Why is Afghanistan so vulnerable to earthquakes?

Summary

Science In Action (BBC World Service)

Episode: Why is Afghanistan so vulnerable to Earthquakes?
Date: September 4, 2025
Host: Roland Pease

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Episode Overview

This episode dives into the devastating earthquake that struck Eastern Afghanistan, exploring the scientific reasons behind the country’s high vulnerability to seismic events. The show features expert analysis from Afghan seismologist Zakhary Shizai, insight on recent challenges in climate science communication with Andrew Destler, a report on landmark mouse brain research from Anne Churchland, and updates on the unusual interstellar comet 3I ATLAS with Daryl Seligman. The episode is rich with first-hand commentary, scientific nuance, and reflections on how science translates into real-world understanding and policy.

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Earthquake in Eastern Afghanistan: Why So Deadly?

(Main segment starts at 02:40)

Key Insights and Discussion Points

• Earthquake Details and Impact

  • A magnitude 6 earthquake struck just north of Jalalabad, Afghanistan, causing over 1,400 deaths. Despite its moderate size, the event was devastating.
  • Zakhary Shizai, Afghan seismologist at Oxford University, explains that housing construction and geography are major factors in the destruction.

• Geographical and Infrastructural Vulnerabilities

  • Many villages are built on steep slopes; houses are densely stacked, often “on top of each other” in mountainous areas.

    “Even in 1km square. There are thousands of houses in this village…some of the village are like very old, like from 2, 3, 400 years.”
    — Zakhary Shizai (03:16)

  • Accessibility is limited: remote, steep valleys make rescue and aid difficult.

• Seismic Activity and Shallow Quakes

  • Afghanistan has a complex network of active faults, especially near the Indian and Asian plate boundary. The most destructive earthquakes are shallow, allowing energy to reach the surface rapidly.

    “The shallow earthquakes can cause very damage and destruction in that area. And because the energy that released during the earthquake can come very quickly to the surface…”
    — Zakhary Shizai (05:20)

  • Shallow earthquakes (depths <10 km) are most dangerous, as shown in this event.

• Lack of Preparation and Awareness

  • Few seismic stations in the country (only four, two in Kabul), making monitoring and mapping difficult.
  • Public awareness about earthquake risk is very low; many residents do not understand seismic origins or risks.

    “There is no public awareness in the country…many people, they don’t believe these earthquakes [are] caused by tectonic plates or active faults.”
    — Zakhary Shizai (06:39)

• Call for Better Mapping and Education

  • Urgent need for high-resolution satellite mapping to understand fault lines and for public education to prepare communities for natural hazards.
  • Shizai aims to return soon to map the earthquake and collect crucial geological evidence.

Notable Quotes

• “The main causes [for the destruction] was that [the earthquake] was really shallow and close to the surface because of that, that caused very huge damage.”
  — Zakhary Shizai (05:53)
• “The most important thing is the public awareness to people and to understand this is like natural phenomena can cause casualty and destruction. We have to prepare against this kind of nature events.”
  — Zakhary Shizai (06:55)
• “They don’t have like knowledge. You know, they are poor people even there is like very limited education. They don’t have access to the technology. They will believe what they are hearing.”
  — Zakhary Shizai (07:24)

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Climate Science Under Siege: The US DOE Report Controversy

(Segment starts at 08:58)

Key Insights and Discussion Points

• US Department of Energy Report Sparks Outcry

  • A 2025 report commissioned by the US Department of Energy suggested global warming’s economic damages are overstated and that aggressive mitigation might be economically harmful.
  • 85 climate scientists, led by Andrew Destler (Texas A&M), responded with a 400-page rebuttal, cataloging scientific inaccuracies and misleading interpretations.

• Critical Rebuttal Highlights

  • The DOE Report is accused of cherry-picking studies, omitting key caveats, and misrepresenting consensus climate findings.

    “The report is built on simple misunderstandings of the scientific literature, selective citation…misquoting studies…That’s how you get to the conclusion that climate change is not a threat to human welfare.”
    — Andrew Destler (08:58)

  • Claims such as “CO2 enhances plant growth” are criticized for being simplistic and ignoring broader impacts on food security.

