1. SWBAT
Determine how ancient humans discovered the Earth’s true shape

2. Do Now
Describe how you think the Earth formed.

3. The Earth’s shape
Oblate sphere

5. How do we know the earth is a sphere?
EVIDENCE
Pictures from space
Lunar eclipse-the earth’s shadow on the moon is round

6. How do we know the earth is a sphere?
As a ship sails away from you, the bottom disappears before the top of the sail
The altitude of Polaris (the North Star) increases as you move northward

7. How do we know the earth is a sphere?
The earth is not actually a perfect sphere. It is very slightly wider at the equator. This shape is called an oblate spheroid.
Earth’s circumference:
Equator: 40,076 miles
Poles: ,008 miles

8. Which diagram most accurately shows the cross-sectional shape of the Earth drawn to scale?
(1) (2)
(3) (4)

9. Polaris

10. Begin Spheres lesson

11. TOP 10 REASONS Why We Know the Earth is Round VIDEO

12. Which is a way ancient humans knew the Earth was a sphere
Sailing Ships
Lunar Eclipse
Polaris
All of the above

13. True or False Thumbs Up or Thumbs Down
Polaris is located in the southern hemisphere?
False