Star Apocalypse is the reinvention of the 4X genre. The game is a real time game of intergalactic civilization, using the computation power of modern computers to run advanced simulations on cultural, technological and societal interaction and development.
These pictures roughly show the structure of the current universe. From the galaxy, till the inner solar system level. In between, you'll see Oort Clouds, Stars, Kuiper Belts and Planets. If you would zoom further in, you'd see moons circling around planets.