1. Earth’s Motion, Shape and Spheres

2. How long is one rotation of Earth?
Earth's Motions
How long is one rotation of Earth?
One day
How long is one revolution of Earth?
One year

3. Movement of Stars through the sky Rising and Setting Rotation
of the Sun
Rotation
Rising and Setting
of the Moon
Movement of Stars
through the sky
Revolution
Changing
Constellations
The Seasons

4. Earth's rate of rotation?
How do you calculate
Earth's rate of rotation?
One rotation = 360°
Time for one rotation = 24 hours
360° ÷ 24 = 15°/hr

5. How many degrees did the stars move
from diagram 1 to
diagram 2?
30° (2 hours x 15°)

6. It’s the only one that didn’t move
How can you find
Polaris?
It’s the only one that didn’t move

7. Because Polaris can only been seen in the North
What hemisphere
must you be in?
Why?
Northern
Because Polaris can only been seen in the North

8. What direction must
you be looking?
North

9. What direction do
the stars appear to
move?

10. What causes the
stars appear to move?

11. Evidence for Rotation
Foucault Pendulum
Coriolis Effect

12. Evidence for Revolution
Changing Constellations
Parallax

13. Earth’s Spheres

16. Complete the Atmosphere Foldable

19. Complete the Earth as a Pizza Worksheet

21. Label the Continents and Oceans Activity

22. Shape of the Earth
Earth is an oblate spheroid.
Earth is slightly flattened at the poles and bulges at the Equator.

23. Proof of Earth’s Shape
Ships sail over the curve of the Earth.

24. Proof of Earth’s Shape
During a lunar eclipse, the Earth’s shadow is curved.

25. Proof of Earth’s Shape
Photos from space.

26. it looks very, very, very, very, very, very, very ROUND.
Although the Earth
is oblate,
it looks very, very, very, very, very, very, very ROUND.

27. Size of the Earth
Eratosthenes first determined the size of the spherical Earth, 1500 years before Columbus.

28. Eratosthenes (276 BC – 195 BC) was a Greek mathematician,
poet, athlete, geographer,
astronomer, music theorist
and Mario Cart champion.

29. Eratosthenes was the first person to calculate the circumference of the spherical earth.
7.5o o =
800 km C
ABOUT 3% ERROR
Pretty good, don’t ya think? Over 1600 years before Columbus.

30. 40,008 KM 40,076 KM About 42 miles difference. POLAR CIRCUMFERENCE
EQUATORIAL CIRCUMFERENCE
24,887 MILES
About 42 miles difference.

31. Watch the following video explanation

32. Oblate Spheroid Measurements on earth. Satellite data.
Gravimeter readings.
Gravity readings show that you weigh more at the North Pole than at the Equator, because the poles are closer to the Earth’s center.