StarTalk Radio - Space Archaeology with Sarah Parcak

Episode Date: July 23, 2024

Who really built the pyramids? Neil deGrasse Tyson and Chuck Nice learn about space archaeology, LIDAR, and discovering tombs, pyramids, and new Nazca lines with space archaeologist Sarah Parcak. NOTE: StarTalk+ Patrons can listen to this entire episode commercial-free here: https://startalkmedia.com/show/space-archaeology-with-sarah-parcak/Thanks to our Patrons Bo Cribbs, Anna Wheatley, Fred Gibson, David Griffith, Micheal Richards, Advynturer, Vici Bradsher, Terry Migliorino, Lingji Chen, and Audrey Lynch for supporting us this week. Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Chuck, I think everyone should have their own personal archaeologist. Is it Indiana Jones? Yeah, I'll take that. You just never know when you need one. That's true. Exactly. You never know when you're going to end up on a dig and just be curious. Just be curious.

What's buried here? What is that and why? Yes, exactly. I need an emotional archaeologist is what I need. Dig into your mind. I've just been burying so much over the years. All right. A little bit of space archaeology and more coming right up.

Welcome to StarTalk. Your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk. Neil deGrasse Tyson here, your personal astrophysicist. Got with me Chuck Knight. Chuck, baby, how you doing? What's happening, Neil?

How's it going? All right. We got a topic today we've never covered before. Yes, that's correct. We've been doing this for more than a dozen years. More than a dozen years. It's never come up. Today, we are devoting to space archaeology.

Oh, look at that. Okay, just to be clear, it's not going to the moon digging up fossils. Because there's none there. Well, there could be a reason for that, but we'll get to that later. This is specifically using space assets to help the archaeologists do their job. Oh, okay. assets to help the archaeologists do their job oh okay so basically they just hijacked your field that's what they did they jacked your equipment they just jet they satellite jacked you i think they had permission it was not a gun point so we we combed the world, and there are people who are experts in this.

And we found Sarah Parkak. Sarah, welcome to StarTalk. Thank you. Thank you so much for having me. I'm thrilled to be here. And I pronounce your last name correctly. Hard C, Parkak. Parkak, correct.

Sarah Parkak, archaeologist, Egyptologist. Egyptologist. That always sounds so cool. You're a PhD in this from University of Cambridge back in 05. And now you're a professor of anthropology, University of Alabama, Birmingham. And I love this, founding director for the Laboratory for Global Observation at that university. And recently you have a book sensibly titled Archaeology from Space, How the Future Shapes Our Past. Henry Holt, we share publishers in that name. Oh, cool.

One of my recent books is from Henry Holt. And is this true? You wrote a textbook, the first textbook on satellite archaeology, which means you wrote the book on the subject. I actually legit wrote the book. I did. Wow. Okay. Subtitle, Satellite Remote Sensing for Archaeology, published by Rutledge, a good academic publisher there,

and founder and president of Global Explorer, the X spelt just with an X, a not-for-profit company using tech to protect and preserve cultural heritage. I want to learn more about that in a moment. And you've also collaborated with NASA and the U.S. State Department. So you are the right person for any question

we might have on this subject. So let's get right in. Since you did write the book on this, what is space archaeology? Just put us on the same page here. Sure. So space archaeology is the use of sort of the general fun description or term for any use of space-based assets to map archaeological sites, whether it's NASA satellites, commercial satellites, drone imagery, data taken from airplanes. It's any kind of remote information that you might use to locate, whether it's a whole ancient archaeological site, whether it's a specific

feature on a site, or whether it's looking for things like, you know, buried ancient river channels that may show how and why ancient settlements moved over time. And, you know, that can be called satellite archaeology, remote sensing for archaeology, but actually NASA has a space archaeology program that funds scientists to do exactly what I do. So I figure if NASA calls it space archaeology, then it's a legit name. Okay, so Sarah, you need some more convincing for me of what you do, only because when we use NASA to look at other planets, their surfaces and the like,

it's because we can't go to the planet. So we need space assets to zoom in in places we cannot go. And so now you're telling me that a satellite either parked at 23,000 miles up or orbiting hundreds of miles up is somehow going to serve you better than you just putting your ass on location with a trowel. So tell me why one is better than the other. So that's really the fun part. And the whole point is to get somewhere on the ground to do survey, to do mapping, to do excavation. But, you know, anytime you're doing archaeology, you know, if everything were already visible, we wouldn't need to dig, right? So these are features, these are entire cities, these are

pyramids, these are tombs that have been covered over time by sand or soil or dense rainforest. And so what the satellites allow us to do is whether, you know, whether we're using different parts of the light spectrum. So think of it like a space-based x-ray or MRI. We're able to look at an archaeological site and we see these subtle differences on the surface because of how the surface soils or sand or vegetation is being impacted by what's buried below. We're able to get maps of what's there. And so, you know, think of like a dense rainforest that's covering an amazing site like an Angkor Wat where you go there on the ground and it looks like the site is,

you know, pretty big. But when you map it using lasers and you can do point cloud data and remove all the overlaying vegetation just by using laser data collected from airplanes, you're able to see the site is two, three, four, five times as large as you previously thought. So really, that's the strength of satellites. They allow us to see size, scale, and extent of sites and better plan our seasons that when we go there, we know exactly what we're looking for. What you're saying is, not to put words in your mouth, you have vegetation penetrating bands of light. Because obviously, if you're there, you have to cut through the brush and bramble.

