The local group is probably a typical group of galaxies. It consists of three large spiral galaxies surrounded by numerous dwarf galaxies. Very few of the smallest type of dwarf galaxies have ever been seen in any of the neighbouring galaxy groups, they are just too dim to be seen easily. Below are all the local group galaxies known at the beginning of 2007.
1 2 3 4 5 6 7 8
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Name of Galaxy | Galactic coords|Distance |Diameter| Galaxy | Other | Year of
| l° b° | (kly) | (kly) | Type | Name |Discovery
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Milky Way 0 0 0 90 SBbc prehist.
Sagittarius Dwarf 5.6 -14.1 78±7 20 dSph 1994
Ursa Major II 152.5 +37.4 100±15 1 dSph 2006
Coma Berenices Dwarf 241.9 +83.6 144±13 1 dSph 2006
Large Magellanic Cloud 280.5 -32.9 165±5 25 SBm ESO 56-115 prehist.
Small Magellanic Cloud 302.8 -44.3 195±15 15 SBm NGC 292 prehist.
Boötes Dwarf 358.0 +69.6 197±9 2 dSph 2006
Ursa Minor Dwarf 105.0 +44.8 215±10 2 dSph DDO 199 1954
Sculptor Dwarf 287.5 -83.2 258±13 3 dSph ESO 351-30 1937
Draco Dwarf 86.4 +34.7 267±20 2 dSph DDO 208 1954
Sextans Dwarf 243.4 +42.2 280±13 3 dSph PGC 88608 1990
Ursa Major I 159.4 +54.4 325? 3? dSph 2005
Carina Dwarf 260.1 -22.2 329±16 2 dSph PGC 19441 1977
Fornax Dwarf 237.1 -65.7 450±26 5 dSph ESO 356-04 1938
Hercules Dwarf 28.7 +36.9 457±41 4 dSph 2006
Canes Venatici II 113.6 +82.7 489±46 2 dSph 2006
Leo IV 265.4 +56.5 522±47 2 dSph 2006
Leo II 220.2 +67.2 669±39 3 dSph DDO 93 1950
Canes Venatici I 74.3 +79.8 718±82 6 dSph 2006
Leo I 226.0 +49.1 815±100 3 dSph DDO 74 1950
Leo T 214.9 +43.7 1360±65 2 dIrr/dSph 2007
Phoenix Dwarf 272.2 -68.9 1450±100 2 dIrr/dSph ESO 245-7 1976
NGC 6822 25.3 -18.4 1520±85 8 Irr DDO 209 1884
NGC 185 120.8 -14.5 2010±60 8 dSph/dE3p UGC 396 1787
Andromeda II 128.9 -29.2 2165±40 3 dSph PGC 4601 1970
Leo A 196.9 +52.4 2250±325 4 dIrr DDO 69 c1940
IC 1613 129.8 -60.6 2365±50 10 Irr DDO 8 c1890
Andromeda X 125.8 -18.0 2290±120 5 dSph 2006
NGC 147 119.8 -14.3 2370±50 10 dSph/dE5 DDO 3 c1830
Andromeda III 119.3 -26.2 2450±50 3 dSph PGC 2121 1970
Andromeda VII 109.5 -10.0 2465±95 2 dSph PGC 2807155 1999
Cetus Dwarf 101.4 -72.8 2485±65 3 dSph PGC 3097691 1999
Andromeda IX 123.2 -19.7 2505±75 4 dSph 2004
Andromeda I 121.7 -24.9 2520±60 2 dSph PGC 2666 1970
LGS 3 126.8 -40.9 2520±70 2 dIrr/dSph Pisces Dwarf 1978
Andromeda V 126.2 -15.1 2560±80 2 dSph PGC 3097824 1998
Andromeda Galaxy, M31 121.2 -21.6 2560±50 140 Sb NGC 224 c964
Andromeda XI 121.7 -29.1 2560±325 2 dSph 2006
Andromeda XII 122.0 -28.5 2560±325 2 dSph 2006
Andromeda XIII 123.0 -29.9 2560±325 2 dSph 2006
Andromeda VI 106.1 -36.3 2595±50 3 dSph PGC 2807158 1998
M32 121.2 -22.0 2625±115 8 dE2 NGC 221 1749
M110 120.7 -21.7 2690±80 15 dSph/dE5 NGC 205 1773
IC 10 119.0 -3.3 2690±165 8 dIrr UGC 192 c1890
Triangulum Galaxy, M33 133.6 -31.3 2735±55 55 Sc NGC 598 1654
Tucana Dwarf 322.9 -47.4 2870±130 2 dSph PGC 69519 1990
Pegasus Dwarf 94.8 -43.5 3000±80 6 dIrr/dSph DDO 216 ?
WLM 75.9 -73.6 3020±80 10 Irr DDO 221 1909
Aquarius Dwarf 34.0 -31.3 3345±100 3 dIrr/dSph DDO 210 1959
SagDIG 21.1 -16.3 3460±520 3 dIrr ESO 594-4 1977
Antlia Dwarf 263.1 +22.3 4030±210 3 dIrr/dSph PGC 29194 1997
NGC 3109 262.1 +23.1 4075±540 25 Irr DDO 236 c1836
Sextans A 246.2 +39.9 4350±120 10 dIrr DDO 75 ?
Sextans B 233.2 +43.8 4385±325 8 dIrr DDO 70 ?
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Column 1: The most common name of the galaxy.
Column 2: The galactic longitude of the galaxy.
Column 3: The galactic latitude of the galaxy.
Column 4: The distance to the galaxy in thousands of light years together with
the approximate error in the distance.
Column 5: The diameter of the galaxy in thousands of light years. For dwarf
galaxies this is only very approximate.
Column 6: The standard classification of the galaxy.
