Final answer:
The sun's gravitational influence extend as far as the Oort cloud, which is located beyond Pluto.
Step-by-step explanation:
The sun's gravitational influence extends as far as the Oort cloud.
It is possible to calculate that a star's gravitational sphere of influence-the distance within which it can exert sufficient gravitation to hold onto orbiting objects-is about one third of its distance to the nearest other stars. Stars in the vicinity of the Sun are spaced in such a way that the Sun's sphere of influence extends a little beyond 50,000 AU, or about 1 light-year. At such great distances, however, objects in orbit about the Sun can be perturbed by the gravity of passing stars. Some of the perturbed objects can then take on orbits that bring them much closer to the Sun (while others might be lost to the solar system forever).