Solar System - Farthest Regions

Farthest Regions

The point at which the Solar System ends and interstellar space begins is not precisely defined, since its outer boundaries are shaped by two separate forces: the solar wind and the Sun's gravity. The outer limit of the solar wind's influence is roughly four times Pluto's distance from the Sun; this heliopause is considered the beginning of the interstellar medium. However, the Sun's Hill sphere, the effective range of its gravitational dominance, is believed to extend up to a thousand times farther.