Column 7: Alternative catalogue name for the galaxy.
Column 8: Year the galaxy was discovered.
References:
Mateo M, (1998), Dwarf Galaxies of the Local Group. Annu Rev Astron Astrophys 36, 435.
van den Bergh S, (2000), Updated Information on the Local Group. Publications of the Astron
Soc of the Pacific, 112, 529.
McConnachie A, Irwin M, Ferguson A, Ibata R, Lewis G, Tanvir N, (2005), Distances and
Metallicities for 17 Local Group Galaxies. Monthly Notices of the Royal Astron Soc, 356, 979.
Zucker, Kniazev, Bell, Martínez-Delgado, Grebel, Rix, Rockosi, Holtzman, Walterbos, Annis, York,
Ivezić, Brinkmann, Brewington, Harvanek, Hennessy, Kleinman, Krzesinski, Long, Newman, Nitta,
Snedden, (2004), Andromeda IX: A New Dwarf Spheroidal Satellite of M31. Astrophys J, 612, L121
Willman, Dalcanton, Martinez-Delgado, West, Blanton, Hogg, Barentine, Brewington, Harvanek,
Kleinman, Krzesinski, Long, Neilsen, Nitta, Snedden, (2005), A New Milky Way Dwarf Galaxy
in Ursa Major. Astrophys J, 626, L85.
Zucker, Kniazev, Martínez-Delgado, Bell, Rix, Grebel, Holtzman, Walterbos, Rockosi, York,
Barentine, Brewington, Brinkmann, Harvanek, Kleinman, Krzesinski, Long, Neilsen, Nitta,
Snedden, (2007), Andromeda X, A New Dwarf Spheroidal Satellite of M31. Astrophys J, 659, L21.
Zucker, Belokurov, Evans, Wilkinson, Irwin, Sivarani, Hodgkin, Bramich, Irwin, Gilmore, Willman,
Vidrih, Fellhauer, Hewett, Beers, Bell, Grebel, Schneider, Newberg, Wyse, Rockosi, Yanny,
Lupton, Smith, Barentine, Brewington, Brinkmann, Harvanek, Kleinman, Krzesinski, Long, Nitta,
Snedden, (2006), A New Milky Way Dwarf Satellite in Canes Venatici. Astrophys J, 643, L103.
Belokurov, Zucker, Evans, Wilkinson, Irwin, Hodgkin, Bramich, Irwin, Gilmore, Willman, Vidrih,
Newberg, Wyse, Fellhauer, Hewett, Cole, Bell, Beers, Rockosi, Yanny, Grebel, Schneider,
Lupton, Barentine, Brewington, Brinkmann, Harvanek, Kleinman, Krzesinski, Long, Nitta, Smith,
Snedden, (2006), A Faint New Milky Way Satellite in Bootes. Astrophys J, 647, L111.
Zucker, Belokurov, Evans, Kleyna, Irwin, Wilkinson, Fellhauer, Bramich, Gilmore, Newberg, Yanny,
Smith, Hewett, Bell, Rix, Gnedin, Vidrih, Wyse, Willman, Grebel, Schneider, Beers, Kniazev,
Barentine, Brewington, Brinkmann, Harvanek, Kleinman, Krzesinski, Long, Nitta, Snedden,
(2006), A Curious New Milky Way Satellite in Ursa Major. Astrophys J, 650, L41.
Martin, Ibata, Irwin, Chapman, Lewis, Ferguson, Tanvir, McConnachie, (2006), Discovery and
analysis of three faint dwarf galaxies and a globular cluster in the outer halo of the
Andromeda galaxy. Monthly Notices Royal Astron Soc, 371, 1983.
Belokurov, Zucker, Evans, Kleyna, Koposov, Hodgkin, Irwin, Gilmore, Wilkinson, Fellhauer,
Bramich, Hewett, Vidrih, De Jong, Smith, Rix, Bell, Wyse, Newberg, Mayeur, Yanny, Rockosi,
Gnedin, Schneider, Beers, Barentine, Brewington, Brinkmann, Harvanek, Kleinman, Krzesinski,
Long, Nitta, Snedden, (2007), Cats and Dogs, Hair and A Hero: A Quintet of New Milky Way
Companions. Astrophys J, 654, 897.
Irwin, Belokurov, Evans, Ryan-Weber, de Jong, Koposov, Zucker, Hodgkin, Gilmore, Prema, Hebb,
Begum, Fellhauer, Hewett, Kennicutt, Wilkinson, Bramich, Vidrih, Rix, Beers, Barentine,
Brewington, Harvanek, Krzesinski, Long, Nitta, Snedden, (2007), Discovery of an Unusual
Dwarf Galaxy in the Outskirts of the Milky Way. Astrophys J, 656, L13.
These are some disrupted galaxies which are sometimes listed as Local Group Galaxies. The Canis Major Dwarf is (possibly) a remnant of a dwarf galaxy lying within the Milky Way. Andromeda VIII is the disrupted remains of a galaxy in front of the Andromeda Galaxy.
1 2 3 4 5 6 7 8
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Name of Galaxy | Galactic coords|Distance |Diameter| Galaxy | Other | Year of
| l° b° | (kly) | (kly) | Type | Name |Discovery
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Canis Major Dwarf 244.0 -6.0 24±3 20 dIrr? 2003
Andromeda VIII 121.0 -22.2 2500±200 30 dSph 2003
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References: Morrison H, Harding P, Hurley-Keller D, Jacoby G, (2003), Andromeda VIII - a New Tidally Distorted Satellite of M31. Astrophys J, 596, L183. Bellazzini M, Ibata R, Martin N, Lewis G, Conn B, Irwin M, (2006), The core of the Canis Major galaxy as traced by red clump stars. Monthly Notices of the Royal Astron Soc, 366, 865.
