It uses small thrusters to guide itself a journey through space, firing them in tiny puffs which last milliseconds at a time.
On Friday, NASA engineers were able to successfully fire Voyager 1's backup thrusters - for the first time in 37 years.
Today's society might be caught up in next year's model when it comes to cars or gadgets, but science fans can stand to appreciate the engineering that went into the Voyager 1 spacecraft.
NASA says the Voyager team is now able to use a set of four backup thrusters which have been dormant since 1980.
Voyager 1 sped past Jupiter and Saturn on its way out of the solar system.
Lo and behold, on Wednesday, Nov. 29, they learned the TCM thrusters worked perfectly - and just as well as the attitude control thrusters.
Because of the success in the attempt to test Voyager 1's TCM thrusters, NASA plans to test the ones on Voyager 2.
But after four decades of exploration which have taken in fly-bys of Jupiter and Saturn, engineers found that the primary thrusters which orient the space probe had severely degraded. The "attitude control thrusters" have been in decline since 2014, and are now wasting more propellant than ever.
"The Voyager team got more excited each time with each milestone in the thruster test". It takes 19 hours, 35 minutes for information to reach Voyager 1 and another 19 hours, 35 minutes for it to report home, so NASA didn't get the results of the data immediately. "The mood was one of relief, joy and incredulity after witnessing these well-rested thrusters pick up the baton as if no time had passed at all", Jones' colleague, Todd Barber, added. The spacecraft has been flying in space for the last 40 years. To make the change, Voyager has to turn on one heater per thruster, which requires power - a limited resource for the aging mission. The attitude control thrusters now used for Voyager 2 are not yet as diminished as Voyager 1's, however.
Voyager 1 is in interstellar space and Voyager 2 is now in the "Heliosheath" - the outermost layer of the heliosphere where the solar wind is slowed by the pressure of interstellar gas.