I glow, therefore I am

Summary

Unexplainable – "I glow, therefore I am"

Release Date: April 27, 2026
Podcast Host: Vox
Key Hosts & Guests: Brian Resnick, Noam Hassenfeld, Amy Bedoola, Rodolfo Antonio Salido Benitez

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Episode Overview

In this episode, the Unexplainable team embarks on a "double feature" exploring two interwoven mysteries at the edge of biology:

1. The phenomenon of "biophotons"—the ultra-faint visible light emitted by all living things, potentially allowing scientists to distinguish life from death with sensitive cameras.
2. The secrets of the International Space Station (ISS) microbiome—how the intensely controlled, ultra-clean environment in space shapes the microscopic life astronauts live with, and what that reveals about health, sterility, and our relationship with microbes.

The tone is playful and curious, with the hosts riffing on pop culture (Barbenheimer!), contemplating the nature of life and death, and considering the surprising importance of microbial diversity both in space and here on Earth.

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Key Discussion Points & Insights

Part 1: What Makes Something Alive? We (Literally) Glow (01:15–14:14)

• What is the Difference Between Dead and Alive?

  • The episode begins with the classic philosophical question, then pivots to a recent discovery: "What if I were to tell you there was a way to tell whether anything is alive or dead...and all you need is a camera? A really sensitive camera." (Brian Resnick, 02:41)

• Biophotons: The Light of Life

  • Daniel O. Block, a quantum physicist at the University of Calgary, investigates "biophotons," faint visible photons emitted during the metabolic reactions of living cells—not heat (infrared) and not bioluminescence.
    • "It's just the light of life." (Brian, 04:18)
    • Every living thing—plants, animals, us—emits these.
    • The amount is infinitesimal: "We're talking about a few photons, like 10 photons." (Supporting Speaker, 06:07)

• Capturing the Glow: The Mouse Experiment

  • Block's team photographed a living mouse and, after euthanasia, the same mouse in a light-proof, temperature-controlled box.
    • The living mouse glows with a spectrum (blue, green, red); after death, the glow dissipates, and only faint, scattered dots remain.
    • "It just feels like it's a picture of life fading away. And it's just so stark...you can just say: life, not life." (Brian, 08:17)
    • When asked if this was a "picture of the soul," the scientist replies:
      • "It's just a chemical process...You take a glow stick. You know, it doesn't show that this glow stick has a soul." (Supporting Speaker, 09:26)

• Healing Light in Plants

  • The same process is observed in leaves: when a leaf is scraped, the injury site glows brighter, possibly due to increased metabolic activity as it heals.
    • "They're like firemen running to the fire and throwing buckets...throw this out, right? Yeah, something like that." (Supporting Speaker, 10:46)

• Possible Applications (and Early Days)

  • The technique is currently limited by the minuscule amount of light, but future applications may include:
    • Monitoring organ health for transplantation.
    • Early detection of dying tissue.
    • Tracking plant or crop health remotely.
  • "It's all just like a huge maybe possible down the line because this is so, so, so early." (Brian, 12:50)

• A Visceral Metaphor for Life

  • The hosts reflect on the beauty of knowing we're all—literally—faintly glowing, though not in any mystical or soulful way.
    • "It's just sort of beautiful to think about." (Noam, 13:20)
    • "It's nice that we all glow." (Brian, 13:21)

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Part 2: Microbial Life on the Space Station (15:52–25:25)

• Exploring Microbes in Space

  • Amy discusses a study on the ISS microbiome, with guest Rodolfo Antonio Salido Benitez (lead author):
    • Reasons for study: astronaut health and "spacecraft health" (microbes can form biofilms and damage hardware). (Amy & Rodolfo, 17:08–17:44)

• Life in a Microbial Bubble

  • Despite rigorous sterilization, antimicrobial wipes, air filters, and astronaut quarantine, the ISS is not germ-free but dominated almost entirely by human-derived microbes (skin, mouth, urine, feces).
    • “The ISS is essentially colonized by a lot of human related microbes.” (Amy, 19:20)
    • “Given the difficulty of bringing things into the ISS, its microbiome is very diminished. Very reduced in diversity compared to what we would see on the surface of the Earth.” (Rodolfo, 19:54)

