Voyager 1 Instruments Return to Service After Computer Malfunction

NASA’s Jet Propulsion Laboratory (JPL) has confirmed that four scientific instruments aboard the Voyager 1 spacecraft are once again transmitting data.

This marks the first time they have done so since a computer malfunction last November. The instruments, which measure plasma waves, magnetic fields, and particles in interstellar space, had been offline due to a corrupted memory chip. The malfunction, which occurred in November 2023, caused the spacecraft to send back garbled data.

A dedicated team of engineers, known as a "tiger team," traced the issue to a corrupted memory chip in one of the spacecraft’s computers. They successfully reprogrammed the software to bypass the faulty chip, restoring communication with Voyager 1 in April.

"The tiger team was able to reprogram and relocate that code, first for the engineering portion of the data modes coming from the spacecraft. We are now getting science data back from all four Voyager 1 science instruments." - Linda Spilker, Voyager Project Scientist

Historic Update

Voyager 1 was launched in 1977 and, along with its twin, Voyager 2, has been on a mission exploring the outer planets and beyond.

"This is the first flight software update made to a spacecraft in interstellar space. The last time we really did much with the flight software was prior to launch." - Linda Spilker, Voyager Project Scientist

The primary challenge for the continued operation of the Voyager spacecraft is declining power levels. Each spacecraft loses about four watts of power annually due to the decay of their plutonium-238 power supplies and the degradation of thermocouples that convert heat into power. To manage this decline, controllers have turned off nonessential systems, including heaters that had maintained the temperature of instruments and other components.

"What’s happening is that the spacecraft is becoming cold, so we have both a power concern as well as a thermal concern...With a little bit of luck, it might be possible to continue the Voyager spacecraft taking data out to the 2030s," - Linda Spilker, Voyager Project Scientist

If Voyager 1 reaches 2035, it will be approximately 200 astronomical units (about 30 billion kilometers) from the sun. Currently, Voyager 1 is more than 24 billion kilometers from the sun.

The immediate goal for the mission team is to keep the spacecraft operational until 2027, which marks the 50th anniversary of the launch of both Voyager spacecraft.

The return of Voyager 1’s scientific instruments to operational status came just two days after the announcement of the passing of Ed Stone, who served as Voyager’s project scientist from the mission’s inception in 1972 until his retirement in 2022. Stone, a renowned physicist and former director of Caltech, was instrumental in the Voyager mission’s successes.

"Ed Stone would often say during the planetary flyby phase that we had a rare opportunity with the alignment of the planets and we seized it. I would add that both Voyagers still have rare opportunities, and Ed will continue to seize them." - Linda Spilker, Voyager Project Scientist

The successful reactivation of Voyager 1’s instruments not only honors Stone’s legacy but also promises to extend the remarkable journey of these pioneering spacecraft as they continue to explore the mysteries of interstellar space.