But certain forms of electromagnetic spectrum cut right through that, saving you that effort. Right. So we use different technologies in different places. So for example, where I work in Egypt or any kind of open area, whether it's Morocco or Peru. Yeah, there's no jungle covering Egypt, last I checked. No jungle. So most of the archaeological sites are open and exposed, but the sand is covering the foundations of a temple or a tomb or a pyramid. And so what the satellites allow us to do is looking at, for example, let's just say it's a large settlement and it's made of mud brick. That mud brick, even if it's foundation, is going to hold moisture differently than the surrounding soils. And what the satellites allow us to do using the near infrared is map these subtle differences that are completely invisible to us with our normal visual eyesight.

And so just so near infrared, so we have the visible spectrum, and then there's this big band of infrared off to the side of red. And I'm fascinated that we use these sort of proximal words, near infrared and far infrared. It's a weird fact, but near would be like closer to the red and far infrared would be farther away. But what does near infrared do for you that far infrared does not? So near infrared is the best part of the light spectrum to map differences in vegetation and vegetation health. You know, when I'm explaining the light spectrum to my students, you know, it's so important because vegetation health can be impacted by what's buried beneath it. So it can be healthy or unhealthy, depending on if the roots are going into mud brick or

dense stone, or maybe it's in a ditch. Or even I've heard about some soil contamination can be uptaken into these plants. And then you can see regions of plants that are just simply different from other surrounding regions. Right. I believe they call that Monsanto i'm joking monsanto i know you're listening i'm joking you're not owned by bears so you're you're fine okay so we're able to see leaves right in the green part of the light spectrum because that's the information that is transmitted from them. That's what we,

from the light, but it absorbs the infrared. That also is important, right? Because we have to use computer programs to discern these differences that we can't otherwise see. So when you're looking at that from a satellite in the infrared, if you see like brighter leaves, does that mean they're healthier? Or if they're dimmer, they're not as healthy? Is that how that would work? So yeah, so that's exactly right.

So healthier vegetation, we see a brighter response. So it's going to have a higher value. And that's what we look for. And less healthy vegetation, we don't see the brighter response. So it's going to have a higher value. And that's what we look for in less healthy vegetation. We don't see the same information. But actually, Sarah, isn't it true? You're not there to value judge it. You're just trying to find differences. Right. Yeah. I mean, it could indicate a wall. It could indicate a underground water source. We don't know. But if it's a linear... so it's interesting though, like, you know, thinking about what we see and what we don't see and false positives. There was one time where I was

convinced there was nothing there. And it was actually a real positive that I thought was a false positive. That there was a very strong signature of healthy vegetation that was found in someone's backyard on this little island called Papa Store in Scotland. And they'd been finding Viking objects in their garden for years and years and years. And so this very strong signature showed up and I said, it's in alignment with their house. And typically when you see that it's like a buried water pipe or a gas pipe. And I dismissed it. I said to the team, we're not going to check that out, right? It's modern. But the team didn't listen to me. I was collaborating with local archaeologists. They're like, I think you found the Viking structure. I think that's what it is. I'm like,

no, it's not there. Could you listen to me? I'm the expert. So when I showed up, they're like, yeah, so why don't you check it out? And it was this massive Viking hall that was inhabited over hundreds of years by royalty and a king may have visited. So I was happily wrong to be wrong. And this is science, right? Sometimes we're overly cautious. Sometimes we need to throw caution to the wind and go with a super positive, healthy vegetation signature that turns out was a Viking wall. Tell me about LIDAR. We've all heard LIDAR. We know radar, right? Which is, of course,

an acronym. Or how you get a ticket. It's one of the earliest ever acronyms. Radio ranging, radio detection and ranging. Radar and radio waves, but the smallest versions of those radio waves are microwaves. And that's what the police use for your, it's still collectively radar. So LIDAR, is that just visible light? So LIDAR stands for light detection and ranging. And it sounds like, you know, something you might see in a Marvel movie. So a sensor system is flown on whether it's a helicopter or an airplane or a drone, and it sends down millions of pulse beams of light. And if you imagine you're in a dense rainforest,

you know, you're in the middle of the heart of, whether it's Cambodia or Brazil, anywhere in the world that has this dense vegetation. It sounds like you get around. I do get around. I do get around. It's a good thing my husband's upstairs. So, but yeah, he could confirm.

