"Our solar system exists inside a heliosphere, a bubble created by the outward flow of the solar wind. The region that separates our system from interstellar space is the heliopause. In between these is the termination shock, where the solar wind slows from supersonic to subsonic speeds." --Credit: JPL / NASA

Below is a time-lapse video recording Voyager 1's approach to Jupiter during a period of over 60 Jupiter days.

The spacecraft are now over 10 billion miles from Earth and are still returning valuable scientific data. They have sufficient electrical power and thruster fuel to operate until around 2020. The equipment on the spacecraft are limited by that of time and it's "most likely" that they will pass silently into interstellar space. At some point, we will no longer receive signals from them and communications will be lost.