How many planets did Voyager 1 fly by?

Voyager 1 flew by two planets: Jupiter and Saturn. These encounters formed the core of its original planetary mission and placed the spacecraft on a trajectory toward interstellar space.

Voyager 1 reached Jupiter in March 1979, making close observations of the planet’s atmosphere, magnetic environment, rings and major moons. It then continued to Saturn, reaching the Saturnian system in November 1980. The spacecraft’s trajectory was adjusted during the Saturn encounter, sending it northward out of the plane in which most planets orbit.

Voyager 1 also flew close to Titan, Saturn’s largest moon. Titan is not a planet, so it does not increase the answer to this question. The mission team chose the Titan encounter over a planned Pluto flyby because Titan was known to possess a substantial atmosphere.

Voyager 2 visited four planets—Jupiter, Saturn, Uranus and Neptune—which is the source of another common mix-up. Voyager 1 visited only Jupiter and Saturn, although it made observations of numerous moons and other objects along the way.