The Voyager I space probe, launched in 1977, conti...  ...which may be the final barrier before leaving the heliosphere and venturing into interstellar space. They don't...

Voyager I, the space probe launched 35 years a...  ...of Jupiter and Saturn, and may now have left the heliosphere -- tiny dot in the universe beholden to our sun....  ...ng Voyager, the kind that do not easily enter the heliosphere , to monitor its progress. Read more about it at t...