1. The Reason for the Seasons

2. ___________ Earth _______ on ________ (imaginary line through center of Earth from North to South Pole) Earth _______ on ________ (imaginary line through center of Earth from North to South Pole) Rotation is ___________ clockwise as seen from North Pole Rotation is ___________ clockwise as seen from North Pole Earth spins on its axis like a top Earth spins on its axis like a top

3. __________ - Axis Earth tilt =_________ Earth tilt =_________ Axis currently pointed at Polaris (the North Star) Axis currently pointed at Polaris (the North Star) Polaris

4. ___________ Earth rotates once every _______ hrs Earth rotates once every _______ hrs The rotation causes _______ & _________ The rotation causes _______ & _________ Earth’s rotation causes celestial objects to appear to move from east to west in Northern Hemisphere Earth’s rotation causes celestial objects to appear to move from east to west in Northern Hemisphere

5. Night and Day Map

6. Just Checking… What does it mean when we say the Earth rotates? ___________________ What does it mean when we say the Earth rotates? ___________________ _______________________________ _______________________________ How would you define or explain the concept of Earth’s axis? ____________ How would you define or explain the concept of Earth’s axis? ____________ ________________________________ ________________________________

7. _______________ Movement of one object around another Movement of one object around another Earth _____________ around Sun Earth _____________ around Sun ______________________________ ______________________________ Earth’s orbit is almost circular rather than oval shaped but is still referred to as an _________________________ orbit 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) ________days to revolve once around the Sun (~ a year)

8. The imaginary line that runs through the north and south poles of the Earth is called the __________________ The imaginary line that runs through the north and south poles of the Earth is called the __________________

9. Decide weather each example is of A. Rotation or B. Revolution The Earth spinning on it’s axis. ________________ The Earth spinning on it’s axis. ________________ A baseball player running around the infield. ____________ A baseball player running around the infield. ____________ Takes 1 year ________________ Takes 1 year ________________ A top spinning ________________ A top spinning ________________ Causes day and night. ________________ Causes day and night. ________________ Takes 24 hours ________________ Takes 24 hours ________________ The moon circling the Earth ________________ The moon circling the Earth ________________

10. Location and Distance in Orbit

11. http://www.uwm.edu/~kahl/CoVis/Seasons/Handout available at 1.The ____________ of the earth 2.The __________ of Sunlight hitting the earth Two Primary Reasons for the Seasons (on Earth)

12. Seasons

13. Seasons Northern hemisphere tilts _________ Sun = warmer (Summer) Northern hemisphere tilts _________ Sun = warmer (Summer)

14. Seasons Northern hemisphere tilts _________ from Sun = cooler (winter) Northern hemisphere tilts _________ from Sun = cooler (winter)

15. Seasons In the Spring and the Fall, the tilt of the Earth is such that the spread of sunlight shines on the Earth approximately ______ In the Spring and the Fall, the tilt of the Earth is such that the spread of sunlight shines on the Earth approximately ______

16. Seasons Southern hemisphere seasons are opposite Northern hemisphere seasons Southern hemisphere seasons are opposite Northern hemisphere seasons If its Winter here, then Australia is having ____________. If its Winter here, then Australia is having ____________.

17. Solstices Occur twice yearly when the Sun is directly over “Tropics” (23.5°N and 23.5°S Latitude) 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

18. Equinox equal night & day equal night & day Occurs twice each year Occurs twice each year Half-way between solstices Half-way between solstices noon sun directly over equator 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? 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?

19. Your answer should refer to Godley, TX. This occurs because the Earth’s axis is tilted as it moves around the sun. ______________ 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 occurs when the Northern hemisphere is tilted towards the sun. ________________ This is when the length of day and night are equal. __________ 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. ___________ 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. ___________ This occurs when the Northern hemisphere is tilted away from the sun. ___________ A. Winter B. Summer C. Solstice D. Equinox E. All of the above

20. Based on this Night and Day Map… What season do you think it is in Godley? What season do you think it is in Godley? What time do you think it is in Godley? What time do you think it is in Godley?