Check it out! For the first time, you can watch this interview on NASA’s YouTube channel. 

About the Episode

In this special episode, we turn the tables and put host Padi Boyd in the interview seat. Padi shares stories from her time with NASA’s groundbreaking Kepler mission, which showed us many more exoplanets—planets orbiting other stars—than we had previously discovered. She also tells us about her dream astronomical dinner companion and her go-to karaoke song. Plus, we’ll wrap up another season of wild and wonderful adventures by answering questions from listeners like you and sharing behind-the-scenes tidbits from Season 6 episodes.

For the first time, this episode of Curious Universe is also available as a video podcast. Check it out at nasa.gov/curiousuniverse and NASA’s YouTube channel. 

Padi Boyd: Hey, Curious Universe fans. We’re super excited to share this bonus episode with you. Today, the guest in the hot seat is me. I’ll share some of my own story, including researching planets orbiting stars far from Earth, and I’ll help answer questions sent in by you, the listeners. I just want to let you know that we’re trying something new. For the first time. There’s also a video version of this podcast episode. You can watch it at nasa.gov/curiousuniverse or find it on NASA’s YouTube. If you’d rather just listen, well, we’re not going anywhere. Thanks, and enjoy the show.

 

[Theme song: Curiosity by SYSTEM Sounds]

 

Jacob Pinter: I’m Jacob Pinter. I’m one of the producers on the Curious Universe team. And today I get the pleasure of grilling Dr. Padi Boyd. Listeners of Curious Universe will recognize Padi. She’s our host with the most. But what you might not know is that hosting this show is a small part of Padi’s job. She’s a full time astrophysicist. She’s been researching the cosmos for decades. Basically, she does all her own stunts. So Padi, I’ve got tons of questions for you, and I think people who listen to the show are really going to enjoy getting to know the scientist behind the voice. So thank you so much for doing this, for sitting in the hot seat today. It’s gonna be fun.

 

Padi Boyd: I’m happy to do it. And I’m really looking forward to the conversation. So thank you, Jacob.

 

Jacob Pinter: So you’re a scientist. Why don’t you run me through the basics of what you study: what are you interested in?

 

Padi Boyd: So I study how light changes and what we can learn from those changes in light. And so that’s called photometry. That’s the technical word for light changing. And I study changes in light at wavelengths from X-ray to ultraviolet to optical to near infrared. So multi-wavelength photometry. And why is that so interesting? It’s because we can learn so much about these objects that are really far from our hands here on Earth by just watching the patterns and then drawing some conclusions about what’s driving those patterns. So we’ve been doing that for thousands of years as human beings. We looked at patterns in the sky, and we figured out the calendar and the seasons. And then we figured out what the Moon and the stars were doing and the Sun, just by watching these patterns evolve and change and finding periodicities and then putting that together with a model of what’s going on. So use that concept to go even beyond our solar systems. How do we use changes in light to infer what’s going on in things like stars—binaries with a black hole or neutron star in it, even like supermassive black holes at the centers of galaxies beyond the Milky Way?

 

Jacob Pinter: That’s some cool stuff.

 

Padi Boyd It’s really fun. And you’ve got to go to space to get those extra wavelengths that we don’t see with our eyes here on Earth.

 

Jacob Pinter: Well, why don’t you take me back to the beginning? Like, how did you get interested in space in the first place? And then how did you end up at NASA?

 

Padi Boyd: So I was a really big science fiction fan as a kid.

 

Jacob Pinter: Oh, like what?

 

Padi Boyd: I loved Star Trek.

 

Jacob Pinter: Okay.

 

Padi Boyd: I just thought it was a beautiful concept for the future, you know, everyone working together and exploring the universe. So I was really drawn in by that, the science and the philosophy of it. But I also really liked reading books about science fiction.

 

Jacob Pinter: Sure.

 

Padi Boyd: And I liked science programs, like there was a show called Cosmos when I was a kid. That was Carl Sagan’s show and he was basically inviting everyone along on his cosmic journey. So that was like the first astronomer that I knew of, and that just kind of drew me into the field.