I do get around. And you're in the heart of this dark. I make a lot of jokes. Just let it go, Sarah. I was like, I'm not going to respond. I'm just going to let go, Chuck. I'm going to let that happen. So you're in the heart of dense rainforests.

But even when you're in the densest part of the rainforest, you still see light coming through. And what the LiDAR does is, you know, maybe hundreds of thousands of pulse beams of light hit the uppermost parts of vegetation. You know, hundreds of thousands hit the middle. Hundreds of thousands ultimately will hit the rainforest floor. And you end up with a 3D point cloud model of the entire landscape. And what software allows you to do is to remove all the dots that are above the ground. And you're left with what's known as a bare earth model or a digital elevation model. And if there's a pyramid or canals or terracing, any kind of structures that indicate ancient settlement in that area,

they are going to be obvious and clear in a way that isn't, even when you're walking through the rainforest. Or maybe you might say, okay, I can see the hint. Maybe there's a structure here, but you're not going to know exactly what it is. And that's what the LIDAR are doing. There's really this LIDAR revolution. But don't you need that at different angles through the vegetation because if you just go from one direction down and up you just maybe get in the canopy you're not just get the canopy right right in penetration for a different angle you're catching it at different angles as it goes along and so you end up with millions and millions of points oh i see because it's passing overhead and so if you constantly get the data, then I see.

And the point is to use a sensitive enough system, a powerful enough system to actually go through and get a certain number of points per square meter on the ground. You actually need, you know, between five and 12 points per square meter on the ground. And then you have very high resolution data. Topographic data. Yeah, for topographic data. And then you have very high resolution data. Topographic data. Yeah, for topographic data. And then you can create these models. And, you know, for example,

my colleagues at Tulane University just used LIDAR data. LIDAR in New Orleans. New Orleans, correct. Yes. They just use LIDAR data and they found 80,000 previously unknown structures and features around Tikal.

It was in science. It was a huge paper in science. In the science magazine, yes. Hi, I'm Ernie Carducci from Columbus, Ohio. I'm here with my son, Ernie, because we listen to StarTalk every night and support StarTalk on Patreon. This is StarTalk

with Neil deGrasse Tyson. How do you get below ground like a tomb or if you're talking about pyramids you know a lot of the pyramid for the burial parts are underground. So how do you get that? So to what Neil brought up earlier, so depending on what features you're looking for and how deeply they're buried, we can use a couple different kinds of data. So we can use radar data. So that will pass through.

That penetrates, right? That penetrates not very far, not as far as you think, maybe a couple of meters. Oh. It has to be in dry environments. So it works really, really well for detecting things like buried river courses, where you're looking for old settlements from maybe 10,000 years ago, deep in the Sahara. You can also use thermal infrared data. So this is the next part of the light spectrum. So you've got the near middle far infrared, and then you've got the thermal infrared, and that measures heat differences. So for example, let's just say you have a buried

chamber or a buried tomb, where the temperature is different, you're going to see that void that has a slight temperature difference and know. You'll know that there's an opening there or there's a space. Wow. I think generally when we think of infrared, we only ever typically think of temperature. I'm predator. Yeah. But infrared is light, just like any other part of the spectrum. And if you know in advance, you're trying to find subtle temperature differences, then infrared, that's your choice, right? And the other thing that we use is what I was talking about earlier, which is what's known

as active satellite data. So you have active and then you have passive, excuse me. So passive is most of the satellite data that I use. So it's receiving light that's reflected off the earth surface. It's not sending data down like LIDAR or radar. It's receiving that information. So that's where we're using different parts of the light spectrum. So the, the near middle and far infrared to look at things like vegetation differences,

soil differences, water differences. And then we're using pretty standard off the shelf remote sensing software. So we can just get it standard off the shelf remote sensing software. So we can just get it anywhere. We can get it anywhere. Like TurboTax. Yeah, just all over the place. And the great part about so much of the data that I use and my colleague use, it's free. You know, NASA has put millions, tens of millions now of their satellite imagery data sets online. And that's for kind of, you know, larger areas, but the commercial

satellite data, you know, you can easily get a satellite image of an archaeological site in the surrounding area for a couple hundred dollars. So it's not free, but also it's not going to break the bank either. You know, Sarah, in my day, we had to actually go to the sites. I just want to say, you know, you young... You can't hate on the fact that they found a smarter way to work. So once we have all this data, right, you know, whether you have, you know, your area that you've mapped, there's 100 potential archaeological sites or or maybe there are features on the site, we then have to do the really fun part, which is called ground truthing. So we then go to these sites, we go to these places. And instead of spending, you know, six months in the field, hacking through rainforest, or months and months of looking for things and hoping we find something, we're able to have a very targeted approach.

