Known as the Trajectory Correction Manoeuvre (TCM), these thrusters were last used in 1980 when the probe was flying towards the outer reaches of the solar system, passing by planets like Jupiter, Saturn and their moons.
The spacecraft needs to be properly oriented in order to continue communicating back to Earth.
Voyager 1's sibling craft, Voyager 2, is 10.8 billion miles (over 17 million kilometers) from Earth and will likely undergo a similar procedure, though per NASA, its main thruster set is in better condition.
As humanity's first visitor to interstellar space, NASA's Voyager 1 has revealed itself to be a trooper, answering commands that take nearly 20 hours to arrive, and performing routine tasks and transmitting data back (another 20-hour one-way call) to the home planet.
Voyager 1, NASA's farthest and fastest spacecraft, is the only human-made object in interstellar space, the environment between the stars. Voyager Project Manager Suzanne Dodd said the new workaround would extend the life of the Voyager 1 project by two or three years.
Voyager 1 was initially launched to investigate Jupiter, Saturn, and its neighboring moon Titan via flybys.
"The Voyager team got more excited each time with each milestone in the thruster test", said Barber, a JPL propulsion engineer. Back then, the TCM thrusters were utilized in a more constant firing mode; they had never been used in the brief explosions necessary to orient the spacecraft.
NASA's Voyager 1 spacecraft - cruising interstellar space billions of miles from Earth - was back on the right track Friday thanks to thrusters that were fired up for the first time in 37 years. It did. After almost four decades of dormancy, the Aerojet Rocketdyne manufactured thrusters fired perfectly. "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 Todd Barber, a JPL propulsion engineer. Voyager 2 is expected to leave the solar system and enter interstellar space in the next few years. These thrusters fire in small pulses, lasting mere milliseconds, to subtly rotate the spacecraft so that its antenna points at our planet.
The Voyager team now wants to change over to the TCM thrusters in January, during a process where the spacecraft has to switch on a heater for each thruster, which needs power - a scarce resource for this aging mission. The attitude control thrusters now used for Voyager 2 are not yet as diminished as Voyager 1's, however.