Lesson 3: Earth's Shape

Oblate Spheroid
1. oblate spheroid - a sphere that is slightly flattened
2. Earth is slightly flattened at the poles
3. Earth bulges as bit at the equator
4. Because of Earth's rotation, Earth is an oblate spheroid
Looks Flat
1. Because it is very large
Round
1. Photographs of Earth all show Earth's spherical shape
2. We notice the changing position of the sun and stars as we move great distances over Earth
3. An object's weight depends on distance to Earth's core, since weight doesn't change in different places, each point on earth is equidistant to to core
Diameter and Circumference
1. Circumference - the distance around a circle
  1. Equatorial Circumference of Earth = 40,076 kilometers
  2. Polar Circumference of Earth = 40,008 kilometers
2. Diameter - the distance through the center of an object
  1. Polar Diameter of Earth = 12,714 kilometers
  2. Equatorial Diameter of Earth = 12,756 kilometers
3. If Earth were a perfect sphere the Equatorial and Polar values would be equal

Resource summary

	Created by Dana Balin over 3 years ago

	Copied by Dana Balin over 3 years ago