August 29, 2015

Bad Vibes - Let's talk about sonification of data

When I see news stories that talk about sound, sound waves, acoustics, or the physics of music my defenses usually go up as I'm reading through the article.  I try to suppress the urge to pick apart every little detail that isn't exactly right, but sometimes I can't help myself. 

One trigger for me is the sonification of data - in other words taking a time-varying signal and turning it into an audible sound. There is nothing wrong with using this technique to explore something in nature, but it does not mean that the object is emitting a sound wave, playing a tune, or singing.

I ran across this article last week from, which starts with the following:

In space, no one can hear you scream — that's because on Earth, sound waves move through the air, and there is no atmosphere in space. In empty space, there is no atmosphere, so the sound waves don't have a material to travel through. It's impossible for humans to hear sounds in the vacuum of space just like it's impossible to surf where there is no water — the waves need something to move through.

But last year, scientists recorded sounds coming from Comet 67P/C-G using the Rosetta Plasma Consortium (RPC) magnetometer instrument.
This instrument measured the sound wave vibrations in the comet's magnetic field, according to a statement from ESA....
When I followed the link to the statement from the European Space Agency, there was no use of the term "sound wave" anywhere in it. I guess the writer just wanted to spice up the story a little bit. There's nothing inherently wrong with writing a story to be accessible to a wide audience, but it just seems wrong to start an article with the fact that sound can't exist in the vacuum of space, but then in the next paragraph start talking about sound waves from a comet.

If you are a science writer, please remember: sonification of data does not necessarily mean something in nature is producing sound waves.


Andy Rundquist said...

I once invited someone to Global Physics Department who is blind and sonifies all her data. She made the point that she's able to see patterns that way quite easily. I forget her name and can't find my emails to her. I'll let you know if I can find them. I agree with you that there's a difference between sonifying something and saying it produces sound, of course.

Andrew said...

That's an example of a great use of sonified data - determining patterns, is a hugely important part of doing science. Thanks for sharing!