Pasadena, CA – On April 17th, 2026, engineers at NASA’s Jet Propulsion Laboratory (JPL) in Southern California sent commands to shut down an instrument aboard Voyager 1 called the Low-energy Charged Particles experiment, or LECP. The nuclear-powered spacecraft is running low on power, and turning off the LECP is considered the best way to keep humanity’s first interstellar explorer going.
The LECP has been operating almost without interruption since Voyager 1 launched in 1977 — almost 49 years. It measures low-energy charged particles, including ions, electrons, and cosmic rays originating from our solar system and galaxy. It has provided critical data about the structure of the interstellar medium, detecting pressure fronts and regions of varying particle density in the space beyond our heliosphere. The twin Voyagers are the only spacecraft that are far enough from Earth to provide this information.
To conserve power, engineers at NASA’s Jet Propulsion Laboratory needed to turn off one of the science instruments on the most distant spacecraft ever built.
The choice of which instrument to turn off next wasn’t made in the heat of the moment. Years ago, the Voyager science and engineering teams sat down together and agreed on the order in which they would shut off parts of the spacecraft while ensuring the mission can continue to conduct its unique science. Of the 10 identical sets of instruments that each spacecraft carries, seven have been shut off so far. For Voyager 1, the LECP was next on that list. The team shut off the LECP on Voyager 2 in March 2025.
For more details, go to the Voyager blog on science.nasa.gov.
About NASA’s Voyager 1
NASA’s Voyager 1 is a historic space probe launched on September 5th, 1977, as part of NASA’s Voyager program to explore the outer planets of the solar system. After completing its primary mission of studying Jupiter and Saturn—and providing groundbreaking images and data of their moons and rings—Voyager 1 continued its journey beyond the planets. It is now the farthest human-made object from Earth and has entered interstellar space, the region beyond the Sun’s influence.
Despite its age, Voyager 1 continues to send back limited scientific data about conditions in interstellar space, powered by a radioisotope thermoelectric generator. The spacecraft carries the famous Golden Record, a time capsule containing sounds and images representing life and culture on Earth, intended for any potential extraterrestrial intelligence. Voyager 1 remains one of humanity’s most enduring achievements in space exploration.
