The sun going down is a constant source of wonder for Natalie. The first few times she asked where it was I told her Jesus put it to bed (the lazy mamma's response!). After her asking over and over and not buying the bedtime bit, I told her.
I went on and on about how the ground we walk on is just a big ball (I figure sphere is too high tech) made of rocks with dirt on top. And that our ball was called Earth and it was really big. We stick to Earth because of gravity. It spins around in circles in space and goes around the sun, a bright shiny ball. When we are facing the sun, it is bright and sunny. When we turn around, it is dark.
I spoke for about 20 minutes on the subject (we had just gotten in the car on the way to work). And this is her summary...
We live on a big ball mama, its name is erf. We stick to it like grabbity tape so we won't fall into the big mud puddle in space.
Hmmm... I think we need to talk a little more! :)