The Sound Barrier #4: Listen to the universe

Summary

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Podcast Summary: Unexplainable

Episode: The Sound Barrier #4 – Listen to the Universe

Date: November 12, 2025 | Host: Noam Hassenfeld (Vox)
Featured Guests: Wanda Díaz-Merced, Bob (Robert) Wilson, Kim Arcand

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Episode Overview

This final installment in Unexplainable’s “The Sound Barrier” series explores how listening to the universe—rather than just looking at it—can dramatically expand our scientific understanding. The episode centers on the pioneering work of astronomer Wanda Díaz-Merced, who lost her sight but not her cosmic curiosity, and delves into “sonification,” the process of turning astronomical data into sound. Through rich storytelling and interviews, the episode digs into how sound has helped reveal the universe’s secrets, accessibility in science, and how different ways of sensing can revolutionize discovery.

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Key Discussion Points and Insights

Wanda Díaz-Merced’s Journey: Listening as Science

• Personal History & Inspiration

  • Wanda grew up in a small Puerto Rican town. Her childhood was marked by her sister’s illness and her own diabetes diagnosis, which led to eventual vision loss.
  • Despite hardships:

    “I cannot change, and then I’m blind and I have a disability, but also I’m the only one that can work in my family.” – Wanda (04:40)

  • Wanda almost abandoned her dream of space science—until a friend introduced her to listening to space using a homemade antenna. The “ugly” noise she heard turned beautiful and meaningful when she learned it was a live solar emission.

    “At that very moment, I was dying and that death sentence began to lift up... For the first time, I felt happiness in my life.” – Wanda (06:58)

• Learning to Listen

  • Wanda discovered scientists had been listening to space for decades by shifting non-audible waves (like radio waves) into the range of human hearing.
  • Struggled academically due to lack of accessible reading tech, but persisted by learning from others in libraries.

The Role of Sound in Major Discoveries

• Bob Wilson and the Accidental Discovery of the Big Bang

  • Nobel Laureate Bob Wilson and his partner detected “static” in their radio antenna, which turned out to be the cosmic microwave background—the afterglow of the Big Bang.
  • The process involved ruling out earthly noise (including pigeon droppings!).

    “There was a pair of pigeons that lived in the antenna… So we put a little bait in there, caught the pigeons, but none of that made any difference.” – Bob (13:23)

  • Eventually, this faint sound was recognized as pivotal evidence for the Big Bang theory.
  • When realization finally hit:

    “We weren’t quite ready to say that that’s the only possibility.” – Bob (15:32)

• Sound in the Astronomer’s Toolkit

  • Sonification—translating any kind of astronomical data (imaging, X-rays, light curves) into sound—helps scientists perceive patterns and properties otherwise missed.
  • Wanda’s pioneering work in sonification at NASA, including detecting subtle signals (like neutron star mergers and gamma-ray bursts), led to new findings.

    “Audio will increase perception to things that are blind to the human eye.” – Wanda (22:16)

How Sonification Expands Science

• Accessibility & New Discoveries

  • Wanda’s tests showed astronomers using both sound and images did better at pattern recognition than either alone.
  • She used sonification to spot undiscovered resonances in gamma-ray burst data.

    “These resonances had not been identified by anyone. They had not been discovered before.” – Wanda (25:56)

• Kim Arcand and Multisensory Astronomy

  • Kim Arkand (NASA Chandra Observatory visualization scientist) described transforming X-ray data into soundscapes for images like the Pillars of Creation and the galactic center.
    • Example: Piano (infrared), plucky violin (Hubble), glockenspiel (Chandra X-rays) represented different energy ranges.

      “So you could hopefully hear that little crescendo at the end that is our supermassive black hole. So it’s really singing in X-ray light.” – Kim (30:08)

  • The act of listening to these data, rather than instantly seeing everything at once, fosters deeper, more deliberate analysis.

    “It changed how I thought of this data set… I never noticed. This is so strong there. How did I not notice that?” – Kim (30:53)

Rethinking Science: Beyond Vision

• Challenging Visual Dominance

  • Both Kim and Noam reflect on the bias that “seeing is believing,” reminding listeners that most astronomical discoveries are rooted in data invisible to human sight.
  • Even famous astro-images are color-mapped composites, not literal visual data.

• No Representation is Fully “Real”

  • The show argues convincingly—citing neuroscientist Dan Polley—that all perception is a construction of the brain and each sensory translation is equally valid in probing reality.