    “If somebody’s drowning and you’re screaming at them, ‘You need water to survive,’ that’s not a very helpful or accurate characterization of the situation.”
    — Andrew Destler (10:55)

  • Misuse of the 1930s Dust Bowl as evidence that climate extremes are not worsening is refuted; the causes of past and present heatwaves differ fundamentally.

• Broader Context for Science Communication

  • Destler underscores the dangers when political motivations override established science.

    “Climate science is probably the most scrutinized and reproduced science in the history of science.”
    — Andrew Destler (09:41)

  • The issue is seen as pivotal for US economic competitiveness and leadership in clean energy sectors.

    “When people look back in a century and the US is a second-rate economy and they say what happened, they might look at 2025 and say that was the year that we basically gave up competing on the technologies of the future.”
    — Andrew Destler (15:17)

Notable Quotes

• “Climate change doesn’t listen to reports, it listens to the rules of physics.”
  — Andrew Destler (14:51)
• “It really seems to me that they are working backwards. They know the answer they want to get and they just work backwards from it and they’re not trying to get to the right answer.”
  — Andrew Destler (13:36)

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Big Data, Big Brains: Mouse Decision-Making Mapped

(Segment starts at 17:02)

Key Insights and Discussion Points

• Landmark Brain Mapping

  • Anne Churchland of UCLA discusses how new “Neuropixels” probes allowed her team to record from hundreds of thousands of neurons across the entire mouse brain during decision making tasks.

    “Because of a new instrument that we used…we were able to generate a data set that’s a really large scale…”
    — Anne Churchland (17:38)

• Multi-region Decision Processing

  • Contrary to previous assumptions that decision-making involves only a few brain areas, signatures of this process were found across numerous, sometimes unexpected, regions—including deep structures.

    “We saw signatures of the decision making process in many, many, many structures…even some areas much deeper in the brain that weren’t even on our radar at all.”
    — Anne Churchland (20:08)

• Complexity of Animal Choices

  • Mice combined sensory evidence and prior beliefs when performing tasks, demonstrating sophisticated calculations analogous to those in humans.

    “They’re able to dial up and down the way that they combine priors and sensory evidence based on the quality of the evidence…”
    — Anne Churchland (21:31)

• Relevance for Human and Clinical Research

  • The approach offers templates for studying how genetics and aging affect brain-wide activity and has implications for research into autism and neurological disorders.

    “My hope is that this work will have tremendous relevance to human health one day down the line.”
    — Anne Churchland (23:41)

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Interstellar Visitor: Comet 3I ATLAS

(Segment starts at 23:51)

Key Insights and Discussion Points

• Discovery and Uniqueness

  • 3I ATLAS is only the third identified interstellar object to visit the solar system, first detected July 2025 by the ATLAS telescope in Chile.
  • With a perihelion on the far side of the Sun, observations must focus on its approach; the urgency is real given limited visibility.

    “As a comet gets closer to the sun…the amount of sunlight it receives increases. You can have lots of funny stuff happening, like different ices starting to sublimate, different jets turn on…”
    — Daryl Seligman (24:48)

• Strange Composition

  • The comet’s tail consists mainly of CO₂—unusual compared to typical Solar System comets, indicating formation in extremely cold, distant regions around its (unknown) parent star.

    “We have now seen water, but it looks like the tail is mainly carbon dioxide. And that is not what you typically see in a solar system comet.”
    — Daryl Seligman (26:55)

• Scientific Opportunities—and Frustrations

  • The opportunity to study such a pristine interstellar object is rare. While ground-based and space telescopes are mobilized, a true “close-up” mission would likely have required years of advanced planning.

    “In some crazy world we could [send a mission]….But it’s a harder sell to get [a spacecraft to] abandon everything it’s doing and go visit 3 Atlas.”
    — Daryl Seligman (29:57)

  • The next generation Rubin Observatory in Chile will aid in discovering more interstellar objects and, possibly, mounting future intercept missions.

