I'm looking for a rather oddball piece of software that may or may not exist. What I want to do is generate an image of what the sky would look like from a hypothetical extrasolar planet with configurable sky features--for example, a planet with a small ring and a couple of moons with X orbital inclination from Y latitude at Z:00 o'clock. Using a solar system simulator that can show the sky as seen from, say, Saturn could sort of fudge it, but I'm hoping for something a little more configurable. A bunch of Googling turned up nothing useful. Anybody know if such software exists?