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The Local Group of galaxies
The Local Group is a small
cluster of about 40 galaxies, the largest members
of which are the Andromeda Galaxy (M31), a typical
spiral, and our own Galaxy, intermediate in type
between a normal and a barred spiral. This table
itemizes all the established members of the Local
Group. Some small, faint dwarf members may remain
to be discovered.
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Galaxy
|
RA
h m
|
dec
° ’
|
Type a
|
Absolute
magnitude |
Apparent
magnitude |
Distance
from Sun (kpc) |
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|
Andromeda Galaxy (M31)
|
00 42.7
|
+41 16
|
Sb I–II
|
–21.2
|
3.4
|
770
|
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|
Milky Way
|
—
|
—
|
S(B)bc I–II
|
–20.9
|
—
|
—
|
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|
Triangulum Galaxy (M33)
|
01 33.9
|
+30 39
|
Sc II–III
|
–18.9
|
5.9
|
850
|
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|
LMC
M
|
05 24
|
–69 45
|
Ir III–IV
|
–18.5
|
0.2
|
50
|
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|
SMC
M
|
00 53
|
–72 50
|
Ir IV/Ir IV–V
|
–17.1
|
2.0
|
63
|
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|
M32 (NGC 221) A
|
00 42.7
|
+40 52
|
dE2
|
–16.5
|
8.1
|
770
|
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|
M110 (NGC 205) A
|
00 40.4
|
+41 41
|
dE5p
|
–16.4
|
8.4
|
830
|
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|
IC 10 A
|
00 20.3
|
+59 18
|
dIr IV
|
–16.0
|
10.3
|
660
|
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|
NGC 6822 (Barnard’s
Galaxy) M
|
19 44.9
|
–14 52
|
dIr IV–V
|
–16.0
|
8.3
|
500
|
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|
NGC 185 A
|
00 39.0
|
+48 20
|
dE3p
|
–15.6
|
9.0
|
620
|
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|
IC 1613 A
|
01 04.8
|
+02 07
|
dIr V
|
–15.3
|
9.1
|
715
|
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|
NGC 147 A
|
00 33.2
|
+48 30
|
dE5
|
–15.1
|
9.9
|
755
|
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|
Wolf–Lundmark–Melotte
(DDO 221)
|
00 02.0
|
–15 28
|
dIr IV–V
|
–14.4
|
10.6
|
945
|
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|
Fornax Dwarf M
|
02 40.0
|
–34 27
|
dSph
|
–13.1
|
7.7
|
138
|
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|
Pegasus Dwarf (DDO 216, Peg
DIG) A
|
23 28.6
|
+14 45
|
dIr/dSph
|
–12.9
|
12.3
|
760
|
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Sagittarius I Dwarf M
|
18 55.0
|
–30 29
|
dSph
|
–12.7
|
7.7
|
26
|
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|
Sagittarius (Sag DIG)
|
19 30.0
|
–17 41
|
dIrV
|
–12.0
|
13.8
|
1060
|
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|
Andromeda I A
|
00 45.7
|
+38 00
|
dSph
|
–11.8
|
12.9
|
790
|
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|
Andromeda II A
|
01 16.5
|
+33 25
|
dSph
|
–11.8
|
12.6
|
680
|
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|
Cassiopeia Dwarf (Andromeda
VII) A
|
23 26.5
|
+50 42
|
dSph
|
–11.7
|
13.0
|
790
|
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|
Leo A (Leo III, DDO 69)
|
09 59.4
|
+30 45
|
dIrV
|
–11.7
|
12.8
|
800
|
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|
Andromeda VI (Pegasus II) A
|
23 51.8
|
+24 35
|
dSph
|
–11.3
|
13.4
|
775
|
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|
Leo I (DDO 74) M
|
10 08.4
|
+12 18
|
dSph
|
–11.0
|
10.4
|
250
|
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|
Aquarius Dwarf (DDO 210)
|
20 46.9
|
–12 51
|
dIr/dSph
|
–10.9
|
14.2
|
950
|
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|
Andromeda III A
|
00 35.6
|
+36 30
|
dSph
|
–10.2
|
14.4
|
760
|
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|
Cetus Dwarf
|
00 26.2
|
–11 03
|
dSph
|
–10.1
|
14.4
|
775
|
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|
Leo B (Leo II, DDO 93) M
|
11 13.5
|
+22 09
|
dSph
|
–10.1
|
11.5
|
205
|
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|
Phoenix Dwarf M
|
01 51.1
|
–44 27
|
dIr/dSph
|
–9.8
|
13.3
|
405
|
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|
Pisces Dwarf (LGS 3) A
|
01 03.9
|
+21 53
|
dIr/dSph
|
–9.8
|
14.3
|
620
|
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|
Sculptor Dwarf M
|
01 00.1
|
–33 43
|
dSph
|
–9.8
|
10.0
|
88
|
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|
Tucana Dwarf
|
22 41.8
|
–64 25
|
dSph
|
–9.6
|
15.2
|
870
|
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|
Sextans Dwarf M
|
10 13.0
|
–01 37
|
dSph
|
–9.5
|
10.3
|
86
|
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|
Carina Dwarf M
|
06 41.6
|
–50 58
|
dSph
|
–9.4
|
10.7
|
94
|
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|
Draco Dwarf (DDO 208) M
|
17 20.2
|
+57 55
|
dSph
|
–9.4
|
11.0
|
79
|
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|
Andromeda V A
|
01 10.3
|
+47 38
|
dSph
|
–9.1
|
15.9
|
810
|
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Ursa Minor Dwarf (DDO 199) M
|
15 09.2
|
+67 13
|
dSph
|
–8.9
|
10.4
|
69
|
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a dE = dwarf elliptical; dIr = dwarf
irregular; dSph = dwarf spheroidal.
A = companion of the Andromeda Galaxy; M = companion of the Milky Way.
Two additional dwarf companions
of M31, Andromeda VIII and Andromeda IX, were
announced in 2004 but data are still uncertain.
Source: Based on a table by Eva K.
Grebel, John S. Gallagher III and Daniel Harbeck, The
Astronomical Journal,
vol. 125, p. 1928 (April 2003).
Distance of the Sagittarius I
dwarf from L. Monaco et
al., Monthly Notices of the Royal
Astronomical Society,
vol. 353, pp. 874–878 (2004).
Distance of the Cassiopeia
dwarf from I. D.
Karachentsev et al.,
Astronomy and
Astrophysics, vol. 408,
pp. 111–118 (2003).
Distance of the Leo I dwarf
from M.
Bellazzini et al., Monthly Notices of the Royal
Astronomical Society,
vol. 354, pp. 708–712 (2004).
Alternative values for
distances and luminosities can be found in A Catalog of Neighboring Galaxies by Igor D.
Karachentsev et al.,
The Astronomical Journal, vol. 127, pp. 2031–2068,
(April 2004).
Earlier versions of this table
appeared in the 20th edition of Norton’s Star Atlas (Ian Ridpath, ed.) and the Oxford Dictionary of Astronomy (Ian Ridpath, ed.).
Last updated 2006 December
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