Notable Quotes

• “There is a huge amount that we could learn about planet formation throughout the galaxy by looking up close at…an interstellar comet from another planetary system.”
  — Daryl Seligman (26:22)
• “We gotta take what we’re given. Right.”
  — Daryl Seligman (28:22)

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Timestamps for Key Segments

• Opening and Episode Preview: 01:48
• Afghanistan Earthquake Analysis (Zakhary Shizai): 02:40–07:35
• US DOE Climate Report and Rebuttal (Andrew Destler): 08:58–15:43
• Mouse Brain Decision-Making Advances (Anne Churchland): 17:02–23:51
• Interstellar Comet 3I ATLAS (Daryl Seligman): 23:51–31:17

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Memorable Moments & Tone

• The frank concern from Afghan seismologist Zakhary Shizai about the disconnect between scientific knowledge and local public perception.
• Andrew Destler’s frustration and passion about defending scientific integrity and its societal impact.
• Anne Churchland marveling at the unexpected complexity uncovered in the brain’s processing of decisions.
• Daryl Seligman’s enthusiasm—and wistfulness—about the fleeting opportunity science has to study an interstellar visitor in real time.

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By weaving timely disaster analysis with critical issues in climate policy, cutting-edge neuroscience, and interstellar mysteries, this episode demonstrates both the scope and subtlety of modern science—as well as the importance of public understanding and engagement.

Transcript

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[Roland Pease]

Welcome to Science in Action from the BBC World Service with me, Roland Peace. This week, a response from 85 climate scientists to an official US report that downplays the dangers of global warming.

[Andrew Destler]

I think inadequate is an understatement. I felt the report was a mockery of science, and I realized that everybody in the field felt this way. Basically, that's where the report came from.

[Roland Pease]

We catch up with what's been learned about interstellar comet 3I ATLAS since it was discovered racing into the solar system two months ago, and the closest ever look at what goes on inside a brain in action. A mouse's brain.

[Anne Churchland]

It used to be that electrophysiologists would record small numbers of neurons. Maybe they'd measure activity from 20 or 30, 30 or 100 neurons. But because of a new instrument that we used, we were able to generate a data set that's a really large scale.

[Roland Pease]

The week started with the terrible earthquake in east Afghanistan, just north of the city of Jalalabad. As of this recording, the death toll is over 1400, although the event measured only magnitude 6. Zakhary Shizai is an Afghan seismologist based at Oxford University. He was on the program after a sequence of quakes in the western end of the country in 2023. And he closely studied the web of fault lines where this week's event happened. And he's long warned of the vulnerability of villages there to even moderate shaking. As we saw on Monday, it was.

[Zakhary Shizai]

Not that much strong, but one of the most biggest factories here, like, was the flooding that already affected the area. And the second factor that caused much destruction was most of the houses are built in steep slope. And also the houses are built on top of each other, like on top of each other. Even in 1km square. There are thousands of houses in this village. As far as I know, some of the village are like very old, like from 2, 3, 400 years.

[Roland Pease]

I mean, you published a paper last year which I was looking at on the vulnerability of people in this area. And these, when you say steep slopes, these houses look almost like they're built into the edge of the mountain. The slopes are so steep.

[Zakhary Shizai]

Yes, exactly. Almost 70% or more than 70% of the terrain of the country is mountainous. I think there is not that much like very flat area like they built houses. This area is like some villages. Right now, there is no, like accessibility to some village. And they are very far away on very deep valleys and the slope is really steep. Flooding and steep slope landslide. These all factors come together and cause very high damage and casualties.

[Roland Pease]

I mean, this was a magnitude 6, which in my experience is not terribly strong, like you say, but it was very shallow. Was the shaking from it strong?

[Zakhary Shizai]

Do you know, in general, Afghanistan is seismically very active region, but not eastern Afghanistan is, compared to rest of the country, is very active. There are very active force in that area. And that area is located very close to the plate boundary between Indian and Asian plates. All these earthquakes are very shallow, even though we have some deep earthquakes in the northeastern part of the country. But luckily they are very deep and that they don't cause much destruction in the country. But the shallow earthquakes, they are very destructive and cause a lot of casualties in the country.

