When NASA launched their Voyager 2 space probe in 1977, they hoped to explore Sun’s outer planets. The spacecraft first observed Jupiter, Saturn, Uranus, and Neptune, before entering the uncharted waters of interstellar space. And all the while the Voyager 2 radioisotope batteries continued delivering sterling service. That said, even they are growing weaker now.
Saluting the Radioisotope Batteries on Voyager 2
A NASA technician accidentally transmitted the wrong command to Voyager 2 very early in August 2023. The signal should have been one in a series of many that realigned the antenna with the mother earth base-station. But alas, the command overstated the requirement and all radio contact was lost.
NASA could only hope that the Voyager 2 radioisotope batteries would continue functioning smoothly until the scheduled October 2023 auto-reset. Meanwhile their technicians continued ‘bombarding’ the space probe with messages according to BBC Science. One communication finally got through and the spacecraft is back on track again.
Radio isotope batteries (or thermo-nuclear generators) obtain their energy from active isotopes that have spare neutrons. This state allows them to deliver enough heat to generate sufficient power to enable the spacecraft’s operating system. Voyager 2 launched with 470 watts, but this has since fallen to 157 watts as the radioisotopes age.
The Technology Behind Voyager’s ‘Nuclear Batteries’
The Voyager 2 space probe launched with three ‘multi-hundred-watt’ radioisotope thermoelectric generators in 1977. Their collective power, as we described earlier has faded considerably. However, they still have sufficient energy to power five scientific instruments. But their life is growing short now.
The remarkable nuclear batteries have begun to draw on a reservoir of backup power intended for an onboard safety mechanism. The spacecraft will continue to signal its observations through to 2026. At this point, NASA expects the Voyager 2 radioisotope batteries will begin shutting down, although the probe will continue its journey through space for ever more.
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