Since the Nixon years, Voyager 2 has shed roughly 4 watts of usable power annually — and that slow bleed was on track to claim yet another one of its science instruments before 2026 ended.
Now it won’t. A procedure nicknamed the “Big Bang,” carried out by engineers at NASA’s Jet Propulsion Laboratory, should keep all three of the spacecraft’s still-active instruments alive for at least another year.
What the “Big Bang” actually did
No clever code or novel operating mode was involved. Working all at once, the team powered down certain components and substituted lower-energy alternatives, while keeping the spacecraft warm enough to go on functioning.
That final condition is the one most observers overlook. In deep space, heat isn’t waste you can dump — it’s a requirement of the system, and every watt reclaimed from one component is a watt that had been keeping something else above freezing.
The power supply has been shrinking the whole time
Radioisotope thermoelectric generators power Voyager 2 and its twin, Voyager 1. Plutonium decays, releasing heat; the generators convert that heat into electricity; and the plutonium keeps dwindling. Physics offers no refill, no upgrade path, no software patch.
Four watts a year reads as negligible. Stretch it across nearly fifty years and what’s left is a pair of spacecraft with virtually no margin.
The instruments have been going dark one by one
There are 10 instruments aboard each Voyager. A number of them were retired decades ago, having had work to do only during the mission’s planetary flybys.
What’s happened lately is a different story. Declining power has compelled the team to switch off two science instruments on each spacecraft since 2024 — not from hardware failure, but from a simple shortage of electricity.
Three working instruments remain on Voyager 2, and absent the “Big Bang” effort, that count was on course to drop to two before the end of 2026.
Voyager 1 is next
NASA plans to carry out the same power-saving swap on Voyager 1, which sits farther from Earth than Voyager 2 at present. The mission team anticipates wrapping up that work within the next few months.
By ordinary engineering standards, one additional year of data from a probe launched in 1977 is a modest payoff. It also happens to be the whole of what’s still available to a mission running on a decaying isotope — and the team went out and claimed it regardless.