Zooming through the vast void of space at a speed of over 35,000 miles per hour, NASA’s Voyager 1 probe is now more than 15 billion miles from Earth. With the help of the Jet Propulsion Lab, NASA is determined to extend the probe’s operational life as long as possible. Recently, engineers at JPL successfully completed a critical power-saving experiment on Voyager 2, the twin of Voyager 1. This experiment involved toggling key components on and off in a precise and calculated sequence. The goal was to conserve energy while ensuring the spacecraft did not freeze in the extreme cold of deep space. The same strategy is now being prepared for Voyager 1.
Voyager 2's Power Strategy
Voyager 2, which is relatively closer to Earth, had the necessary power reserves to conduct this test. Due to the clever design of the spacecraft, nearly every instrument on board can generate waste heat, which helps keep the probe warm. This ingenuity, rooted in 1970s engineering, is something the Voyager team is eager to replicate with Voyager 1. Both probes rely on nuclear batteries known as thermoelectric generators. These generators harness the heat from the natural decay of plutonium-238 to produce electricity. However, as time passes, the amount of heat generated decreases, with each spacecraft losing about 4 watts of power per year.
The 'big bang' maneuver, as it is now called, involves switching off two of the heaters and an old tape recorder while activating two other heating units and a part of the propulsion system. This strategy saves nearly 10 watts of power annually, which is enough to keep the probe from suffering critical hardware failures due to freezing. This energy conservation is particularly crucial given the spacecraft's long journey into deep space, where temperatures are extreme and resources are limited.
Reviving a Key Instrument
The Voyager team is hoping to use the power savings from this fix to bring back an important instrument known as the Low-energy Charged Particles experiment. This tool is essential for measuring the density of interstellar particles. Unfortunately, the experiment had to be shut down earlier this year to prevent an unexpected system reset. Despite this, Voyager 1 still has two functioning science instruments—one that detects plasma waves and another that measures magnetic fields. These instruments continue to send valuable data from a region of space that no human-made object has yet explored.
Kareem Badaruddin, the mission manager for Voyager at JPL, described the recent test as the most important effort the team has undertaken in decades. Although he remains cautious, he noted that the test has progressed with remarkable success so far. If the same strategy can be applied to Voyager 1, the probe could remain operational well into the 2030s, given the right conditions. By this November, Voyager 1 is expected to reach a significant milestone—it will be one light-day from Earth. That distance, while a small fraction of a light-year, represents a staggering 173 times the distance between Earth and the Sun. From that point forward, it will take over 24 hours for messages sent to Voyager 1 to reach it, assuming the probe remains connected to Earth.
Mission Manager's Confidence
Suzanne Dodd, the project manager for Voyager at JPL, previously shared in a NASA livestream in 2022 that she believed Voyager 1 would definitely survive its 50th anniversary next year on September 5, 2027. Dodd also mentioned that if NASA experiences what she called 'really lucky' conditions, the probe might even remain active into the 2030s. This optimism is a testament to the team’s determination and the spacecraft’s resilience. As Voyager 1 ventures further into the unknown, the ingenuity of its designers and the efforts of the JPL team continue to ensure its longevity and the wealth of scientific data it provides.
