Transcript The Reason for the Seasons

The Reason for the Seasons
___________
Earth _______ on ________
(imaginary line through center of Earth
from North to South Pole)
 Rotation is ___________ clockwise as
seen from North Pole
 Earth spins on its axis like a top
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Polaris
__________ - Axis
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Earth tilt =_________
Axis currently pointed
at Polaris (the North
Star)
___________
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Earth rotates once
every _______ hrs
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The rotation causes
_______ & _________
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Earth’s rotation causes
celestial objects to
appear to move from
east to west in
Northern Hemisphere
Night and Day Map
Just Checking…
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What does it mean when we say the
Earth rotates? ___________________
_______________________________
How would you define or explain the
concept of Earth’s axis? ____________
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________________________________
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Movement of one object around another
Earth _____________ around Sun
 ______________________________
 Earth’s orbit is almost circular rather than
oval shaped but is still referred to as an
_________________________ orbit
 ________days to revolve once around the
Sun (~ a year)
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The imaginary line that runs through
the north and south poles of the
Earth is called the
__________________
Decide weather each example is of
A. Rotation or B. Revolution
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The Earth spinning on it’s axis. ________________
A baseball player running around the infield.
____________
Takes 1 year ________________
A top spinning ________________
Causes day and night. ________________
Takes 24 hours ________________
The moon circling the Earth ________________
Location and Distance in Orbit
Two Primary Reasons for the
Seasons (on Earth)
1. The ____________ of the earth
2. The __________ of Sunlight hitting the earth
Handout available at http://www.uwm.edu/~kahl/CoVis/Seasons/
Seasons
Seasons
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Northern hemisphere tilts _________ Sun
= warmer (Summer)
Seasons
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Northern hemisphere tilts _________ from
Sun = cooler (winter)
Seasons
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In the Spring and the Fall, the tilt of the
Earth is such that the spread of sunlight
shines on the Earth approximately ______
Seasons
Southern hemisphere seasons are
opposite Northern hemisphere seasons
 If its Winter here, then Australia is
having ____________.
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Solstices
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Occur twice yearly when the
Sun is directly over “Tropics”
(23.5°N and 23.5°S Latitude)
 winter solstice = shortest
day of the year for
Northern Hemisphere (Sun
directly over Tropic of
Capricorn-23.5°S-at noon)
 Summer Solstice is the
longest day of the year in
the Northern Hemisphere
 (Sun directly over Tropic of
Cancer-23.5°N-at noon
Equinox
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equal night & day
Occurs twice each
year
Half-way between
solstices
noon sun directly
over equator
Sun will be at its
highest point in our
sky at noon but
never directly
overhead in Texas…
why do you think this
is true?
Your answer should refer to Godley, TX.
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This occurs because the Earth’s axis is
tilted as it moves around the sun.
______________
This occurs when the Northern
hemisphere is tilted towards the sun.
________________
This is when the length of day and night
are equal. __________
The shortest and longest days of the
year when the noon sun is directly
overhead at 23.5 degrees. ___________
This occurs when the Northern
hemisphere is tilted away from the sun.
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A.
B.
C.
D.
E.
Winter
Summer
Solstice
Equinox
All of the
above