Pioneer 10 was the first spacecraft to fly through the asteroid belt, first to fly close to Jupiter and first to cross Neptune's orbit on a course to leave our solar system.
In 1983, Pioneer 10 became the first spacecraft to travel past the orbit of the most distant planet, Neptune. Until its distance from Earth was exceeded on February 17, 1998 by Voyager 1, Pioneer 10 was the most distant human-made object.
It will take more than 2 million years for Pioneer 10 to pass Aldebaran, the nearest star on its trajectory.
It carries a plaque with information about Earth and humans.