• Why Microbial Diversity Might Matter

  • There's reason to think low microbial diversity could be bad for astronauts: the study references connections between a lack of microbial exposure and increased chronic inflammatory diseases, as well as astronauts' rashes and immune issues.
    • "Astronauts on the ISS often have rashes, allergies, immune function issues." (Amy, 21:12)
  • But the effects aren’t settled and some mouse studies challenge the idea that diversity always helps. (21:22–21:33)

• Broader Metaphor: Over-Sterilized Homes

  • The ISS is seen as an extreme version of the ultra-sterile, climate-controlled modern home—raising the question: are we making ourselves less healthy by being too clean?
    • Rodolfo’s previous research swabbed household surfaces, relating to “our nuclear warfare with dirty and grime in our houses,” examining how cleaning impacts our microbial landscape. (Rodolfo, 23:36)
    • "The ideal version of what we're striving for...that could actually be in some ways not great for us." (Amy, 24:02)
  • Takeaway: “A little bit of chaos goes a long way.” (Amy, 24:53)

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Notable Quotes & Moments (with Timestamps)

• "What would you say is the difference between something dead or alive?"

  • Brian Resnick, 02:10

• "Each of us is shining with like a mild aura of life that is not even metaphorical. That is literally true."

  • Brian, 05:03

• "I wish people could see this image...it looks like you have the shape of a mouse on the top glowing with light, and then on the bottom you have this mouse just kind of dissolving. It just feels like it's a picture of life fading away."

  • Brian, 08:17

• "Did you take a picture of the soul?" "No, this is just a chemical process."

  • Brian & Supporting Speaker, 09:00–09:26

• "It shows what's going on in the leaf metabolically...he wonders if there should be maybe some more research on how metabolic activity seems to sort of spread out from an injury site."

  • Brian, 10:52

• "It's nice that we all glow."

  • Brian, 13:21

• "Given the difficulty of bringing things into the ISS, its microbiome is very diminished. It's very reduced in diversity..."

  • Rodolfo, 19:54

• "The ISS feels like the most intense, the ideal version of what we're striving for...that could actually be in some ways not great for us."

  • Amy, 24:02

• "A little bit of chaos goes a long way."

  • Amy, 24:53

---

Key Timestamps

• 01:15 – Start of host discussion; intro to the double-feature structure.
• 02:41 – Introducing the question of how we distinguish life from death.
• 04:05 – Explanation of biophotons and Daniel O. Block’s research.
• 07:04 – Describing the mouse biophoton experiment setup and results.
• 09:00 – Reflection: is this imaging of the soul? No, just chemicals.
• 10:12 – Biophoton imagery in healing plant leaves.
• 12:49 – Discussing possible applications and current limitations.
• 13:20 – Hosts reflect on the beauty of the discovery.
• 15:52 – Second feature: microbial life on the ISS; introducing Rodolfo.
• 19:54 – Rodolfo explains the diminished microbial diversity in space.
• 21:12 – Linking low diversity to astronaut health issues.
• 23:36 – Comparing ISS cleaning to our own homes.
• 24:02 – Questioning the wisdom of ultra-clean indoors.
• 24:53 – Summing up: the value of “a little chaos”.
• 25:39 – Directions to see research images and further reading.

---

Further Reading & Related Resources

• Daniel O. Block’s paper on biophoton imaging (linked in show notes)
• Rodolfo Salido Benitez’s paper on the ISS microbiome (also linked)
• Rob Dunn’s book "Never Home Alone” – explores the unseen microbial residents of our homes

---

Summary

"I glow, therefore I am" takes listeners on a journey to the literal and metaphorical borders of life: how the faint light from every living cell might offer a new, physical way to observe the threshold between life and death—and how efforts to create sterile, "perfect" environments (in space or at home) may have unforeseen costs, cutting us off from the unseen web of life that helps keep us healthy. The episode is rich in curiosity, gentle awe, and scientific humility, reminding us that—even in the dark—living things have a light all their own.

Transcript

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[Host 1 (possibly Brian Resnick)]

Hello, Bird.

