Transcript:

Okay, which point on the surface of the Earth is furthest away from the centre of the Earth? Now, don't rush into your answer. Instinctively, you might want to say Mount Everest. The top of Mount Everest is 8,828 meters above sea level.

However, there is the equatorial bulge because of the spin of the Earth. The equator is 2 kilometres further away from the centre of the Earth compared to the pole. There is a volcano on the equatorial bulge. It's in Ecuador. It's called Chimborazo, and Chimborazo is 6,268 meters above sea level. However, sea level at Chimborazo is 2 kilometres further out compared to the pole because of the bulge.

So, a person standing on top of Chimborazo will be further out from the centre of the Earth compared to a person standing on the top of Mount Everest. The equatorial bulge completely messes up our estimate.