The last time the TCM thrusters were used was on November 8, 1980, during Voyager 1's encounter with Saturn, after which, they were not needed because there were no more planetary encounters.The experts searched up old date from years ago and studied the software coded in an assembler language, which was outdated, to ensure that the thrusters could be worked safely.
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 and 2 - both launched in 1977 - have been exploring farther-flung planets in our solar system.
Voyager 1, NASA's farthest and fastest spacecraft, is the only human-made object in interstellar space, the environment between the stars. We've learned about Jupiter's moons, Saturn's rings, Neptune's winds - all thanks to Voyager 1. This maneuver used thrusters that haven't been fired since 1980, and could keep Voyager 1 sending back communications for another two or three years.
For the first time since 1980, NASA activated Voyager 1's backup thrusters. Over the past four decades, as it flew past Jupiter and Saturn and eventually out into the vast reaches of space, it's been using tiny thrusters to position its antenna so it can communicate with Earth.
NASA fired the thrusters for the Voyager, 37 years after they had last been used, according to a new report from the agency.
The Voyager team chose to try using the TCM thrusters, which were created to accurately point the spacecraft as it passed Jupiter and Saturn and their moons.
After reviewing decades-old data and software "that was coded in an outdated assembler language", JPL engineers, led by JPL Chief Engineer Chris Jones, determined it was safe to attempt to fire them.
The MR-103 thrusters, provided by Aerojet Rocketdyne, are created to fire in pulses to rotate the spacecraft and keep its 12-foot (3.7-metre) antenna pointed at Earth, but engineers have noticed more firings were needed recently, indicating the jets were losing some of their performance. The mood was one of relaxation, joy and wonder after observing these well-rested thrusters pull up the baton as if no time had moved at all. The plan right now is to switch to the TCM thrusters in January. Voyager 1 was already operating on its backup branch of attitude control thrusters.
Voyager 1 was launched on September 5, 1977. It's expected to enter deep space within the next few years.