.85  -2.4    30     27.8           -1.80   UFD          MW  
Horologium I                     271.39 -54.73  -3.4    30     79             -2.76   UFD          MW  
Phenix I         ESO 245-7       272.16 -68.95  -9.8          445     445     -1.49   IAm V-VI     MW? 
Reticulum III                    273.88 -45.65  -3.3    64     92                     UFD          MW  
Eridanus III                     274.3  -59.60  -2.0    18     87                     UFD          MW  
Virgo I          Vir I           276.94  59.58  -0.3    47     91             -2.2    UFD          MW  
LMC                              280.47 -32.89 -18.5  3000     51      50     -0.6    SBm V        MW  
Crater II        Crt II          282.91  42.03  -8.2  1066    118             -1.98   dSph         MW  
Sculptor I                       287.54 -83.16 -10.8   279     86      79     -1.68   dSph         MW  
Hydra II         Hya II          295.61  30.46  -4.8    68    134     128     -2.02   UFD          MW  
Hydrus I                         297.41 -36.74  -4.7    53.3   27.6           -2.52   UFD          MW  
Centaurus I      Cen I           300.26  21.90  -5.6    79    116.3   112.7   -1.8    UFD          MW  
SMC              NGC 292         302.80 -44.30 -16.8  1000     64      57     -1.2    SBm V pec    MW  
GR 8             DDO 155         310.74  76.98 -12.5   108    940    2500     -2.0    Im V-VI      LG??
Tucana IV                        313.29 -55.29  -3.5   127     48             -2.49   UFD          MW  
Tucana III                       315.15 -56.19  -2.4    44     25             -2.42   UFD          MW  
Tucana V                         316.31 -51.89  -1.6    17     55             -2.17   UFD          MW  
Tucana I                         322.91 -47.37  -9.6   207    875    1110     -1.58   dE4          LG  
Phenix II                        323.69 -59.75  -3.7    27     95                     UFD          MW  
Tucana II                        328.08 -52.33  -3.8   199     57             -2.23   UFD          MW  
Grus I                           338.68 -58.24  -3.4    70    120             -0.42   UFD          MW  
IC 5152          ESO 237-27      343.92 -50.19 -15.7          590    1830     -1.4    IAm V-VI     LG??
Indus I                          347.3  -42.6   -3.5    12    100.0                   UFD          MW  
Grus II                          351.15 -51.94  -3.9    93     53             -2.51   UFD          MW  
Boötes II        Boö II          353.7   68.9   -2.7    51     52      47.6   -1.79   UFD          MW  
Indus II                         353.99 -37.40  -4.3   181    214             -2.0    UFD          MW  
Boötes I         Boötes I        358.08  69.62  -6.3   242     66      57.6   -2.55   UFD          MW  

M:  Absolute visual Magnitude, Rh: Half light radius in pc.
Dh: Heliocentric distance in kpc.
Dnear: Distance to the nearest Subgroup center (MW, M31, NGC 3109) in kpc, for those and LG field galaxies 
    distance to the Local Group barycenter in kpc.

Metal. [Fe/H]: Metallicity = log(NFe/NH)star - log(NFe/NH)sun
    Logarithm of the average abundance of elements heavier than helium and hydrogen (= metals), measured as 
    the spectral ratio of iron to hydrogen relative to the solar ratio.
 
Subgroup: 
    There are three such groups currently recognized in the Local Group:
    MW: The Milky Way and it's satellite galacies 
    M31: Andromeda (including M33) and satellites  
    N3109: The small NGC 3109 group, possible Local Group member
    LG are Local Group galaxies not belonging to any subgroup
    ? means probable, ?? unlikely membership.

Links & References
Old versions of the chart
Milky Way Satellites & The Local Group (SEDS)
Mike Irwin List of Local Group members
PAndAS (The Pan-Andromeda Archaeological Survey)

Metz et al. (2006) The spatial distribution of the Milky Way and Andromeda satellite galaxies arXiv:astro-ph/0610.933v1
Metz et al. (2009) Discs of Satellites: the new dwarf spheroidals arXiv:astro-ph/0901.1658v1

