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Outreach:
Introduction
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 Our galaxy is called the Milky
Way. It is a spiral galaxy about 100,000
light-years across. It contains at least 200 billion stars, possibly as
many as 400 billion. From Earth, the Milky Way looks like a streak of
stars across the sky. The Sun is in one of the  spiral
arms, about
two-thirds of the way out from the centre of the galaxy.
The Milky Way
is
a member of the Local Group of at least 30 galaxies. It is over ten million light-years
across.
Of these galaxies, the
largest is
Andromeda, followed by the Milky Way. Both of these
galaxies have
satellite
galaxies
orbiting them; the Milky Way has 14 satellites, including the Large and Small
Magellanic Clouds.
The Magellanic
System consists
of the
Large and Small Magellanic
Clouds. These are two small irregular
galaxies which orbit our galaxy, the Milky Way. They
can be seen from the southern hemisphere at night.
The Clouds are important to astronomers because they
contain
stars of
all types and all ages, all found at about the same distance away from
Earth.  This
means that it is
easier for astronomers to compare the
stars.
The Large
Magellanic
Cloud is the
fourth largest member of our Local
Group of 30 galaxies, after Andromeda, the Milky Way and Triangulum. It
is 160,000 light-years away from the Milky Way and about fifteen
thousand light-years across.
The Small Magellanic
Cloud is 200,00
light-years away and contains a few hundred million stars. It is one of
the furthest objects that can be seen with the naked eye.
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