 

Jacob Pinter: So one of your research interests now is exoplanets, planets that orbit other stars. And these days, we know that there are a lot of them in our own galaxy or a number of them. But that’s a pretty recent thing that we found out. I’m wondering if you can just take me back to when use started studying exoplanets. What did we know about them at the time?

 

Padi Boyd: So when I first started out in the field, we didn’t have any observations of planets beyond our solar system. We only knew about the planets in our own solar system, and then we were hopeful that there would be planets around other stars. There were good theoretical reasons to think that how our solar system formed is not special and that when other stars formed, it’d be through a similar process and that there might be planets there. But for a long time, it was feared that the planets are so small, and they’re so dark, they don’t give off their own light, that it’d be virtually impossible to be able to detect them with the methods that we had. And then methods got better.

 

Jacob Pinter: Wow.

 

Padi Boyd: And—-yep, we were able to get signals higher and noise lower and started using more telescopes, more telescope time, and looking for different types of patterns in the light. And that opened the field from something that was just basically a dream and a hope from when I started out to where we are today, a few decades later, where we now know there are more planets than stars in our galaxy.

 

Jacob Pinter: Wow.

 

Padi Boyd: It’s just an amazing result.

 

Jacob Pinter: So how do NASA scientists actually find these exoplanets? Like you said, they’re small. They’re far away. For a long time, we thought that they would get drowned out—the light would get drowned out by the star that they orbit, right?

 

Padi Boyd: Totally. Yeah, so the sun is—the light that you see from the Sun, if you were to look at our solar system from outside, comparing that to say, the reflected light on our planet Earth. That’s 10 billion times brighter, the Sun versus the reflected light from the Earth. So you can see why that sounds like a hopeless problem.

 

Jacob Pinter: Yeah!

 

Padi Boyd: But even though the planets are dark and small, they do impact their environment. They show signs of their existence, even though you don’t see them directly. So if they’re massive like Jupiter, their gravity will impact the motion of the star just like the star’s gravity impacts the motion of the planet. It’s kind of a ying-yang kind of thing.

 

Jacob Pinter: So the planet is, what—making the star wobble a little bit?

 

Padi Boyd: Exactly. So the star makes the planet orbit around it. But the planet also makes that star wobble around like their common center of mass if you put them on a seesaw and have them balance out. So that was one way to look, like that star moving towards us and away from us would imprint a signal and a pattern in the spectral data. So that’s how some of the first planets were found through this, what we call radial velocity, or the wobble of the star. But also if you’re lined up really perfectly with that system, then when those planets move in front of the star, the planet, which is dark, will have this tiny dimming effect on the star. It’ll block out a little bit of that light. And so there’s photometry again. Let’s look at how the light changes as a planet passes in front of a star. That’s called the transit method. And that’s how missions like Kepler and TESS find their planets.

 

Jacob Pinter: Well, this kind of leads into what I was going to ask next, because we know that there’s a lot of these planets, right? What else do we know about exoplanets? And how can we figure it out for these planets that again, are small, far away, and can be difficult to detect?

 

Padi Boyd: So we’re really just like scratching the surface right now or the tip of the iceberg. Discovering the planet is like step one on this path. So there are ways to find out more about the nearest planets to us because those are the brighter ones. But we need to special purpose design some instruments and some missions to really go after those faint signals and tell us what we want to know. So like our biggest driving question right now is, how similar is our solar system to other solar systems out there? We know there are solar systems everywhere. Well, how common is the process where life developed on our planet throughout the Milky Way?

 

Jacob Pinter: Basically, like, are we special?

 

Padi Boyd: How special are we? I think one of the things we’re learning is that every solar system is unique, just like every person is unique. But how unique, right? Like we’re all breathing oxygen here. We’re all born, go through those teenage years, evolve. We want to be able to put our solar system in that same kind of context with the other solar systems out there. So the first questions we’re interested in like, you know, what’s the atmosphere like? Even the planets in our solar system have vastly different atmospheres. What about those planets around the other stars? Are they similar to Earth’s atmosphere? What about Venus’s atmosphere or Uranus’s atmosphere? We don’t see life on those planets, so that would say maybe life’s not there. What about water? Clouds, weather, plate tectonics, magnetic fields, the things that we find so important to how Earth and life on Earth co-evolved—how common are those situations out there? And that’s the driving question for all of our technology going forward for exoplanet hunting.

 

Jacob Pinter: Do you have a favorite exoplanet of the, again, very many that there are? And if you do, can you tell me about it?

 

Padi Boyd: It’s a really hard question. Because like we were saying they are all unique, right? If you’re really curious, there’s something to love about all of them. But I think the one that I find so excited that it’s there is one called Proxima B.

 

Jacob Pinter: Okay.

 

Padi Boyd: The nearest star to our Sun is the Alpha Centauri system. And that’s actually not just a single star, it’s three stars. Two of them are pretty bright, Alpha Centauri A and B, as we call them. And then there’s a tinier star—very small compared to our Sun or Alpha Centauri A and B—but it’s on an orbit around those two that brings it very close to—not very close but closer to Earth than A and B. And so that’s why that’s called Proxima Centauri. It’s the proximate one to us. We know that there’s a planet around Proxima B. And we know it’s in what we call the habitable zone, or Goldilocks zone, of that star, where the conditions are right that liquid water could exist on the surface. Could, could not.

 

Jacob Pinter: I mean, the habitable for people zone?

 

Padi Boyd: Well that’s a very different question. But that’s one of the cool things—

 

Jacob Pinter: Now I’m just like opening a whole door.

 

Padi Boyd: These are great doors to open, though, you know what I mean? Like, we’re starting to take that step through the door. The habitable zone is just a place around a star, where if there were a source of water, it could stay liquid on the surface. It wouldn’t all freeze up, because you’re too far away from the energy of the sun. It wouldn’t all boil up, because you’re too close. It could stay liquid for a while. That’s one condition, is having water on the surface. But that’s definitely not the only condition. And so now we get to put sort of like the details on that question. What does it mean to be habitable? It’s not just that zone. How do you have the other conditions where biology on the surface can actually flourish?

 

Jacob Pinter: And I would have to think, given that we’ve learned so much about exoplanets in a pretty small amount of time, seems like one of those fields where we’re going to look up in another 25 years or something and say, Man, back in the 2020s, we just didn’t know what we didn’t know.

 

Padi Boyd: I think so too. I mean, we’re really just taking these first steps. So we’re definitely going to be able to put a lot more information on these exoplanet systems as we go through this decade and the next. It’s going to be a great time for the explosive growth. It already is.

 

Jacob Pinter: You know, I think for a lot of us who aren’t scientists, like when we picture scientists wearing their lab coats looking through a microscope or a telescope or whatever, what we really picture is that eureka moment when you find a breakthrough, or just you discover something totally new or something like that.

 

Padi Boyd: Right.

 

Jacob Pinter: But can you kind of take me into what that is actually like in reality? Like, is there one breakthrough or discovery or something that you can, you know, tell me the story of and sort of put me in, like, what does it feel like? And how does that actually happen?

 

Padi Boyd: Okay. So that’s cool that you brought up that stereotype of like, the lone scientist in the coat, looking through the telescope or the microscope and having that moment of “aha”, and everything changes.

 

Jacob Pinter: The lightbulb goes off.

 

Padi Boyd: The lightbulb goes off. And that has definitely happened. But what we’re seeing more and more is that science done by teams of people and that, you know, each individual person brings their own unique strengths to a broader team, and that that team working together can accomplish a huge amount. I think we tell that story so well in our Curious Universe episodes across the spectrum of what we do here at NASA. But the personal experience I had like that came with the Kepler mission. Kepler launched in the end of the first decade of the 2000s. And it was the first NASA mission that was specially designed to study exoplanets because they were so new.

