1In nineteen seventy-seven, two small spacecraft called Voyager left Earth on a journey that would last far longer than anyone imagined.
2Their original mission was simply to visit the giant planets Jupiter and Saturn, take detailed photographs, and then quietly come to an end.
3Instead, both of the probes kept on travelling, sending home precious information that changed our understanding of the outer planets forever.
4They revealed volcanoes on a moon of Jupiter and showed us the delicate, braided rings of Saturn in detail.
5Each spacecraft also carries a golden record filled with sounds, greetings, and music from every corner of human civilisation.
6This record is a message in a bottle, thrown into the cosmic ocean for whoever might find it.
7Voyager one has now finally crossed the invisible boundary where the sun's influence ends and true interstellar space begins.
8It is the single most distant object ever built by human hands, and it is still travelling tonight.
9In roughly forty thousand years from now, it will drift silently past another star, carrying our story into the darkness.
10Perhaps no one will ever find it, but the Voyagers remind us how far curiosity can carry a species.