Engineers are currently trying to solve the issue as the aging spacecraft explores uncharted cosmic territory along the outer reaches of the solar system.

Their exceptionally long lifespans mean that both spacecraft have provided additional insights about our solar system and beyond after achieving their preliminary goals of flying by Jupiter, Saturn, Uranus and Neptune decades ago.

The mission team first noticed the issue November 14, when the flight data system’s telecommunications unit began sending back a repeating pattern of ones and zeroes, like it was trapped in a loop.

While the spacecraft can still receive and carry out commands transmitted from the mission team, a problem with that telecommunications unit means no science or engineering data from Voyager 1 is being returned to Earth.

As both Voyager probes experience new trials, mission team members have only the original manuals written decades ago to consult, and those couldn’t account for the challenges the spacecraft are facing as they age.

In August, the mission team used a long-shot “shout” technique to restore communications with Voyager 2 after a command inadvertently oriented the spacecraft’s antenna in the wrong direction.

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