Voyager 1

Voyager 1, and its sister probe Voyager 2 were launched in January 1977 to take advantage of a rare alignment of the outer planets, that allowed a probe to get a gravitational assist, to boost their velocity, at each encounter. Voyager 1 flew by Planet Jupiter and Planet Saturn

As of 2026 Voyager is over 150 astronomical units from the center of the Solar system, and is the most distant man-made object.

The Voyagers are powered by the heat from nuclear decay, and the availablle power has dropped over the decades, and scientist have had to shut down most of their instruments. But they remains in contact with NASA. The Voyagers use tiny rocket thrusters to precisely point the probes' parabolic antennae at Earth. In 2004 Voyager 1's primary thrusters appeared to fail, so backup thrusters were put in use. In 2024 when the backup thrusters became clogged engineers turned on the primary thrusters heaters, and they turned out to be operational, after all.