NASA is getting really good at squeezing every last bit of life out of its hardware. It recently extended the Dawn spacecraft’s mission over Ceres for a second time, while New Horizons is on its way to check out a small icy body called 2014 MU69 in January 2019. Yesterday, NASA announced that it has successfully fired up four of Voyager 1’s backup thrusters, which haven’t been used since 1980, which should extend its life by a couple of years.

Voyager 1 is the only human-made object flying outside of our solar system, and it’s still communicating with Earth by way of the Deep Space Network, which allows engineers to send it instructions. The probe currently uses its attitude control thrusters to make tiny corrections — firing for only milliseconds at a time — to rotate it to point its antenna towards Earth. However, since 2014, engineers have found that those thrusters have been wearing down, and aren’t as effective.

The JPL’s engineers began to look into alternatives, and found a new way to steer the spacecraft: the probe’s trajectory correction maneuver (TCM) thrusters. These are located on the back of the spacecraft and are identical to the thrusters that they’ve used so far. The last time these thrusters were active was in November 1980, when the probe zipped by Saturn. They haven’t been used since then, and on Tuesday, the Jet Propulsion Laboratory fired them up for the first time, and discovered that they worked. According to Voyager project manager Suzanne Dodd, the reactivated thrusters should help extend the life of the probe for another “two to three years.”

The team will switch over to the TCM thrusters in January, but there is a drawback: they require heaters to operate, which will draw on the probe’s limited power. The team will use the thrusters until they can no longer use the heaters, and will then switch back to the attitude control thrusters that they’ve been relying on. The JPL will also test out the TCM thrusters on Voyager 1’s twin, Voyager 2, although NASA says that that spacecraft’s attitude control thrusters are in better shape.