• Inclusion and Expansion

  • Sonification opens astronomy to those traditionally left out—especially people who are blind or low-vision.

    “Sonification of these types of objects has shown me that, like I might be welcomed working for NASA, working at an observatory.” – Kim (34:30)

  • Wanda cites feedback from her students:

    “I never thought I would be able to... It was by listening to the data that I realized that I can continue forward.” – Wanda (34:49)

The Future: Science Without Limits

• Institutes and Ambitions
  • Wanda is launching an Institute for Multi Sensory Science. Scientists aim to sonify 20,000 galaxies and probe for dark matter using sound.

    “If we bring more skills to science, we will have to delete the word limit. The emergence of science would be incredible.” – Wanda (36:43)

  • Accessibility is not just a moral issue but also a source of scientific enrichment.

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Memorable Quotes & Moments (with Timestamps)

• The Transformative Power of Listening:
  • “At that very moment, I was dying and that death sentence began to lift up. You have no idea. For the first time, I felt happiness in my life.”
    — Wanda Díaz-Merced (06:58)
• Science as a Process of Elimination:
  • “There was a pair of pigeons that lived in the antenna… So we put a little bait in there, caught the pigeons, but none of that made any difference.”
    — Bob Wilson (13:23)
  • “There was poop in the antenna.”
    — Noam Hassenfeld (13:54)
• The Value of Diverse Methods:
  • “Listening to data like this… it forces you to slow down.”
    — Kim Arkand (31:17)
• Dismantling Limits:
  • “If we bring more skills to science, we will have to delete the word limit. The emergence of science would be incredible.”
    — Wanda Díaz-Merced (36:43)

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Important Segment Timestamps

• Wanda’s Early Life and First Encounter with the Sun’s Sound: 01:53 – 07:41
• How Sound Travels (Physics of Sound and Space): 09:03 – 10:24
• History: The Accidental Discovery of the Big Bang (with Bob Wilson): 11:09 – 17:33
• Introduction to Sonification at NASA: 21:06 – 23:15
• Black Hole, Neutron Star, and Gamma Ray Burst Sonifications: 23:15 – 26:18
• Building Blocks of Life and Wanda’s Contributions: 26:18 – 27:14
• Kim Arkand on Visualizations & Sonification at Chandra: 27:14 – 32:35
• Broader Implications & Inclusion in Science: 32:35 – 36:43
• Wanda on the Future and Removing Limits: 36:43 – 37:24

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Conclusion

This episode powerfully argues the case for rethinking how we perceive and study the universe. Through the stories of trailblazers like Wanda Díaz-Merced and scientists like Bob Wilson and Kim Arkand, listeners are invited to imagine a universe not limited by human senses—where listening becomes as vital as seeing, and where broadening participation in science leads to richer discoveries. The episode concludes with a call to dismantle barriers: in access, in imagination, and in the very senses we use to explore reality.

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Transcript

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Support for the show comes from the Audible original the Downloaded Ghosts in the Machine Earth's final days are near and the clock is ticking for members of the Phoenix colony. All they need to do is upload their minds back into the quantum computer. Simple enough. But their plan is disrupted by digital duplicates of their own minds that could destroy their stored consciousness forever. Listen to Oscar winner Brendan Fraser reprise his role as Roscoe Kadoulian in this follow up to the Audible hit sci fi thriller the Downloaded by Canada's most decorated sci fi author, Robert J. Sawyer. What are you willing to lose to save the ones you love? Find out in the thought provoking sequel the downloaded Two Ghosts in the Machine, available now only from Audible. Hello, can you hear me? Wanda Diasmerced can make pretty much anything seem special.

[Wanda Diasmerced]

Can you say 1, 2, 3?

[Noam Hassenfeld]

Like when I first called her up and we were working through some connection issues. One, two, three.

[Wanda Diasmerced]

Oh, this is very good. You say one, two, three beautifully.

[Noam Hassenfeld]

Oh, thanks so much. Or the way she talks about Star Trek.

[Wanda Diasmerced]

It's awesome, right? It's the best thing that has ever happened.

[Noam Hassenfeld]

See, she really loves Star Trek.

[Wanda Diasmerced]

You cannot miss that.

[Noam Hassenfeld]

And Wanda's always been like this, ever since she was a kid.

[Wanda Diasmerced]

I do remember that my sister was bed bound for a very long time. And at that time, the movable bed that she had, it had some steel tubes on the side and she had a cast that would go from below her neck to covering the two legs. So to me she was an astronaut in a spacecraft and we would play many, many, many times. Like being astronauts.

