Back in November of 2023 the space probe Voyager 1 stopped sending certain signals back to Earth. Many believed that the probe had been hijacked by machine intelligences of alien origin who wanted to make the probe self-aware, build a massive ship around the probe, and send it back to Earth, only to be confronted by the crew of the U.S.S. Enterprise, who would discover the transformed probe’s purpose only through the telepathic heroics of Mr. Spock. No wait, that’s the plot for Star Trek: The Motion Picture. What really happened back in November was both more banal and far more fascinating. Here’s more from Centauri Dreams:
What a complex and fascinating realm long-distance repair is. I naturally think back to Galileo, the Jupiter-bound mission whose high-gain antenna could not be properly deployed, and whose data return was saved by the canny use of the low-gain antenna and a revised set of parameters for sending and acquiring the information. Thus we got the Europa imagery, among much else, that is still current, and will be complemented by Europa Clipper by the start of the next decade. The farther into space we go, the more complicated repair becomes, an issue that will force a high level of autonomy on our probes as we push well past the Kuiper Belt and one day to the Oort Cloud.
In the case of Voyager 1, the problem was traced to the aforesaid flight data subsystem, which essentially hands the data off to the telemetry modulation unit (TMU) and radio transmitter. Bear in mind that all of this is 1970s era technology still operational and fixable, which not only reminds us of the quality of the original workmanship, but also the capability we are developing to ensure missions lasting decades or even centuries can continue to operate. The Voyager engineers gave a command to prompt Voyager 1 to return a readout of FDS memory, and that allowed them to confirm that about 3 percent of that memory had been corrupted.