• 2 months ago
A sonification of the Milky Way galaxy's core has been turned into sheet music. Find out how it was done.

Credit: NASA/CXC/A. Jubett
Transcript
00:00The Universe of Sound Data Sonification Project, it's all about taking NASA data, NASA images,
00:07and translating them into something that you can hear.
00:09This is done through mathematical mapping, where we're taking the pixels and just translating
00:14them into different kinds of sound bits.
00:18My name is Dr. Kimberly Arcand, and I'm a visualization scientist for NASA's Chandra
00:22X-ray Observatory at the Center for Astrophysics.
00:25I'm Sophie Kastner, and I'm a composer, and I wrote the piece, Where Parallel Lines Converge.
00:31My piece centers around the idea of spiraling.
00:34I'm always kind of looking for new things that we can try, new ways to understand things,
00:39new ways to process information.
00:41The initial plan was to take the original sonifications and translate them as accurately
00:46as possible into pieces to be played by musicians.
00:52When Sophie came into this project as a professional composer, she really brought a unique perspective.
00:59To me it just seemed like this brilliant idea of converting data to sound, not only for
01:04visually impaired people who then can appreciate these images that they can't necessarily see,
01:08but also as a supplemental tool for someone who's looking at the image who can then hear
01:12it.
01:13It was different once I started thinking about it from a composer's point of view.
01:17All of these objects seem so unknowable.
01:21So it's incredible to me that we have these opportunities to bring those objects down
01:25to Earth to help make them knowable.
01:28It is this idea of capturing light that's been traveling to us, translating scientific
01:32information into something we can perceive, something we can understand, something we
01:37can learn from.
01:39The title, Where Parallel Lines Converge, came from a poem that I read by Sarah Howe.
01:44It predicts black holes where parallel lines will meet, whose stark horizon, even starlight,
01:50can bend in its tracks, can't resist.
01:52It's been such a pleasure to work with Sophie as she works through this idea of translating
01:57a translation into something that can be played, paying attention to the NASA data, being authentic
02:03to the scientific story, but bringing it down into the sphere of human playable sounds.
02:11What she very smartly and adeptly did was focus on moments in the data that would make
02:16it a bit more bite-sized for an ensemble to play.
02:19The significant sections of the image where there's a real cool story to tell and a cool
02:24soundbed to make from that story.
02:35I was working with an ensemble of about seven musicians.
02:39I can't necessarily do this in the same way.
02:43Taking the data and incorporating computer software, okay, let me use the similar process
02:50to what the original sonifications did, but add my own spin to it because I also wanted
02:55to make it a piece of music suited to the instruments I was working with.
03:00To me, that's just a wonderful melding of science and art.
03:05The concept of using data and then translating it directly to sound was a really interesting
03:10idea to me.
03:12There's this huge emotional layer to looking at these images of space.
03:17Oh my God, I'm so small in comparison to this vast object.
03:23It's such a large feeling to have.
03:26I wanted to dig into those emotions.
03:32When you're talking about things like gamma-ray bursts, blazars, quasars, black holes, like
03:36all of these things sound too incredible to really understand, to have a personal connection
03:42to, but sound or music, you can.
03:46You can have a personal connection.
03:58The galactic center, this sort of inner 400 light-year region around Sagittarius A star,
04:03our very own supermassive black hole.
04:05It's this wonderful, dense, busy, active downtown region of the Milky Way.
04:11There's exploding stars, there are these x-ray binaries, there are these beautiful loops
04:16of material, all these massive stars.
04:19There's so much going on.
04:21The infrared data is mapped to a soft piano.
04:24The Hubble data is mapped to a plucky violin.
04:28And then the Chandra data is mapped to this sort of glockenspiel xylophone sound.
04:34Each of those sounds are very distinct.
04:35So as you scan, you sort of hear that soft, cooler gas and dust from Spitzer and that
04:41beautiful piano.
04:42But then Hubble's violin comes in and you can very clearly hear those very plucky moments
04:48of these gorgeous extended arches.
04:51And then as you get over toward Sagittarius A star, that monster of a black hole, you
04:56hear this little crescendo of high energy from Chandra.
05:01Humans and computers are different, obviously, and humans have limitations in terms of what
05:08they can play, what they can read.
05:12The music has to be legible to musicians.
05:17I didn't have the tools of like an entire orchestra of strings, you know, I have two
05:21string instruments.
05:22And I think the two string instruments I have, they can make so many different types of beautiful
05:28sounds that are more than just a pizzicato.
05:34Extra light would correspond with a very pure, high pitched tone.
05:42I kind of worked in that way where I categorized sounds that I had available to me, I corresponded
05:48them with parameters directly from the NASA data and directly from the original sonifications.
05:57I picked specifically the flute because it can play so high, but also because it has
06:02so many different textures and timbres that it can make.
06:10I decided to use the clarinet because I can also have that instrument doubling bass clarinet,
06:15which gives me this huge registral range.
06:23I really wanted to have percussion instruments because there are so many different kinds
06:27of sounds you can make with percussion instruments, especially the mallet instruments like the
06:31glockenspiel and the crotalus and the marimba, where, you know, it has a huge range, but
06:37it also has these really high, beautiful, like pingy, pure tones, and they're very celestial
06:45in sound.
06:46And the original sonifications also use a lot of glockenspiel, so I wanted to kind of
06:50harken back to that a little bit and use the glockenspiel and the crotalus, which have
06:54these really beautiful, pure tones to connote this celestial sound.
07:00You really hear this at the end of the piece, I have this whole section where it's zooming
07:05in towards the Sagittarius A star and you hear all of these repetitive, pingy, high
07:11textural sounds in the glockenspiel and the crotalus and the piano.
07:16And I really just wanted to convey this sense of vastness and also of just how many stars
07:23there are.
07:24They're all overlapping on each other and you can't even count them anymore.
07:34I don't think of these pixels, these photons in the same way anymore.
07:40I learned so much about space that I didn't know at all.
07:45What else can we do to make this processing of our data more interesting, more fun, more
07:50experiential?
07:51I'm all for new ways of knowing.