OSpiral Galaxy Spinning
spiral galaxies have long,
curved arms. Young stars,
pink nebulas, and dust are
found in the arms.OBarred Spiral Barred
spirals have long, trailing
arms and a central bar. The
center of the bar is thought
to be where stars are born.OElliptical Galaxy These
galaxies are round and made
up of older stars. Many are
found in galaxy clusters.
Most are thought to hold
supermassive black holes.O Irregular Galaxy
Galaxies with no
recognizable shape are
irregular. They are small,
with lots of young stars
and bright nebulas.GALAXY SHAPES
Galaxies
Scattered across the universe are billions of
galaxies, each containing millions or even
billions of stars. They come in many different
shapes and sizes. Modern telescopes can now
see very old galaxies that were born not long
after the birth of the universe.
SHAPES AND SIZES
Some galaxies are “elliptical” or almost round,
like huge balls. Some are spirals, with long,
curved arms. Many small galaxies are
“irregular,” with no special shape. Small
galaxies may contain a few million stars and
measure less than 3,000 light-years across.
The galactic supergiants contain billions
of Suns and are more
than 150,000 light
years across.10 THE WHIRLPOOL
GALAXY This is a huge, well
defined spiral galaxy, 31 million
light-years away. Its smaller
satellite galaxy can be seen.
There are thought to be
supermassive black holes at the
center of most spiral galaxies.SPACE
(c) 2012 Dorling Kindersley. All Rights Reserved.(c) 2012 Dorling Kindersley. All Rights Reserved.