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The 'Local Group' is the group of galaxies that includes our galaxy, the Milky Way. The group comprises over 30 galaxies, with its gravitational center located somewhere between the Milky Way and the Andromeda Galaxy. The galaxies of the Local Group cover a 10 million light-year diameter (see 1 E22 m for distance comparisons) and have a binary (dumbbell)^[1] shape. The group is estimated to have a total mass of (1.29 ± 0.14)M_☉.¹
The group itself is one of many within the Virgo Supercluster (i.e. the Local Supercluster).^[2]
The two most massive members of the group are the Milky Way and the Andromeda Galaxy. These two barred spirals each have a system of satellite galaxies.

★ The Milky Way's satellite system consists of Sag DEG, Large Magellanic Cloud, Small Magellanic Cloud, Canis Major Dwarf, Ursa Minor Dwarf, Draco Dwarf, Carina Dwarf, Sextans Dwarf, Sculptor Dwarf, Fornax Dwarf, Leo I, Leo II, Tucana Dwarf, and Ursa Major Dwarf.

★ Andromeda's satellite system comprises M32, M110, NGC 147, NGC 185, And I, And II, And III, And IV, And V, Pegasus dSph, Cassiopeia Dwarf, And VIII, And IX, and And X.
The Triangulum Galaxy, the third largest and only ordinary spiral galaxy in the Local Group, may or may not be a companion to the Andromeda galaxy but probably has Pisces Dwarf as a satellite. The other members of the group are gravitationally secluded from these large subgroups.

