Oblate spheroid

An oblate spheroid is a very famous shape. It is the shape of the Earth and some other planets. It is like a sphere squashed from the top so the circumference around the poles is less than the circumference around the equator. Shapes of this type are called ellipsoids.

Oblate spheroids have rotational symmetry around an axis from pole to pole.^[1] An example of an oblate spheroid is an M&M.

Many planets, including the Earth and Saturn, are oblate spheroids. The difference between a sphere and the Earth's shape is small, only about one part in 300.

1. ↑ "Oblate Spheroid - from Wolfram MathWorld". Mathworld.wolfram.com. 2009-10-04. Retrieved 2009-10-23.