Voyaging blindly onward?

NASA’s Voyager 1 space probe, en route to its first destination, develops a potentially mission-jeopardizing problem: the scan platform, which contains and aims many of Voyager’s scientific instruments, jams and becomes stuck in place. As Voyager 1 has yet to even reach Jupiter, this threatens to make it an expensive failure. Transmitting commands from Earth to give the scan platform a gentle three-axis workout, engineers at NASA manage to free the stuck instruments, salvaging Voyager 1’s mission to the outer planets and their moons. (A similar fault develops in Voyager 2 during its 1981 encounter with Saturn.)