StarTalk Radio
Episode: Sounds of the Cosmos with Kim Arcand
Host: Neil deGrasse Tyson
Guest: Kim Arcand (Visualization Scientist & Emerging Tech Lead, Chandra X-Ray Observatory)
Co-Host: Chuck Nice
Date: November 25, 2025
Overview
This episode dives into the science, art, and unexpected creativity behind "data sonification"—the process of translating astronomical data (especially from invisible wavelengths like X-rays) into sound—led by guest Kim Arcand, a pioneer in the field and a visualization scientist at the Chandra X-Ray Observatory (a NASA mission operated by the Smithsonian). Through listener-submitted Cosmic Queries, Kim, Neil, and Chuck explore the purpose, methods, scientific insights, and playful joy of making the cosmos audible, as well as the broader mission of making space science accessible to all.
Key Discussion Points & Insights
1. What is Data Sonification?
[03:28]
- Kim Arcand: Data sonification translates complex cosmic phenomena into sound for both scientific analysis and public engagement.
- “My whole job is just about thinking about our data differently and figuring out other ways that we can visualize it, translate it into sound, which is sonification, bring [it] into tactile or...haptification types of environments...just trying to really dig down into how we represent our data, whether for scientific analysis or for communication and public engagement, both of which are...worthwhile things to do.”
- Useful for both sighted and blind/low vision scientists.
- Mixing senses can reveal hidden patterns and reinvigorate familiar datasets.
- “When introducing new senses...it can just rewire your brain a little bit different...it can kind of open a new window.” [Kim, 04:10]
2. Inclusivity and Accessibility
[04:16 – 05:50]
- The Chandra team collaborates closely with blind and low-vision communities.
- All astronomical imagery is technically a translation, as much of the universe is invisible to human eyes (e.g., X-rays, infrared).
- Making data multimodal has widespread benefits—like the “cut curb effect”; what helps one group often helps all.
3. Science, Art, and Creativity
[08:08]
- Sonifications stimulate new scientific thinking and artistry.
- Kim describes an artist reconstructing visual images from sound, leading to new interpretations:
- “To take the sound that was produced with that data, but then to...backstep it until they had an image...I just...love those kind of ideas of just play and creativity, which seem like they would be bad words in the workspace, right? They're really not.” [Kim, 08:10]
4. Clarifying Radio, Sound, and Pop Culture Myths
[08:50 – 10:35]
- Neil addresses the misconception (fortified by movies like Contact) that "radio" waves are inherently sound.
- “Radio waves is electromagnetic energy...they were sending us radio waves that we converted to sound.” [Neil, 09:52]
- Kim notes similar misconceptions: neither space images nor “space recordings” are direct captures—they represent translations.
5. The Science and Engineering of Chandra X-Ray Observatory
[10:35 – 13:23]
- Chandra has the sharpest X-ray vision, acting as the "X-ray microscope of the universe."
- “Chandra has such exquisite resolution...half of an arc second...equivalent of if you're looking at a dime from a few miles away.” [Kim, 11:00]
- Specially engineered with barrel-shaped, nested mirrors to detect X-rays via “grazing incidence,” akin to skipping stones.
- “Normal mirrors don’t work...it’s like skipping a rock across a pond.” [Kim/Neil, 12:55]
6. Chandra’s Cosmic Discoveries
Black Holes & Pulsars
- Chandra excels at finding black holes by seeing X-ray bursts from matter spiraling in.
- Long-term observation allows tracking black hole "snacks" and outbursts.
- Pulsars (“zombie stars”) spin rapidly post-supernova, perfect for X-ray detection.
Technicolor Universe Analogy
- “Chandra and other telescopes across wavelengths are like providing us that gorgeous Technicolor experience that we didn’t have access to 20, 30 years ago.” [Kim, 20:37]
- Neil: “I first saw Wizard of Oz on a black-and-white TV, so...I had no idea anything different happened when she stepped through the door.” [21:15]
Eta Carinae & 3D Models
[22:01–25:15]
- Chandra’s studies of the Eta Carina region highlight ongoing star formation, eruptions, and material ejection ("space croissant" analogy).
- 3D models derived from data are 3D-printable and tactile.