[Host 2 (possibly Noam)]

Hello, Noam.

[Host 1 (possibly Brian Resnick)]

How's it going?

[Host 3 (possibly Amy Bedoola)]

It's going great. I'm happy to see you.

[Host 1 (possibly Brian Resnick)]

Me too. So a while back, I came to you with this idea, or more like a question. Right. What's better than one unexplainable?

[Host 2 (possibly Noam)]

Nine unexplainables.

[Host 1 (possibly Brian Resnick)]

I was thinking more like two. I don't know. I think we do a little two in one. Maybe I tell you a little thing, you tell me a little thing, and we do a little double feature.

[Host 3 (possibly Amy Bedoola)]

I like double features.

[Host 1 (possibly Brian Resnick)]

Maybe we do like a Barbenheimer. One of us can be Barbie. One of us can be Oppenheimer.

[Host 2 (possibly Noam)]

Okay.

[Host 1 (possibly Brian Resnick)]

I don't know which of us will be which.

[Host 2 (possibly Noam)]

I'd like to be Barbie.

[Host 1 (possibly Brian Resnick)]

I think maybe we'll do the stories. We'll see who's who at the end, we'll check in.

[Host 2 (possibly Noam)]

Okay, that sounds good.

[Guest (Rodolfo Antonio Salido Benitez)]

Do you have yours?

[Host 1 (possibly Brian Resnick)]

Do you have your unexplainable nugget?

[Host 3 (possibly Amy Bedoola)]

I have my unexplainable. I am ready.

[Host 1 (possibly Brian Resnick)]

And we'll see who gets to be Barbie.

[Host 2 (possibly Noam)]

Great.

[Host 1 (possibly Brian Resnick)]

So I want to start with a question.

[Host 3 (possibly Amy Bedoola)]

Okay.

[Host 1 (possibly Brian Resnick)]

What would you say is the difference between something dead or alive?

[Host 3 (possibly Amy Bedoola)]

One's dead and the other's alive.

[Host 1 (possibly Brian Resnick)]

Good. Good analysis, Bird.

[Host 3 (possibly Amy Bedoola)]

But we did also, like, we did a whole episode about this that was sort of like, where is the line between life and death? You know, we had heart death. Then we created this definition of brain death as well. But that line is less obvious. Than I think it might initially appear.

[Host 1 (possibly Brian Resnick)]

Okay, so what if I were to tell you there was a way to tell whether anything is alive or dead? You know, even like a leaf. And all you need is a camera, Like a really sensitive camera.

[Host 2 (possibly Noam)]

Is this like vampires don't show up on cameras so you can like identify the undead? Like.

[Host 1 (possibly Brian Resnick)]

Oh, okay, that actually might be a better way of doing this than my idea.

[Host 3 (possibly Amy Bedoola)]

Okay.

[Host 1 (possibly Brian Resnick)]

But no, this comes from this guy, Daniel O. Block. He's a professor at the University of Calgary in Canada. He works on quantum physics. So you know the physics that happens at a subatomic level.

[Host 3 (possibly Amy Bedoola)]

Sure.

[Host 1 (possibly Brian Resnick)]

And he got really interested in looking into ways quantum physics might interact with biology. I don't know if you've heard of any of these possible ideas. There is a theory that the thing that explains how smell works is quantum physics.

[Host 3 (possibly Amy Bedoola)]

Uh huh.

[Host 1 (possibly Brian Resnick)]

There's this other idea that birds. The way that they can sense Earth's magnetic field and get around is by some kind of weird quantum effect in their eye.

[Host 3 (possibly Amy Bedoola)]

Sure.

[Host 1 (possibly Brian Resnick)]

So Daniel was looking into questions of quantum physics and biology, and a colleague told him about something called a biophoton.

[Host 3 (possibly Amy Bedoola)]

Sorry, photons are like the sort of particle form of light.

[Host 1 (possibly Brian Resnick)]

Yeah.

[Host 3 (possibly Amy Bedoola)]

But then we're saying biophoton, like alive

[Host 2 (possibly Noam)]

part of life, like a living.

