ELI5: Explain Like I'm 5

Zonal spherical function

A zonal spherical function is a big word that describes a special type of function that helps people understand and analyze objects that are shaped like a sphere.

When we look at a sphere, we can see that it is perfectly round and symmetrical, which means that it looks the same no matter which way we turn it. If we want to understand more about how a sphere is shaped and how it behaves, we can use math to help us.

A zonal spherical function is a type of math that we can use to describe patterns that we can see on a sphere. Imagine that we are looking at Earth from space, and we can see the lines of longitude and latitude that divide the surface into sections. These lines create a pattern that we can use a zonal spherical function to describe and analyze.

The math that goes into a zonal spherical function is a bit complicated, but it relies on something called Legendre polynomials. These polynomials are like little building blocks that we can use to create the zonal spherical function.

When we put all of these little building blocks together, we end up with a big, complex function that can help us understand things like the gravitational pull of Earth, the way sound travels through the atmosphere, and even the patterns of weather on other planets.

So, a zonal spherical function is a special type of math that helps us understand and analyze round objects like spheres, by breaking them down into smaller parts using Legendre polynomials and creating a big function that describes the patterns we see.