<P> Voyager 1 is a space probe launched by NASA on September 5, 1977 . Part of the Voyager program to study the outer Solar System, Voyager 1 launched 16 days after its twin, Voyager 2 . Having operated for 40 years, 11 months and 24 days as of August 29, 2018, the spacecraft still communicates with the Deep Space Network to receive routine commands and return data . At a distance of 142.31 astronomical units (2.1289 × 10 km; 1.3229 × 10 mi) (21.289 billion kilometers; 13.229 billion miles) from the Sun as of June 4, 2018, it is the spacecraft most distant from Earth . </P> <P> The probe's objectives included flybys of Jupiter, Saturn, and Saturn's largest moon, Titan . While the spacecraft's course could have been altered to include a Pluto encounter by forgoing the Titan flyby, exploration of the moon, which was known to have a substantial atmosphere, took priority . It studied the weather, magnetic fields and rings of the two planets and was the first probe to provide detailed images of their moons . </P> <P> After completing its primary mission with the flyby of Saturn on November 12, 1980, Voyager 1 became the third of five artificial objects to achieve the escape velocity that will allow them to leave the Solar System . On August 25, 2012, Voyager 1 became the first spacecraft to cross the heliopause and enter the interstellar medium . </P> <P> In a further testament to the robustness of Voyager 1, the Voyager team completed a successful test of the spacecraft's trajectory correction maneuver (TCM) thrusters on November 28, 2017 . The last time these backup thrusters were fired up was in November 1980 . Voyager project manager Suzanne Dodd anticipates that successful use of the TCM thrusters will extend the Voyager mission by an additional "two to three years". </P>

When did voyager 1 leave our solar system