Transcript Movements of the Earth

Movements of the Earth
The Earth’s Motion
Space
in
The Earth Moves Two Ways

Rotating around its axis
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
Once every 24 hours
Revolution around the sun


Once every 365 days
Or one year
The Earth Is Tilted
The earth’s axis is tilted 23.5°
 Orientation of axis doesn’t
change
 Always points towards the
north star

Sun’s Energy Is Uneven
on Earth’s Surface

Causes the
seasons
Summer and Winter
Solstice
Summer solstice
 North pole tilts toward the sun
 June 21 or 22
 First day of summer
 “Longest day of the year”

Summer and Winter
Solstice
Winter solstice
 South pole tilts toward sun
 December 21 or 22
 First day of winter
 “Shortest day of the year”

Autumnal and Vernal
Equinoxes
Equal day and night
 Autumnal equinoxes
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September 22 or 23
First day of fall
Vernal equinoxes
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March 21 or 22, spring
Rotating Earth
Creates day and night
 Rotates west to east
 What do we observe

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Sunrise in the east
Sun travels across the sky
Sunsets in the west
Time Zones
24 hours per
rotation
 Therefore 24 one
hour time zones
around the world
Noon is when the sun is highest
in the center of that zone

Time Zones
How long does it take for the
earth to rotate once?
 How many hours in a day?

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How many degrees in a circle?
360
degrees = 15 degrees
__________
hour
24 hours
Time Zones
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15 degrees wide.
Longitudinal belt with the same
time throughout.
As you go west it gets earlier
subtract an hour.
As you go east it gets later add an
hour.