I believe that producing a star field (long range) and planets and moons ("short range") should be two different layers. As for the star field, I've found this to be useful for my game: http://alexcpeterson.com/spacescape. That can take care of your long range, static star field. It's written in C++ and open source.
As for the "short range" stuff. I've found some sources for solar system simulators, but from my shallow glance, they don't look very generic, if you're wanting to create a different solar system than our own. I put the links at the end.
In reality this shouldn't be too difficult of a task to create a generic system for planets. Study up on your Kepler and you can get some good estimations of planet positions. http://en.wikipedia.org/wiki/Kepler%27s_laws_of_planetary_motion. Probably just stick with simple non-eccentric orbits to start :)
Here's some links for solar system simulators I found.
http://astro.berkeley.edu/~dperley/programs/ssms.html
http://code.google.com/p/solar-system-cpp/