Contents

Component galaxies

Map

Galactic bodies

See also

External links

References

Component galaxies

Map

Galactic bodies

Spiral galaxies
name	type	constellation	notes
Milky Way	SBbc	n/a	Second largest galaxy in the group.
Andromeda Galaxy (M31, NGC 224)	SA(s)b	Andromeda	largest member of the group, recently (2006) discovered to also be a barred spiral
Triangulum Galaxy (M33, NGC 598)	SAc	Triangulum	only ordinary spiral galaxy and possible satellite of the Andromeda Galaxy?
Elliptical galaxies
name	type	constellation	notes
M110 (NGC 205)	E6p	Andromeda	satellite of the Andromeda Galaxy
M32 (NGC 221)	E2	Andromeda	satellite of the Andromeda Galaxy
Irregular galaxies
name	type	constellation	notes
Wolf-Lundmark-Melotte (WLM, DDO 221)	Ir+	Cetus
IC 10	KBm or Ir+	Cassiopeia
Small Magellanic Cloud (SMC, NGC 292)	SB(s)m pec	Tucana
Canis Major Dwarf	Irr	Canis Major	satellite of Milky Way
Pisces Dwarf (LGS3)	Irr	Pisces	satellite of the Triangulum Galaxy?
IC 1613 (UGC 668)	IAB(s)m V	Cetus
Phoenix Dwarf	Irr	Phoenix
Large Magellanic Cloud (LMC)	Irr/SB(s)m	Dorado	satellite of Milky Way
Leo A (Leo III)	IBm V	Leo
Sextans B (UGC 5373)	Ir+IV-V	Sextans
NGC 3109	Ir+IV-V	Hydra
Sextans A (UGCA 205)	Ir+V	Sextans
Dwarf elliptical galaxies
name	type	constellation	notes
NGC 147 (DDO 3)	dE5 pec	Cassiopeia	satellite of the Andromeda Galaxy
SagDIG (Sagittarius Dwarf Irregular Galaxy)	IB(s)m V	Sagittarius
NGC 6822 (Barnard's Galaxy)	IB(s)m IV-V	Sagittarius
Pegasus Dwarf (Pegasus Dwarf Irregular, DDO 216)	Irr	Pegasus
Dwarf spheroidal galaxies
name	type	constellation	notes
Boötes Dwarf	dSph	Boötes
Cetus Dwarf	dSph/E4	Cetus
Canes Venatici Dwarf	dSph	Canes Venatici
Andromeda III	dE2	Andromeda	satellite of the Andromeda Galaxy
NGC 185	dE3 pec	Cassiopeia	satellite of the Andromeda Galaxy
Andromeda I	dE3 pec?	Andromeda	satellite of the Andromeda Galaxy
Sculptor Dwarf (E351-G30)	dE3	Sculptor	satellite of Milky Way
Andromeda V	dSph	Andromeda	satellite of the Andromeda Galaxy
Andromeda II	dE0	Andromeda	satellite of the Andromeda Galaxy
Fornax Dwarf (E356-G04)	dSph/E2	Fornax	satellite of Milky Way
Carina Dwarf (E206-G220)	dE3	Carina	satellite of Milky Way
Antlia Dwarf	dE3	Antlia
Leo I (DDO 74)	dE3	Leo	satellite of Milky Way
Sextans Dwarf	dE3	Sextans	satellite of Milky Way
Leo II (Leo B)	dE0 pec	Leo	satellite of Milky Way
Ursa Minor Dwarf	dE4	Ursa Minor	satellite of Milky Way
Draco Dwarf (DDO 208)	dE0 pec	Draco	satellite of Milky Way
SagDEG (Sagittarius Dwarf Elliptical Galaxy)	dSph/E7	Sagittarius	satellite of Milky Way
Tucana Dwarf	dE5	Tucana
Cassiopeia Dwarf (Andromeda VII)	dSph	Cassiopeia	satellite of the Andromeda Galaxy
Pegasus Dwarf Spheroidal Galaxy (And VI)	dSph	Pegasus	satellite of the Andromeda Galaxy
Ursa Major Dwarf	dSph	Ursa Major	satellite of Milky Way
Identification Unclear
name	type	constellation	notes
Virgo Stellar Stream	dSph (remnant)?	Virgo	In the process of merging with the Milky Way
Willman 1	dwarf Spherical galaxy or Globular cluster?	Ursa Major	147,000 light-years away
Andromeda IV	Irr?	Andromeda	probably not a galaxy
UGC-A 86 (0355+66)	Irr, dE or S0	Camelopardalis
UGC-A 92 (EGB0427+63)	Irr or S0	Camelopardalis
Probable non-members
name	type	constellation	notes
GR 8 (DDO 155)	Im V	Virgo
IC 5152	IAB(s)m IV	Indus
NGC 55	SB(s)m	Sculptor
Aquarius Dwarf (DDO 210)	Im V	Aquarius
NGC 404	E0 or SA(s)0-	Andromeda
NGC 1569	Irp+ III-IV	Camelopardalis
NGC 1560 (IC 2062)	Sd	Camelopardalis
Camelopardalis A	Irr	Camelopardalis
Argo Dwarf	Irr	Carina
2318-42	Irr	Grus
UKS 2323-326	Irr	Sculptor
UGC 9128 (DDO 187)	Irp+	Boötes
Palomar 12 (Capricornus Dwarf)		Capricornus	a globular cluster formerly classified as a dwarf spheroidal galaxy
Palomar 4 (originally designated Ursa Major Dwarf)		Ursa Major	a globular cluster formerly classified as a dwarf spheroidal galaxy
Sextans C

See also

★ Groups and clusters of galaxies

★ List of nearest galaxies

★ List of galaxy clusters

★ Local Supercluster

External links

★ The Local Group of Galaxies, SEDS Messier pages

★ A Survey of the Resolved Stellar Content of Nearby Galaxies Currently Forming Stars, Lowell Observatory

★ Updated Information on the Local Group, , Sidney, van den Bergh, The Publications of the Astronomical Society of the Pacific, 2000

References

1. Masses of the local group and of the M81 group estimated from distortions in the local velocity field, Karachentsev, I. D.; Kashibadze, O. G., , , Astrophysics, 2006
2. The Local Supercluster, R. B. Tully, , , Astrophysical Journal, 1982