On April 17, 2026, Scitechdaily 1’s Low-Energy Charged Particles experiment to conserve power, extending the probe’s mission. The move followed a critical power drop during a routine maneuver, forcing the team to prioritize survival over science. Both Voyagers, powered by decaying plutonium, now rely on meticulous energy rationing to stay operational.
After nearly half a century in space, NASA’s Voyager 1 and 2 probes face a slow, inevitable decline in power. Each spacecraft loses about 4 watts annually as their plutonium generators decay, leaving engineers to make painful choices: turn off instruments, risk system failure, or extend the mission by any means. On April 17, 2026, the team executed a calculated shutdown of Voyager 1’s Low-Energy Charged Particles (LECP) experiment, a move described as the best option available
by Voyager mission manager Kareem Badaruddin. The decision came after an unexpected power drop during a routine roll maneuver, which threatened to trigger the spacecraft’s undervoltage fault protection system.
A Delicate Balance of Power and Survival
Voyager 1 and 2, launched in 1977, were never designed to last 50 years. Their radioisotope thermoelectric generators (RTGs) convert heat from decaying plutonium into electricity, but this power dwindles by 4 watts yearly. By 2026, margins were razor-thin. While shutting down a science instrument is not anybody’s preference, it is the best option available,
Badaruddin said, per NASA’s April 17 report. The LECP, which had operated almost continuously since 1977, was next on a pre-planned shutdown list.
The shutdown was part of a broader strategy called “the Big Bang,” a coordinated effort to reduce power consumption by replacing high-energy systems with lower-power alternatives. Engineers on Voyager 2 had already tested this approach in 2025, freeing up enough energy to keep three instruments running for at least an additional year. The same method is now being prepared for Voyager 1, though its greater distance from Earth—over 15 billion miles—requires 23 hours for commands to reach it. This is the most important thing we’ve done on the Voyager spacecraft in decades,
Badaruddin told Scientific American, calling the test remarkably smooth.
The Human Element: Aging Tech and Vanishing Knowledge
The Voyagers run on 1970s-era assembly language, written for custom General Electric processors. Much of the original documentation has been lost, and the engineers who built the systems are retiring or gone. Larry Zottarelli, the last original Voyager engineer, retired in 2016. Today’s team relies on fragmented records and occasional help from retirees.
The power crisis also highlights the fragility of long-term space missions. Engineers must constantly balance turning off heaters and instruments with maintaining critical systems. The spacecraft power margins have grown razor thin,
NASA officials said in a statement, noting that the team must conserve energy by shutting off non-essential devices and systems.
This careful triage has allowed the Voyagers to outlast their original planetary mission, but the end looms.
What Comes Next for the Voyager Legacy
Despite the challenges, the Voyagers continue to send groundbreaking data from interstellar space. Voyager 1’s remaining instruments study plasma waves and magnetic fields in regions no other spacecraft has explored. The “Big Bang” strategy aims to stretch this window further, potentially reviving previously shut-down systems like the LECP if power allows. The team remains focused on keeping both Voyagers going for as long as possible,
Badaruddin said, per NASA’s April 2026 update.
For now, every watt saved is a victory. The Voyagers’ survival is a testament to both engineering ingenuity and the enduring human drive to explore. As they drift beyond the solar system, they carry not just scientific data, but a message: even in the vast, cold void, humanity’s reach extends far beyond its home. I don’t want to jinx it,
Badaruddin said of the Big Bang test, but this ‘big bang’ has gone remarkably smoothly.
