The archaic computers aboard Voyager 1 are “stuttering”. Repairing the space probe would be a miracle, NASA claims

NASA's space probe has been suffering for months from a computer anomaly, in what the project manager describes as “the worst” incident in recent history, according to

Computer rendering of the Voyager 1 spacecraft Photo Caltech / NASA / JPL

Voyager 1, mankind's most distant space probe, is having another malfunction – and engineers are having a hard time solving the problem.

The problem is with Voyager 1's 46-year-old Flight Data System (FDS), one of three computers on board. FDS collects data from Voyager's science instruments and retrieves data about its condition and the overall health of the spacecraft. The system is not communicating properly with the telemetry modulation unit, which actually takes the data collected by the system and sends it back to Earth.

This is just the latest in a series of communication problems with Voyager 1, which launched in 1977 shortly after Voyager 2, its twin. In May 2022, the probe suddenly began sending absurd data to the position in space and attitude control (AACS). Suzanne Dodd, project manager for the Voyager missions, described the failure as “normal at this stage”.

It turned out that the data was being transmitted by a faulty computer on the spacecraft, causing it to be read as aberrations by computers on Earth. Engineers solved the problem by sending the telemetry through one of the spacecraft's other computers. In the three months that passed between the problem and its resolution, Voyager 1 traveled 100,000,000 kilometers.

In December 2023, Voyager 1 resumed sending “babblings” again; the telemetry modulation unit started emitting a binary code that seemed to suggest it was stuck. The mission team believes that the problem really lies with the FDS, where the data actually comes from. The Voyager team attempted to resolve the issue by restarting the FDS, but were unsuccessful. The “bubble” persists.

It would be the biggest miracle if we could fix it. I certainly didn't give up“, Dodd told Ars Technica. “There are other things we can try. But this is by far the worst incident since I've been a project manager.”

Voyager 1 is over 24.3 billion kilometers away and continues to travel at just over 61 thousand kilometers per hour. Two months have passed and the issue remains unresolved.

“We can talk to the spacecraft and it can hear us, but it's a slow process given the incredible distance of the spacecraft from Earth”, NASA's Jet Propulsion Laboratory said on Twitter. Each message sent to Voyager takes 22.5 hours to reach the probe, and the reply travels just as long.

The Voyager missions are nearly 50 years old. They served their original purpose decades ago, so every day we get data from them is a bonus. When the two Voyager spacecraft eventually shut down or are abandoned in terms of data collection, they will still be flying toward starry infinity.