[Roland Pease]

And so when you're saying shallow, this is just a few kilometers deep. And that's a problem because we have.

[Zakhary Shizai]

Like three or four kinds of earthquake with regards to the depth. The earthquakes that occur from the surface to 10 km, these are shallow earthquakes. And the shallow earthquakes can cause very damage and destruction in that area. And because the energy that released during the earthquake can come very quickly to the surface and can cause very strong shaking.

[Roland Pease]

So that because it's a shallow earthquake, even though it was only a magnitude 6, that means it's really close, the source is really close to the buildings and so on.

[Daryl Seligman]

That's.

[Roland Pease]

You're saying this is why there's so much shaking?

[Zakhary Shizai]

Exactly. The main causes that was really shallow and close to the surface because of that, that caused very huge damage in.

[Roland Pease]

The area for you. Is there any more that you're going to do immediately about this earthquake? Are there things that you need to understand about it?

[Zakhary Shizai]

Yeah, of course. Right now still we don't know like whether this earthquake is from the current map faults there. We need, I think we need like a detailed map of the area we that know whether how many faults are there at the moment. And for that detail map we have we need very high resol. Very high resolution satellite Ms.

[Roland Pease]

I mean given that it is so seismically active, apart from being able to build houses in a better way, what can be done in a country which is obviously also very poor at the moment?

[Zakhary Shizai]

There are a lot of things like for example, there are not enough seismic stations in the country at the moment. There are like at the moment four seismic stations, two in the capital city, Kabul. And also the bad thing is there is no public awareness in the country. Like even there are many people, they don't believe this aircra earthquakes caused by tectonic plates or active faults. And this is a natural phenomena and can occur anytime. I think the most important thing is the public awareness to people and to understand this is like natural phenomena can cause casualty and destruction. We have to prepare against this kind of nature events.

[Roland Pease]

So in a sense you're saying this is partly a question of education to understand that this isn't fate, but this is the real world around them.

[Zakhary Shizai]

Yeah, absolutely.

[Andrew Destler]

Yeah.

[Zakhary Shizai]

Yes. They don't have like knowledge. You know, they are poor people even there is like very limited education. They don't have access to the technology. They will believe what they are hearing.

[Roland Pease]

Zachary Shinizai of Oxford University, who's hoping to return to the area soon to map out the damage and see geological evidence of the faulting. Always an important part of the learning after a deadly earthquake like this. Zachary finished on the importance of scientific knowledge when it comes to appreciating the parameters of threats from the natural world. What's to be trusted in science has become politically charged in the United States, not only on questions of vaccine policy, which we've talked about on the program. But this week a collective of 85 climate scientists put out a 400 page rebuttal to a report commissioned earlier this year by the U.S. department of Energy entitled Critical Review of Impacts of Greenhouse Gas Emissions on US Climate. When that was published in July, the standout conclusion was that greenhouse warming might be less damaging economically than commonly believed and excessively aggressive mitigation policies could prove more detrimental than beneficial. A far cry from what we normally hear. And Andrew Destler was soon coordinating experts from across the climate disciplines to assemble the line by line rebuttal. Just pub of the DOE report cataloguing what seem to be its many inadequacies.

[Andrew Destler]

I think inadequate is an understatement. The report is built on simple misunderstandings of the scientific literature, selective citation of the literature we call cherry picking, where you just pick a few studies that support your contention and you ignore a hundred studies that don't, misquoting studies where they quote one part of the study, but they drop the caveats. That's how you get to the conclusion that climate change is not a threat to human welfare.

[Roland Pease]

And there's a cover note on the DOE report from the Secretary for Energy saying climate change is real and it deserves attention, but it's not the greatest threat facing humanity. And you and your colleagues wanted to push back against that.

[Andrew Destler]

I don't think science can ever tell you what the greatest threat to humanity is. And so that's not what we're trying to do. Rather, our goal is to defend science, and defend climate science in particular. Climate science is probably the most scrutinized and reproduced science in the history of science. And for people to come along and say, oh, there are all these uncertainties that we don't understand is just, it's maddening to those of us that have literally spent our careers building up this base of knowledge. I certainly felt that way when I read the report. I mean, I felt the report was a mockery of science. And then I went on social media and I said, you know, who, who wants to write a comment? And lots of people responded. And I realized that everybody in the field felt this way. Basically, that's where the report came from.

