Orbit and Gravity Movement Blueprint

Hey, this looks fantastic.

Just wondering, if I set up a planet to orbit the sun, can I have a moon orbit the planet? And would the planets/moons orbits be affected by the gravitational pull of other planets/moons? Is everything pre-calculated, or if I suddenly dropped in another planet (in real time), would the planets already in the map be affected? I hope I made this all make sense.

Thanks!