The Voyager 1 spacecraft, launched in 1977 and currently located about 11 billion miles from Earth, has become the first man-made item to do what sounds like science fiction: it left the solar system.
Though it's taken a little more than a year to confirm, the unmanned NASA spacecraft traveled through a interstellar space full of charged particles from the galaxy, and crossed into a cooler, denser plasma on August 25, 2012.
The proof? It experienced a sudden drop in solar radiation and spike in cosmic particles.
Ed Stone was the Voyager's chief project scientist, and he puts Voyager's journey and its crossing of this threshold, into perspective.
Voyager's Golden Record
Voyager 1 and its sister craft Voyager 2 both carried what NASA called The Golden Record, a collection of Earth's sounds and sights for any "spacefarers" who might encounter the Voyager crafts on their journeys into space.
The contents included selections from the great masterworks of Western classical music — such as Bach's Well Tempered Clavier and Stravinsky's Rite Of Spring — the sound of thunder, volcanoes erupting, the sound of a mother and baby, the sound of a heartbeat, the sound of laughter, greetings in 55 different languages and music from different cultures — including Peruvian panpipes, Australian Aborigine songs and a Navajo night chant.
- What sounds and images would you have included on the Voyager? Tell us in the comments.
- Ed Stone, chief project scientist on the Voyager spacecraft.
This segment aired on September 13, 2013.