Page 118 - DK Children's Encyclopedia

Galaxies SEE ALSO

▸ ▸ Gases p.117
▸ ▸ Milky Way p.167
Galaxies are enormous groups of stars, planets, dust, and ▸ ▸ Physics p.192
gas that are held together by the force of gravity. They ▸ ▸ Shapes p.222
come in different sizes and shapes, including spiral, ▸ ▸ Stars p.242

elliptical, and irregular. ▸ ▸ Universe p.263

Spiral galaxy
New stars form
in the spiral Spiral galaxies are disk-shaped with
arms. spiral arms. They are the most
common type of galaxy. On
average, they contain
more than 100 billion
stars. Our Milky
Way is a spiral
galaxy.

Scientist think
that galaxies are
mostly made of
a material called
“dark matter,” All stars
which we can’t see. rotate around
the center of The middle of the
the galaxy. galaxy bulges
outward.

Elliptical galaxy Irregular galaxy
Elliptical galaxies are Small galaxies that do
rounded in shape, and not have a clear structure
are usually made up of are known as irregular
older stars. They are galaxies. These may be
generally larger than created by two galaxies
spiral galaxies. Elliptical colliding. They contain
galaxies contain lots of lots of young stars,
stars but little gas or dust. dust, and gas.

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