 

Jacob Pinter: Okay.

 

Padi Boyd: And at the time, we only knew of a couple hundred, and they weren’t mostly found with the transit method. Kepler was meant to do photometry, like we were talking about before, on 100,000 stars at one time.

 

Jacob Pinter: Wow.

 

Padi Boyd: Looking for those tiny dips or something that could be a dip. Those transit signals would first give us a signal and all that data that we would call—would have to cross this threshold to be interesting.

 

Jacob Pinter: Okay.

 

Padi Boyd: So we called those threshold crossing events.

 

Jacob Pinter: You said you’re talking about 100,000 planets? Or 100,000 stars?

 

Padi Boyd: It was an unprecedented computational task. A hundred thousand stars, all that data coming down at once, and you’re shoving it through this pipeline.

 

Jacob Pinter: So you’ve like really got a fine-tooth comb to go through all this, right?

 

Padi Boyd: Yeah, that’s a great analogy. And you’re throwing most of that stuff away. You’re really sifting through it to find the interesting stuff. And at the time Kepler was launched, we didn’t know how common or rare exoplanets were. That was one of the big questions it was meant to answer. And we were kind of, you know, worst case scenario-ing it. What if Kepler didn’t find any transiting planets or very few orshowing that, you know, planets just weren’t very common in our galaxy? So we were ready for like a certain number of threshold crossing events. And when that first data slug comes down to the ground, it goes through that pipeline, and the team starts looking to see what they got, there’s a lot more threshold crossing events than anybody expected. And so the first thing you think is like, Oh, what did we do wrong? Right? What’s wrong with these programs? What could possibly be giving us these false positives, these threshold crossing events that shouldn’t be there?

 

Jacob Pinter: Right.

 

Padi Boyd: But at the same time, when you’re looking for, like, what could we have possibly done wrong? How do we explain this, in making sure we’re not making any mistakes? There was that ray of light at the same time, that maybe we’re getting so many threshold crossing events because every star in this collection has a planetary system. And so the ones that we can’t see transit are just the ones that aren’t lined up for us. And the ones that are lined up, well we’re seeing threshold crossing events are a huge proportion of them are showing us something like a threshold crossing events. That’s what the statistics were telling us from that very first moment. It could be that planets are everywhere. Could be. And then just to see how those years—so that’s the aha moment, right?

 

Jacob Pinter: Yeah, oh yeah. That’s a big aha moment.

 

Padi Boyd Because you want to think, what could I be getting wrong? Don’t want to get this wrong. So you’ve got to go through all that. And I think that’s part of the aha moment too. Like, “Mm this can’t really be right, is it?” But then also that spark of Oh, my goodness, what if—

 

Jacob Pinter: What if it is?

 

Padi Boyd: What if this is the best answer we could have ever hoped to get?

 

Jacob Pinter: Right. Wow. So Padi, I have to ask you about something that I know about you that I think our listeners probably don’t know about you. And that is that you’re a great singer.

 

Padi Boyd: Thank you!

 

Jacob Pinter: And you’re in this band called The Chromatics that sings about space.

 

Padi Boyd: We do.

 

Jacob Pinter: So I think the people need to know about this. Tell me about it. Tell me how you got started with it. Tell me about the chromatics.

 

Padi Boyd: Okay. Sure. So we are an a capella group. We don’t sing with instruments. We sing music with our voices only. And we’re a smaller a capella group. So there’s six of us. And so many of us come from NASA. We’ve met through NASA. We met through a music and drama club. We accreted people who were space nerds just like us, even if they didn’t work here. And so when we realized that many of us could sing things from our childhood, you know, like Schoolhouse Rock or even commercials telling you like what’s in a product—you could sing the song from your childhood, and you remember exactly what you wanted to eat that day. We wanted to take that idea that music can really like bake those ideas into a mind and share some of the most exciting things about science, astronomy, telescopes, what’s out there in the universe, and how we know it, and put those in songs. So that’s what we do. We call that Astro Capella. Because it’s astronomy through a capella. And we’ve been doing that for the whole time the group has been together. And we’d like to sing about missions. We like to sing about black holes and the habitable zone, the Goldilocks zone. There’s a song about that. And we do activities for students that can be used in the classroom, too. So sometimes we’re working with teachers to get that content into a type of lesson plan that can be taught. And other times we’re it museums just participating with any activities at a museum and working with the general public and singing to them. Singing songs of science.

 

Jacob Pinter: It’s like that little spoonful of sugar that helps the astronomy go down.

 

Padi Boyd: That’s a good way to look at it.

 

Jacob Pinter: All right. Well, Padi, to cap off, I’ve got to ask you the question that we ask everyone we interview. This is something again that listeners may not know, but you know, the name of the show is Curious Universe, we really try and follow their curiosity. So to end every single interview, we ask: Padi, what are you still curious about?

 

Padi Boyd: I am still curious about our model of the universe and how it began and how it’s going to evolve.

 

Jacob Pinter: Okay. That’s a big, heady thing to be curious about.

 

Padi Boyd: Yep, our whole universe.

 

Jacob Pinter: Yeah!

 

Padi Boyd But we’re learning so much in the next couple years. You know, we’ve got JWST that’s finally looking beyond what we were able to see with our telescopes before it came, finding those first galaxies and how evolved they are and what is that telling us about our models. But also like, what’s the Roman telescope gonna tell us when it gets up and starts really interrogating things like dark matter and dark energy, parts of our universe that we know are so important to its evolution and its future that we can’t really measure well yet? So I’m looking forward to answering those big questions in both directions, the beginning and the evolution and how NASA space missions are going to impact that.

 

Jacob Pinter: All right, if you’re up for it, I’ve got a lightning round of quick questions to run through. This will be fun, I think. All right.

 

Padi Boyd: I’m going to ask you the same ones.

 

Jacob Pinter: Let’s go.

 

Padi Boyd: All right.

 

Jacob Pinter: First up. If you, Padi Boyd, could go to space, would you do it?

 

Padi Boyd: I would totally go to space. I think it’s such a special—

 

Jacob Pinter: No hesitation.

 

Padi Boyd: No hesitation. I’d love to see the Earth from that vantage point. I know it’s life changing for everybody who’s been. I want to experience that myself and it’d be fantastic.

 

Jacob Pinter: Okay, Star Wars or Star Trek?

 

Padi Boyd: I gotta say I’m a Star Trek fan more than Star Wars.

 

Jacob Pinter: And even—as a Star Wars person, is there anything I can do to change your mind?

 

Padi Boyd: So I love them both. You know, I really enjoy the planets that they visit and all the things they have in common there. I like the philosophy of Star Trek a little bit better than the swashbuckling Star Wars. But I think you’ve given it away. Yeah. What about you, Jacob?

 

Jacob Pinter: Yeah I would pick Star Wars. It’s really just the lightsabers. They’ve got me. I want to do cool sword fights.

 

Padi Boyd: Yeah. It’s pretty cool.

 

Jacob Pinter: You’re a singer. What’s your go-to karaoke song?

 

Padi Boyd: Oh. So I like any Linda Ronstadt song.

 

Jacob Pinter: Ohh.

 

Padi Boyd: Yeah. So I’ll go with “You’re No Good”.

 

Jacob Pinter: “You’re No Good”! Yeah!

 

Padi Boyd: Yeah!

 

Jacob Pinter: Well Padi, thank you so much for playing along. This has been super fun. You know, all season, we’ve been asking listeners to send in their questions. Because even though there’s a lot that we’re curious about, we love it when you send us down the rabbit hole too. And you know, we don’t have time to answer every single question. But just like we promise every season, we do our best to track down the answers to your questions from experts across NASA. So Padi, I’ve got some questions. I’m gonna tee them up. And I’m hoping you can help me answer these because you’ve got a lot more expertise than I do.

 

Padi Boyd: I’ll do my best.

 

Jacob Pinter: All right. If you’re all set, the first question comes from Instagram from named R-I-Z-S-F-P. Are there many black holes in outer space?

 

Jacob Pinter: Wow.

 

Padi Boyd: Then you talk about the small black holes. There are not as many massive stars out there as there are stars like our Sun or smaller. So about one in a thousand stars in our galaxy would end its life as a compact object, a stellar sized black hole. And there’s about 100 billion stars in our galaxy. And if one in 1,000 will end its life as a black hole, that’s about 100 million black holes in the Milky Way, just the Milky Way, these small stellar mass black holes. They’re really hard to detect. So even though we’ve been looking for stellar mass black holes and we know that there are some out there and we’ve been studying them, we only know about a couple of dozen at this point in time. We’ve discovered them, but we know the other ones that are there from inferring what we know.

 

 

 

 

 

Jacob Pinter: All right. Our second question is also sort of astrophysics related. So also sort of up your alley. It’s also from Instagram from a user named Code-Q-code-5280. And it’s deceptively simple, I think. The question is, what is the speed of darkness?

 

Padi Boyd: What a cool question. I love the way that sounds. It sounds like it should be a movie or a song or an episode of Curious Universe. So the speed of darkness—you have to put in the context of the speed of light. The speed of light is the fastest that anything can go. And darkness is the absence of light. So if darkness is us taking light away, or light passing by, then the speed of darkness would be equivalent to the speed of light. There are all kinds of, like, thought experiments that can give you the illusion of darkness maybe moving faster than light. So you can imagine like if there’s a little, you know, ant moving across a light source. And then if you were to think about its shadow that’s further away, that shadow would look like the ant is moving faster—you’d see the shadow moving faster than the actual ant on the light source because it’s being magnified, right?

 

 

 

 

 

 

 

 

 

Jacob Pinter: Okay, a good answer. All right. Well, our last question comes from a listener in Argentina, who actually recorded an audio version of their question. So let’s take a listen to this one.

 

Padi Boyd: Great.

 

Gabriel Fuselli: Hi, my name is Gabriel Fuselli. I live in Santa Fe, Argentina. I’m a big fan of your podcast. I’ve been really curious about the universe since I was a child. So if I could ask to an astronaut or an astrophysicist, it would be: which are the procedures that astronauts must follow before and during a spacewalk? So thank you very much!

 

Padi Boyd: That was a great question. Thank you Gabriel, for your question. And as you know, a spacewalk is any activity that astronauts do in space when they’re outside the spacecraft. There are a lot of steps to properly suit up for a spacewalk. And we checked in with an expert at the Johnson Space Center who told us something you might not know.

 

Jacob Pinter: Which is?

 

Padi Boyd: Well astronauts do something called In-suit Light Exercise, or I-S-L-E. It’s when they move their arms and legs around like a dance to purge their blood nitrogen. Did not know that. And this helps reduce decompression sickness when they go into the vacuum of space. Also, when on a spacewalk, astronauts have to climb aboard portable foot restraints. You turn a screw, your whole body will rotate in space. So these keep your feet stuck in place. And they might have two to three different work sites depending on what they’re doing. Throughout the spacewalk, they’ll often stop for spacesuit inspection, making sure their gloves aren’t starting to get holes in them, and that their helmets and pads feel dry.

 

Jacob Pinter: Wow. That little—I forgot what the acronym was—but the little dance you have to do to get the nitrogen out of your blood. It’s something I never thought about, you know.

Hearing what our listeners are curious about, I’ve got to say is one of the best parts of working on this show, because there’s so many questions and so little time. But if you’ve been listening along, we’d love to know if you could ask a NASA scientist or astronaut anything—I mean, like dream big here. If you could ask them anything, what would it be? Well, you can send us your question to NASA-curiousuniverse@mail.nasa.gov. And we’ll do our best to track down the answer. We may even get to answer your question in an upcoming episode.

 

Well, here in our sixth season of Curious Universe, we went to some mind blowing places. And this season had a few firsts for our team. For instance, we were able to travel out to Utah. Our producer, Christian Elliot, gathered on-the-ground recordings of the sample return of OSIRIS-REx. This was the first time that NASA collected a sample from an asteroid and brought it here to Earth. So let’s take a listen from that episode.

 

[clip from “Special Delivery from Outer Space” episode]

 

Richard Witherspoon: All stations I have visual on SRC under main chute.

 

CHRISTIAN ELLIOTT: We watched from mission operations as the surveillance plane cameras tracked the bright orange parachute through the blue sky. Then we lost sight of it, as the capsule disappeared behind a hill… we couldn’t tell if it was safe.

 

Utah Test and Training Range radio: …over the horizon. Oh and it touched down.

 

Richard Witherspoon: All stations we have visual confirmation of touchdown, however it went down behind a hill so we do not have …

 

CHRISTIAN ELLIOTT: Mike and the other engineers and scientists were on the edge of their seats again. It took several minutes for the helicopters to fly across the huge ellipse.

 

Recovery command announcer: Recovery operations. Helos one and two are in the area of the landing site.

 

CHRISTIAN ELLIOTT: But once they did, they could see the capsule sitting there with the parachute on the ground next to it, right next to a service road on a dry, flat patch of ground, just as the team had hoped. It was a perfect, gentle landing. Finally, everyone relaxed a bit.

 

[end of episode clip]

 

Recovery command announcer: Helo 2 has visual confirmation of SRC. I repeat, the SRC has been located.

 

Padi Boyd: Jacob, you and Christian, were out there to support the OSIRIS-REx team sample return, what was it like being on-site during this historic NASA moment?

 

Jacob Pinter: It was really cool to be there. And the moment that I’ll never forget was after the capsule had landed and we knew it was safe and we knew that, you know, everyone was going to be happy, and the science was going to be able to proceed. The capsule had actually landed in a spot that was it was off in the distance where we cuoldn’t see. And so after that, the helicopters retrieving it just sort of appeared out of the mountains in the distance. And one of them had this long cable with a kind of basket thing that was carrying the capsule. And we saw it, again, just come out of the horizon, fly towards us, come right in front of us, and go to where they had set up a temporary cleanroom where the team could get to work. And even though there are people who have been working on this for something like 20 years, and I have not. I’m—like my involvement is so small—but I got goosebumps, I got chills just knowing that pieces of outer space were right there in front of me. It was such a special moment to be part of

 

Padi Boyd: And seeing it with your own eyes, right? Like,  you know that it’s doing okay, but just having that moment of visually confirming it.

 

Jacob Pinter: And like you were talking about earlier, being with a team who’s been working so hard to make it all possible, you really felt that camaraderie like yes, again, I didn’t have anything to do with this. I didn’t have anything to do with this. But I felt like, “Yeah, I did this.” I was part of this, you know?

 

Padi Boyd: It’s a moment for everyone, right?

 

Jacob Pinter: I can tell you about another episode that I’ve worked on that I’ve really enjoyed. And it was the focus of our season finale episode, which is called “A Year in Mars Dune Alpha”. So there are these four crew members. They’re living in a simulated Mars habitat here on Earth. And NASA researchers are collecting data, which will eventually inform how they’ll plan an eventual human mission to Mars—like, the real Mars, not a simulated habitat. So the crew is almost completely cut off from the outside world. But I was able to communicate with them by voice memo. So let’s take a listen.

 

[clip from “A Year in Mars Dune Alpha” episode]

 

Anca Selariu: Hello Earthlings. This is what Mars airlock sounds like.

 

Nate Jones: If I could sum up CHAPEA in just a couple of words, the words would be “almost Mars”.

 

Kelly Haston: People often ask what it smells like. It doesn’t actually have a lot of smell, and one of the reasons is that … [fades out]

 

Anca Selariu: You hear a constant hum. I like to imagine it as the engine of Mars.

 

Kelly Haston: Science is an iterative process. You iterate on things. You make small discoveries that build and build, and I think that this study is an example of that.

