9.08.2026

Voyager 2 would have had to shut down one of its last remaining instruments later this year, until NASA made some power changes.

NASA's Voyager 2 probe captured this image of Europa, the smallest of Jupiter's four Galilean moons, on July 9, 1979. (Image credit: NASA/JPL)

NASA just made an interstellar tweak to the Voyager 2 spacecraft, known as the "Big Bang", to keep its remaining 50-year-old science instruments running a little longer.

Voyager 2 and its twin launched in 1977, called Voyager 1, rely on a form of nuclear battery known as a radioisotope thermoelectric generator that uses the heat produced by the decay of plutonium. But the supply of plutonium on each probe drops at about four watts a year on each spacecraft.

To keep the probe running on this dwindling power supply, engineers recently reduced Voyager 2's power requirements by turning off a few non-science devices and using "lower-power alternatives" that are still effective enough to keep the spacecraft warm while it's so far from the sun, NASA officials said in a statement. "The spacecraft power margins have grown razor thin, requiring the team to conserve energy by shutting off non-essential devices and systems," NASA officials wrote of the mission, which is managed by the agency's Jet Propulsion Laboratory.

The drop in power is having a measurable science impact on both spacecraft — each has turned off two of their science instruments since 2024 alone. While some of these instruments were shut off after the spacecraft finished their historic planetary flybys decades ago, others were turned off due to power requirements.

Each spacecraft initially launched with 10 instruments, and Voyager 2 is now down to only three instruments. At first it looked as though Voyager 2 would have to shut down another of these instruments later this year, but luckily, the new power shifts will allow all three to operate "for at least another year," NASA said.

Voyager 1 will be tasked to do the same "Big Bang" power change "in the coming months." A signal to each spacecraft takes nearly 24 hours (or one light-day) to make a one-way journey, and officials noted Voyager 1 is further from Earth than its twin. (Voyager 2 is at about 142 astronomical units or sun-Earth distances, while Voyager 1 is nearing 171 AU.)

The two spacecraft initially launched to take advantage of a rare alignment between the outer solar system gas giant planets, which in order of distance from the sun are Jupiter, Saturn, Uranus and Neptune. Each Voyager spacecraft first flew past Jupiter and Saturn, taking unprecedented imagery of the planets and their moons.

Next, Voyager 1 was directed to fly above the plane of the solar system (also known as the ecliptic) while Voyager 2 continued flying past Uranus and Neptune, becoming the first spacecraft to see these worlds and their moons. Voyager 2's last planetary flyby was in 1989.

The two spacecraft continue to send scientific data from interstellar space; Voyager 1 passed into that region in 2012, while Voyager 2 did so in 2018. Voyager 1 is Earth's most distant spacecraft, currently around 15.9 billion miles (25.5 billion kilometers) away from us, according to NASA.

Quelle: SC

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NASA grants Voyager 2 probe another year of power with risky 'Big Bang' maneuver. Now, will it work for Voyager 1?

Voyager 1 is running low on power for science, but a successful energy-saving maneuver on Voyager 2 raises hope that the 50-year-old spacecraft can keep going.

Scientists are preparing for an interstellar rescue of humanity's most distant spacecraft, Voyager 1, after fixing up its twin from billions of miles away.

According to a NASA statement released Aug. 4, a clever power-saving maneuver known as the "Big Bang" helped the agency avoid having to shut off another one of the Voyager 2 probe's three remaining science instruments later this year. The Big Bang procedure involves selectively shutting off some high-power instruments on the Voyager probes while switching on lower-power alternatives, all while keeping the spacecraft warm enough to operate in the frigid environment of interstellar space.

"The idea is to swap out a group of powered devices all at once — hence the nickname — turning some things off, and replacing them with lower-power alternatives, to keep the spacecraft warm enough to continue gathering science data," representatives from NASA's Jet Propulsion Laboratory, which manages the mission, wrote in an April blog post.

NASA carefully ran tests on Voyager 2 before implementing the procedure in May and June. Now, sharing the results of those tests in the Aug. 4 statement, NASA reports a successful power transfer that should keep Voyager 2 running a while longer.

"The savings should provide power to keep its three instruments operating for at least an extra year," NASA wrote of the Big Bang.

But power is dwindling on both nuclear-powered spacecraft, and Voyager 1 is in worse shape than its twin. Mission scientists were forced to turn off one of Voyager 1's last remaining science instruments in April.

Voyager 1's turn for a life-extending Big Bang will happen within a few months, to keep science operating there as long as possible, agency officials added.

Going out with a bang

Scientists decided to do the "Big Bang" on Voyager 2 first because it is in better health, and closer to Earth, than Voyager 1. Voyager 1 is nearly 171 astronomical units (AU, where 1 AU is the average distance between Earth and the sun) from our planet, while Voyager 2 is about 143 AU away. Both spacecraft are crucial for revealing clues about the region outside the heliopause ‪—‬ the sphere of influence the sun exerts upon our solar system‪—‬ as they are the only working spacecraft at such a distance.

That distance is no small factor. In November, Voyager 1 will reach a milestone "light day" from Earth — when it takes 24 hours for a radio signal to travel one way from our planet to the spacecraft. Both spacecraft will also turn 50 years old in 2027, assuming they keep working.

Both Voyager probes launched in 1977, with Voyager 2 getting an opportunity for a "grand tour" of our solar system. An alignment of the outer planets — Jupiter, Saturn, Uranus and Neptune — that occurs only once every 176 years allowed both Voyager probes to maneuver from one planet to the next with minimal fuel usage.

Voyager 2 flew by all four planets, finishing its Neptune encounter in 1989, while Voyager 1 was tasked with flying above the plane, or "ecliptic," of our solar system after its closest approach to Saturn in 1981. As each spacecraft finished its close-up imaging of these planets, some instruments were shut off to extend their mission for as long as possible. But as the two spacecraft aged, more instruments needed to go quiet.

Plutonium, which the spacecraft rely on for power, has a natural decay rate, with the spacecraft now losing roughly 4 watts of power a year, according to NASA. In recent years, power supplies have turned critically low on both spacecraft. Voyager 2 would have needed to shut off one of its remaining three science instruments later this year if measures were not taken, and Voyager 1 was in slightly worse shape after an unexpected power drop in February occurred following a planned maneuver in deep space. Only two of Voyager 1's 10 science instruments remain powered after the latest was shut down in April.

Quelle: LIVESCIENCE