[Roland Pease]

Their report starts off, I'd like to use this as an example. Their report starts off talking about the fact that elevated concentrations of carbon dioxide directly enhance plant growth, contributing to greening of the planet, which is a comment I often hear. Your first chapter pushes back on that in a big way.

[Andrew Destler]

I think that the argument that carbon dioxide is beneficial because it greens the planet is simplistic and facile, and it ignores a huge amount of literature that says that that's not correct. Look, if somebody's drowning and you're screaming at them, you need water to survive. That's not a very helpful or accurate characterization of the situation. Certainly plants do need CO2, but they also need a range of temperature that they've adapted to grow in. They need precipitation levels. When you add carbon dioxide to the atmosphere, you change all of those things. And so when you add all of those things together and you talk to the people who are experts on this, which is not me, by the way, but the people who wrote the analyses in our comment, they are very worried about food security in a warming world.

[Roland Pease]

One of the chapters which you are an expert on is that in the 1930s, during the dust bowl, there were exceptional temperatures in parts of the US and therefore those temperatures haven't been beaten since. And that means that there's no global warming. Again, this is a comment I often hear.

[Andrew Destler]

What the report says is there's no trend in extreme weather. They never say climate change isn't making extreme weather worse. And they want you to infer from that that climate change isn't making extreme weather worse. But let's take extreme temperatures. Okay, so extreme temperatures over the continental US you do find that there's no trend in extreme temperatures. The 1930s were very hot, and it is very hot today. And if you run a trend line through there, the trend is zero. But you have to look at the physics of the situation, which they do not do. And you have to understand that the 1930s were hot because of the Dust Bowl. It was a terrible, extremely hot drought condition with very high temperatures. It was not due to carbon dioxide global warming. It was due to a very local climate extreme that was due to some natural variability combined with some really terrible human agricultural processes. And then throw in a lack of rain and you end up with a dust bowl. Today, the temperatures are comparable, maybe a little bit higher, maybe a little bit lower. It depends which data set you look at. But the Dust bowl is not going on today. The physics is different. And the physics of what's driving extreme temperatures today is climate change. It's carbon dioxide. And so you have to look at this with more nuance than they did.

[Roland Pease]

And in both those instances, you're saying that these sort of illustrate the kinds of way that they're selecting data from that undermines the arguments that climate scientists like you are making.

[Andrew Destler]

That's right. It really seems to me that they are working Backwards. They know the answer they want to get and they just work backwards from it and they're not trying to get to the right answer.

[Roland Pease]

I suppose what I'm curious about is how important you think this report that they've put out is and your need to rebut. Seems to me that the government is able to make its own decisions whether or not this report comes out.

[Andrew Destler]

That's a really good point. I don't know what the impact of this is going to be, but ultimately, as a scientist who's devoted his life to science, my view is that you have to do the right thing. And the right thing is to respond to this. And they certainly, I expect them to do everything they can to avoid having to legitimately address our comments. We'll see what happens. I don't know what's happening. They haven't made any announcement about any of the details of the review process.

[Roland Pease]

I mean, I just wonder where this leaves climate science in the States. I suppose what I'm thinking is that the climate's going to go on changing if assuming the science that you're talking about is as good as it can be, whether or not some Department of Energy report is saying otherwise.

[Andrew Destler]

That's right. Climate change doesn't listen to reports, it listens to the rules of physics. And the rules of physics tell us it's going to keep warming as long as we're dumping carbon dioxide into the atmosphere. You know, I think the real risk for the US is that we're going to turn ourselves into laggards in some of the biggest economic sectors of the 21st century. You know, there was some recent reporting about how China is dominating in clean energy innovation. We know China's dominating electric vehicle technology. These are the technologies of the 21st century and we are just letting them have it. And so when people look back in a century and the US is a second rate economy and they say what happened, they might look at 2025 and say that was the year that we basically gave up competing on the technologies of the future.

