"Voyager 1" leaves solar system

[Viro]

Out of curiosity, what purpose do the magnetic measurements serve?

[Darkshadow]

They're reading the magnetic measurements of the sun, and how far out they went. They're saying that Voyager went out of the solar system because it just recently passed the point where the sun's magnetic influence passed away.

It's also measuring cosmic rays. Really, though, the main point of Voyager was to see how far the sun's magnetic influence went.