[Noam Hassenfeld]

Wanda didn't have an easy childhood. She grew up in Gurabo, this small city just outside of Caguas in Puerto Rico. Her family didn't have a lot of money or education. Her sister was chronically ill. Wanda was diagnosed with diabetes when she was just 10. And even though she'd played astronaut, she never considered studying space. Until one day she was out fishing with her dad and she looked up.

[Wanda Diasmerced]

I remember clearly, three beams of a meteor. One was reddish, the other ones were more towards the bluish side. And I remember that it lasted like less than a second. And I made this expression like, you know, like to me that Was like, it has been like the greatest thing. And my father, he turned toward me and he said, those are rocks falling from the sky. And what he was telling me is, that's not a spiritual thing. There is science behind it. Those are rocks falling from the sky. So at that moment, it's like, I need to learn more about those rocks. Where are they coming from?

[Noam Hassenfeld]

Wanda eventually went to college to study science. But by this point, her diabetes had gotten worse and she was starting to lose her vision.

[Wanda Diasmerced]

Noam, there is a problem and is that if you cannot read, your grades will be very, very, very bad, right? And if you have no one reading to you, your grades will be worse. So I would intuitively guess answers.

[Noam Hassenfeld]

She thought about trying to study something else.

[Wanda Diasmerced]

But I didn't have the minimum GPA to transfer to another faculty, so I had to stay in science and thinking, what am I going to do in the field of I cannot see.

[Noam Hassenfeld]

And.

[Wanda Diasmerced]

I cannot change, and then I'm blind and I have a disability, but also I'm the only one that can work in my family.

[Noam Hassenfeld]

Her father had lost his job. Her sister was still sick. It was a lot of pressure for a 22 year old.

[Wanda Diasmerced]

I cannot leave the university because it's going to be a major family situation.

[Noam Hassenfeld]

Wanda hadn't really come to terms with the fact that she was going blind. She kept hoping that one day she'd just wake up and suddenly be able to see again. So she didn't really talk about it. And she only had one friend who noticed.

[Wanda Diasmerced]

He was the only one who knew something was happening to me because I would sit and would not move unless I would perceive that no one else was in the hallway.

[Noam Hassenfeld]

Her friend Emilio happened to be the president of the Astronomy Club. And when he saw how much Wanda was struggling, he had an idea.

[Wanda Diasmerced]

He said, juanita, I want you to come with me and I want you to listen to what I have in my house.

[Noam Hassenfeld]

Emilio showed her this small antenna he had in the back of his house, basically just two hanging metal wires. He handed her a pair of headphones and she listened.

[Wanda Diasmerced]

It was white noise, right? And then increases, right? And then. And then it diminishes. It may have lasted about 30 seconds. And I said, emilio, turn that off. It's horrible.

[Noam Hassenfeld]

But Emilio didn't turn it off. He kept playing it. This is a recording of the actual sound they were listening to, by the way. And finally he told her what it was.

[Wanda Diasmerced]

He said, wanda, I think that is a sunburst. It was a real time detection of a solar emission.

[Noam Hassenfeld]

Wanda was literally hearing the sun. And as luck would have it, she was tuning into one of the most powerful solar storms ever recorded. She was hearing the sun's outer atmosphere being blown off into space.

[Wanda Diasmerced]

And at that moment, everything transformed from me perceiving that those sounds were bothersome and ugly, it transformed into beauty even more, the sense of possibility. Right? My world was closing up bit by bit. Honestly speaking, at that very moment, I was dying and that death sentence began to lift up. You have no idea. For the first time, I felt happiness in my life.

[Noam Hassenfeld]

It was like she was a kid again, coming face to face with the sky. And she realized she wouldn't have to give up on her dream. She could still study space. She'd just have to listen to it instead.

[Wanda Diasmerced]

When you listen to it, it's not a cold, not moving space. It's very, very active. It's full of dynamism. It's full of. It's full of life.

[Noam Hassenfeld]

I'm Noam Hassenfeld, and this is the final episode of the Sound Barrier, a series from Unexplainable about the limits of our senses and the ways we can break through. On today's episode, what are we missing when we just look out into space? And what can we learn from if we listen? If you've only ever heard one thing about space and sound, it might be from the movie Alien. There's gotta be a way of killing it.

[Bob Wilson]

How?