We know exactly where we're going. You know, today we are going to check out these 10 places. And with government, you know, cuts to funding, with having to really optimize our time in the field, it's an enormous time saver. That's like playing poker with a marked deck. That's kind of what you're doing. Why are people crass, Chuck? This is a noble work here compared to a poker game.

Plus, just the concept of a ground truth, I think, has its origins in the military, where you would fly over some region, and you'd think something was the troop movement or enemy movement, and you'd have someone on the ground verifying that who was right up close. I would radio you back and say, you can't handle the ground truth. And you know, it's interesting too. Did you know that aerial archaeology is the reason that we have all aerial reconnaissance in the military? It started in World War I when the first military planes were flying over Syria. There were amateur photographers from France and England, and they would take pictures of archaeological sites because they were archaeologists and hobbyists. They showed these to their commanders and they went, wait a minute, you can map things from the air? Oh, thank you very much.

Then the funding flowed like rivers. Right. Yeah. So Sarah, if LiDAR uses light, it seems to me lasers would be a very good source of light for this because you need the intensity and you see the reflected signal. I've used three different color lasers in my life, a blue, a green, and a red. All illegal. Every single one of them. Just because, Chuck, don't tell people.

So I would imagine that different color lasers, because lasers is monochromatic light, would serve different questions that you might have for the terrain. You know, as far as I'm aware, the lasers that are used for light are pretty standard. So the data we get from the lasers is the point cloud data. So there's no specific spectral information that's contained within that. You're only using it for the topography. Correct. Gotcha. And when you go to the site, so you've identified it from the air, and you say, okay, we have these 10 sites. When you go to them, are you trying to establish that you're going to now move on to excavation? Or are you just trying to figure out if there's something viable?

You think she's just going to stay home? You think? Really? Really? I'm just saying, there any do you ever come up with a dud it's like you know when you when you're drilling for oil there are a lot of times you think that you have found an actual viable site to drill and nothing's there in the old days that was much more common chuck but of course now the geophysics is way better today

so wildcat drills yeah it's way more efficient than because. So Wildcat drills is way more efficient. Because of her. That's why it's more efficient. They're actually using the exact same technology that Sarah's talking about. But I'm saying for your purposes, do you ever come up with a dud? When I first started, when I did this as part of my PhD, you know, it's science, right? We have to be critical about what works and what doesn't work. And when we go into the field to check, you know, maybe 85 to 90% of the time, there's

a thing there. There's an archaeological site and maybe one out of 10, oh, I thought it was a site, but there's this thing here instead. Okay, why am I getting a false positive? And then we refine our methodology and go back. But it's come a long way, you know, in 2025 years. And so the, you know, when I was doing my thesis, high resolution satellite data was five to $10,000 for a single image, I had to rely on the cheaper, lower

resolution NASA data. And now we have Google Maps. We're spending 10 grand a picture. Now a sick year pulls it up on their iPad. My son's like, mommy, you missed one. Right. I wish I were lying, but he's done that to me before. But this means that data, there's this great democratization of information now. and we have so much more to go through. And whether we're identifying something visually or identifying something using algorithms, using different parts of the light spectrum, it means we have to go back and reanalyze all of our data because of what we missed. So sometimes when we go into the field and you say, okay, I think what I have found looks like a pyramid, right? It's the same size and shape and extent. But maybe when we excavate it, okay, it's not a pyramid.

It's a huge tomb. That's not an L. Like, that's still a W. L for lost, W for win. Yes. Yes. Okay. To get the lingo.

I speak an 11-year-old now. My son tells me, take the L, mom. Take the L. It's in the W column i took him l but today i bounce back okay so but but the other nice thing about satellite imagery you know especially high resolution imagery if you're working in an area like egypt where maybe you're in sakara it's pretty well excavated there are hundreds of known tombs and you've got, you know, 300 discrete features that the satellite image has helped you to identify that don't look like there are any previous excavation

reports. We have all this data. So in archaeology, we go from the known to the unknown. And so we look at the tombs from the third dynasty, fourth dynasty, fifth dynasty, you know, the pyramid age, the age of the pyramids at Giza. And we look at their size and shape and orientation and relationship to one another, and we're able to make pretty good guesses as to what the things are that we have found. So maybe our grant from, you know, the National Science Foundation is to explore economic mobility of upper class individuals in the late Old Kingdom. And so we want to excavate tombs from Dynasty VI only. So that satellite data helps us to target what areas to excavate. Are there satellites that will help you find the lost city of gold?

Because that's what's truly important here, Sarah. No, no, Atlantis. Atlantis. That's what's truly important here, Sarah. No, no, Atlantis. Atlantis. That's clear. It's Atlantis. Or Atlanta, yeah. So Sarah, I wanted to pivot to Egypt because that's one of your specialties.

I have to ask a very blunt question. Please. What hasn't been excavated there? What is still there to learn? It's been there for thousands. What's taking you guys so long? Why isn't everything known? What is going on here?

Plus, it's not like Egypt was lost and buried and then discovered like Pompeii, all right? Egypt was always sitting there. Ancient Egypt was always there. So what does it mean to have a new discovery when we have a continuum of occupation and presence and awareness of that archaeological site. If you think about how long ancient Egypt lasted, so we're talking about a civilization that at its height lasted for approximately 3,000 years. But it, of course, continued after with the Roman Empire and then Muslim invasion and then medieval you know, medieval period and so on. But it came before then, too.

You know, Egypt had its origins deep in the western desert. So you have 7,000 plus years of occupation. But in the Nile Valley, if you think, you know, generally speaking, there were around 2 to 3 million people who lived there over that 3,000 year period. And the Nile is continuously depositing silt every year, which is causing the landscape to rise. So imagine cities and villages and towns and tombs and temples and pyramids for 2 million people over a 3,000 or more year period of time. That's a lot of places to find. A lot.

Okay. All right. I hadn't appreciated that it would be that many people. Right. Yeah. So can I ask you this from what you just said? And it's always puzzled me. It's one thing when you talk about waterways that are shifting and depositing silt and creating layers upon layers. But then

you see these dig sites that are in the heart of the city where people are still living, and buried beneath that city is a whole other city. How does that happen? What did they just go look we get we need dirt because uh we are tired of like let's just bury this and build on top what happens to create and then like when they uncover it's full you know structures that are intact and their interiors are intact what happens is it tragedy is it uh uh some kind of disaster? What causes that to happen? So some cities in the world, you both have traveled all over the place, and there are these magical cities that have these old vibes, whether it's Athens, whether it's Istanbul, whether it's Paris, whether it's Cairo, ancient Rome, right?

Yeah, Rome itself, yeah. Ancient Rome. I'm walking in a building, and so, oh, by the way, over here, the floor is glass, so you can see crypts that happen to be. Right. Meanwhile, I'm just trying to get a donut from the. That was the OG crypto, right? So you have these, I call them layered cities. They're places that were great to live thousands of years ago, and they're great to live today. They're everywhere, right? Like, look at what happened during the Olympics in Athens. They had to construct the subway, and it took them years

longer. They barely finished it in time because the whole process was an archaeological excavation. So, we as humans like to live in the same places, right? So we call them palimpsest. So these layers and layers and layers of occupation. Presumably because like the climate was good or the water supply was good or there's some feature that you're not going to go into the hills to escape just because somebody lived there before you.

Or a place like Istanbul, which is perfectly located. It separates Europe and Asia. Trade, commerce, access. Always a crossroads. Yeah, a crossroads, right? These crossroads, places that are magical. And it speaks to the great continuity of humanity. And so I wondered, I got asked that question all the time, Neil, that you asked me a couple minutes ago, like, how much is left? How can we possibly be sure? So I took all the sites that I found as part of my PhD.

So hundreds of sites across the Delta. The Nile Delta. Nile Delta, the Nile Delta. Okay, not Delta Airlines. No, not Delta Airlines. And I combined them with the hundreds of known archaeological sites in the Egyptian Delta. I then looked at all the known excavation data for all the sites,

and I calculated their area and volume. And as it turns out, in the Egyptian Delta alone, we have excavated one one-thousandth of 1% of the site. Okay, that's the answer. Wow, that's the answer. We know this much. We know nothing. Egyptology, we know nothing. This Wow. That's the answer. We know this much. We know nothing. Egyptology, we know nothing.

This is why all over the world, all the time, we keep making these amazing discoveries. All right, Sarah, get back to work. What are you doing on this show? I'm slacking. I only found 100 sites this morning. I know.

I got to go. I got to pick it up. Does my next question dovetail into your global explorer project? And let me just see if it does. into your global explorer project. And let me just see if it does. So if archaeology is no longer the province of professional archaeologists, because you are accessing the same data on the cheap as anybody else can access with a computer, has that turned the world into a raging circus of amateur archaeologists, each sure that they've made a new discovery?

So, yes, to your question. So, you know, anyone with a computer can look at Google Earth. You know, it's on everyone's phones if you want it. Everyone from the age of four, five, six, you know, whether they want to find mummies or pyramids or dig up dinosaurs, everyone grows up with a passion for the past, which is awesome.

It's a compliment to your field, right? Right, yeah. There's nothing like, I want everyone excited about archaeology because let's face it, massive cuts to the National Endowment for the Humanities, National Science Foundation, you know, museums are undergoing funding cuts, anthropology departments are closing in the US

and other parts of the world. If the public is interested and passionate, and understands the role that the past can have today for helping us to understand climate change and war and, you know, give us some hope, which we need more of, then that's only good. We want people participating, then that's only good. We want people participating, but participating in a guided way. So this is one of the reasons that I started my not-for-profit Global Explorer. So back in 2016, we built an online citizen archaeology crowdsourcing platform. So this gave some structure and an umbrella under which this activity can unfold. So it's not just random at this point. No, I mean, so we started the platform with archaeological site data from Peru.