- “These are actually done for scientific analysis. And then we're able to 3D print them so that scientists can study them...” [Kim, 24:46]
Notable Quotes & Memorable Moments
- “You know she puts the pressure on us now. A five-timer.” – Neil, on Kim’s return, [02:44]
- “Radio waves...are electromagnetic energy, not sound. So it makes people think that the aliens were sending us sounds, but they were not.” – Neil, [09:52]
- “Chandra is really a black hole hunter.” – Kim, [13:51]
- “It’s like Dorothy stepping out of black and white into a Technicolor universe.” – Kim, [20:37]
- “Did she just say space croissant?” – Neil, [24:42], after Kim likens a nebula structure to a giant cosmic pastry
- “All instruments welcome, including voices.” – Kim, on choosing musical instruments for sonification, [29:25]
- “Chandra's [sonifications] help us pick out patterns in data that can be hard to see. So...especially helpful in studying gravitational waves, variable stars—anywhere there’s rhythmic flickering.” – Kim, [26:36]
Listener Q&A Highlights
Q1: How does sonification help uncover new phenomena?
[26:21]
- Kim: Sonification can reveal patterns (like ripples in black hole data) missed visually or numerically. Parsing data over time (via sound) gives “the gift of time” for pattern recognition.
- “When you're listening to it, your brain responds in a different way because you’re getting that data parsed out to you...that’s an exciting space to do more experimenting.” [Kim, 28:03]
Q2: Musical Instrument Choices for Sonification
[28:42–29:34]
- Sonifications can assign different instruments (even voices, oboes, didgeridoo) to highlight different features in astronomical data.
Q3: Sonification and Accessibility
[04:30, 24:46]
- Visualizations and 3D models are made tactile for blind/low-vision users and anyone who learns “tactilely.”
Q4: Book Announcement—Why Space Will Freak You Out
[29:46–31:01]
- Kim discusses her new family-reader book, co-authored with Megan Watsky, focusing on weird, extreme, and “freaky” astronomical phenomena (e.g., glass-raining exoplanets, lava worlds, “zombie stars”).
Q5: Choosing Colors and Sounds in Data Representation
[41:21–47:15]
- Standard: Chandra usually maps low/mid/high energy X-rays to RGB (red/green/blue).
- Color/sonification schemes are chosen for clarity, aesthetics, and sometimes modified for scientific storytelling.
- Bullet Cluster case: Changed colors to improve public understanding of dark matter mapping.
- “We do have a kind of standardization, but the science drives the story, the science drives the visual, and then we adapt based on the needs…” [Kim, 45:54]
Q6: Surprising Insights from Visualization
[58:01–59:47]
- 3D modeling of supernova remnants (Cassiopeia A) revealed internal asymmetries and evidence that such an explosion could turn a star "inside out"—insights hard to glean from images alone.
Q7: Future Uses for VR/AR Visualization
[60:28–62:22]
- Astronauts already train for missions with VR; similar tools could be applied to astrophysical phenomena for research and outreach.
- Pokémon Go as a powerful, real-world example of how augmented reality gets people engaging with data.
Q8: If You Could Sonify Any Event...
[55:59–57:27]
- Kim dreams of sonifying time-domain changes—events that evolve detectably over weeks/months/years, like supernovae or gamma-ray bursts.
Q9: Can We Ever Point a Telescope at "Nothing"?
[68:42–70:47]
- Both agree: Every new observational technology reveals something new, no matter where it points. The limitation is technological, not cosmic emptiness.
Fun & Playful Banter
- “Only Neil can make an orbit sound like sex, you know?” – Chuck, [35:11]
- “Did she just say space croissant?” “I know, and I’m so hungry right now.” – Neil & Chuck, [24:42–24:44]
- Chuck’s recurring comic riff about ringtones, Pokémon Go, and black hole “voices.”
Recommended Resources & Further Exploration
- Explore Chandra sonifications, 3D models, and tactile resources: Chandra.si.edu
- Look up "Cassiopeia A" 3D models and deep field sonifications for download and experimentation.
- Kim Arcand’s new book for families: Why Space Will Freak You Out (details on Chandra/NASA pages)
Useful Timestamps
- Data Sonification Introduction: 03:28
- Inclusivity & Multimodal Data: 04:16–05:50
- Chandra X-Ray Engineering: 10:35–13:23
- Technicolor Universe/Analogy: 20:37
- Listener Q&A (Cosmic Queries): 25:15–end
- Color/Sound Choices in Visualization: 41:21–47:15
- Surprising Scientific Results from Visualizations: 58:01
- Future of VR/Astronaut Training: 60:28
- What Happens if You Point a Telescope at “Nothing”?: 68:42–70:47
Closing Thought
Neil deGrasse Tyson:
“If you have a telescope that’s opened a new window to the universe...it’s gonna make a discovery.” [70:19]
Kim Arcand:
“Every time we launch these new telescopes, we’re finding things deeper, further back. It really is a limit of our technological achievements.” [70:19]
As always: Keep looking up!