Voyager leaving the solar system...

Voyager 1 is one of the most successful space missions of all time. Launched in 1977, it visited Jupiter and then Saturn, providing better close-ups of the two planets than had ever been seen before.

But it sailed on, crossing the orbits of both Uranus and Neptune (a sister craft, Voyager 2, actually flew by the two planets). Over all those years, there has been one constant in the Voyager flight: the solar wind blowing past it. This stream of subatomic particles leaves the Sun at hundreds of kilometers per second, much faster than Voyager. But now, after 33 years, that has changed: at 17 billion kilometers (10.6 billion miles) from the Sun, the spacecraft has reached the point where the solar wind has slowed to a stop. Literally, the wind is no longer at Voyager’s back.




Bad Astronomy: The Wind is no longer at Voyager's back