Voyager 2 spacecraft makes its closest approach to Neptune, the last planet in the Solar System at the time, due to Pluto being within Neptune's orbit from 1979 to 1999.

Voyager 2 is a space probe launched by NASA on August 20, 1977, as a part of the Voyager program. It was launched on a trajectory towards the gas giants and enabled further encounters with the ice giants. The only spacecraft to have visited either of the ice giant planets, it was the third of five spacecraft to achieve Solar escape velocity, which allowed it to leave the Solar System. Launched 16 days before its twin Voyager 1, the primary mission of the spacecraft was to study the outer planets and its extended mission is to study interstellar space beyond the Sun's heliosphere.