[Host 1 (possibly Brian Resnick)]

Oh, no, no, no. The photon is not alive, but the photon is related to life. Okay, so it's a kind of light that all living things give off. It's not heat. You don't need a thermal camera or an infrared camera to see it. It's visible light. It's also not bioluminescence, which is another type of light I know you've done reporting on that has a particular molecular reaction that creates tons of light that you can see from far away. It's just the light of life.

[Host 3 (possibly Amy Bedoola)]

What? Wait, so, okay, to clarify, what you are supposedly telling me is that each

[Host 2 (possibly Noam)]

of us is shining with like a

[Host 1 (possibly Brian Resnick)]

mild or aura of life that is not even metaphorical. That is literally true.

[Host 2 (possibly Noam)]

Is it like a visible aura of life?

[Host 1 (possibly Brian Resnick)]

So it seems like all metabolic reactions create visible light. Every cell, you know, the smallest possible bit of what is alive as it is doing stuff, as it's making stuff, as it's just existing, it's giving off light, Like a teeny, teeny tiny amount of visible light. So Daniel told me, for a comparison,

[Supporting Speaker (possibly Rob Knight or another expert)]

if you were to turn on a light bulb, and the other day, I was just out of curiosity figuring out the number, it's something like 10 to the power. 18 photons, it's a billion Billion. That's how much light comes from a light bulb.

[Host 1 (possibly Brian Resnick)]

To guess how much we're talking here, how many photons metabolic reactions give off? Nine. Oh, my God, that is such a good guess here.

[Supporting Speaker (possibly Rob Knight or another expert)]

We're talking about a few photons, like 10 photons.

[Host 1 (possibly Brian Resnick)]

You have one photon off.

[Host 2 (possibly Noam)]

Never been wrong in my life.

[Host 1 (possibly Brian Resnick)]

Quintillions of photons. And you got one photon off.

[Host 2 (possibly Noam)]

Okay, great.

[Host 1 (possibly Brian Resnick)]

But you'd never be able to see my biophotons with the naked eye. So you need a really, really, really dark room and a really, really sensitive camera. And there have been examples of people that have looked for biophotons in living tissue before, but Daniel doesn't think anyone's ever looked at a full living organism until his team. Okay, now this is not the funnest part, but you know how lots of scientific experiments use mice that having to be euthanized? Yeah. So Daniel figured that if they were going to be euthanized at the end of an experiment anyway, they might as well do something positive with it.

[Host 3 (possibly Amy Bedoola)]

So a mouse died.

[Host 1 (possibly Brian Resnick)]

Yeah. So his team got a mouse before it died, put it in this super dark box, kept the temperature at a constant 98.6 degrees. So, you know, things get colder when they die. And they didn't want the heat to impact the image at all, so they kept it constant. And then they took a photo with this super sensitive camera in this really dark box. Then they euthanized the mouse and they took another photo. And I want to show you what they found. Here is a picture, and I just want you to tell me what you see.

[Host 3 (possibly Amy Bedoola)]

Okay. There is a picture of a live mouse and a picture of a dead mouse and the alive mouse. It looks almost like a brain scan in some ways. It's got like blue and green and red, and it's sort of the outline of it from above is illuminated in blue and green and red.

[Host 1 (possibly Brian Resnick)]

Yeah.

[Host 3 (possibly Amy Bedoola)]

And then if you go down to the deadmau 5, you can still sort of vaguely see the shape of it, but it's no longer filled in. It's like a pointillist, like little dots of blue.

[Host 1 (possibly Brian Resnick)]

Yeah.

[Host 3 (possibly Amy Bedoola)]

But other than that, it's. It's like it's disintegrating.

[Host 1 (possibly Brian Resnick)]

I wish people could see this image. We can link this in the show notes, but it's just nuts. Like it looks like you have the shape of a mouse on the top glowing with light, and then on the bottom you have this mouse just kind of dissolving. It just feels like it's a picture of life fading away. And it's just so stark. You know, there's all these processes associated with life, you know, like the heart, the brain. But you have this picture here where you can just say life, not life.

[Supporting Speaker (possibly Rob Knight or another expert)]

It's like a window into whether the being is alive or not.