Discovery papers
Milky Way:
Martin et al. (2003) A dwarf galaxy remnant in Canis Major: The fossil of an in-plane accretion onto the Milky Way arXiv:astro-ph/0311.010v1 (CMa dwarf)
Willmann et al. (2005) A New Milky Way Dwarf Galaxy in Ursa Major arXiv:astro-ph/0503.552v2 (UMa I)
Zucker et al. (2006) A New Milky Way Dwarf Satellite in Canes Venatici arXiv:astro-ph/0604.354v1 (CVn I)
Belokurov et al. (2006) Cats and Dogs, Hair and a Hero: A Quintet of New Milky Way Companions arXiv:astro-ph/0608.448v1 (Leo IV, CVn II, Com, Her dSphs & Segue 1)
Zucker et al. (2006) A Curious New Milky Way Satellite in Ursa Major arXiv:astro-ph/0606.633 (UMa II)
Irwin et al. (2007) Discovery of an Unusual Dwarf Galaxy in the Outskirts of the Milky Way arXiv:astro-ph/0701.154v1 (Leo T)
Walsh et al. (2007) A Pair of Boötes - A New Milky Way Satellite arXiv:astro-ph/0705.1378 (Boötes I & II)
Belokurov et al. (2008) Leo V - A Companion of a Companion of the Milky Way Galaxy? arXiv:astro-ph/0807.2831v2 (Leo V)
Belokurov et al. (2010) Big Fish, Small Fish: Two New Ultra-Faint Satellites of the Milky Way. arXiv:astro-ph/1002.0504v1 (Pisces II, Segue 3)
Grillmair, C.J. (2011) Another Look at the EBS: A Stellar Debris Stream and a Possible Progenitor. arXiv:astro-ph/1107.5044v1
Giovanelli et al. (2013) Alfalfa Discovery of the Nearby Gas-Rich Dwarf Galaxy Leo P. arXiv:astro-ph/1305.0272
Sand et al. (2015) Antlia B: A Faint Dwarf Galaxy Member of the NGC 3109 Association. arXiv:astro-ph/1508.01800

Andromeda:
Zucker et al. (2006) Andromeda X, A New Dwarf Spheroidal Satellite of M31: Photometry arXiv:astro-ph/0601.599 (And X)
Martin et al. (2006) Discovery and analysis of three faint dwarf galaxies and a globular cluster in the outer halo of the Andromeda galaxy. arXiv:astro-ph/0607.472v1 (And XI-XIII)
Majewski et al. (2007) Discovery of Andromeda XIV: A Dwarf Spheroidal Dynamical Rogue in the Local Group? arXiv:astro-ph/0702.635v2 (And XIV)
Ibata et al. (2007) The Haunted Halos of Andromeda and Triangulum: A Panorama of Galaxy Formation in Action. (And XV & XVI)
Irwin et al. (2008) Andromeda XVII: A New Low Lumiosity Satellite of M31. arXiv:astro-ph/0802.0698v1 (And XVII)
McConnachie et al. (2008) A trio of new Local Group galaxies with extreme properties. arXiv:astro-ph/0806.3988v1 (And XVIII-XX)
Collins et al. (2009) A Keck/DEIMOS spectroscopic survey of the faint M31 satellites And IX, AndXI, AndXII and AndXIII. arXiv:astro-ph/0911.1365v1
Martin et al. (2009) PAndAs' Cubs: discovery of two new dwarf galaxies in the surroundings of the Andromeda and Triangulum galaxies. arXiv:astro-ph/0909.0399v3 (And XXI+XXII)
Richardson et al. (2010) PAndAs' Progeny: Extending the M31 Dwarf Galaxy Cabal. arXiv:astro-ph/1102.2902v1 (And XXIII-XXVII)
Conn et al. (2012) A Bayesian Approach to Locating the Red Giant Branch Tip Magnitude (Part Ii): Distances to the Satellites of M31. arXiv:astro-ph/1209.4952
Slater et al. (2011) Andromeda XXVIII: A Dwarf Galaxy More Than 350 kpc from Andromeda arXiv:astro-ph/1110.5903
Bell et al. (2011) Andromeda XXIX: A New Dwarf Spheroidal Galaxy 200 kpc from Andromeda arXiv:astro-ph/1110.5906
Conn et al. (2013) The Three-Dimensional Structure of the M31 Satellite System: Strong Evidence for an Inhomogeneous Distribution of Satellites. arXiv:astro-ph/1301.7131
Martin et al. (2013) Lacerta I and Cassiopeia III: Two Luminous and Distant Andromeda Satellite Dwarf Galaxies Found in the 3? Pan-Starrs1 Survey (And XXXI/XXXII) arXiv:astro-ph/1305.5301