What is the exact launch date of Voyager 1?

Voyager 1 launched on September 5, 1977. NASA sent the spacecraft toward the outer Solar System aboard a Titan IIIE launch vehicle from Launch Complex 41 at Cape Canaveral.

Voyager 1 was launched after its twin, Voyager 2, which left Earth on August 20, 1977. Despite launching later, Voyager 1 followed a shorter trajectory and reached Jupiter and Saturn before Voyager 2 reached those worlds. The spacecraft’s mission was designed to study the outer planets and then continue outward beyond the Sun’s heliosphere.

The launch nearly went wrong. The Titan’s second stage shut down prematurely, leaving propellant unused. The Centaur upper stage compensated with an unusually long burn, delivering enough additional velocity to place Voyager 1 on its intended path. At cutoff, the Centaur was only seconds away from exhausting its fuel.

The date is often confused with August 20, 1977, because that was Voyager 2’s launch date. Voyager 1’s September 5 launch also came 16 days after its twin’s departure.