Philips Atlas of the Universe

The Local Group of Galaxies

T

he only galaxies which are not moving away from us are

the members of what is termed the Local Group. This is

a stable collection of more than two dozen systems, of

which the largest are the Andromeda Spiral, our Galaxy,

the heavily obscured Maffei 1 and the Triangulum Spiral.

Next in order of size come the two Clouds of Magellan,

which are satellites of our Galaxy, and M32 and NGC205,

which are satellites of the Andromeda Spiral. Most of the

rest are dwarfs, some of which are not much more popu-

lous than globular clusters and are much less symmetrical

and well defined.

The Magellanic Clouds are much the brightest galaxies

as seen with the naked eye; they are less than 200,000

light-years away, and cannot be overlooked. Northern

observers never cease to regret that the Clouds are so far

south in the sky – and in fact this is one of the reasons why

most of the large new telescopes have been set up in the

southern hemisphere. Both Clouds show vague indications

of spiral structure, though the forms are not well marked,

and there is nothing of the Catherine-wheel appearance of

the classic spirals; it has even been suggested that the

Small Cloud is a double system, more or less end-on to us.

The Clouds are linked in as much as they form a sort of

binary pair, orbiting each other as they travel round our

Galaxy. They are joined by a bridge of hydrogen gas, and

there is also the ‘Magellanic Stream’, 300,000 light-years

long, reaching over to our Galaxy.

The Clouds are particularly important because they con-

tain objects of all kinds; giant and dwarf stars, doubles and

ATLAS OF THE UNIVERSE

Name Type Absolute Mag. Distance Diameter

1000 l.y.

The Galaxy Spiral 
20.5 – 100

Large Cloud of Magellan Barred spiral 
18.5 169 30

Small Cloud of Magellan Barred spiral 
16.8 190 16

Ursa Minor dwarf Dwarf elliptical 
8.8 250 2

Draco dwarf Dwarf elliptical 
8.6 250 3

Sculptor dwarf Dwarf elliptical 
11.7 280 5

Fornax dwarf Dwarf elliptical 
13.6 420 7

Leo I dwarf Dwarf elliptical 
11.0 750 2

Leo II dwarf Dwarf elliptical 
9.4 750 3

NGC6822 (Barnard’s Galaxy) Irregular 
15.7 1700 5

M31 (Andromeda Spiral) Spiral 
21.1 2200 130

M32 Elliptical 
16.4 2200 12

NGC205 Elliptical 
16.4 2200 8

NGC147 Dwarf elliptical 
14.9 2200 2

NGC1613 Irregular 
14.8 2400 8

M33 (Triangulum Spiral) Spiral 
18.9 2900 52

Maffei 1 Elliptical 
 20 3300 100

SELECTED MEMBERS OF THE LOCAL GROUP

▼ The Small Cloud of

Magellanis a system about

one-sixth the size of our

Galaxy. It is comparatively

close, at about 190,000

light-years, and is a

prominent naked-eye object

in the far south of the sky.

 The Local Group is the

small band of galaxies

to which our Galaxy, the

Milky Way, belongs. It also

contains the Great Nebula

in Andromeda and the

Magellanic Clouds.

Leo I

Sculptor

Leo II

Fornax

LMC

SMC

Milky Way

NGC6822

0.5

1.0

1.5

2.0

2.5 million light years

Wulf Lundmark

NGC185

M33

NGC147

M32

M31

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