Sonification is a simple concept: translating information into sound. A synthesizer could be considered a form of sonification: taking a predetermined electrical frequency and mating it with a speaker to possibly pleasurable result--or at least interestingly unpleasurable. Just that is one of the best things ever, and by screwing around with those frequencies, usually adding or subtracting them, we can make just about any sound imaginable. Just by playing around with some numbers, you can make a violin, handclap, human voice, guitar, or really anything else.
We've figured out over a fairly recent history that most anything in the universe can be made audible as long as it has associated data/numbers. And, of course, anything you can think of does (brain waves, pulsars, whatever). A generated electrical frequency isn't quite the same thing as solar wind, but there's good reason one can be made into sound and the other can't. It's just a matter of translation. In doing so, we can hear the universe. Sometimes this adds to our appreciation, or gives us a way of experiencing something distant in the cosmos that otherwise we might just have to conceptualize through diagrams, or through the words of scientists.
For the rest of the story: http://motherboard.vice.com/read/spaced-out-making-music-with-the-sun