Terry LaVerre Snarry age 10, of Midvale, Utah, for the question:

Is gravity the same all over the earth?

The earth's gravity pulls us towards the center of the globe. It is this force which gives us weight. The closer we come to the center of gravity the stronger we feel its force and the more we weigh. The distance from the surface to the center of the earth is its radius and the radius varies from the poles towards the equator.

This is because our earth is not quite a perfect globe. It is a little fatter around its equator waistline. Through the equator, the earth’s diameter is 7926.677 miles. Through the poles the diameter is 7899.988 miles ‑ a difference of 26.689 miles. And radius is half of diameter.

On the equator, then, you are over 13 miles further from the center of gravity than you are on the poles. This, plus centrifugal force, is the reason you weigh slightly morn at the poles than at the equator. So, all over the earth gravity decreases, but only slightly, from the poles towards the equator.