[Host 1 (possibly Brian Resnick)]

I don't know if your brain goes here, but when I saw this picture of just sort of this weird glow of life disappearing, I was initially just like, daniel, did you take a picture of the soul? But he was just saying, like, no, this is just a chemical process. They're taking a picture of, you know, the end of all the processes of life. For this mouse.

[Supporting Speaker (possibly Rob Knight or another expert)]

You take a glow stick. You know, a glow stick is like two chemicals. You break it and they start emitting light. It's a chemical process that emits light. You know, it doesn't show that this glow stick has a soul.

[Host 3 (possibly Amy Bedoola)]

I don't know. Just looking at this, I think I'm still fundamentally hung up on the idea that we're all very, very faintly glowing.

[Host 1 (possibly Brian Resnick)]

And there's more to this that could be kind of more potentially useful. So he did this other experiment where he took a leaf and he did the same thing, put it in a dark, temperature controlled place, and then he made some tiny scrapes on it.

[Host 3 (possibly Amy Bedoola)]

Okay.

[Host 1 (possibly Brian Resnick)]

And I just want to show you what this looks like.

[Host 3 (possibly Amy Bedoola)]

Okay. So I'm looking at some leaves, and then there are these white streaks, like gashes across them.

[Host 1 (possibly Brian Resnick)]

Yeah. And that's where the leaves were scraped.

[Host 3 (possibly Amy Bedoola)]

Is it like the cells are trying to heal so they have more intense metabolic practices. So they're glowing more.

[Host 1 (possibly Brian Resnick)]

Yes. What Daniel says is he thinks this is showing the leaf trying to heal itself.

[Supporting Speaker (possibly Rob Knight or another expert)]

They're like firemen running to the fire and throwing buckets. Like, throw this out, right? Yeah, something like that.

[Guest (Rodolfo Antonio Salido Benitez)]

Wow.

[Host 1 (possibly Brian Resnick)]

It shows what's going on in the leaf metabolically. And he wonders if there should be maybe some more research on how metabolic activity seems to sort of spread out from an injury site.

[Host 3 (possibly Amy Bedoola)]

Well, it also makes sense in terms of when you look at. I mean, I know it's different. Cause when you look at an image of the brain, it's not literally being like your brain is glowing in this way. Right. But you. Yeah, when we look at an image of the brain, all the blood going to one part of the brain lights it up in that way. It looks very similar of like, oh, there's a lot of activity there. And so that's something that we've translated into light. But this is just like things are literally maybe glowing.

[Host 1 (possibly Brian Resnick)]

Yeah. There's a Lot of confounding factors. I think we're very far away from this research being particularly useful. He did this analysis recently showing that it would be pretty hard to get any useful biophoton information on a brain without going, like, inside the skull, just because of all the other biophotons coming from the skin and stuff. We're still very, very early days in this research. The photons coming out of this stuff is just so, so, so, so slight. Daniel said that they weren't even planning to release anything about this mouse until they saw the picture. And they were just like, oh, my God, this is so stark. Like, this mouse is dissolving. We have to just put this out. But he does think that eventually this type of thing could potentially be useful for a couple of things. So, like organ transportation. If you're transporting organs for transplants, it could potentially be a way of a sort of early diagnostic if one of the organs is not living or having trouble. There's this other potentially cool idea where it could be useful for monitoring crop health and forest health. Like, maybe there's a way to monitor the health of a plant population just by looking at the glow coming off of it.

[Host 3 (possibly Amy Bedoola)]

Hmm.

[Host 1 (possibly Brian Resnick)]

It's all just like a huge maybe possible down the line because this is so, so, so early. But I don't know. Just for me, even though we're so early, the idea that light, like just regular visible light, can tell the difference between something that is alive and dead. Like, to me, it feels like we're scratching the surface of something really big here.

[Host 3 (possibly Amy Bedoola)]

Yeah.

[Host 1 (possibly Brian Resnick)]

And there's so many places for this to go. That gets me just really, really excited.

[Host 3 (possibly Amy Bedoola)]

It's just sort of

[Host 2 (possibly Noam)]

beautiful to think about.

[Host 1 (possibly Brian Resnick)]

Yeah. Like, whether it's the soul or just kind of. It's nice that we all glow.

