The routes the Voyager spacecraft have
taken since launch. Not to scale.

In an effort to keep Voyager-2 operating with its dwindling power supply into 2027, engineers have successfully completed a complete major reconfiguration of its instruments and power use.

Nicknamed the “Big Bang,” the effort involved simultaneously turning off certain powered devices and substituting them with lower-power alternatives while ensuring the spacecraft remains warm enough to operate.

The Voyagers get their power from radioisotope thermoelectric generators, devices that convert heat from decaying plutonium into electricity. Due to the plutonium supply continually depleting, both probes lose about 4 watts of power each year. After almost a half-century since launch, the spacecraft power margins have grown razor thin, requiring the team to conserve energy by shutting off non-essential devices and systems.

Since 2024, the dwindling power supply has forced the mission to turn off two science instruments on each of the Voyager spacecraft (each spacecraft has 10 instruments; others had been turned off previously because they were only used for the mission’s planetary encounters). Without the Big Bang activity, the mission would have had to turn off another instrument on Voyager 2 before the end of 2026. The savings should provide power to keep its three instruments operating for at least an extra year.

This reboot was risky, so engineers did it first on Voyager-2 because it is closer to Earth. They will now plan a similar reboot on Voyager-1. The goal with both is to keep both not only operating but still gathering science data until at least 2027, the fiftieth anniversary of their launch. At present both spacecraft likely have the longest continually operating computer programs in the solar system, having been working since just prior to that launch.