NASA Deactivates Voyager 1 Science Instrument to Extend Mission Life

On April 17, 2025, engineers at NASA's Jet Propulsion Laboratory sent commands to deactivate the Low-energy Charged Particles (LECP) instrument on the Voyager 1 spacecraft. The LECP had been operating for nearly 49 years since the probe's launch on September 5, 1977.

The action is intended to extend the operational life of the probe, which has been transmitting data from interstellar space for over a decade.

According to a NASA blog entry cited by one source, mission manager Kareem Badaruddin stated that while shutting down a science instrument is not the preferred option, it was the best available.

Power Management Strategy

The decision was made to conserve the spacecraft's diminishing power. Voyager 1 is powered by a radioisotope thermoelectric generator, whose power output decreases by approximately 4 watts each year.

In late February 2025, power levels fell unexpectedly during a routine maneuver, bringing the probe close to triggering an automatic fault-protection shutdown.

The deactivation follows a predetermined plan established years ago by the Voyager science and engineering teams. This plan outlines an order for deactivating spacecraft systems to balance power conservation with the continuation of unique scientific operations.

• The LECP on Voyager 1 was the next instrument scheduled for deactivation.
• Its twin instrument on the Voyager 2 spacecraft was deactivated in March 2025.
• Each Voyager spacecraft originally carried 10 identical instrument sets.
• Following this deactivation, seven of these sets have now been deactivated on each spacecraft.

Instrument Function and Mission Context

The LECP instrument measured low-energy charged particles, including ions, electrons, and cosmic rays. Its data provided information about the structure of the interstellar medium, such as pressure fronts and regions of varying particle density.

The Voyager spacecraft are the only operational probes positioned to collect this type of data from interstellar space, a region Voyager 1 entered in 2012 after crossing the heliopause. As of spring 2025, the spacecraft is more than 15 billion miles from Earth.

Current Status and Future Plans

Following the deactivation, Voyager 1 has two remaining operational science instruments: one for detecting plasma waves and one for measuring magnetic fields.

Engineers estimate the shutdown of the LECP could extend the mission's operational life by roughly one year.

A more comprehensive power conservation plan is being developed. This plan, informally referred to as "the Big Bang," involves a coordinated swap of several powered components for lower-power alternatives.

• Testing of this procedure on Voyager 2 is planned for May and June 2026.
• If successful, the same procedure could be attempted on Voyager 1 no sooner than July 2026.
• Project engineers hope to keep at least one instrument operating on each Voyager spacecraft into the 2030s.