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[Noam Hassenfeld]

It was on the poster, it was in the trailers. You can't. In space, no one can hear you scream. It's a pretty great tagline, but it's also scientifically accurate.

[Wanda Diasmerced]

Sound as we know it here on Earth, it needs air. It needs a means of propagation to be detected by an Earth sound is a pressure wave.

[Noam Hassenfeld]

It's basically just a vibration, which means it needs something to move through. It could be air, it could be water, it could be the ground. So when someone is talking to you in a room, they're literally making the air vibrate, which makes your eardrum vibrate, which your brain hears as sound. But space is almost a complete vacuum, which is why it's pretty much silent. But there are other kinds of waves that can move through space. Visible light, X rays, gamma rays. And some of them, like radio waves and microwaves, can be picked up by antennas and shifted down into our hearing range.

[Wanda Diasmerced]

You have an electronic device in the receiver that brings it into the frequency of human hearing.

[Noam Hassenfeld]

That's what Wanda was hearing in her friend's backyard. Radio waves shooting out from the sun picked up by the antenna shifted down so she could listen. Wanda was so blown away by what she heard out there that she wanted to learn everything she could about listening to space. But she still had to deal with all the limitations of her life on Earth.

[Wanda Diasmerced]

Remember, I couldn't read the books. Screen readers were not available. So I was asking people sitting in the library, can you find on the computer this or that or whatsoever? And whatever search engine that was available would bring this information to us.

[Noam Hassenfeld]

But you learned that scientists had been listening to space for decades. Like the engineer who was able to listen to the center of the Milky Way, or the physicist who listened to plasma waves, these ripples through charged particles in space. Or the scientist who used sound to help him make one of the biggest scientific discoveries of the 20th century.

[Bob Wilson]

I didn't realize at the time how big it was, but I do now.

[Noam Hassenfeld]

That's Robert Wilson, usually known as Bob.

[Wanda Diasmerced]

You spoke to him.

[Noam Hassenfeld]

Wanda was pretty pumped. Bob is extremely chill about the whole thing.

[Bob Wilson]

We weren't even so impressed with cosmology.

[Noam Hassenfeld]

Bob's almost 90 now, and he hasn't stopped. He's a senior scientist at the Harvard Smithsonian center for Astrophysics. And he's one of the first names Wanda came across when she was diving into the history of listening to space. Because Bob and his partner used sound to help them find the first direct evidence of. Of the Big Bang. And it happened by accident. Back in the 60s, Bob was pretty different. Well, I had hair, still just as understated. And he was a young physicist working with his partner on a new antenna, trying to measure microwaves from outside the Milky Way. But when they went to make their first measurement, they noticed this problem.

[Bob Wilson]

There was this booming signal. The antenna was twice as hot as it was supposed to be.

[Noam Hassenfeld]

When Bob put on his headphones, it sounded like some kind of static.

[Bob Wilson]

If you had a television and you turned to an off channel, you would get a hiss.

[Noam Hassenfeld]

Yeah, like the snow.

[Bob Wilson]

Yeah, same effect. We were very disappointed at that point and started thinking about what could be wrong.

[Noam Hassenfeld]

They kept listening to the sound to make sure it wasn't just noise from somewhere nearby like the city. But no matter which direction they pointed the antenna, they still heard the hiss.

[Bob Wilson]

So that couldn't be it.

[Noam Hassenfeld]

They thought it might be radiation from a nuclear weapons test. So they waited a few months, measured again, still had that hiss.

[Bob Wilson]

Nothing had changed.

[Noam Hassenfeld]

They even thought it might be something. Let's just say closer to home.

[Bob Wilson]

There was a pair of pigeons that lived in the antenna.

[Noam Hassenfeld]

There were pigeons that lived in the antenna?

[Bob Wilson]

Yes.

[Noam Hassenfeld]

Okay.

[Bob Wilson]

We'd see them flying in and out. So we put a little bait in there, caught the pigeons, but none of that made any difference.

[Noam Hassenfeld]

So even after the pigeons were gone, you still heard the hiss.

[Bob Wilson]

Right?

[Noam Hassenfeld]

Bob still wasn't anywhere close to thinking about the Big Bang. He was still thinking about those freaking pigeons.

[Bob Wilson]

They had deposited pigeon dropping inside the antenna.

[Noam Hassenfeld]

There was poop in the antenna.

[Bob Wilson]

Well, they'd been living in there. What do you expect? Okay, we just scrubbed it out. It wasn't a big deal.

[Noam Hassenfeld]

Bob didn't really spend too much time pondering the origins of the universe. He figured it had just always been there.

[Bob Wilson]

The idea that it's the same now as it was before and will be the same in the future, that's what.

[Noam Hassenfeld]

Most people thought at that point. But there was this other idea that was starting to gain some traction. The Big Bang. That the universe started in this gigantic explosion. But Big Bang believers were still looking for their smoking gun.

[Bob Wilson]

The expectation was if the universe started out very hot and full of radiation, it would still be full of radiation. There would be something left over from the initial explosion which one could detect.

[Noam Hassenfeld]

Bob started telling other scientists about the hiss. And when the Big Bang brigade finally heard about it, they were like, Bob, you found it. That hiss, which is all over the place all the time and is definitely not pigeons, that's the leftover radiation from the Big Bang. When you found out that what you had been noticing for nine months could, I don't even know how to say this, like, could be the answer to the origin of the universe, what did you feel?

[Bob Wilson]

I think we felt that, yes, that's a possibility. Maybe there's some other explanation.

[Noam Hassenfeld]

You just weren't that, you weren't that.

[Bob Wilson]

Excited, not terribly excited. We weren't quite ready to say that that's the only possibility.

[Noam Hassenfeld]

About a year later, after a bunch of follow up research, Bob got a call from a reporter at the New York Times and finally he started to buy into the hype.

[Bob Wilson]

The next morning, my father walked down to the local pharmacy and bought a New York Times. And there on the front page of the New York Times was a picture of the antenna and an article about this discovery.

[Noam Hassenfeld]

Written on top of that picture was the headline, Signals Imply a Big Bang Universe. By the time Wanda was learning about Bob's story, the Big Bang had become something astronomers and really lots of people just took for granted. Of course the universe had a beginning. Of course it was this really big explosion. But every fact that seems like bedrock truth once had a Beginning where it shifted from a wacky idea to something we all just accept. And for the Big Bang, that moment was when Bob and his partner noticed this signal. This is the actual sound they heard when they put on their headphones. A lot of it's just static from the instruments, but a good amount of it, like 10%, is the leftover radiation from the Big Bang. It's the sound of the creation of the universe. Bob and his partner eventually won a Nobel prize for their work, and they created a precedent for Wanda to follow. That sound can play an essential role in some of the biggest scientific discoveries in history. So you can see why Wanda would kind of freak out when I brought up Bob.

[Wanda Diasmerced]

Noam, I'm so moved that you spoke to Wilson. Well done.

[Noam Hassenfeld]

But Bob was only listening to a small slice of the universe, microwaves that were shifted into our hearing range. In a minute, Wanda learns how to listen to everything else. Support for unexplainable comes from Quince. All right. You wake up in the morning, it's chilly. You don't want to plan an outfit. You want stuff that's easy, that's nice, that looks good. And you want stuff that's warm, especially warm. And that is Quint's. This season. They've got $50 Mongolian cashmere sweaters that feel like an everyday luxury. They've got wool coats that are stylish and durable denim that nails the fit and the construction. And they're all at a fraction of what you might expect to pay. That's because Quint's partners directly with factories and top artisans, cutting out the middlemen. And the bonus. Quince makes great gifts, too. I've gotten to try a couple things from Quince, and I really do love the cashmere sweater. It's soft, it's warm, looks great. Don't even think twice about what to wear on that chilly fall morning because it's warm. Step into the holiday season with layers made to feel good, look polished, and last. From Quince. Perfect for gifting or keeping for yourself. Go to quince.com unexplainable for free shipping on your order and 365 day returns. Now available in Canada, too. That's Q-U-I-N-C-E.com unexplainable to get free shipping and 365 day returns. Quince.com unexplainable oh, hey. Welcome to gift wrapping.

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[Wanda Diasmerced]

Wow.

[Noam Hassenfeld]

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[Noam Hassenfeld]

I'm the worst. I only got my mom a robe.

[T-Mobile Customer]

Well, it's better than socks.

[Noam Hassenfeld]

So I have to trade in my old phone, right?

[T-Mobile Customer]

No AT T Mobile. There's no trade ins needed when you switch. Keep your old phone or give it as a gift.

[Noam Hassenfeld]

Incredible.

[T-Mobile Customer]

In fact, wrap up my old phone too for my aunt Rosa.

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[Noam Hassenfeld]

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Oh, I got it. I'll give it to my abuela. I'll take reindeer paper with.

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[Bob Wilson]

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[Noam Hassenfeld]

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[Wanda Diasmerced]

You'll find that every heavenly body has.

[Noam Hassenfeld]

Its own particular scent. A few years after Wanda started learning about listening to space, she found herself at NASA. She couldn't believe how she pulled it off, but she got an internship that.

[Wanda Diasmerced]

Was a huge blessing because my grades were very, very, very, very, very, very very.

[Noam Hassenfeld]

And she wasn't just planning to listen to that tiny slice of the universe. The radio waves, the microwaves. She wanted to hear the meteors she saw as a kid. So she started working on something called sonification.

[Wanda Diasmerced]

Sonification is bringing information into the audible domain in order to augment your perception.

[Noam Hassenfeld]

Sonification isn't what Wanda was doing when she heard that sunburst in her friend's backyard, or what Bob was doing when he heard that hiss left over from the Big Bang. They were directly listening to things like radio waves or microwaves that were shifted into the range of human hearing. But sonification is a Way to translate any kind of data into sound. You can take things we can see, like stars or galaxies, Things we can't see, Like x rays or infrared light, and you can translate them into something we can hear. It's kind of like a Geiger counterthose little handheld gadgets that tell you about radiation levels by playing a bunch of clicks. Those clicks aren't what radiation sounds like. They're just a translation of the data. They're a way for scientists to hear where the radiation is and how strong it is.

[Wanda Diasmerced]

Audio will increase perception to things that are blind to the human eye.

[Noam Hassenfeld]

Sonifications don't need to sound like the big bang, Background fuzz or whooshing sunbursts. They can sound like anything as long as they're clearly communicating the data. And it's often a lot easier to hear things Than it is to see them. This is a sonification Of a mouse walking. I love this example. Every sound you're hearing Is a pair of paws hitting the ground. And now here's a mouse that has a genetic mutation which makes it wobble when it walks. If you wanted to find out exactly when its paws hit the ground, it would be pretty hard to tell Just by looking at it. But it's obvious when you listen. So Wanda was curious if she could harness this potential for astronomers. And she set up a test.

[Wanda Diasmerced]

I simulated a task that astronomers used for the detection of black holes.

[Noam Hassenfeld]

She gave scientists simulated data that looked like what happens when gas swirls around a black hole. There were graphs that showed where the radiation was strongest, and there were sounds that showed the same thing. Some examples were clear. Other ones were trickier. And when astronomers used both the graphs and the sounds, they did better Than when they just used one or the other. But audio was just about as good As a graph on its own, Sometimes even better. Which gave Wanda confidence that she could make new discoveries by listening to different parts of space. Like the merger of two neutron stars, These ultra dense remnants of exploded supernovas. Each hit you're listening to Is a measurement of the energy given off by these two stars as they're orbiting each other. Louder hits, more energy. Softer hits, less energy. And Wanda chose to use these high pitched timpani hits for this sonification so she could hear the tempo changes really clearly.

[Wanda Diasmerced]

If you hear the changes, the ups and downs are quite uniform. But then at the end, There is an area where it seems the tempo is changing. It feels a little bit faster.

[Noam Hassenfeld]

Right there. There's a little hiccup in the tempo.

[Wanda Diasmerced]

And it's telling me about how the system is rotating. It's not as uniform as we think.

[Noam Hassenfeld]

She's even used sonification to find things no one had noticed before. Like in a gamma ray burst, this huge explosion that happens when a star dies.

[Wanda Diasmerced]

The interior of the star collapses under its own weight and it starts rotating ever faster, like an ice skater. When pulling their arms in close to their body.

[Noam Hassenfeld]

Wanda actually gave a TED talk about this gamma ray burst. She decided to zoom into a part of it that other people might have missed. This part that might have just been confused for noise in the data.

[Wanda Diasmerced]

And I want you to hear what I heard. You will hear it as a very fast decrease in volume is frogs at home. Don't pay attention to that.

[Noam Hassenfeld]

That's the fast decrease in volume she's talking about right there. It's really subtle. It's also kind of masked by a frog. But there's a moment where it gets softer. Here it is again. Wanda says she's the first person to.

[Wanda Diasmerced]

These resonances had not been identified by anyone. They had not been discovered before.

[Noam Hassenfeld]

It's still kind of mysterious. And Wanda says there needs to be more research. But she thinks that tiny decrease in volume might offer new ways to understand these dying stars and the way they give birth to matter.

[Wanda Diasmerced]

The elements that form the molecules that form the chemical building blocks of life are produced at the final stages of a star.

[Noam Hassenfeld]

Carbon, oxygen, nitrogen. The stuff that makes us us.

[Wanda Diasmerced]

The building blocks of life.

[Noam Hassenfeld]

They're made by stars and blown into space when they die. It was almost like Wanda was following in Bob's footsteps. Bob had heard evidence of the creation of the universe and Wanda was hearing the first step in the creation of life. These days, Wanda is an award winning astronomer who's worked at places like the Arecibo Observatory, the Smithsonian, Harvard center for Astrophysics. And she's been traveling around the world trying to tell everyone she knows about sonification.

[Kim Arkand]

I actually had met Wanda at a couple events and was just fascinated by her work and the idea of translating information to sound. And that just set off an inspirational light bulb for me.

[Noam Hassenfeld]

That's Kim Arkand. She's a visualization scientist at NASA's Chandra Observatory, the biggest X ray telescope in the world.

[Kim Arkand]

X ray data is inherently out of the human realm of vision. Right. We cannot see anything besides visible light. And so having X ray images only just seemed like it didn't really make much sense.

[Noam Hassenfeld]

Why not listen instead?

[Kim Arkand]

Why are we not prioritizing other methods of experiencing the universe around us? And so moving into sonification just made sense.

[Noam Hassenfeld]

Kim decided to take some of her data and convert it into sound. Like, here's a sonification Kim made of what might be my favorite space photograph. The Pillars of Creation. You might have seen it before. It's these three towers where stars are created, made up of gas and dust. The sounds you're hearing are based on a combination of the Hubble photograph and X ray data from Chandra.

[Kim Arkand]

It's going to pan from left to right, and you're going to be hearing essentially a mapping of that data as we scan across it. The combination of the beeps and boops, if you will, of that X ray information that's tracing all of those slightly older stars. And then you're also going to hear the sort of texture and structure of those tall pillars of gas and dust in the optical light. So this is the inner Milky Way and this supermassive black hole that's lurking at the core.

[Noam Hassenfeld]

This is another sonification Kim made. It's the galactic center. She combined images from three different telescopes taken in three types of light. There's an image in infrared light, which is below what we can see. There's visible light from the Hubble. And there's an image in X ray light, which is above what we can see. And if you want to listen to this sonification with the visuals, we've got a link in the show notes where you can see it. So please check that out. But, yeah, Kim decided to use different instruments to clearly differentiate between the three kinds of light.

[Kim Arkand]

So in this case, the sounds that we assigned was the piano to the lowest energy from infrared light. Plucky violin for the mid range from Hubble. And then the highest energy is the glockenspiel.

[Noam Hassenfeld]

And the glockenspiel was the X ray.

[Kim Arkand]

That is the X ray light. So you could hopefully hear that little crescendo at the end that is our supermassive black hole. So it's really singing in X ray light, which is, again, very useful.

[Adobe Express Advertiser]

Right.

[Kim Arkand]

This is an image that I had created with some colleagues, and I was so familiar with it, right? So familiar. But the first time I ever heard this piece all the way through, like, I really had to take a moment because it changed how I thought of this data set. I was like, what is happening over there? Like, what is that over there? I never noticed. This is so strong there. How did I not notice that?

[Noam Hassenfeld]

Listening to data like this, it allows you to hear changes in everything from pitch to volume to timbre to rhythm. And you can hear them all at the Same time, listening allows you to pick out one sound to focus on over background noise, like listening to someone you're talking to in a noisy room. And maybe most importantly, it forces you to slow down.

[Kim Arkand]

When I'm looking at a data set, that's an image, I'm looking at all of the data at one time. There's a lot of information for your eye to parse at any particular moment. But if I am listening to data of one of those same objects that I'm used to looking at, I am getting the information over time. And it just, for me, at least, allows me to think through what it is I'm listening to in a very different way.

[Noam Hassenfeld]

But I want to go one step further here. It's easy to think of astronomy as this fundamentally visual thing, you know, this pure idea of just gazing up at the stars. And if I'm being honest, that's how I felt before I started working on this story. I felt like audio was a nice complement to an image. You know, a way to double check it. Maybe a way to get a fresh take on something you've seen a hundred times before, but still secondary.

[Kim Arkand]

It makes sense like it makes total sense. Seeing is believing is a phrase for a reason, right? But so much data from these telescopes is essentially all invisible to us. We are not able to capture it with human vision. So it has to undergo a process of transformation just to get to an image.

[Noam Hassenfeld]

Even when we're not using infrared light or X ray light, images often aren't what they seem. Like that famous photo of the pillars of creation, the pillars aren't actually that red. The red's just a way to tell us there's sulfur there. The greens and blues are just a way to let us know there's hydrogen, oxygen and nitrogen. If you were traveling in a spaceship by the pillars, it would look totally different.

[Kim Arkand]

A lot of the structure that we're able to see in the pillars is existing in non visible kinds of light, which you wouldn't be able to see any of it.

[Noam Hassenfeld]

So what are the real pillars of creation? Is it that famous photo with the reds and greens? Is it a newer infrared photo where there are so many stars that the pillars are almost see through? Or is Kim's sonification just as real?

[Kim Arkand]

To me, sonification is a natural extension of the data because you're just moving it from one form of authentic data to another, right? There's no lack of validity or authenticity because we are moving it from a visual to a sound.

[Noam Hassenfeld]

I've been coming back to this idea over and over again since I started working on this series. By this point, we've spent four episodes talking about how much of the world we hear is constructed by our brain. But it's not just sound, it's all our senses. I think Dan Polley, the tinnitus researcher I talked to, put it pretty well. Because the brain doesn't have direct contact with the physical world, everything that we perceive as consciousness is constructed from the activity of the brain. Sonification is a reminder that no matter what sense we use, we're still going to have blind spots. No representation of reality is more valid or real than any other one.

[Kim Arkand]

I've had multiple people who are blind or low vision approach us and say, I didn't think I could even do astronomy because it's so visual. Sonification of these types of objects has shown me that, like I might be welcomed working for NASA, working at an observatory.

[Wanda Diasmerced]

I had a group of 13 students this summer, and I remember they said, I never thought I would be able to do was by listening to the data that I realized that I can continue forward.

[Noam Hassenfeld]

Wanda's still pushing sonification even further. She's working with the Royal Academy of Science International Trust to launch an Institute for Multi Sensory Science in Lisbon this January. And she isn't just excited about accessibility. She's excited about how scientists want to sonify 20,000 galaxies in order to look for patterns they might have missed. How they're analyzing gravitational waves from merging black holes, how they've even proposed using sonification as a new way to search for dark matter.

[Wanda Diasmerced]

It's exciting to have more people with different skills contributing to the mainstream, studying things that we never thought existed before.

[Noam Hassenfeld]

As I was talking to Wanda, I started thinking back to the very first episode we did on this show about Vera Rubin, the scientist who discovered dark matter. How people ignored her because she was a woman. How she was kept out of scientific institutions, how somehow she never received a Nobel Prize. There were so many moments when she could have just stopped. And if that had happened, who knows? Maybe we'd still have no idea that most of the universe is missing. How many other scientific ideas are we leaving undiscovered because we're making it too hard for different kinds of people with all kinds of perspectives and sensory biases to do science? What might happen if we made it easier?

[Wanda Diasmerced]

People that are not like the current workforce in physics, astronomy, mathematics, the sciences, they will be transformed from beneficiaries to benefactors and to agents of change. If we bring more skills to science, we will have to delete the word limit. The emergence of science would be incredible.

[Noam Hassenfeld]

This was the final episode of our series the Sound Barrier. It was reported and produced by me, Noam Hasenfeld. I also wrote the music, editing by Joanna Solotaroff, mixing and sound design from Christian Ayala, the best kinds of explosions from Sally Helm, and really nuanced detailed fact checking from Melissa Hirsch. Melissa checked so many facts for this series and just made all of it so much better. Melissa, you are amazing. Meredith Hadnot runs the show, Jorge Just and Julia Longoria are editorial directors, and Bird Pinkerton surveyed the scene in front of her hundreds of traitorous platypuses cowering while their former octopus allies stood over them, preventing them from moving. But the Birds had abandoned them and Aaron Bird had vanished. Thanks to Vartika Sharma and Paige Vickers for the beautiful artwork for the Sound Barrier series. Thanks as always to Brian Resnik for co creating the show along with me and Bird. And if any of you out there have thoughts about the show, send us an email. We're@ unexplainableox.com you can also leave us a review or a rating. Wherever you listen really helps us out. And if you're into supporting the show and all of Vox in general, join our membership program. You can go to vox.commembers to sign up. Unexplainable is part of the Vox Media Podcast network and we'll be back next week.

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