looks like opacity is handled for the entire layer, not just an object in a layer... does that mean each star has to have it's own layer?

I'm just starting with anime studio, I am learing about animation, but I've got a question. I've got star objects on a layer, a moon object on another layer, and a planet object on another layer. I can move the moon around the planet by placing it in different locations at certain keyframes (not ver...