1 / 12
great-red-spot
Starting 35 years ago, our view of the solar system was forever changed.
The launch of the Voyager 1 probe on Sept. 5, 1977 ushered in a golden era of planetary exploration. Along with its sister probe, Voyager 2, the spacecraft took the first detailed images of planets in the outer solar system, discovering magnificent rings, churning atmospheric processes, and volcanic activity on tiny moons. Voyager 2 actually launched on Aug. 20, slightly earlier than its counterpart, but took a longer route to reach Jupiter and Saturn after Voyager 1.
The Voyager probes were a scaled-back version of a proposed “Grand Planetary Tour” mission, which would have used a rare alignment in the outer solar system to swing from planet to planet with minimal fuel. In the original plan, four spacecraft would have visited all the gas giants and even tiny Pluto (then still a planet). But without budgetary support from President Nixon and Congress, the ambitious mission was canceled.
Since the 1977 planetary configuration occurred only once every 177 years, NASA engineers decided to go forward with a new plan — the Voyager probes, two identical robots that would travel to Jupiter and Saturn and, if successful, on to Uranus and Neptune. Voyager 1 ultimately performed a closer encounter with Saturn’s moon Titan that flung it out of the solar system, and only Voyager 2 made it to the latter planets.
We’re lucky that both probes made it as far as they did, since data from these missions was unparalleled until the more recent Galileo and Cassini probes. Both Voyager 1 and 2 are still operational, becoming some of the most distant man-made objects ever built (Voyager 1 is currently 11 billion miles from the sun) and have enough power to keep going until 2025.
Here we take a look at some of the best images and discoveries that these incredible probes produced during their flight through our solar system.
Above: