Robert Alexander (3:34)

This is Robert Alexander. He's a data sonification specialist that studies the heliosphere, Our sun's sphere of influence in space. Our nearest star is a dynamic and turbulent one. Most scientists turn data about its explosive activity into charts and graphs.

Mike Hartinger (3:51)

Traditionally, we would look at that, and it would be a line that would just kind of boop. It'd go up and come back down.

Robert Alexander (3:57)

Robert translates it into sound Rather than.

Mike Hartinger (4:01)

Just plotting it and looking at it. We can also listen to this eruption of particles. And when we listen to it, it sounds like an explosion. The first time I would play Some of these sounds back For a research scientist, and something that had always been a line on the screen Suddenly was filling the room with this explosive. There's this kind of emotional connection that you can form with it, and it sounds raw, and it sounds powerful.

Robert Alexander (4:40)

In a way, what you just heard there was a coronal mass ejection Exploding out from the sun and accelerating to more than a million miles per hour before crashing into the Parker solar probe, then traveling 14 million miles and arriving at the stereo a spacecraft. How wild is that?

Patti Boyd (5:00)

Our specific community who study plasmas in the near space environment, we actually started using sound Back in the dawn of the space age.

Robert Alexander (5:08)

That's Mike Hartinger, A heliophysics research scientist at the space science institute and NASA collaborator. Before the first rockets Left earth's atmosphere, Space scientists pointed radio antennae up to the sky, Wondering what they might hear, Trying to tune in to the vast universe above them.

Patti Boyd (5:27)

Sometimes it was as simple as, you know, you have an antenna, and you just listen to what's coming out of a speaker in real time. And, you know, you would hear things like whistles. People coined the term whistler waves. You would hear this repeatable pattern every dawn that sounded kind of like a chorus, Like a human chorus. And the term was actually coined dawn chorus.

Robert Alexander (5:49)

When NASA started launching satellites, Scientists heard those waves again, this time from space.

Patti Boyd (5:59)

And so these terms were coined as people were listening to these things through speakers. Just when we were starting to Watch satellites. And if you listen to these things, they're really, like, ethereal. They're really beautiful. And they just make you pause and think, like, wow, that's happening right above my head. And there's this whole invisible world to us that you kind of interact with with sound.

Robert Alexander (6:26)

But what exactly were those early scientists hearing? To understand the sounds of space, we have to start with the stars, Specifically our closest star, the Sun.

Patti Boyd (6:38)

So the sun is a giant ball of gas, really hot gas that we call a plasma.

Robert Alexander (6:43)

From here on Earth, the Sun looks like a giant yellow ball, stable and unchanging. But if you could get up close and zoom in, you know, of course.

Patti Boyd (6:53)

You'Re going to see this giant yellow ball. But if you look at that yellow ball, even through a telescope, you'll see that there are these little dark spots we call sunspots on the surface of the Sun. And they're constantly changing. Like on a time scale of days or weeks, you'll see them kind of pop up and go away, and they'll move as the sun rotates.

Robert Alexander (7:12)

From our point of view, those dark regions, the sunspots, are actually cooler in temperature than the rest of the Sun. But they're also the Sun's most active regions, full of strong magnetic fields.

Patti Boyd (7:25)

You can also see these arcs of plasma shooting out from the Sun. They look like little loops, and you see bubbling plasma coming up to the surface and bubbling up and going back down, kind of circular.

Robert Alexander (7:40)

These sunspots are the launch pads for dramatic outbursts of radiation and plasma called solar flares and coronal mass ejections. When things in those active regions get too hectic, big loops of plasma can stretch away from the sun and break loose from its magnetic fields flying off into space.

Patti Boyd (7:59)

So the sun is dynamic. It's constantly blasting out plasma at different speeds. And this. This plasma kind of just expands out away from the sun into what we call the solar wind.

Robert Alexander (8:13)

On Earth, we live in that solar wind. In the atmosphere of our sun, we're constantly being hit by a blowing stream of particles moving at a million miles an hour. Luckily, we have a shield here on Earth, one that protects us from the relentless solar wind and the sporadic explosions of radiation plasma that come our way from solar flares and coronal mass ejections. And that shield comes from deep within our planet.

Patti Boyd (8:41)

So the Earth has a magnetic field generated in the core of the Earth, the liquid metal core. And basically, from the circulation in that core, you get a magnetic field that kind of looks like a bar magnet.

Robert Alexander (8:56)

If your eyes could see magnetic Fields. When you looked at a bar magnet, you'd see lines coming out of the top or north, north end and looping around to the bottom or south end. Earth's magnetic field looks the same. Those lines are just coming out of the south pole, looping out around through space and going back into the north pole. Earth's magnetic field is why compasses always point north. But it also has a more important role. It extends way out into space until it meets and matches the solar wind coming from the sun, pushing back against it like a cosmic arm wrestling match.

Patti Boyd (9:33)

So you got the solar wind, which has plasma and magnetic field in it, and it pushes against the Earth's magnetic field in plasma, and there's a balance that gets achieved. The region that's dominated by the Earth's magnetic field, we call it the magnetosphere.

Robert Alexander (9:48)

The magnetosphere is an action packed space. It's constantly shifting and changing as its magnetic field, field lines are compressed by the force of the solar wind and explosions of plasma.

Patti Boyd (10:02)

I would say that the solar wind is always changing. It's always kind of tickling the Earth's outer boundary in different ways, you know, vibrating it, tickling it just a little bit. But it's basically staying in that more or less that equilibrium. But then, yeah, when you have a solar wind with some kind of big structure, like a coronal mass ejection, it's like a punch or a big push.

Robert Alexander (10:24)

That all means that what looks like empty space is actually a busy, bustling place full of activity.

Patti Boyd (10:30)

Space is not empty. It's full of charged particles and magnetic fields that are plasma. If you look up in the night sky, you know, as you get maybe 100 miles up in altitude, you start getting lots of this plasma, and it's constantly moving around, it's constantly vibrating. Different types of plasma are constantly interacting with each other. And so all these dynamics or all these behaviors create what I would call a soundscape.

Robert Alexander (11:03)

You may have heard that in space, no one can hear you scream. That's definitely true.

Patti Boyd (11:09)

You know, if you went out into space and you were an astronaut and you took your space helmet off, that would be a terrible idea. But you also wouldn't hear anything.

Robert Alexander (11:16)

That's because here on Earth, what you hear is sound. City traffic, chirping birds, a plucked guitar string, are actually waves of air pressure vibrating your eardrums. Space doesn't have any air, and the pressure's way too low to hear sounds like we do here on Earth. So what Mike's saying about a soundscape in space might sound a bit Wild. But in the sun's atmosphere of low density plasma, other sorts of waves can travel. Plasma waves with electric and magnetic fields we can detect. You definitely couldn't hear those plasma waves in the same way that you hear sounds on Earth. Your eardrum can't detect electric and magnetic fields, but these waves behave a lot like the sound waves we're familiar with.

Patti Boyd (12:00)

In fact, we mathematically redescribe them the same way we describe very similar way we describe sound waves on the Earth's surface. You can think of the Earth's magnetic field, those kind of magnetic field lines on a bar magnet. If they vibrate, they're kind of like vibrations on a guitar string. So they're a lot like sound waves. We just can't hear them with our eardrums.

Robert Alexander (12:18)

When those waves collide with Earth's magnetic field lines, they cause vibrations called resonances. Just like a guitar string wiggling back and forth after you pluck it. When a NASA spacecraft flies through the same spot, we collect a lot of data that scientists can print out on charts, squiggly lines representing those waves visually. But they can also play them aloud. It's a process called data sonification. That's where Robert Alexander comes in.

Mike Hartinger (12:46)

So I take data from the sun in the heliosphere and turn it into sound. If we were to go into an old school recording studio, we would be recording on magnetic tape. So we've got the lead singer of the band, they're laying down the vocals. We've got the bassist, we've got the drummer. We're recording all these instruments on magnetic tape. And then to play it back, we take those magnetic recordings and then turn them into electrical signals, and then use those electrical signals to move a speaker.

Robert Alexander (13:15)

Cone to record earthly sounds. You use a microphone to turn pressure waves into magnetic and electric ones. To listen to space sounds, you can do the opposite. You convert electromagnetic waves to pressure waves.

Mike Hartinger (13:29)

We can hear out there in space all the time. We have satellites that are gathering magnetic measurements from the sun in the heliosphere. So I like to think of satellites as kind of like the most expensive fancy recording studios that are floating out there in space, just basking in all these rich data sets, gathering the greatest hits of the sun. And for me, I think of NASA's data archive like an old dusty record collection.

Robert Alexander (13:58)

Ten years ago, Robert teamed up with NASA's Goddard Space Flight center and scientists at the University of Michigan to do just that. Dig into the data, pull out the records, and help scientists listen to the music of the sun.

Mike Hartinger (14:12)

When I first started working with the Solar Heliospheric Research Group. I walked in the room, and they would put plots up, and they'd have these massive spikes in things like the velocity of the solar wind. And they would get so excited and so geeked at these plots. But for me, I didn't have the same background that they had. So for me, sonification was. Was a really helpful tool to be able to translate their enthusiasm from their domain into this more universal language that I was able to understand.

Robert Alexander (14:42)

Robert's a scientist, but he's also a composer. So he started by listening to the sun as an instrument and exploring it through music. In the sonification you're hearing, the whooshing is generated by changes in the solar wind's velocity, and the layers of voices represent changes in temperature. When it gets hotter, the voices get higher in pitch. And can you pick out the explosions? When a coronal mass ejection, or cme, happens in the data, everything gets louder. That's a lot of information packed into music. And then the research team posed a challenge. They asked Robert if he could listen closely enough to the sun to discover something totally new.

Mike Hartinger (16:04)

And in a moment of inspiration, I thought, what if I take these data streams and I write it directly to an audio file? And I remember I was sitting in a coffee shop the first time that I listened to this.

Robert Alexander (16:16)

The sun is really turbulent. So to find order in the audio chaos, Robert first had to filter out some of the background noise. Once he did, he heard a pattern, a hum.

Mike Hartinger (16:33)

So I'm listening to data, and I was sure that I had made some mistake in my calculations because I kept hearing this noise in every one of my files, and I was like, oh, man, I got the numbers wrong. I got to go back and do all this again. And as I continued listening, I thought to myself, what if this is actually a feature in the data rather than some kind of error in my calculation? And so I went back and I crunched some of the numbers, and it turned out that the hum that I was hearing was exactly correlated with the solar rotational period, which is around 26.5 or 27 days. And so what I was hearing was the rotation of the sun. I remember I messaged my friend. I had a little message window open. I was like, oh, my gosh, I'm hearing the sun rotating. So there we're listening to 60 years worth of of solar rotational data. And the rise and fall of that hum correlates with the rise and fall of solar activity with what's called the Solar cycle.

Robert Alexander (17:32)

Right now we're nearing the peak of the solar cycle and seeing more and more sunspots, solar flares, and coronal mass ejections in the data. Robert realized he could hear those features on the sun disappearing and reappearing as the sun rotated.

Mike Hartinger (17:47)

When we have just one feature that rotates around on the sun, we get the fundamental frequency, which is that 27 day rotational period.

Robert Alexander (17:56)

Then Robert started to hear something else in addition to that fundamental frequency sound. As more sunspots and activity appeared, something that sounded a lot to the trained composer, like music.

Mike Hartinger (18:08)

I realized not only can I hear the rotation of the sun, but I can hear harmonics above this fundamental frequency.

Robert Alexander (18:15)

Listen closely. Do you hear the solar wind's music?

Mike Hartinger (18:20)

When we get two regions that rotate together on opposite sides of the sun, we get an octave above that fundamental frequency. If we have three regions, they're now, if you kind of visualize it, they're equally spaced in thirds around the sun. And this creates an octave and a fifth. And above that we get two octaves, and then we get the major third and the fifth. This creates these musical harmonic components in the solar wind. When you listen closely to the audio, you get this above the. And then depending on how much of the turbulent noise you filter out, you can hear the higher order harmonics. I go back and I take these results and I show them to the research group and they're like, oh, yeah, of course they're harmonics. It's a part of the way that the magnetic field superimposes itself over the sun and that heads out and into the solar wind. And still just my mind was blown. It's like you can hear the harmonic series in solar data. It's crazy.

Robert Alexander (19:40)

Robert had started out by trying to turn the sun's sounds into music, but it turns out the sun makes music of its own. And while listening to the sun's harmonics, turning the solar data into sound, Robert and his team made a new discovery about the solar wind that scientists had never seen. By simply looking at the data, by measuring the strength of these harmonics across elements like oxygen and carbon, they produce the most sensitive diagnostic of the electron temperature of the solar wind ever recorded.

Mike Hartinger (20:11)

And there I got the rush, you know, the adrenaline rush of the realization that we can listen to sounds from the sun and make new scientific discoveries that expand our understanding of the sun and of the heliosphere.

Dallas Taylor (20:28)

But this was just the beginning. Soon after, Robert and Mike launched a project where everyday people could help study solar wind and the Earth's magnetic Field field. And to find the hidden patterns in that data, they needed something way more powerful than algorithms or human ears. That's coming up after the break. This episode is sponsored by Incogni. Right now there are hundreds of so called data brokers trying to collect and sell your personal data. This includes your home address, phone number, location history, and even details about your family members. That data gets bought, resold, and sometimes lands in the hands of scammers and criminals. But the worst part is that trying to take back control of your data by yourself is almost impossible. That's where Incogni comes in. Incogni automatically contacts data brokers and forces them to delete your personal information. Of course, data brokers never stop collecting. That's why Incogni keeps working in the background to prevent your data from getting picked up again. And it's all fully automated. Once you sign up, you can rest easy knowing that your personal information is protected. Get an exclusive 60% discount on Incogni and a 30 day money back guarantee at incogni.com 20k that's incogni.com20k incogni.com 20k Congratulations to Debbie Kavanaugh for getting last episode's Mystery sound right. Those sounds came from a pair of black footed albatrosses, a species of seabird that can be found across the Northern Pacific. These two birds are doing a courtship display which involves a variety of brays, whistles and bill clattering. And here's this episode's mystery sound. If you know that sound, tell us at the web address mystery.2000.org. Anyone who guesses it right will be entered to win one of our super soft 20,000Hz T shirts. Finally, a quick reminder that 20,000Hz is produced out of a world class sound design studio called Defense Defacto Sound. If you make any kind of video content and want it to sound amazing, then take a look@DefactoSound.com, which is my company and it subsidizes 20,000 hertz. So working with Defacto means supporting 20,000 hertz. As a business owner, I've learned that hiring isn't just about filling a position. The right hire can transform your business and the wrong one can slow everything down. Luckily, with Indeed, you can find the right hires fast. Over three and a half million employers around the world use Indeed to find talent. And with Indeed's sponsored job option, your post moves to the top of the page so candidates see it first. It makes a huge difference according to Indeed's data sponsored jobs get 45% more applications than non sponsored ones do. Here's how fast Indeed really is. In the time I've been talking, 23 hires have been made on Indeed worldwide. There's no need to wait any longer. Speed up your hiring Right now with Indeed, 20,000 Hertz listeners will get a $75 job credit. To get your job's more visibility at indeed.comhertz just go to indeed.comhertz right now and support our show by saying you heard About Indeed on 20,000Hz Indeed.comHz terms and conditions apply. Hiring Indeed is all you need. I love a good life hack. If something saves me time or makes things simpler, I'm in. And when it comes to running a business, there's one hack that you definitely need to know about, and that's NetSuite. NetSuite brings your accounting, project management, inventory, HR and more into a single platform. So instead of juggling separate programs for all of these, you get one. As a business owner, I can tell you that having a unified system like this will save you a ton of time and effort. NetSuite also offers real time insights and forecasting tools. That means faster decisions, better planning, and less time wasted on busy work. So when new opportunities arrive, you're ready to act. Over 40,000 companies have future proofed their business with NetSuite, and it's easy to see why. NetSuite helps you respond to immediate challenges and seize your biggest opportunities. Speaking of opportunity, download the CFO's Guide to AI and Machine Learning at netsuite.com 20k. The guide is free to you at netsuite.com 20K netsuite.com 20k.

Robert Alexander (25:24)

If you could listen to a star, what would you hear? Robert Alexander and other NASA experts are doing just that, listening to our sun to learn its secrets through a process called data sonification. Heliophysicists are used to reading charts and looking at stunning images from spacecraft. But more recently, they've discovered that by closing your eyes and trusting your ears, you can discover things you never could have seen. Today, Robert's part of a new NASA citizen science project alongside heliophysicist Mike Hartinger, trying to make new discoveries by listening to the sun. It's called haarp, short for Heliophysics Resonances in Plasmas.

Patti Boyd (26:06)

So we love acronyms in heliophysics. Scientists just love acronyms, right? So our acronym is harp, and we're studying basically a massive magnetic HARP in outer space where if you look at the Earth's magnetic field you can kind of look at it from the perspective of a harp, where the harp strings are short, close to the Earth, because the Earth's magnetic field lines are short. And if you move away from the Earth, these magnetic field lines or magnetic strings get longer and longer. And the analogy is really, really pretty exact because you definitely hear the pitches of these waves get lower and lower as you move away from the Earth.

Robert Alexander (26:43)

To study Earth's magnetic harp, the team is using data from a satellite called Themis.

Mike Hartinger (26:48)

And liftoff of a Delta II rocket.

Robert Alexander (26:51)

Carrying THEMIS, NASA's revolutionary journey to study the Northern Lights.

Patti Boyd (26:56)

And it looks kind of like a box, and it's this box that's spinning. It's got all these sensors and it's measuring magnetic fields as it's going all the way around on its orbit.

Robert Alexander (27:08)

As the THEMIS satellite orbits Earth, it flies through the different strings of Earth's magnetic field, picking up the resonances the solar wind creates when it hits them and plays them, like plucking a harp string.

Patti Boyd (27:20)

To study a harp, you need to basically pluck all the different strings.

Robert Alexander (27:23)

Luckily, THEMIS is set up to do that. It has an elliptical orbit, sort of like an oval shaped path it takes around the Earth.

Patti Boyd (27:30)

And that's good for us because we want to study this harp, an elliptical orbit. You can basically run across the whole harp and hear all those different pitches, all those different strings. And what you'll see then is as the satellite moves away from the Earth on its orpit, you'll hear a descending tone. And then as it moves back towards the Earth, you'll hear the tone come up in pitch. It's kind of going back and forth along the harp.

Robert Alexander (28:04)

That's a perfect ideal harp sound.

Patti Boyd (28:07)

Of course, in a real event, you're going to hear all kinds of different stuff. You're going to hear on top of that, crunches, you're going to hear all kinds of chirps and other things happening. And that's part of why we want to work with volunteers to pick out these really unique patterns that change from day to day.

Robert Alexander (28:22)

The THEMIS satellite has been collecting data for over 15 years. That's a lot of sun data. But don't worry, it doesn't take that long to listen through it. As a volunteer, the waves HAARP is dealing with are ultra low frequency, like most waves from the sun, which means they're so low in pitch that you can't hear them normally. The team speeds them up so they're in the frequency range your ears can hear, which has the added benefit of letting you listen through hours, even days of data in seconds.

Patti Boyd (28:52)

You know, we have a lot of research that's been done. You know, individual scientists over the years and groups of scientists have learned a lot about these waves. We've learned about the types of instruments that are in this kind of symphony in the nearest space environment. We've learned that there are things like the harp or like these magnetic strings or guitar strings. We've learned there are things like a drum, like that outer boundary that the soar one is pushing on is kind of like a drum. You can tap on it and you'll play different pitches or different types of pitches.

Robert Alexander (29:20)

Scientists have identified many of the different instruments in the solar symphony, but they don't yet understand its music. All the different combinations the symphony can play in the patterns and pitches and amplitudes and intensities that can tell us so much about the solar wind and magnetosphere.

Patti Boyd (29:37)

There are all these patterns that are there that if someone just listens to the data, they pick out right away. You know, you listen to a year's worth of data, you'll ultimately find find these complex but repeatable patterns in the sound that you wouldn't have known to look for if you just looked through visually. So that's why we need people's help. They can go through a lot of data fast. Getting more people's ears on the data and eyes on the data too, because you can also see the data on our website. So the more people that can look at this, the better.

Robert Alexander (30:02)

Your ears and eyes are a lot better than computers at finding patterns in HAARP data. Citizen scientists listening to harp sounds have already made a new discovery, a unique reverse harp sound that researchers didn't expect at all. Can you hear the difference? Sonification has also revealed a new sound in the solar wind and magnetosphere Data that's not harp like at all, but one that may sound familiar. Here's Robert again.

Mike Hartinger (30:42)

A lot of features in the solar wind sound like chirping birds. There is an analysis example from the THEMIS satellite where there were these big features in the spectral plot. And there's this tiny little feature up top that wasn't really visually interesting, but when we played it back, we heard this kind of chirp, chirping bird sound. So we hear that kind of.

Robert Alexander (31:12)

That sound turned out to be several types of wave superimposed in the magnetosphere. A rare find. It's a lot harder to pick that phenomenon out by looking at a chart.

Mike Hartinger (31:23)

And the reason why it stuck out in auditory analysis was because it was just acoustically interesting. Like you don't expect to hear a bird chirp in the middle of your magnetometer data, your electric fields data. So that tells us that there's something unique that's going on.

Robert Alexander (31:41)

As human observers of the universe, we can use our senses together, sight and sound, to better understand our life giving star and the space beyond.

Patti Boyd (31:51)

One thing I always tell people about this is, you know, magnetic and electric fields and the stuff that we study is invisible. And it's equally valid to use sound as to use visual. I mean, we use visual representations of things like graphs with like wiggly lines, but there's no, it's arbitrary, right? Like there's no reason you have to interact with that data visually. You can totally do it with sound. And there's, it's an equally valid way of interacting with it. And in fact, you see different patterns with both of those. You know, if you go outside any given day and you close your eyes and just listen to what the birds are doing without even opening your eyes, you can tell what's going on. You can tell if there's a hawk that just flew by, you can tell if there is a nest nearby, you can tell if a human is walking by. I mean, and I think it's the same with space sounds. You can learn so much about the environment just by listening to these sounds played through a speaker.

Robert Alexander (32:45)

The more tools we have at our disposal to study waves in space, the more accessible science becomes better, including scientists and citizen scientists who have limited vision or hearing. Science, like space is for everyone.

Mike Hartinger (33:00)

When we use our eyes, we can pick up certain things from a plot or a graph. For a lot of people, they see a graph and it just kind of shuts them off. When we listen to an audio file, it tends to pique our curiosity and we can pick out a whole slew of other details. We can hear the glistening high frequencies and rumbling low frequencies. When we get up out of bed in the morning, we don't decide am I going to use my eyes or my ears today we live in this multi sensory world and by turning data into sound, we're just using a sense that's more optimized for frequency analysis to conduct frequency analysis. I think it's incredibly important that human beings have this very intimate connection with the data that's gathered by satellites. Just like stethoscopes allow doctors to hear the human heart, we now have these satellites that allow us to listen to the heartbeat of the sun. And I think so much of the investigation that takes place is driven by. By human intuition. And our human intuition can be an invaluable tool when it comes to the process of scientific research. The sun sounds like a lot of.

Patti Boyd (34:23)

Different things, like really low buzzing.

Mike Hartinger (34:29)

Kind of like when you're like lifting.

Patti Boyd (34:31)

Off on the plane or like when.

Robert Alexander (34:35)

A jet's taking off.

Mike Hartinger (34:38)

Or maybe it sounds like a lot of rain falling down. Sounds kind of like a lot like fire.

Patti Boyd (34:47)

Maybe a fire or birds flying.

Mike Hartinger (34:51)

Like if you turn your head in a certain way or stick it out.

Robert Alexander (34:55)

Of a window and the wind goes.

Mike Hartinger (34:58)

On, it sounds kind of like that too. Sandstorm. You guys are all right. So it sounds like a rain filled fiery sandstorm, right?

Patti Boyd (35:07)

What's that? Stampede of elephants?

Mike Hartinger (35:11)

So the stampede's coming and then here comes a sandstorm and then we get the hum of the wind and then the rain. Wow. Thank you, guys.

Dallas Taylor (35:31)

That story came from NASA's Curious Universe, an official NASA podcast that takes you on mind blowing adventures in science and space. In one episode, they explore how the Clipper probe will search for signs of life on Jupiter's icy moon Europa. In another, they unravel the mystery of a strange space rock with Radiolab's Latif Nasser. Subscribe to NASA's Curious Universe right here in your podcast player. 20,000 Hz is produced out of the sound design studios of Defacto Sound. Hear more@defactosound.com this episode was written and.

Robert Alexander (36:04)

Produced by Christian Elliott. Our executive producer is Katie Konins. The Curious Universe team includes Jacob Pinter, Maddy Olson and Mikayla Sasby. Our theme song was composed by Matt Russo and Andrew Santaguida of System Sounds. Special thanks to Alessandra Pacini at noaa, Denise Hill and the NASA Heliophysics team. All the HAARP project volunteers who sent us voice memos. Kirsty Beaton for her harp music for the Harp project. Henry Dellinger for the use of his Cosmic Cycles Symphony. And scientists at the British Antarctic Survey and the University of Iowa's Space physics department studying space weather. For the whistler and chorus wave sounds, I'm Dallas Taylor.

Dallas Taylor (36:46)

Thanks for listening.

Robert Alexander (36:52)

Sounds like robot frogs talking to each other underwater.

Mike Hartinger (36:55)

Zippers.

Robert Alexander (36:56)

Zippers underwater.

Mike Hartinger (36:57)

Just very fast.

Robert Alexander (37:01)

Gurgly.

Mike Hartinger (37:03)

Wait, what does gurgly sound like?

Robert Alexander (37:05)

Sounds like here.

Patti Boyd (37:06)

If you get me some water, I'll.

Mike Hartinger (37:08)

Show you I can do it. Three glasses of water on it.

Patti Boyd (37:12)

Take a big breath before you do it.

Robert Alexander (37:13)

Okay. Oh my God.

Mike Hartinger (37:27)

Sorry.

Dallas Taylor (37:30)

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