[Host 3 (possibly Amy Bedoola)]

I don't think it's the soul.

[Host 1 (possibly Brian Resnick)]

No, it's not the soul. Okay. That's my half of the double feature. I think I'm Barbie because it's like, Barbie's a doll, you know, she has a life force, if you believe. But I don't think she's emitting biophot, so I think I'm Barbie. I don't know if you're Oppenheimer.

[Host 3 (possibly Amy Bedoola)]

I kind of want to also be Barbie.

[Host 2 (possibly Noam)]

Being Barbie is so much more fun. If I'm Oppenheimer, I'm the end of the world.

[Host 1 (possibly Brian Resnick)]

We're doing Barbenheimers. I don't think we can both be Barbie.

[Host 2 (possibly Noam)]

We go to the movies, we watch Barbie again.

[Host 1 (possibly Brian Resnick)]

That's true.

[Host 2 (possibly Noam)]

Great. After the break. We maybe watch Barbie again? We'll find out.

[Host 1 (possibly Brian Resnick)]

Let's do it,

[Host 3 (possibly Amy Bedoola)]

Girl.

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[Host 3 (possibly Amy Bedoola)]

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[Host 1 (possibly Brian Resnick)]

And now I am become death

[Guest (Rodolfo Antonio Salido Benitez)]

Destroyer.

[Host 3 (possibly Amy Bedoola)]

So last year I was kind of poking around on questions of human health and space. And just because we care about human health, we care about space here on the show. Looking for papers.

[Host 1 (possibly Brian Resnick)]

I mean, you don't care about space

[Host 3 (possibly Amy Bedoola)]

on this is true. I care more about the ocean. But nevertheless, I was looking for human health and space papers and I saw this paper in the journal cell that I actually. Sorry, I just want to say I do care about space.

[Host 2 (possibly Noam)]

I've been following the Artemis 2 stuff closely.

[Host 3 (possibly Amy Bedoola)]

I care.

[Host 1 (possibly Brian Resnick)]

You just really care about the oceans.

[Host 2 (possibly Noam)]

I also really care about the oceans.

[Host 1 (possibly Brian Resnick)]

Someday we're going to have a space versus ocean.

[Host 3 (possibly Amy Bedoola)]

Someday we're going to have a space versus oceans battle. But today is not that day because I saw a paper and that was basically like we studied the microbes on the space station, the International Space Station. And as you know, I'm obsessed with microbes. Obviously reached out to the lead author on this paper. Very fun individual.

[Guest (Rodolfo Antonio Salido Benitez)]

My name is Rodolfo Antonio Salido Benitez. If you want to go the full name because we like to make it sound like we're not telenovela and so

[Host 3 (possibly Amy Bedoola)]

I asked Rodolfo basically why they wanted to study microbes on the International Space Station. And he told me like this study was not new, right? There have been several studies of ISS microbes and there are kind of a few reasons to do this. So one, they just sort of want to know what the astronauts up there are being exposed to, like what is up there around them, how it might be affecting them. And then two, which I just hadn't thought as much about was spacecraft health.

[Guest (Rodolfo Antonio Salido Benitez)]

What.

[Host 3 (possibly Amy Bedoola)]

So he was saying that like microbes can form biofilms that could mess up your hardware potentially.

[Host 1 (possibly Brian Resnick)]

Oh, like the health of the spacecraft stuff.

[Host 3 (possibly Amy Bedoola)]

And then I had read previously this isn't a microbe, but Mir M I R the sort of like Russian space station had issues with fungus at one point. So it is actually important to like monitor this stuff. And so Rodolfo himself does not go up in space, unfortunately. But this astronaut microbiologist named Kate Rubins, she went up to the International Space Station and she basically swabbed everything. So like food storage areas, exercise areas, personal hygiene areas, where they brush their teeth and then.

[Host 1 (possibly Brian Resnick)]

That is incredible.

[Host 3 (possibly Amy Bedoola)]

I didn't realize this, but they have to wipe, bathe, like they don't. They can't take a shower because the

[Host 2 (possibly Noam)]

water would, I mean, that would be crazy, go everywhere.

