Solar system

A solar system (or star system) is an area of space located around a star, and contains all of the objects that orbit that star, ie planets, moons, asteroids, and nebulae, which are all held in place in the star's gravity well.

The size of a solar system is usually dictated by the extent of a star's gravitational pull on the system. The edge of a system is usually made up of an Oort cloud, which is a layer of ice and debris. (ST reference book: Star Trek: Star Charts).