NASA’s Quest to Upgrade the Voyager Probes From 16 Billion Miles Away
NASA’s Jet Propulsion Laboratory assembles Voyager 2 in March of 1977. It just got another upgrade, in 2026.
Credit: NASA/JPL
Earlier this month, NASA successfully completed an update to the Voyager 2 probe that researchers believe could extend its mission lifetime into the 2030s. Now, the same team is gearing up to perform a similar upgrade onboard Voyager 1, extending its lifetime as well.
How does a team upgrade a probe that’s already far beyond Pluto? Well, it comes down to the form of the upgrade.
The Voyager probes are both powered by devices that harness energy released during the decay of plutonium, which gives them a low maximum power output but also gives them incredibly long lifetimes. Nothing lasts forever, however, and even the Voyager generators produce about four watts less power every year.
Launched in 1977, the Voyager probes have endured this attrition for quite some time. Most estimates said that they wouldn’t be able to continue collecting data past 2028 or so.
An illustration of the trajectories of Voyager 1 and 2.
Credit: NASA/JPL
In the short term, the easiest solution has been to shut down nonessential scientific instruments to free up power, with each probe carrying 10 instruments at launch. Shutting down the planet-specific devices was a no-brainer, as the probes passed beyond the orbit of the furthest planets, but this did not stop the power supply from continuing to shrink.
Suddenly, the scientists had to do triage, deciding which valuable components to lose.
In other words, they were extending the probe’s lifetime at the expense of that lifetime’s usefulness. Now, we might want NASA to attempt to find newly efficient ways of doing things, to find ways of doing more with less. There are a number of difficulties with this, however, with one of the biggest being heat.
Put simply, the Voyager probes must create a certain amount and distribution of heat in order to remain functional. This led to certain components being left on partly for what they do, and partly for the heat they create.
The launch of Voyager 2, in August of 1977.
Credit: NASA
The Big Bang upgrade looked to address this. Though NASA hasn’t released specifics on which components got which changes, the team essentially devised a new set of components to turn off or leave on that would save about 10 watts of draw while still providing the heat output and distribution needed.
Those 10 watts equal 2-3 years of additional power decay before they’re back where they started.
The Voyager probes are now moving into the outer layers of the solar system, past certain thresholds that can make readings of interstellar space more fuzzy. Though extending the probes’ lifetimes by a few years might not seem like much, they cover an astonishing 300 million miles per year, meaning just a few more years of travel could provide significantly better readings.
As mentioned, these upgrades were all done to Voyager 2, but Voyager 1 can get the same treatment. NASA hopes to attempt that switch-over within the next few months.
