Voyager 2 trims systems to extend life

NASA engineers completed a power-saving overhaul on Voyager 2 on August 4 that is expected to keep the spacecraft’s three remaining science instruments operating into 2027, according to the Jet Propulsion Laboratory. The move comes as the probe’s radioisotope power source continues to weaken nearly 49 years after launch. NASA said the procedure involved shutting off some hardware and replacing other components with lower-power alternatives while keeping the spacecraft warm enough to function. Voyager 2 is one of two spacecraft still returning data from interstellar space. ### What exactly did engineers change on Voyager 2? NASA’s Jet Propulsion Laboratory said the team carried out a tightly choreographed procedure it calls the “Big Bang.” The work switched off heaters for Voyager 2’s thruster fuel lines and activated other devices that can keep the lines warm using less electricity, according to NASA’s August 4 mission update. (science.nasa.gov) The August 4 operation had to be done in a single step because Voyager 2 is so far from Earth that commands take many hours to arrive and telemetry takes many hours to return. The Register, citing NASA’s description of the maneuver, reported that several powered devices were turned off at once and lower-power replacements were brought online during the same sequence. (science.nasa.gov) ### Why is power suddenly so tight after all these years? Voyager 2 launched in 1977 with a radioisotope thermoelectric generator, or RTG, that converts heat from decaying plutonium into electricity. NASA has said the spacecraft lose about 4 watts of available power each year, forcing mission managers to shut down instruments and heaters in stages to keep core systems running. (theregister.com) In March 2024, NASA turned off Voyager 2’s low-energy charged particle instrument as part of that long-running power plan. At the time, the agency said the spacecraft would continue operating three science instruments and that its cosmic ray subsystem was expected to be the next instrument retired in 2026 if no other option emerged. (jpl.nasa.gov) ### Which instruments are still working now? Voyager 2 now continues to operate three science instruments in interstellar space, NASA said this week: the magnetometer, the plasma wave subsystem and the cosmic ray subsystem. Those instruments measure magnetic fields, plasma waves and energetic particles outside the Sun’s heliosphere. (nasa.gov) NASA said the new power strategy delays the need to shut down another instrument by about a year. The agency did not say the spacecraft’s power problem was solved; it said the change gives the mission more time before additional cutbacks are required. ### Where is Voyager 2 now, and why does it still matter? Voyager 2 crossed into interstellar space in November 2018, according to NASA mission material. (science.nasa.gov) The spacecraft is the only probe to have visited Uranus and Neptune, and it remains one of two operational Voyager probes still sending back data from beyond the heliosphere. NASA said the surviving instruments are still collecting measurements of the interstellar environment that cannot be made the same way from inside the solar system. (science.nasa.gov) The agency has described the Voyager mission as an effort to continue gathering data for as long as the spacecraft can generate enough electricity to operate. ### What happens next for the mission team? (ntrs.nasa.gov) NASA said Voyager 1 is expected to undergo a similar power-saving procedure later in 2026. The agency’s August 4 update said engineers will apply lessons from Voyager 2’s successful reconfiguration as they prepare the next round of commands for the twin spacecraft. JPL engineers have said the broader mission plan still involves staged shutdowns as power continues to decline. (science.nasa.gov) For now, NASA’s next named milestone is keeping Voyager 2’s current three instruments operating into 2027 while preparing Voyager 1 for its own lower-power swap.