Seasons

1
Seasons

• What do you know about seasons?

2
Seasons

• A season is one of the major divisions of the
  year, generally based on yearly periodic changes
  in weather.

3
Seasons

• Seasons result from the yearly revolution of the
  Earth around the Sun and the tilt of the Earth's
  axis.

4
Rotation vs. Revolution

• Rotation is the spin of an object about its axis.
• The Earth rotates once a day (once every 24
  hours).
• Revolution is the orbit of one object around
  another.
• The Earth revolves around the Sun every 365.26
  days.

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How does the 23.5 degree tilt of the Earths axis
affect SEASONS?
The Earths Axis is ALWAYS TILTED the SAME
direction. Sometimes the EARTHS AXIS is TILTED
AWAY from the sun. (thats Winter in the Northern
Hemisphere) Sometimes the EARTHS AXIS is TILTED
TOWARDS the sun. (THE SUMMER in the Northern
Hemisphere) When the EARTHS AXIS is simply on
its side Thats Spring or Fall.
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Solstices
Links to animations below
Winter solstice
Summer solstice
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Equinox
Equinox animation
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Check out these video clips!

• http//www.youtube.com/watch?vDuiQvPLWziQ
• http//www.youtube.com/watch?vtaHTA7S_JGkfeature
  related

• http//www.youtube.com/watch?vtaHTA7S_JGkfeature
  related
• http//www.youtube.com/watch?vO9hawBb3wbk

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What do you think.rotation or revolution

• What causes day and night?
• What happens when the Earth completes one
  revolution?
• What happens when the Earth completes one
  rotation?
• What does the Earth revolve around?

10
Summer vs. Winter

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What do you observe in this picture?

• .

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Some cool facts to help you remember.

• Sol (from the word Solstice) sun
• Stice ( from the word Solstice) standing still
• Equ- (from the word Equinox) equal
• Nox (from the word Equinox) night
• How can this help you to remember the seasons?

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Do you know

• What month does the solstice occur?
• What month does the equinox occur?

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Seasons

• During June, July, and August the northern
  hemisphere is exposed to more direct sunlight
  because the northern hemisphere faces the sun.
• How does this affect us?
• The same is true of the southern hemisphere in
  December, January, and February.
• Something to think about
• Which hemisphere do we live in? When were having
  summer, what do you think is happening in the
  other hemisphere?

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Suns Rays
What season does this picture reflect in the
Northern Hemisphere? What is the first day of
this season called?
16
Seasons
What observations can you make about the tilt of
the axis in each phase?
17
What season is this in the Northern Hemisphere?
Include the SUN, the EARTH, the TILT OF THE AXIS,
and the EQAUTOR
18
What would happen
if the Earth wasnt tilted on its axis?
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All 4 SEASONS- Can you explain this picture?
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Get Ready for Tim and Moby!

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