[Host 3 (possibly Amy Bedoola)]

But I wasn't, I was.

[Host 1 (possibly Brian Resnick)]

No, I don't really spend time like imagining astronauts showering. I haven't really thought about that, honestly.

[Host 3 (possibly Amy Bedoola)]

So they're swabbing all of this, all these areas and then they bring all this back to analyze and they sort of confirmed what other studies had found on the iss, which is they have really careful sterilization procedures up there, right? They have air filters. Astronauts are not just wiping down themselves, they're also wiping down everything with these like antimicrobial wipes. They have vacuums, quarantines before they go up. But that does not mean that the ISS is like germ free. Right. Instead, the ISS is essentially colonized by a lot of human related microbes. So microbes from human bodies, so from

[Host 2 (possibly Noam)]

skin, from mouths, from urine and feces, like everywhere.

[Host 3 (possibly Amy Bedoola)]

Which to be clear, is also true of like, you're in my house, right? There would also be microbes from our mouths.

[Host 1 (possibly Brian Resnick)]

Yeah, don't hate on the space station,

[Host 2 (possibly Noam)]

there are microbes from our mouths in

[Host 3 (possibly Amy Bedoola)]

the room right now. But comparatively, Rodolfo said our homes are just a lot more sort of diverse. Our microbial environment is more diverse because we're bringing in more stuff in indoor homes.

[Guest (Rodolfo Antonio Salido Benitez)]

You might introduce new bacteria simply by opening the window or by tracking bacteria in your shoes or in your backpack as you lay it out in the outside environment and then bring it in. Given the difficulty of bringing things into the iss, its microbiome is very diminished. It's very reduced in diversity compared to what we would see on the surface of the Earth.

[Host 1 (possibly Brian Resnick)]

Is there a way that having more microbes is better or worse for us or the house?

[Host 3 (possibly Amy Bedoola)]

So that's literally the question that Rodolpho is trying to answer. They want to know sort of are humans actually better off with a richer, more varied landscape of microbes around us? And we don't have all the answers to this. In the paper in the journal Cell, they say sort of figuring this out is an important long term goal. Basically they link to a bunch of studies that sort of connect being less exposed to microbes to chronic inflammatory diseases. They say astronauts on the ISS often have like, rashes, allergies, immune function issues.

[Host 1 (possibly Brian Resnick)]

I imagine it's not the same thing, but it sort of feels reminiscent of this idea that if you're in sort of a hermetically sealed place and you're not getting exposed to stuff and developing immune reactions and all that, it could be bad for you.

[Host 3 (possibly Amy Bedoola)]

Yeah, there's also, they talk about, like, there's evidence from mouse models that maybe being exposed to a diversity of microbes doesn't always help. So like, it's Right.

[Host 1 (possibly Brian Resnick)]

Okay.

[Host 3 (possibly Amy Bedoola)]

I don't think that it's totally clear.

[Host 1 (possibly Brian Resnick)]

There's also like a lot of other stuff going on in the space station.

[Host 3 (possibly Amy Bedoola)]

Right, exactly.

[Host 2 (possibly Noam)]

Like you're, they're being exposed to all

[Host 3 (possibly Amy Bedoola)]

sorts of things and they're in.

[Host 1 (possibly Brian Resnick)]

The radiation is like pummeling them in the face.

[Host 3 (possibly Amy Bedoola)]

And also just like being trapped in

[Host 2 (possibly Noam)]

a room with only a few people for a long time.

[Host 1 (possibly Brian Resnick)]

Like, yeah, not great.

[Host 3 (possibly Amy Bedoola)]

So researchers just want to know more about how this sort of impoverished microbial community affects astronauts. And also if there's a way to make life in space on a place like the ISS or any future sort of home for humans more like Earth. Like, do we need to figuratively track in dirt in some way?

[Host 1 (possibly Brian Resnick)]

What does this all do for the actual space station? Like, I don't know, is it different? Does it smell different in any way?

