Download galaxy - St John Brebeuf

10.2 Galaxies
Our star, the sun, is one
of 100 - 400 billion stars in
the Milky Way galaxy,
and there are 125 billion
galaxies in the universe!
See pages 356 - 360
A galaxy is a large group of stars.
A nebula is a cloud of gas and dust in space that often produces a new star, or is
the remains of an old star.
http://en.wikipedia.org/wiki/Nebula
Galaxies can be spiral, elliptical or irregular in shape.
How
fast a
galaxy
spins
helps
define
its
shape.
The Milky Way is a barred spiral
galaxy some 100,000–
120,000 light-years in diameter
which contains 100–400
billion stars. It may contain at
least as many planets as
well.[20][21] The Solar System is
located within the disk, about
27,000 light-years away from
the Galactic Center, on the inner
edge of a spiral-shaped
concentration of gas and dust
called the Orion–Cygnus Arm.
http://en.wikipedia.org/wiki/Milky_Way
The Milky Way is the galaxy that contains
our Solar System. This name derives from
its appearance as a dim “milky” glowing
band arching across the night sky, in which
the naked eye cannot distinguish individual
stars. The Milky Way appears like a band
because it is a disk-shaped structure being
viewed from inside.
http://sciencepenguin.com/milky-way-galaxy/
Each galaxy has stars clustered as globular clusters or open clusters.