Voyager 1 lifted off two weeks after its twin, Voyager 2, taking a faster trajectory toward Jupiter and Saturn. Carrying the Golden Record, a phonograph disc encoded with sounds and images representing Earth, the spacecraft returned stunning images of Jovian moons and Saturn's rings before continuing outward. In 2012 it crossed into interstellar space, the farthest-traveling object ever built.
Launched atop a Titan IIIE-Centaur rocket, Voyager 1 was designed for a primary mission of roughly four years, flying past Jupiter and Saturn to study their moons, rings, and magnetic environments. Engineers gave it a faster trajectory than its twin Voyager 2, launched sixteen days earlier, so that Voyager 1 would actually reach Jupiter first.
Bolted to its side is the Golden Record, a gold-plated copper phonograph disc carrying greetings in 55 languages, whale songs, Chuck Berry's 'Johnny B. Goode,' and images of DNA, mountains, and human anatomy, a time capsule assembled by a committee led by Carl Sagan in case any intelligent life ever intercepts it.
The spacecraft's images of Jupiter's volcanic moon Io and Saturn's intricate rings reshaped planetary science in the early 1980s. Long past its planetary mission, Voyager 1 kept transmitting, and in August 2012 it became the first human-made object to cross the heliopause into interstellar space. As of the mid-2020s it still sends faint signals home, powered by a slowly decaying plutonium generator, from more than 15 billion miles away.
Key people: Carl Sagan