[Host 3 (possibly Amy Bedoola)]

So there's a scientist that I spoke to years ago, this guy named Rob Dunn, and when we were speaking, we were talking about the fight less with microbes in our homes and more with like bugs, like insects and like things you can see. Right, things you can see or sometimes not, but like the insects and spiders and whatever in our home mites, et cetera. But he wrote this book called Never Home Alone, where he actually does mention microbes and the ISS as well. And in that book he suggested that the ISS smells of body odor, which I guess would make sense to me because it's full of small enclosed space bacteria. But I think sort of the most interesting thing to me is that Rodolfo is essentially saying to me that to him the ISS is kind of like an extreme version of what we almost strive for when we live indoors. Like, yes, our homes are definitely, they're more microbially diverse than the space station. But he actually got into all this because he was part of another study looking into people's homes and their cleaning habits in their homes.

[Guest (Rodolfo Antonio Salido Benitez)]

Part of this interrogation also involved swabbing surfaces to try to see how our nuclear warfare with dirty and grime in our houses could also be having impact on our microbial landscape and the types of microbes that we interact with.

[Host 3 (possibly Amy Bedoola)]

And to me, like, the ISS feels like the most intense, like the ideal version of what we're striving for, right?

[Host 2 (possibly Noam)]

Like literally nothing can get in unless

[Host 3 (possibly Amy Bedoola)]

we add it in. And the idea that that sort of perfect version of like a cleaner's paradise of nothing is gonna get in, we can eliminate everything could actually be in some ways not great for us, like the opposite of what we need. I don't know. I'm certainly not gonna stop like disinfecting stuff, but I am gonna, I guess, like throw open the windows a bit and just sort of celebrate my outdoor germs to a certain extent.

[Host 1 (possibly Brian Resnick)]

It's a nice metaphor for how maybe we should live our lives. You know, don't clean everything out. Some mess is good. Keep some microbes.

[Host 3 (possibly Amy Bedoola)]

A little bit of chaos goes a long way.

[Host 1 (possibly Brian Resnick)]

I gotta say, Bird, based on how Rodolfo is talking about this like a nuclear bomb, I feel like you are Oppenheimer.

[Host 3 (possibly Amy Bedoola)]

I just, I wanted to be Ken.

[Host 1 (possibly Brian Resnick)]

There's no Ken. I'm Barbie. You are Oppenheimer.

[Host 2 (possibly Noam)]

I have to invent the nuclear bomb.

[Host 3 (possibly Amy Bedoola)]

I'm just kidding.

[Host 1 (possibly Brian Resnick)]

Well, thank you. Thanks for double featuring with me.

[Host 3 (possibly Amy Bedoola)]

Yeah, let's double feature again, I guess.

[Host 1 (possibly Brian Resnick)]

Sorry. You could be part of me next time.

[Host 3 (possibly Amy Bedoola)]

If you would like to see the biophoton images, we will link to Daniel's paper in the show description. We will also link to Rodolfo's paper about the iss. And if you want to read more about microbial environments and what it means to over clean our homes of bugs, both big and small. I really recommend Rob Dunn's book. It's called Never Home Alone. This episode was edited by Joanna Solotarov and produced by the wonderful Amy Bedoola. Amy, we are so grateful to you for everything you've done for the show and we couldn't have asked for a better fill in host. So thank you. Noam helped the production of this episode and also did the music. Christian Ayala did the mixing and the sound design. Melissa Hirsch checked our facts and Sally Helm and Meredith Hodnot for the fact that Mera is back from leave and we are so happy to have her. Thanks always to Brian Resnik for co creating the show with me and Noam. And a big thanks to Rob Knight for walking me through some facts about the ISS paper as well. If you have thoughts about the soul, or about cleaning your house, or about pretty much anything, please email us. We're@ unexplainableox.com if you'd like to support the show. The journalism of Vox does. We would love it if you would become a member. It's very easy to do, just go to Vox.com members. You will get access to all of Vox's journalism, but you'll also know that you are supporting Vox's journalism. And for those of you who have emailed us to let us know that you signed up because of Unexplainable, thank you. Thank you. Also to those of you who left us at Nice Review on your podcast platform or just told someone in your life about the show, you are all the best. Unexplainable is part of the Vox Media Podcast network and we will be back very soon with another episode about everything that we don't yet know.

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[Host 1 (possibly Brian Resnick)]

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