Learn the rotation of the Earth

1. PREPARED BY: TYPE YOUR NAME HERE

2.  Using models, relate:
 1 the tilt of the Earth to the length of daytime
 2 the length of daytime to the amount of energy received
 3 the position of the Earth in its orbit to the height of the Sun
in the sky
 4 the height of the Sun in the sky to the amount of energy
received
 5 the latitude of an area to the amount of energy the area
receives
 6 tilt of the Earth and the seasons

3. What are the
two motions
of the earth?
Rotation & Revolution
How long
does it take
the earth to
rotate?
24 hours (one day) to
rotate (spin) once on its
axis

4. How long does
it take the
earth to revolve
around the
sun?
365 ¼ Days (one year) to
complete one revolution
around the sun

5. What does the
earth’s rotation
cause?
As the earth rotates (counter-clockwise), part of
it faces the sun and the rest of it faces away from
the sun and is in darkness.
Day & Night

6. Why does the
length of the day
change
throughout the
year?
Due to the tilt of the earth’s
axis (23.5° angle)
Example: When the
North Pole is tilted toward
the sun, the Northern
Hemisphere has longer
days and shorter nights
= SUMMER

7. Where does the
north pole of the
earth always
point?
Towards Polaris
(A.K.A. The North Star)

8. Where does
the sun and
moon appear
to rise and set?
•The sun, moon, & stars all
appear to rise in the East and
set in the West
•Due to the counter-clockwise
rotation of the Earth

9. How does the rotation of the earth affect the
motion of the winds & ocean currents?
Northern Hemisphere:
The Earth rotates
Counterclockwise
Causing: winds and
ocean currents to be
deflected to the Right.
Southern Hemisphere:
The Earth rotates
Clockwise.
Causing: winds and
ocean currents to be
deflected to the Left.

10. What is the deflection
(of winds & water) at
Earth’s surface called?
Observe an animation of the Coriolis effect over Earth's
surface.
The Coriolis Effect.

12. What evidence
shows that the
earth rotates?
1) Coriolis Effect
2) Satellite Pictures
3) Pictures from the earth
of the night sky would show
arcs of light, or star trails,
from the motions of the
earth.

14. What evidence
shows that the
earth revolves
around the
sun?
1) Constellations (patterns
of stars) appear to move
Observing the Sky: Motion of the Sun and
Stars - The Night Sky
2) The Sun appears to be larger
during the winter months and
smaller as summer approaches.
• Perihelion – earth closest to the
sun
•Aphelion – earth furthest away
from the sun

18.  Why do we have day and night on earth?
 If the earth’s axis was not tilted every where on earth
would have how many hours of daylight and
darkness?
 Why does the sun appear to rise in the east and set in
the west?
 What would happen if the earth did not rotate?

19. • What is the Coriolis Effect?
• How do we know that the Earth
rotates?
• Which motion of the earth causes day
and night?
• How do we know the earth revolves
around the sun?

20. The hemisphere that is
tilted toward the sun gets:
1. more hours of sunlight
&
2. more direct sun
What causes
summer?

22. The combination of more direct
sunlight & longer days causes the
Earth’s surface and atmosphere to
receive more heat from the sun.
Summer and winter are not affected
by the Earth’s distance from the sun.

23. Which day of the
year gives us
the most
sunlight?
Summer:
a) Begins in the Northern
Hemisphere on June 21
b) Called the Summer
Solstice “Sun Stop”
c) The most sunlight is
received on this day
d) Length of daylight varies
depending on your distance
from the equator

24. Which day of the
year is the
shortest?
Winter:
a) Begins in the Northern
Hemisphere on Dec 21st
b) Called the Winter Solstice
c) The day of the year when
the Northern Hemisphere
gets the least amount of
sunlight

25. What is an
equinox?
a) 2 days of the year the sun
shines directly overhead on
the equator:
Spring equinox is March, 21st
&
Fall equinox is September,
23rd
b) During this time all places on
earth have 12 hours of
daylight and 12 hours of
darkness.

28. If it is summer
in the northern
hemisphere,
what season is
it in the
southern
hemisphere?
The Northern and
Southern hemispheres
have opposite seasons.
Earth: What causes the
Seasons?

29.  During the year when is the earth closer to the sun?
 Why do we have seasons on earth?
 If the North Pole is having summer, what season is the
South Pole having?

30. What are the
time zones?
The earth is divided into
24 time zones
(called standard time)
WHY 24?
USA has 4 time zones:
1. EASTERN STANDARD TIME
2. CENTRAL STANDARD TIME
3. MOUNTAIN STANDARD TIME
4. PACIFIC STANDARD TIME

31. As you move west the time in each zone is
one hour earlier than in the previous zone.
What is the
international
date line?
The boundary formed where
the 1st and 24th time zones
meet
What happens when you cross
the International Date Line?
How could you travel back in
time?

32. 10 pm
9 pm
8 pm
7 pm
Eastern
Central
Mountain
Pacific