As you read this, there are two hunks of metal, silicon, solder and yes, probably plastic the size of a Honda Civic hurtling through interstellar space at breakneck speed, having clocked 17 and 20 light hours since 1977. It sounds like a long drive across the North American continent until you realize that it takes only 8 minutes for light to reach the Earth once it breaks from the solar photosphere.
Besides our incessant radio broadcasts, NASA’s Voyagers I and II are the most distant manmade objects away from home. While Voyager I parted with the plane of the planets long ago after encountering Jupiter and Saturn, Voyager II survived its visits to all the giant planets before breaking out of the heliosphere in 2012. Suffice to say that we had no choice in the matter – when travelling through interstellar space, the voyage, above the destination, must be what counts. Consuming a mindbogglingly low amount of power (4W per year) and built to be tough, the Voyagers have defied expectations and remain functional. So, in addition to the scientific and symbolic importance, these two probes are now testing a new frontier: can the mission’s biological componentry keep up?
It’s Quieter in the Twilight is an endearing documentary about the small team of humans who still look after these two explorers – when they aren’t raising families, expanding their own horizons, feeding hobbies, and dealing with pandemics. Despite the space probes’ resiliency, they are still ancient machines made well-before the space shuttles, which, by the way, are retired. Working with Voyager sounds like trying to do Emergency Medicine with a geriatric patient with a 17 hr delay – you won’t even know if you’ve done something nasty until it’s too late. While it’s really out of necessity that they be brought into home lives, it is still touching when these machines become part of the family like a grandparent.
The Voyager program has always had a measure of luck, and it was fortuitous that a “stasis mode” was already planned when COVID-19 made everything pear-shaped. Despite the ravages of time, it is quite cosmic to hang one’s hat and anchor one’s life in a (slowly) moving dot between solar systems. Who can be confident that our work will still have relevance 50 yrs from now? The most ridiculous thing I learned was Voyagers’ command frequency changes by TEMPERATURE! In my mind the “report a robbery” Monty Python sketch is playing and each police constable has a speech register tuned to his body temperature…
Should the probes outlive their human caretakers, I hope there will be someone to pick up the baton so that one day some alien kid will be inspired by that weird space junk orbiting their home star. Just no interstellar war, please.