So we had the full buy-in from the Ministry of Culture in Peru. We were collaborating with a number of Peruvian archaeologists and specialists. That means you have the Nazca lines and the NASCA patterns on the plains of Peru, right? Correct. Yeah. So the data that the crowd used and the data that the crowd generated, so the crowd ended up finding almost 30,000 potential, we called them anthropogenic features, so suggestive, we're very careful. So we then looked through all the data and over 800 of them were determined to be significant, previously unknown discoveries. So these are sculptures or structures or paintings or some surface features on Earth. So forts, settlements, potential tombs, suggestive structures that are on the earth's surface.

And we then gave that data to colleagues in the region of Nazca. And in looking for the sites that the crowd found, they found new Nazca lines. So this collaborative project helped to support great local archaeological work and gave them a new perspective and allowed new discoveries to be made. So that's what we want the data to do. We want to harness the power of the crowd and everyone's passion. And some people got really, really good at finding sites and features. We had some super users that found hundreds of features. And then that can help people on the ground who have the qualifications to go out and excavate and map. people on the ground who have the qualifications to go out and excavate and map.

But there's still renegades out there for sure. And what do you do about people who just, whose imagination is put forth as a substitute for science? I believe that's called America. I believe you just described the entire country. That was a damn good sentence. I don't even know if I can repeat that. So we're having a moment right now in our country where the value of experts and expertise is coming under fire. It was exacerbated, of course, by the pandemic. There's that famous, I think it was a New Yorker cartoon, some guy's on an airplane. And he's like, come on, we can pilot better than the pilot. Let's go.

And you're like, what? And so, so archaeology, that's not real. I can dig. Digging, like digging is what my toddler does. What are they? So people don't understand or appreciate, you know, that it takes years and years, decades of training. I'm still learning. Every time I go into the field, I've been doing this for 25 years.

I'm still learning. Otherwise, you regress. If you're not learning every day, you might as well move backwards. Right, and people like me get accused of gatekeeping. Oh, you think you're better than everyone else just because you know how to date. It's like, if I have a problem with my heart,

I want a qualified heart surgeon. I don't want Edna on Facebook to tell me to take herbs. There's a YouTube video that you can just operate on with my heart. I want a qualified heart surgeon. I don't want Edna on Facebook to tell me to take herbs. No, no, no. There's a YouTube video that you can just operate on your own heart. I saw it. And who needs a YouTube video? I like to feel my way through these things. Yes. It's fun, man. I have a feeling. I've got the right cardiology vibes right now. Yeah. I just have a knife. I have some rubbing alcohol. I don't want to discredit people's passion, right? There are so many great people online who are excited. They're enthusiastic. They have good ideas. They just don't have the training. They don't have the framework. And I wish more of them would take

archaeology classes because I think they could all make real contributions to the field that are valid. The problem is that your archaeology classes, they don't support the field that are valid the problem is that your archaeology classes they don't support the fact that everything you dig up was put there by aliens sarah i don't know if you know this but everything that you guys dig up was put there by aliens previous civilizations right exactly and isn't it interesting, Egypt, Central America, Peru, Great Zimbabwe, India, it's all aliens. But Rome, Stonehenge, I don't know what that could be. As much as I love the movie Stargate Atlantis,

it still had the pyramids built by aliens. Right. The Africans somehow didn't have that ability. Stargate Atlantis, it still had the pyramids built by aliens. Right. Right. Yeah. The Africans somehow didn't have that ability. You needed the aliens. Right. And what I tell people, I was at a lunch years ago with some interesting people and they all said like, well, come on, aliens, right?

You can't go to the pyramids and look at the pyramids and be like, how is this done by humans? I'm like, okay, fine. Give me three minutes. Give me three minutes. I will prove that the pyramids were not built by aliens. Oh, do it. Please. Can you do that?

So I pull out my phone. I pull out my phone. Well, first you have to punch him in the face. Well, yeah. I do victory dance. So I hold up my phone. I'm like, was this built by aliens? They're like, what do you know?

You know, Steve Jobs and the iPhone. And so I said, so, you know, you go back, whatever, 5,000, 6,000 years in Egypt. And first steps, you know, they put their dead in the ground. Is that aliens? We're like, no, that's normal. You bury your dead underground. I'm like, okay, well, then like dogs dig them up and start eating them. And that's gross. So you start putting stones on top of them to protect them from dogs is that aliens they're like no that's again normal i'm like right so things

develop and there's social stratification and soon you know the wealthier people the leaders you bury them with pots and goodies and they're and and but still there's stones and aliens no still no aliens well then they start getting fancy with the stones and they start like building superstructures and making a little more formalized and society gets more organized. That aliens will know that's normal. OK, well, things start getting bigger. We're able to see this in the archaeological record. Soon there's more chambers and more stuff. Is any of this aliens?

No, still no aliens. All right. chambers and more stuff. Is any of this aliens? No, still no aliens. All right. Well, so they get bigger and bigger and bigger over, you know, a 500 year period of time. And soon, you know, they're building huge structures out of mud brick. Aliens? No aliens. And I said, and then along comes Imhotep, the genius architect, the Steve Jobs of his time. And so he takes this very large stone built tomb where we see, you know, hundreds and hundreds of examples going back 500 plus years. And he looks at it, he's like, yeah, I'm not going to be extra. I'm going to stack them one on top of the other. And I look at them, I'm like, what does your three-year-old do with blocks? Well, he stacks

them. I'm like, right, just like Imhotep did. That was the start of pyramids. And then slowly over the next sort of 300 years, they get larger and more complex, and eventually they get smooth sides. Sure, clearly Imhotep was the alien. That's where I was going. So that's it. It's human genius. It's human innovation over hundreds and hundreds of years.

And it's a progression that you see over a long period of time. They didn't land from space. There was a prior story there. So Sarah, as in most branches of science, and particularly where very precise tools, tactics, and techniques arise, often they can be applied in other ways. And I can't help but think that everything you're doing here on Earth can now be applied when we're mapping the Moon or Mars or Venus. Ooh, that makes us the aliens. We are the aliens. We are the aliens. Ah, the aliens.

Looping on other planets. So in what way has your field or the technologies of your field, satellite archaeology in particular, been co-opted the other way now? We're just starting to have more and more conversations with planetary scientists, with NASA. I've been kicking around some ideas with our wonderful colleagues at SETI. around some ideas with our wonderful colleagues at SETI. And, you know, if you look at the Drake equation, right, when Frank Drake came up with it, we didn't know how many exoplanets there were capable of supporting life. And now, you know, there's, I don't know how many, I don't know how many, there are hundreds. Oh, capable of supporting life as we know it. Yeah, it'd be in the hundreds. Hundreds. Out of the catalog of right now rising through 6,000. So the question is, as and when and if, but I think when, I believe there's life out there.

But the question is, if there's advanced life, what will it look like? How advanced will it be? And it could be that we find a planet where, because of a catastrophe or whatever reason, that civilization ceased to exist a million years ago, but it's still there. So what is it that we're doing and how we're mapping things on the ground that could help us to unwrap, unshape, and decode what these places could have been like? And archaeology is the way to do that, not necessarily through space archaeology that will help us map it, but archaeology is the way to do that, not necessarily through space archaeology, that will help us map it, but archaeology provides us a framework to reconstruct how

entire civilizations evolve. The huge intellectual capital of invested brains thinking about that, in ways that the astrophysicist wouldn't. We don't think of civilizations in that way. Who needs civilization? We don't think of civilizations in that way. Who needs civilization? Yeah, we just don't have that training. I mean, we'd love to bring you on board for sure. I love jamming with other scientists because, you know, of course, everyone's got great ideas. And there's so much that I don't understand, appreciate, know about how and why things develop on planets.

And the idea being like, where could we find this life? Could beings exist that have evolved to live in extreme temperatures, right? Which is why we're studying life around heat vents deep in the ocean. What are different ways that we could think about life? You know, octopuses, they make houses. Like that's amazing.

They construct their own little mini apartments. You know, is that what an alien civilization would look like? Like an octopus condo? I don't know. But I think we could create tools to help people think about ways of mapping them. This is how science builds on science. Yeah. Because not everyone can know everything going into a problem.

Even Einstein, who laid the entire framework for the discovery of black holes, did not even predict their existence because it was outside of his thoughts. And he was even in denial of it for a while. I can't stop thinking about octopus house warmings now. No, because he's got a house. That's a little fact that you just threw out there that we kind of let it just fly, but I'm like, wait a minute. I have a completely different view of octopuses now, just showing up to each other's house with a little bottle of vino, just like, hey, nice place you got here. A selection of eight bottles from the case of war.

Nice place you got here. A selection of eight bottles from the case of oil. Excellent. Well done. Well done. So what is this here about using archaeology to study the space station? Is that a thing? So that also is a form of space archaeology. I think, you know, the idea that we can use this technology to view how other places are inhabited and how and why it changes over time.

You know, my colleagues who are studying the space station and moon artifacts, it's amazing work and so essential to understanding, because for now, like that's all we have. We have the space station. We have to figure out what do people leave behind? What's the ephemeral evidence? What are things that we need to consider? And it's fascinating. So it's a space version of your multiple civilizations because the ISS has been up for 25 years or 30 years or so. I was being assembled in the 90s and different nationalities are there.

They eat different foods. So are you referring to the run of human culture as it has been expressed in that space. Yeah, and changing technologies, innovations, breakages, additions, studying how the space evolves both from the outside and also on the inside. Right. Where did they put the 286 computer? Did they bring it back to Earth? Did they just stick it outside so it's still floating by? Right.

As times modernize, old things become obsolete. And what do you do with it? And it's all just contained there if not brought back. Right. That's pretty wild. One thing I was going to mention earlier, people have considered looking for fossil remains of life on the moon from ejected rocks from asteroid impacts on earth. Oh. And then they would float through space because we have moon meteorites on earth that we didn't

have to go to the moon to get. Right. Really, the moon has been hit before. And so rocks get cast into space. Some arrive on earth. So we have huge supplies of moon meteorites here on Earth. And if that's the case, presumably there would be Earth meteorites on the moon. And then you go there and look for any stowaway microbes, not thriving on the moon, of course,

but there'd be evidence of them having once existed. So any of your people thinking about that, Sarah? No, I, I, wow. I mean, you, I, it's the first I've, I've heard of it just because it's, it's so, it's very inventive. Yes. Awesome. It's super cool. I mean, I, you know, the question is like, what size would they be? I know that the moon is incredibly well mapped at a very high resolution. So the question is, you know, where could they be? Are there places that they would, where we'd be more likely to find them?

Yeah. And how much of that meteorite would remain intact upon colliding with the moon? So there are other factors here, but once we learned that rocks move between planets, this became a very easy next thought to have about and by the way and the fossil record going back to the moon would if it was preserved would be intact over the thousands millions and even billions of years it's been sitting there because there's no erosion there's no weather there's no subduction uh continental plates is just there and so maybe that's another frontier and the question i would have is would would those rocks would they have a

discrete spectral signature compared to the surrounding right and they would pop out then they would just reveal themselves right so we we just need one you are being lazy again let me just sit back and work smarter not harder but that's an amazing idea like i i would love to help with that kind of project yeah cool very cool hey is there a thread that as you span span the globe that is the most common thing amongst the cultures or civilizations that you dig up? So that's a wonderful question and no one's ever asked me that before. And it's the subject of a book that I'm working on right now. So the book, it sort of inverts the idea of collapse and is a very hopeful look at how and why humanity lasts so the thing i think that connects humanity or civilizations local civilizations humanity humanity generally the idea of continuity that is the thing that

connects so many of these sites and places um that i and my colleagues have mapped all over the world that wherever you go people last and you know kings may stop ruling there may be environmental change climate change war disease but culture persists people persist and to me the idea that so many of these places today, to the point earlier that like so many cities are built on top of old cities, we last, we persist in spite of all of these awful things, some of which we have no control over, some of which we have great control over. very hopeful in the face of all these awful things that we're staring down now with climate change, with war, with the rise of authoritarianism. So the work I do gives me hope because of how long we've lasted and where we've lasted. Wow. That's a tone to end the show on right there. Anything that gives us hope, I'm all in. Tell me about it. Bring it on. Bring on more hope. Please. Give me some hope. Oh it on. Please.

Give me some hope. Oh my gosh. Anyway, it'll be out in a couple of years, so working on it now. Well, good luck on that. Sometimes you need a little bit of luck when writing and publishing a book. Especially when it's about hope. And your 2019 book with Henry Holt, Archaeology from space how the future shapes our past how

the future shapes our past that's a that's a twist on the timeline right there that's a marty mcfly moment for those of you who are listening it's your kid marty speaking of back to the Future, I understand offline that you're a big sci-fi fan. We love sci-fi fans. Huge, huge sci-fi fan. Huge. What a note to end on.

Let me see if I can take us out with a cosmic perspective. You know, when you're in school and you learn about the various sciences, no matter what course you take, there's a book and there's a book on that subject. Then you learn it and you do as best you can on the final and then you move on, often leaving the book behind or selling it on graduation. Whereas people who are deeply curious will know and recognize that we divided the science into these categories.

Nature didn't do that. We did. And if you look at the cross-pollination of statistical tools, of mechanical tools, of electronic tools, of methods that overlap between one science and another. And then you realize we are all just curious children poking at what sits before us, what's under that rock, what's behind the tree, what's up in space. We're all the same species, those who ask questions and those who look up and down. These are two directions where there are frontiers that persist. And so I'm delighted to learn that tactics, methods, and tools of the archaeologist

can be applied to space and vice versa. A reminder that maybe all the branches of science are not as far apart from one another as we might think as we're struggling through them in school. And that is a cosmic perspective. This has been StarTalk. Sarah

Parkek, thanks for being on. Thank you. This has been so much fun. Thank you, thank you. And Chuck, always good to have you, man. Always a pleasure. This has been so much fun. Thank you. Thank you. And Chuck, always good to have you, man. Always a pleasure. This has been Star Talked. As always, I bid you to keep hooking up.