Nasa has shut down Voyager 1’s charged particles instrument to conserve power as the spacecraft continues its journey through interstellar space, now over 15 billion miles from Earth.
Nasa has taken the significant step of shutting down one of Voyager 1’s science instruments to conserve dwindling power. This decision comes as the nearly 49-year-old spacecraft continues its journey through interstellar space, now more than 15 billion miles from Earth.
Engineers at Nasa’s Jet Propulsion Laboratory (JPL) in Southern California sent commands on Friday to deactivate Voyager 1’s Low-Energy Charged Particles (LECP) experiment. This long-running instrument has been operational almost continuously since the spacecraft’s launch in 1977.
The shutdown is a response to the spacecraft’s ongoing power loss, which amounts to about 4 watts per year. Mission managers are focused on extending the remaining lifespan of Voyager 1 as it ages far beyond its original mission parameters.
“While shutting down a science instrument is not anybody’s preference, it is the best option available,” said Kareem Badaruddin, Voyager mission manager at JPL, in a statement. “Voyager 1 still has two remaining operating science instruments — one that listens to plasma waves and one that measures magnetic fields. They are still working great, sending back data from a region of space no other human-made craft has ever explored.”
The decision to shut down the LECP underscores the delicate balancing act facing the Voyager team as both Voyager 1 and its twin, Voyager 2, continue to age. Both spacecraft are powered by radioisotope thermoelectric generators, which convert heat from decaying plutonium into electricity. Over nearly five decades in space, engineers have had to progressively power down heaters and instruments to prevent critical systems from becoming too cold.
“The team remains focused on keeping both Voyagers going for as long as possible,” Badaruddin added.
The urgency of the situation increased after Voyager 1 experienced an unexpected drop in power during a routine roll maneuver on February 27. Engineers were concerned that any further decline could trigger the spacecraft’s undervoltage fault protection system, which is designed to automatically shut down components to safeguard the probe. Recovering from such a fault can be a lengthy process and poses additional risks, prompting the team to act before the spacecraft initiated a shutdown on its own.
The two Voyager probes remain the only spacecraft positioned far enough from Earth to collect data on detecting pressure fronts and regions of varying particle density in the space beyond our heliosphere, according to Nasa.
Engineers are optimistic that shutting down the LECP will provide Voyager 1 with about a year of additional operational capacity. Nasa’s press release stated that the team is using this time to finalize a more ambitious energy-saving initiative for both Voyagers, referred to as “the Big Bang.” This plan aims to further extend the operational life of the spacecraft.
The concept behind “the Big Bang” involves swapping out a group of powered devices simultaneously, hence the nickname. This would entail turning off certain systems and replacing them with lower-power alternatives, ensuring the spacecraft remains warm enough to continue gathering scientific data.
The decision to deactivate the LECP was not made hastily. Nasa indicated that mission science and engineering teams had previously agreed on the order in which spacecraft systems would be shut down as power availability diminished. Of the ten original instrument sets carried by the twin probes, seven have now been switched off. Voyager 2’s LECP instrument was deactivated in March 2025.
Given that Voyager 1 is now over 15 billion miles from Earth, commands take approximately 23 hours to reach the spacecraft. The shutdown sequence itself requires more than three hours to complete. However, one component of the LECP system — a small motor that rotates the sensor to scan in all directions — will remain powered, as it consumes only about half a watt. Engineers hope this will leave open the possibility of restarting the instrument in the future if additional power becomes available.
As the Voyager missions continue to push the boundaries of human exploration, the challenges of power management highlight the remarkable longevity and resilience of these pioneering spacecraft. The ongoing efforts to conserve energy and maintain operational capabilities reflect the dedication of the teams working to keep these missions alive.
According to NASA, the Voyager probes continue to provide invaluable data, contributing to our understanding of the universe.