Voyager 1 Powers Down at 49 to Keep Exploring Deep Space

A 49-year-old spacecraft traveling 15 billion miles from Earth just made a sacrifice to keep exploring where no human-made object has ever been.

On April 17, NASA engineers powered down an instrument on Voyager 1 that had been studying cosmic rays and charged particles since 1977. The Low-energy Charged Particles experiment had worked almost continuously for nearly five decades, sending back unique data from beyond our solar system that no other spacecraft can collect.

The reason for the shutdown? Voyager 1 is running out of power.

The probe runs on a nuclear battery that converts heat from decaying plutonium into electricity. After nearly 50 years, it loses about 4 watts every year. Engineers now face a delicate balancing act: shut down systems to save energy while keeping the spacecraft warm enough that its fuel lines don't freeze.

The decision came after Voyager 1 experienced an unexpected power drop during a routine maneuver in February. The team acted quickly to prevent an automatic shutdown system from kicking in, which could have triggered a risky recovery process.

"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. Voyager 1 still has two working science instruments that continue sending back groundbreaking data from interstellar space.

The Bright Side

This isn't the end of the story. Engineers kept a small motor running inside the dormant instrument, using just half a watt of power. That means the experiment could potentially be restarted if enough power becomes available later.

The real breakthrough could come this summer. NASA is preparing an ambitious strategy nicknamed "the Big Bang" that would replace several power-hungry components with more efficient alternatives all at once. If it works, Voyager 1 could keep exploring for additional years beyond what seemed possible.

Engineers will first test the approach on Voyager 2 in May and June 2026, since it has slightly more available power and is closer to Earth. If successful, they'll apply the same fix to Voyager 1 no earlier than July.

The fact that we're still having this conversation about a spacecraft launched when disco ruled the airwaves speaks to extraordinary human ingenuity. Voyager 1 and Voyager 2 remain the only spacecraft far enough from Earth to study the boundary between our solar system and the rest of the galaxy.

Every extra day these spacecraft survive means new discoveries about a region of space we've never explored before. And thanks to creative problem-solving by NASA's team, humanity's farthest messengers aren't done talking yet.