Okay kiddo, imagine you have a big cake, but you want to know how much of it is chocolate and how much is vanilla. One way to do that is to cut a small slice and see what it looks like. But what if the cake is really big and you can't cut little slices all day? That's where something called the Chandrasekhar-Kendall function comes in.
Basically, this function helps you understand how much of something is in a really big thing, like our cake. Scientists and mathematicians use it to figure out how much of a certain substance is in a large body, like how much iron is in the Earth's core.
It works by looking at the way that light or a certain signal changes as it passes through the thing you're interested in. For example, if you shine a light through the cake, some of it will go through the vanilla and some will go through the chocolate. The light might also bounce off of things or get absorbed at different rates in different parts of the cake.
The Chandrasekhar-Kendall function takes all of these things into account and helps you make a really good guess about how much of the thing you're interested in is in the whole cake. It's like magic, but with numbers!