It took the Voyager 2 spacecraft a total of 12 years to get from Earth to Neptune. However, the exact amount of time required to travel to Neptune depends on the path and where the planets are in their orbits.
The Voyager 2 spacecraft was launched on Aug. 20, 1977, and it reached Neptune approximately 12 years later, on Aug. 24, 1989. Since Earth and Neptune are moving through space, the distance from one planet to the other constantly changes. The planets can range from 2.7 billion miles apart to 2.9 billion miles apart. A satellite can reach Neptune in the shortest amount of time if Earth and Neptune are on opposite sides of the sun at the time of the satellite's launch.