Air Date: Week of July 2, 2010

Astrophysicists predict that we will soon enter a period of unusually active solar flare activity. (Wikicommons)

Most of us think of the sun as the provider of light and warmth. But what about sound? Professor Robertus von Fáy-Siebenbürgen, the head of University of Sheffield's solar physics team, translates the magnetic vibrations for human ears and tells host Jeff Young how the sun is a star musical performer.

Transcript

YOUNG: Most of us look to the sun as our source of light and heat. But Robertus von Fáy-Siebenbürgen looks at the sun and hears music. He’s head of the solar physics team at the UK’s University of Sheffield, and has captured the magnetic vibrations of the sun’s corona and turned them into a sound. Listen:

[SOUND OF THE SUN]

YOUNG: So, professor, what are we hearing here?

VON FÁY-SIEBENBÜRGEN: This is awesome isn’t it? Yes I think the way to imagine this is that, imagine that you have a football and on the surface of the ball there would be little spikes. Now these little spikes, that are also on the sun, are made of magnetic field lines, you know magnetic field lines do not go into infinity like electric field lines, so they always are closed. They are like strings, like guitar strings, so it has a beginning and then an end. And, what you have here is the observation of these oscillations and the frequency is then transformed into the frequency of the human ear.

[SUN SOUNDS]

YOUNG: How does turning the data into sound help you better understand this?

VON FÁY-SIEBENBÜRGEN: Right. If you have a kidney stone, these days you’re not going to have an operation. What will happen, you go to the doctor, he’s using a sonic device, he launched a sound wave and your kidney reflects the sound wave, and there’s a smart device, which turns the reflected sound into an image, and the doctor can see in side your body. We can’t go into the sun or we can’t even go into the atmosphere of the sun, so what we do, we try to find in nature, a phenomenon which will generate oscillations or waves. We observe these reflected waves, we analyze these reflected waves, and then that’s the way we try to look into a star, or we try to look into the feature of the star.

YOUNG: So, when you’re hearing that, with your very practiced ear on this, what do you hear?

ROBERTUS: Noise.

[MUSIC]

ROBERTUS: No it’s not really noise it’s actually a beautiful music. Can I just give you another example? A very simple one that people can understand. You know when you go to the railway station, very often you see a gentleman having a hammer in his hand and he goes along the train and he hits the wheel of the train—

YOUNG: Kind of pinging them, yes.

ROBERTUS: Yeah. What he’s doing, we are doing exactly the same. This gentleman hits the wheel, and then he listens to the response of the wheel and if there’s a little crack he is able to identify with his ear, that the response, you know, the tone, the pitch, is different.

YOUNG: Right, it’s going to buzz a little and he knows something’s bad, yeah.

ROBERTUS: We do exactly the same. We know what frequencies they should have, and what we detect, what we hear, is different from what we would expect and then these differences are what is telling us information about the structure, or for instance, the internal structure of a star or the internal structure of one of those magnetic features in the atmosphere of the star. So this is the technique we are using.

YOUNG: You know, I’ve read that we are entering a period of very irregular activity with sunspots.

ROBERTUS: Absolutely correct.

YOUNG: Will that show up in the measurements that you’re taking here, will it change the tune that the corona is singing to you?

ROBERTUS: Yes, absolutely. So usually there is an 11-year cycle. Now what has happened, the last cycle there was a very long silent mode of the sun. There was very little activity, and what has happened this year, the activity has started to pick up and the prediction is that in 2012 or 2013 we may have one of the strongest activities that we have seen. And that bring us to another extremely interesting question. I would like to remind everyone that in 1859 there was a very strong solar activity, a solar eruption. Now if that solar eruption would have happened now, these days, that would have an absolutely serious consequence on life on earth because it would kick out our electric system.

YOUNG: Wow. What kinds of consequences can we expect from the upcoming activity then?

ROBERTUS: Well, very likely something will happen with strong activity. Now, what we should do, we should just observe the sun very carefully and try to predict these huge eruptions, and when the eruption happens we should try to shut down our electric system at least for a couple of hours so that the electric system is not damaged.

YOUNG: So going back to the fact that you’ve taken this data and put it in audible form, did it strike you that this has potential for music?

ROBERTUS: Uh, well you know. What is music? Music is very relative, isn’t it?

YOUNG; It’s in the ear of the beholder, I guess, yes.

ROBERTUS: Some people call music what Eminem plays, some people call music what ABBA plays (laughs), but, you know, I’m sure that if I show my grandmother Eminem she will say this is noise. (Laughs). So in a sense, what is music? It has a very wide range of interpretation. What we hear is music because there is some harmonies in it, if you like; there is some periodicity, but the truth, is that this is more or less like noise.

[SUN SOUND]

YOUNG: Robertus von Fáy-Siebenbürgen at University of Suffix England’s Solar Physics and Space Plasma Research Center. Thank you very much.

ROBERTUS: I thank you.

 

Links

Read more about the solar symphony from the University of Sheffield