Despite being NASA's "fastest and furthest" spacecraft, however, the last time it fired its main boosters was 37 years ago when it steered past Saturn.
In order to keep the spacecraft running, its thrusters have to function properly, but engineers weren't sure if the small devices were going to work considering they hadn't been used since November 1980.
Fortunately, Voyager 1 seems to refuse to give up the ghost and its backup thrusters have been successfully fired up, even after being left unused for 37 years.
NASA added it will likely do a similar test on the TCM thrusters for Voyager 2, the twin spacecraft of Voyager 1. At 13 billion miles from Earth, there's no mechanic nearby to get a tune-up.
The TCM thrusters were used when Voyager was inside the solar system to boost the probe around Jupiter, Saturn, and the large planets' many moons.
The following day, they learned the thrusters worked perfectly.
Still, the team though the TCM thrusters might suit their purposes, so on November 28, they made a decision to fire them up with 10-millisecond pulses to test if they could be a viable replacement for the almost spent thrusters. The attitude control thrusters now used for Voyager 2 are not yet as diminished as Voyager 1's, however.
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.
Since 2014, engineers have noticed that the thrusters Voyager 1 has been using to orient the spacecraft, called "attitude control thrusters", have been degrading. The team was delighted when the results of their test were resoundingly positive. "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", said Barber, a JPL propulsion engineer. Now, NASA is planning to switch the TCM thrusters on again in January.
NASA believes this will extend the lifespan of the Voyager 1 for another two or three years, with its power finally expected to deplete sometime in 2020.
The Voyager spacecraft were built by JPL, which continues to operate both.