[Roland Pease]

Andrew Destler, an expert on climate feedbacks at Texas A and M University and coordinator of that climate experts review of the US Government report on climate change. A reminder. This is Science in Action from the BBC World Service.

[Zakhary Shizai]

This is the story of the one. As head of maintenance at a concert hall, he knows the show must always go on. That's why he works behind the scenes, ensuring every light is working, the H Vac is humming and his facility shines with Granger's supplies and solutions for every challenge he faces. Plus 24. 7 customer service support his venue. Never misses a beat. Call quitgranger.com or just stop by Granger for the ones who get it done.

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[Roland Pease]

Technologies for reading Brain activity are improving at an extraordinary pace, and this week sees a pair of papers where researchers listened into the individual electrical signals from hundreds of thousands of neurons in mice rather than in humans to eavesdrop effectively on the process of decision making. Because thought involves large numbers of brain regions, it took several hundred electrode probes to collect readings from across the mice's brains, as Anne Churchland, one of the collaborators in the International Brain Lab, told me.

[Anne Churchland]

And that's part of what makes this brainwide map, an unprecedented piece of information that we're sharing with the community. It used to be that electrophysiologists would record small numbers of neurons. Maybe they'd measure activity from 20 or 30 or 100 neurons. But because of a new instrument that we used, these neuropixels probes, and because we shared the job of generating measurements across many labs, we were able to generate a data set that's a really large scale, both in terms of the number of neurons and also, moreover, in terms of the parts the of. Of the brain that we covered with this approach.

[Roland Pease]

And that's the important part is it's not just one part of the brain, but it's sort of a whole range of parts of the brain. So that you're looking for the correlations, as it were, between, I don't know, vision and listening or movement and so on.

[Anne Churchland]

That's right, yeah. So we're able to relate the activity of single neurons in all different parts of the brain to different aspects of decision making. And just as you said, those include things like seeing the visual stimulus, figuring out where it is, combining that sensory information with prior beliefs on where the stimulus might be, and then ultimately using all of that information together to prepare an action to report that choice.

[Roland Pease]

At that point, then the experiments are more sort of conventional, are they with the mice?

[Anne Churchland]

So. Well, in the context of our experiment, the animals were making judgments about the location of a visual stimulus. That is, is it on the right or is it on the left? And we manipulated the stimulus intensity. Sometimes it's very easy to see, sometimes it's very, very difficult to see because it's very, very faint. And so having those different kinds of stimulus intensities allows us to determine how sensitive each individual neuron is to the stimulus parameters. And it also sets us up well for a really important feature of our particular decision making experiment is that the animal had kind of a hint about the location of the stimulus by what we call a prior probability. So we had certain blocks where the stimulus was more likely to be on the left or on the right. We call that allowing the animal to develop a prior belief about the location of the stimulus. And when the sensory information is not very good, then relying on that prior is exactly the right thing to do. And that's exactly what the animals did.

[Roland Pease]

And so on each one of these occasions you sort of see, is it as almost like a wave of activity from one part of the brain to another, or give me a sense of how much the brain lights up, I suppose.

[Anne Churchland]

Well, yeah, that was one of the big surprises of the experiment. I think many of us in the collaboration certainly myself, kind of had in our heads a model of how decision making worked, which is that it included a small number of areas in the brain, probably most of them in the cerebral cortex, which is the outer shell of the brain. But what we found out was actually something pretty different, which is that we saw signatures of the decision making process in many, many, many structures, many cortical structures that we hadn't thought of, and even some areas much deeper in the brain that weren't even on our radar at all. One example we highlighted in the paper was something called the gigantocellular reticular nucleus. And honestly, none of us had really ever given it much thought at all. But this area turned out to have a key signature of decision making activity, of the animal's choice. It allowed us to realize that there are areas we weren't considering that in future experiments we probably need to consider, because they're probably involved in some aspect of decision making as well.

[Roland Pease]

I mean, what really struck me, looking at these papers, and they are so long, there's so much detail in them. In a sense, if you'd asked me before, I'd have said, well, the mouse sees something, the brain does some stuff, and then the mouse responds. And in a way it feels like you've filled in a really complicated jigsaw of what that actually is. But I'm not quite sure what the additional Understanding of brain activity is.

[Anne Churchland]

Yeah, well, I think there's a feature of the experiment that from the brain's point of view, makes it a lot more complicated than stimulus and response. And that is the fact that the animals, if they're clever, will base their decision not only on the stimulus, but the combination of the stimulus and their prior belief about where the stimulus is. And the reason that that's not a trivial computation is because you need to dial up and down the influence of that prior belief based on your confidence in the incoming sensory inputs. And we know that the brains of these mice are capable of making this sophisticated computation because the degree to which they use that prior belief depends entirely on how visible that visual stimulation. So they're able to dial up and down the way that they combine priors and sensory evidence based on the quality of the evidence at hand and presumably their confidence in that stimulus. So it's quite a bit more complicated than simply sort of a stimulus response reflex. It requires many more computations than that.

[Roland Pease]

I suppose what I'm also wondering is how do you translate this from mice to humans? Which I imagine is the ultimate aim of all this.

[Anne Churchland]

So, two thoughts on that. So, first of all, at the level of the behavior, this computation of combining prior beliefs and sensory evidence is something humans do all the time. So the nature of the decision is applicable to many other animals and absolutely to humans. But I think what your question is really getting at is how can we learn about human brain function and hopefully one day in a way that will benefit human health? I think another way forward that has clinically relevant applications is to be able to take our approach of looking at neural activity in young healthy mice and then apply that approach to a different context. For example, in my lab, we're now studying electrophysiological responses in the aging brain. And we've also taken the exact task that you read about in these papers, and we're using it to study a mouse model of one of the genes that is implicated in autism spectrum disorder. And so, even though right now we know which genes are implicated in autism spectrum disorder, at least we know many of them, we have a much less of an understanding about how these genes affect brain wide activity. And that's something that we're now in a position to figure out. And my hope is that this work will have tremendous relevance to human health one day down the line. Building on this foundation that we've created.

[Roland Pease]

Anne Churchland of the University of California, Los Angeles, on a pair of thought provoking papers in Nature this week, it's two months since we first talked about the discovery of Comet 3I Atlas here on Science and Action 3I because it's the third. Only the third interstellar object seemed to be coming through the solar system from far away in the galaxy Oumuamua and Borisov being the first and second. And ATLAS for the telescope in Chile that detected its fast motion well beyond the orbit of Jupiter back in July. Since then, it has been racing closer to the sun at speeds of around 60km s. Though unfortunately, its closest approach next month will be on the far side of the sun from us, which perhaps adds a little to the pressure to see what we can see on its inward journey. Daryl Seligman of Michigan State University has been coordinating much of the observational activity.

[Daryl Seligman]

The rule of thumb is that for a comet, you want to observe it at as many points throughout its orbit as possible because things can change on a night to night basis. And that's because as a comet gets closer to the sun, the amount of sunlight it receives increases. And so you can have lots of funny stuff happening, like different ices starting to sublimate, different jets turn on. You know, it could get much brighter at any given point in time. Presumably all of that crazy behavior is craziest when it's closest to the sun, unfortunately, when it's at perihelion. So when it's closest to the sun, it disappears. So we're not able to see it.

[Roland Pease]

From the Earth if that includes spraying then dust and gas out from its surface. Is that right?

[Daryl Seligman]

Yes, that's exactly right. So basically, as a comet approaches the sun, the sunlight will hit the surface of the object and heat up the surface a little bit. And as the surface heats up, what can happen is that there's ice. And when ice in space heats up, it sublimates, which is a fancy word for basically just goes from being an ice to being a gas. And then that gas, it blows off the surface kind of like a rocket. Then along with it, it'll bring material from the surface. So there's things like small rocks and dust grains and things like that will get blown off, off with the gas. So those beautiful commentary tales that you see, it's not actually the gas that you're seeing, it's the dust that's coming along for the ride.

[Roland Pease]

And I guess what that stuff is, is pretty interesting to you.

