In 18 months, it reached Jupiter and send home the first photos of this planet and its moons, Io and Callisto. The photos were so clean that they allowed researchers to see an erupting volcano on Io. On 12 November 1980, the probe flew well short of Saturn. In November 2003, Voyager 1 reached the boundaries of the Solar System. At a distance of 15 billion kilometers from the Sun, it is the most distant man-made object. The space probe carries the so-called Voyager golden plate, that is, a gold-plated visual disc containing the most important scientific data about Earth and humans, should the spacecraft ever be found by extraterrestrial civilizations.