Voyager 1 Fires Up its Old Thrusters After 37 Years
Dec 05 2017
The TCM thrusters were last fired on November 8, 1980, on approach to Saturn, and Voyager 1 used the miniature rocket engines in a more continuous firing mode, not in individual pulses as needed now, NASA officials said.
As NASA announced last Friday, Voyager 1's been using its "attitude control thrusters" (ACMs) for decades, to nudge the probe so that its antenna points at Earth and it can stay in touch.
According toa statement, the Voyager team made a decision to go for a bit of a wildcard, agreeing on an "unusual solution" that involved firing up a set of four backup thrusters, which hadn't been used since 1980. Thankfully, Voyager also has another similar set, called trajectory control maneuver thrusters, that were used in the years after its launch to guide the craft around the various planets it passed on the way out of the solar system. Only one problem: the last time they were used was 37 years ago, in 1980.
And even after Voyager 1 dies - or if we lose contact with it - the spacecraft is ready to achieve great things.
Man, they just don't build 'em like they used to.
"The Voyager flight team dug up decades-old data and examined the software that was coded in an outdated assembler language, to make sure we could safely test the thrusters", said Jones, chief engineer at JPL. But this past Tuesday, engineers fired them up anyway, and after 19 hours of waiting for the results to transmit from Voyager's antenna to Earth, they learned that it actually worked.
Controllers at JPL plan to switch to the TCM thrusters full-time in January, giving Voyager 1's other rocket jets a rest. According to Voyager project manager Suzanne Dodd, the reactivated thrusters should help extend the life of the probe for another "two to three years". To make the change, Voyager has to turn on one heater per thruster, which requires power - a limited resource for the aging mission.
Each Voyager spacecraft carries four TCM thrusters and 12 small attitude control rocket jets, divided into two redundant chains of six thrusters.
Fortunately, the Voyagers are equipped with backup thrusters included with this eventuality in mind. The spacecraft's plutonium generator should produce enough power to keep it operating until around 2025.
This artist's depiction imagines what Voyager 1 looked like when crossing into interstellar space.
Voyager 1 left our solar system in August 2012 and entered interstellar space and is sending data back through NASA's Deep Space Network.