Some Jewish writings explicitly describe 3 to 7 different “floors” of the sky. As soon as you start building apartment complexes in the sky, you know there are going to heavenly building codes to go by … so, if you
have a layer of firmament into which the stars are afixed… and above that layer is a cosmic ocean… and above that layer there is yet another “floor” or “ceiling”… the only place anyone can fit a “dome” is the very last or top layer, right?
Jonathan Burke found this image of a fairly flat sky even with Egyptian perspectives!: