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 scientific instruments to conserve dwindling power, as the nearly 49-year-old spacecraft continues its remarkable 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 instrument has been operational almost continuously since the spacecraft’s launch in 1977.
The decision to turn off the LECP comes as the nuclear-powered probe loses approximately 4 watts of power each year. Mission managers are focused on extending the spacecraft’s operational lifespan as much as possible.
“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.”
This shutdown highlights the increasingly delicate balancing act facing the Voyager team as both Voyager 1 and its twin, Voyager 2, age far beyond their original mission plans. The two spacecraft are powered by radioisotope thermoelectric generators, which convert heat from decaying plutonium into electricity. After nearly five decades in space, engineers have had to gradually power down heaters and instruments while ensuring that the spacecraft do not become too cold, which could jeopardize key systems, including fuel lines.
“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, according to NASA. Engineers were concerned that any further decline could trigger the spacecraft’s undervoltage fault protection system, designed to automatically shut down components to protect the probe. Recovering from such a fault can be a lengthy process and carries additional risks, prompting the team to take action before the spacecraft did so autonomously.
The two Voyager probes remain the only spacecraft 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 confident that shutting down the LECP will give Voyager 1 about a year of breathing room,” a NASA press release stated. “They are using this time to finalize a more ambitious energy-saving fix for both Voyagers, which is referred to as ‘the Big Bang.’ This plan is designed to further extend the operational capabilities of the Voyagers.”
The concept behind “the Big Bang” involves swapping out a group of powered devices all at once—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 declined. Out of the 10 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 the door open for the possibility of restarting the instrument in the future if more power becomes available.
According to NASA, the ongoing efforts to manage power consumption and maintain operational capabilities highlight the dedication of the Voyager team to keep these historic spacecraft functioning for as long as possible.