Download Galaxies and our expanding Universe

Unit 5: Sixth Grade
How big is space?
How big is space?
That is a question man
has been asking since
the beginning of time.
 When your
grandparents were in
school, it was thought
that the Universe was
very small, perhaps only
5000 light years across.
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 A light-year is a unit of
distance. It is the
distance that light can
travel in one year
○ It is about 6 trillion miles
Millions, Billions and Trillions
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One million is a thousand thousands.
One million is a 1 with six zeros after it, denoted by
1,000,000.
One million seconds is about 11 and a half days.
One million pennies stacked on top of each other
would make a tower nearly a mile high.
If you earn $45,000 a year, it would take 22 years to
amass a fortune of one million dollars.
One million ants would weigh a little over six
pounds.<\li>
One million dollars divided evenly among the U.S.
population would mean everyone in the United
States would receive about one third of one cent.
Millions, Billions and Trillions
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Next up is one billion:
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One billion is a thousand millions.
One billion is a 1 with nine zeros after it, denoted by
1,000,000,000.
One billion seconds is about 31 and a half years.
One billion pennies stacked on top of each other would
make a tower almost 870 miles high.
If you earn $45,000 a year, it would take 22,000 years to
amass a fortune of one billion dollars.
One billion ants would weight over 3 tons - a little less
than the weight of an elephant.
One billion dollars divided equally among the U.S.
population would mean that everyone in the United States
would receive about $3.33.
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Millions, Billions and Trillions
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After this is a trillion:
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One trillion is a thousand billions, or equivalently a million
millions.
It is a 1 with twelve zeros after it, denoted by
1,000,000,000,000.
One trillion seconds is over 31 thousand years.
One trillion pennies stacked on top of each other would
make a tower about 870,000 miles high - the same
distance obtained by going to the moon, back to earth,
then to the moon again.
One trillion ants would weigh over 3000 tons.
One trillion dollars divided evenly among the U.S.
population would mean that everyone in the United States
would receive a little over $3000.
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How Big is The Universe?
500 years ago it was
thought that the
Universe was only a
little bit bigger than the
Earth.
 In modern times, with
the power of technology,
we are finally starting to
grasp the immense size
of the Universe, and it is
much bigger than
anyone could have ever
imagined.
 http://www.kidsastronom
y.com/space_size.htm
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Hierarchy of the Universe
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Name
Street Address
City
State
Country
Planet(s)
Terrestrial /Inner Planets---Mercury, Venus, Earth,
Mars
Gaseous/Outer Planets----Jupiter, Saturn, Uranus,
Neptune, and Pluto the Dwarf
Solar System---planets, Sun, asteroid belt
Galaxy---The Milky Way
Universe
Unit 6: Sixth Grade
Galaxies
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Large groups of
stars, dust and gas
are called galaxies.
 Nebulas= large
clouds of dust and
gas
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Galaxies come in a
variety of shapes
and sizes.
The largest galaxies
contain trillions of
stars
Types of Galaxies
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There are many types of galaxies.
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Edwin Hubble, the man who first declared
that the Milky Way is not the only galaxy in
our universe classified galaxies, mostly by
their shapes in the 1920’s
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Galaxies are classified as: Spiral, Elliptical
and Irregular
Spiral Galaxies
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Spiral Galaxies have
a bulge at the center,
and spiral arms.
The arms are made of
gas, dust and new
stars.
 Contain many nebulae
that are forming new
stars
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The Milky Way (our
galaxy) is believed to
be a spiral galaxy
Elliptical Galaxies
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Elliptical galaxies
have very bright
centers and little
dust and gas.
They have no “arms”
Made of mostly old
stars
Look like massive
blobs of stars
Irregular Galaxies
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“Leftover” galaxies.
They are not spiral,
nor are they elliptical
galaxies.
They do not fit into
any classification
group.
Irregularly shaped
Formation of the Universe
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To understand how
the galaxies are
moving, imagine a
loaf of raisin bread
before it is baked.
Inside, each raisin is
a certain distance
from another raisin.
Why happens as the
dough warms and
rises?
Raisin Bread and the Universe
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As the dough warms
and rises, it
expands, and all of
the raisins begin to
move further apart.
No matter which
raisin you observe,
the other raisins are
moving farther away
from it!
Raisin Bread and the Universe
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Scientists believe
that our universe,
like the rising dough,
is expanding.
Think of the raisins
as galaxies.
 As the universe
expands, the galaxies
move farther apart!
The Big Bang Theory
Leading scientific theory
about the formation of
the universe.
 13.7 billion years ago, all
contents of the universe
were compressed under
extreme pressure,
temperature, and density
in a tiny spot.
 Then, the universe rapidly
expanded after a
tremendous explosion.
 The explosion continues
to cause the universe to
expand.
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A Forever Expanding Universe
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As our galaxies move
farther apart, they get
older and stop forming
stars.
Therefore, stars will
age and die, and the
universe will get cold
and dark after many
billions of years.
However, the universe
will continue to
expand forever