In 1977, NASA launched two spacecraft, Voyager 1 and 2, on a grand tour of the solar system and into the mysteries of interstellar space. Attached to each of these probes is a golden phonograph record containing a message for any extraterrestrial intelligence that might encounter it, perhaps billions of years from now. (I co-produced the first terrestrial vinyl release of the Voyager Golden Record.) These two astonishing spacecraft far exceeded their life expectancy and have continued to transmit valuable scientific data back home. Voyager 2 is now trucking through interstellar space more than 12 billion miles from Earth, but NASA is slowly shutting down the probe's various systems to keep others running longer. While the engineers planned to turn off one of Voyager 2's five scientific instruments this year, they've just identified a new way to keep it online for years. From NASA:
In search of a way to avoid shutting down a Voyager 2 science instrument, the team took a closer look at a safety mechanism designed to protect the instruments in case the spacecraft's voltage – the flow of electricity – changes significantly. Because a fluctuation in voltage could damage the instruments, Voyager is equipped with a voltage regulator that triggers a backup circuit in such an event. The circuit can access a small amount of power from the RTG that's set aside for this purpose. Instead of reserving that power, the mission will now be using it to keep the science instruments operating.
Although the spacecraft's voltage will not be tightly regulated as a result, even after more than 45 years in flight, the electrical systems on both probes remain relatively stable, minimizing the need for a safety net. The engineering team is also able to monitor the voltage and respond if it fluctuates too much. If the new approach works well for Voyager 2, the team may implement it on Voyager 1 as well.