 

[end of episode clip]

 

Padi Boyd: Well, that is so cool. So did the voice memo process actually include like a delay, the same as you would have if you were talking to the folks on a Mars trip?

 

Jacob Pinter: It did. So we expect that when people eventually go to Mars, depending on where Mars is in relation to Earth, there’ll be something like 15 to 20 minutes that it’ll take a signal to go each way. So if you think about, if I’m on the crew on Mars, and you’re in mission control, and I need to call you, I send you a message. It takes 15 to 20 minutes to get there. You figure out what you’re going to say, and it takes another 15 to 20 minutes for me to get the answer. So the crew really has to be creative. They have to be problem solvers. And they also just have to exist in isolation with three other people and no sunlight and no fresh air for a year. And so for the researchers, keeping an eye on these four crew members, there’s a lot of valuable data that they can get from sort of how that all works and the impact it has on the crew members.

 

One other cool thing I want to spotlight is that we got to investigate the sounds of the sun. It’s in an episode called “Hum of the Sun”. And we explain how heliophysicists—or sun scientists— are finding a lot of value in listening to our star. So one of the researchers discovered that the sun creates these harmonic frequencies that sound musical. And Padi, we actually get to hear you sing a little bit in that episode. So let’s listen. Here’s what it sounded like.

 

[clip from “Hum of the Sun” episode]

 

Robert Alexander: 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 then the fifth. This creates these musical harmonic components in the solar wind.

 

When you listen closely to the audio you get this [hums] above the [hums again]. You hear that? And then depending on how much of the turbulent noise you filter out, you can hear the [hums along at higher pitch] higher order harmonics.

 

My mind was blown. Like, you can hear the harmonic series in solar data. It’s crazy!

 

Jacob Pinter: So Padi, when we—again, to peel back the curtain a little bit, listeners might not know that we basically surprised you with this and put you on the spot and played you this tape.

 

Padi Boyd: Yeah.

 

Jacob Pinter: And then you just reacted spontaneously. So I’m really I was in the room when that happened. We were blown away by how it sounded in the end. But I’m really curious for you when you heard that and sort of thought about what you could do with it, what was that like?

 

Padi Boyd: Well, I was so mind-blown by the concept of being able to listen for patterns, because we’ve been talking about looking for patterns. And now we’re talking about taking the same data, but just putting it in through a different part of your brain. How does that part of your brain find patterns? And so music is all about these harmonics, you know, how does like the fundamental and a third or a fifth relate to the whole sound. I was just really kind of moved and blown away by the fact that we could hear patterns that were telling us something about what was going on physically. But also, they sounded so beautiful, and that we could just connect them to something that we’re so familiar with. You know, music is very familiar to people, but it’s invisible, and it’s mysterious, and we can’t really measure the impact it has like on your soul, your feelings. So I just thought it was fantastic to think about how things sound.

 

Jacob Pinter: Here at Curious Universe, as you know, we love to nerd out about space and all kinds of science. And by now you have hopefully noticed that we also like to have fun while we do it. But I’ve got to tell you, it wouldn’t mean a thing if it weren’t for you, the listeners. We really appreciate you listening. And we always love to hear what you think of the show. If you need a new adventure, you can always find us at nasa.gov/curiousuniverse. There’s a backlog there of every episode we’ve released since 2020. And whether you’re a first time space explorer or a total space nerd, there’s definitely a Curious Universe episode for you.

 

[Theme song: Curiosity by SYSTEM Sounds]

 

All right, well, that’s a wrap for season six of NASA’s Curious Universe. Again, thank you so much for tuning in this season and for supporting the show.

 

Padi Boyd: It’s time for us to take a break and work on new episodes. But I promise we’ll be back soon with more adventures. Until then, you can find us any time at nasa.gov/curiousuniverse and find even more NASA podcasts in your favorite podcast app or at nasa.gov/podcasts.

 

Jacob Pinter: And remember, stay curious. And we’ll see you next time. Thanks.