[Daryl Seligman]

Yes, for sure. One of the main motivations for studying comets is that they're the building blocks of planets. And the fact that this thing is a comet from another solar system it could be a building block of planets around another star. There is a huge amount that we could learn about planet formation throughout the galaxy by looking up close at something, an interstellar comet from another planetary system.

[Roland Pease]

As far as you can tell, are you seeing the same kind of stuff on this comet that you'd see on a solar system object? What sort of compounds are you seeing in that regard?

[Daryl Seligman]

It is acting a little bit weird. We have now seen water, but it looks like the tail is mainly carbon dioxide. And that is not what you typically see in a solar system comet. So it has to be a lot colder to freeze out CO2 than water. The fact that this object has a lot of CO2 in it tells you that whatever star it came from, it must have formed in a pretty cold region, probably around Saturn's distance or further, depending on the type of star it came from, which we don't know for sure. It could even be from a stellar system that has already died, which would.

[Roland Pease]

Be amazing in a sense.

[Daryl Seligman]

Yeah.

[Roland Pease]

As I say, this is kind of time capsule from another place. The fact that it's sort of going behind the sun when it's going to be possibly most interesting has really put the pressure on you to learn as much as you can before that time, I take it.

[Daryl Seligman]

Yes and no. I mean, I think the pressure is on regardless of when it disappears or not. Just because it's the third ever interstellar comet and it's been seven years almost since we discovered one. So I think even if it was observable at perihelion, everybody would be all code red, all assets moving forward, trying to observe it every second that you can. Overall, we're lucky that the orbit is such that we have many months to look at it. We gotta take what we're given. Right.

[Roland Pease]

I'm curious what you astronomers can do to try and get the maximum information you can from this comet as it flashes through the solar system.

[Daryl Seligman]

There's kind of like a wish list of things that I maybe in some crazy world we could do. And then there's the things that more realistically we'll be able to do. So why don't I start with the more sober, more realistic things? I think at least if we just do kind of comprehensive monitoring. So if we're able to kind of observe the object as close to us every night as we can with our telescopes and our satellites, that would be an amazing start. Because if you remember with Oumuamua, I mean, we were only had like a few weeks on that object, so we already have a lot more information about 3i Atlas than we ever had for Oumuamua. Another very exciting opportunity is that our space missions that we currently have throughout the solar system system could also observe it. And I believe most of them will be observing it.

[Roland Pease]

So they're on the right side of the sun even if we're not. Is that what you're telling me?

[Daryl Seligman]

Some of them. The answer specifically for each mission depends on the mission. But overall, yes, a lot of these space missions have instruments that they can and I believe will be pointing at their ATLAS to observe it, even when we can't see it here from the ground.

[Roland Pease]

You also talked about more unlikely scenarios you'd like to test out.

[Daryl Seligman]

Yeah. So we had this paper basically outlining how we could send a space mission to at least intercept or get close to 3I atlas. Not from Earth.

[Roland Pease]

I presume this must be a space mission which is already up there.

[Daryl Seligman]

Yeah, so that's what we were thinking. Technically, it is still feasible to send something from Mars. It wouldn't take that much fuel to go send one of those spacecraft from Mars and go visit through atlas. Because ATLAS gets. Get so close to Mars. It is an easier task to turn a spacecraft and look at three I atlas. So that is something that I think everybody is interested in doing. It's a harder sell to get them to go to get a space mission to abandon everything it's doing and go visit 3 Atlas. But.

[Roland Pease]

But you would love to, wouldn't you?

[Daryl Seligman]

That's right, yes. You could hear my voice probably, but yes, I would love to. To. But that's above my pay grade, so I don't get to make that decision.

[Roland Pease]

But if Daryl Seligman was in charge, I think we know which way he'd lead. The good news is that with the huge Rubin Observatory now scanning the skies from Chile, many more of these interlopers will be discovered. And the option of a strategically placed spacecraft waiting to catch one in flight looks increasingly realistic. When you catch the next edition of Science in Action, we'll have flown to Helsinki to join astronomers from across the globe debating the latest on planets, asteroids, comets and bold space missions. Till then, from me, Roland Pease and producer Ella Hubbard, thanks for listening.

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