NASA’s two Voyager spacecraft, launched in the 1970s, have passed beyond the orbit of Pluto and into interstellar space, making them the most distant man-made objects to exist in the universe. However, as you’d expect from technology that is nearly 50 years old, the pair of probes have had their share of technical difficulties in their time. But now, NASA has announced that it is back in contact with Voyager 1, around five months after communications with the spacecraft were disrupted. The remarkable pair of explorers continue out into the depths of space to fight another day.
The recent issues with Voyager 1 came to a head in November of last year, when NASA announced that it was experiencing communications issues. Although the instruments and most systems appeared to be working as expected, there was a problem with one of the onboard computers called the flight data system (FDS), which meant that science and engineering data was not being sent back to Earth correctly.
The FDS is responsible for packaging up data from the spacecraft (both engineering data, which is about the health of the spacecraft itself, and science data, which is about the readings it takes using its instruments) and relaying this data back to Earth. A single chip in the FDS had failed, which caused the FDS to malfunction and not send data correctly.
Replacing a chip in a spacecraft that is around 15 billion miles away isn’t possible. So the engineers at NASA’s Jet Propulsion Laboratory had to come up with a way to route data around the compromised chip. But on hardware this old, there aren’t a lot of resources to spare. There was no one location that could hold the code from the chip, so it had to be divided up and stored in different locations around the FDS.
The first portion of the new code was sent out to Voyager 1 on April 18, but the probe is so far from Earth that it takes nearly a full day for the signal to arrive there, and another full day for the response to arrive back at Earth. But there was good news: On April 20, the team received health and status information from the spacecraft for the first time since November 2023.
Now, the team will continue sending updates to the software to deal with the FDS issue, and will hopefully be able to access science data again soon.