Question

Is the earth a perfect sphere?

Answer 1

The actual shape of the earth is actually an oblate spheroid - a sphere with a bulge around the equator. The Earth is bulged at its equator because it’s rapidly rotating on its axis. The centrifugal force causes the regions at the equator to bulge outward.

High mountain ranges and deep ocean trenches also contribute to Earth's slightly-irregular shape. The shape is also not static. It's always changing. Sometimes these changes are regular, such as daily tides that affect the oceans and Earth's crust. Other changes are irregular and extremely slow, such as the movement of Earth's plates. Sometimes natural disasters can result in sudden changes, such as is the case with earthquakes, volcanic eruptions, and meteor strikes.