NASA has been quietly celebrating an important milestone in human achievement and exploration this year. It’s the 40th Anniversary of the launch of the Voyager spacecraft, and it’s worth taking a moment to salute these two endurable craft, even if you’re not a science groupie.
The birth of Voyager came about in 1965, when Caltech student Gary Flandro noticed that all four outer planets – Jupiter, Saturn, Uranus, and Neptune – would align on the same side of the sun in the 1980s. This rare event meant that travel time to these four distant members of our solar system could be cut by nearly two-thirds. How? By using the gravity of each planet to slingshot to the next planet.
But to take advantage of this alignment, the spacecraft would need to launch in the 1970’s. NASA was still riding high in the imaginations of the public and government officials at that time, and by 1972, the mission to explore Jupiter and Saturn was underway. (Uranus and Neptune would be added later when the spacecraft proved to be the little engines that could.)
The spacecraft launched in 1977, beginning a two year journey to the first stop of the grand tour, Jupiter. There would be a few glitches along the way, including the loss of the primary receiver on Voyager 1. But the results of the Voyager mission have been stunning. Voyager sent back images of active volcanos on Io and ice on the surface of Europa. The first close-up images of Saturn’s rings would prove the existence of shepherd moons. And as Voyager I passed beyond the bounds of our solar system, it would send back the image of the “family portrait”, the only images of Venus, Earth, Jupiter, Saturn, Uranus, and Neptune together. Earth appeared as a tiny speck, visible only because of the scattering of light. It was an image that would lead Carl Sagan to describe our home planet as a pale, blue dot.
Both Voyager craft are approaching the end of their careers. Voyager I passed through the heliosphere in 2014, officially leaving the solar system behind and crossing into interstellar space. VI is still sending back data, providing invaluable information on the extent of the heliosphere, as well as its importance. Readings from beyond the heliosphere’s edge show a place crowded with interstellar radiation that would be dangerous to life. V2, meanwhile is expected to cross the heliosphere in the next few years, expanding on the information we’ve already received.
The Voyager crew once occupied three floors at JPL. They now occupy a rented office, its two hundred plus team reduced to a handful. These are scientists and engineers so devoted to the mission that they have stayed with the spacecraft through the years. Some were there from day one, others joined later, in the 1980’s when the mission was extended.
The Voyager craft have been some of the most successful ever launched, and yet they are slowly (relatively speaking) moving towards the end of their life, as least from our perspective. Their signals will weaken, their systems will start to fail. They will continue to gather information and send data streams out into the universe. One day, perhaps, we will find a way to reconnect with these intrepid adventurers, but for now, the NASA team is waiting and watching, dreading the day when there is nothing but silence.
So if you happen to find a lovely bottle from the 1970’s, it might be time to crack it open. While our own supply didn’t include anything from 1977, we did find a 1979 Mouton Rothschild. The Voyager craft were halfway to Saturn by then, their full promise still only a gleam in the eyes of the Voyager team. It only seems fitting that something so amazing should be toasted with something equally wonderful. A wine that has achieved that careful balance, smooth and deep without being overly complicated. Just like Voyager.