The Tunnelers

I mean not directly. I mean we might ponder, as we uh we read here what the metaphorical ball rog might be in all of this. But but it is gonna be an episode about about digging in the earth, about about about mining down, digging down, and just how deep we've gotten. And then what do we do in the earth? What's what is what? What? What is Homo sapiens business beneath the surface of the earth? After all?

You know what? I just recently went to the Atlanta Zoo and I hadn't been there since I was a kid. And first of all, it's fantastic. Atlanta Zoo is wonderful. But one of the things that struck me the most was when I went into the little area where they have the places where you can view the naked mole rep Yon, where there is this The smell is overwhelming. Uh, there's this odd odor. But just looking at them, they

are one of the strangest looking creatures on Earth. There these naked, wrinkly, uh, kind of rosy pink things with long teeth, lying in puddles, appearing to have some kind of high mind and and frequently, at least when I was looking at them, chewing on each other, just gnawing on one another beneath the ground. And these are true like subterranean creatures. You're not that we're designed to live on the surface, but we do a lot more underground

venturing than most other permanent surface dwellers do. Absolutely. And on the subject of of underground true underground evolution and the evolution of burrowing species, I would like to come back to that because we actually have um an author in the Atlanta area wrote a book about the evolution of burrowing creatures and uh, and I keep meaning to to reach out and see about having him on the show to chat with us about it. He's the one. He actually mentions tremors the movie in the book, so

you know, you know that he's our people. But speaking of of our people and speaking of of underground creatures, one thing I was thinking about two is how if you look to the fictional world of subterranean humanoids, we see there's always there's pretty strict dichotomy. Right on one hand, you have the debased underworld dwellers. You have the moment the crawlers from the descent, the more locks for the time machine you have or one of my other favorites

in terms of just cave dwelling creatures. Two gargoyles. I don't know. Oh, it's terrible, some wonderful gargoyle costumes come creatures coming out of the deserts and the desert caves and kidnapping people that sort of thing. Well, I usually think of gargoyles as as flying. Yeah, but they live in caves in this particular movie, somewhere where they gonna live in the middle of the desert on a skyscraper.

I guess bats live in caves and they fly. Yeah, they're basically It's more it would have made more sense if they were bat people. Instead of gargoyles. But um hey, I invite everyone to to see this film for them for theirselves. The the ideal way to see this film I think was probably at three pm on a Sunday on TBS back in the day. But you can watch it through modern means as well. Oh, I just looked it up. These are some striking images. The gargoyle is

almost cramp us looking it is now. Of course. The more Locks though, are really more of the iconic underground dweller though from HD Wells The time Machine. Yeah. Though, the interesting thing about them, so you're saying that there are some uh, some fantasy and sci fi works where underground human oid type creatures are presented as like, in some way like a horrible deviant version of us, where the more Locks are the sort of the villains of

the time Machine, but they're also it's funny. In the novel, the more Locks are like the intelligent creatures that use technology, and it's the the gentle surface dwelling eloi who are like kind of ye, they're flacid and in curious and sort of bovine. But then we also have works where the creatures who live underground are the more refined humanoids. So um, we could of course looked in the Middle Earth and the Dwarf Lords in their Halls of Stone.

You know, they're not elevated to the same level as the elves, but but still they're an advanced civilization that that seemed to to to love a good underground uh empire. Then you have things that you have, and you have other groups like the drought in Dungeons and Dragons, the non men and our Scott Baker's Second Apocalypse socca. The mutants in beneath the Planet of the Eights. Oh yeah,

they worship a giant bomb. Yeah, they're great and they have psychic powers, and yet we have not seen them in any of these recent Planet of the Apes movies. Also in the Fallout games, you have the Vault Dwellers. They're not permanent to underground dwellers, but they have dwelt underground for a long period of time and they have internal and you know, emerging into the surface world to

retake it. Well, yeah, I think clearly in a lot of these like science fiction works, the underground humanoids it's supposed to be something symbolic. It shows like a sort of like retreat into some kind of other nature. It is a physical sign that something has changed. And I think another out of the appeal is that the living below ground or in caves or vault is something that seems like it should be rather removed from the sort

of homes that most of us keep. And yet one of the curious things is that underground dwellings are also a part of our past. Uh. They're they're part of our present, and depending on where we go in this solar system, uh, they may be a part an important part of our future. Yeah. So let's take a minute just to to talk about humanity's history in the depths

of the earth. Okay, So limestone caves provided shelter for the Neanderthals of the Ice Age, and early humans too made use of caves for shelter but also for burial and for sacred rights. Yeah, I was looking at examples of this. One example of I think the religious significance of deep cave dwellings, especially by Neanderthals, is to be

found in the Brunkel Cave of southwestern France. Uh So, to decide a journal article, We've got one in Nature here from twenty sixteen called early Neandertal constructions deep in in Brunickel Cave in southwestern France by joe Bert at All And in this study, archaeologists reported the discovery of ring shaped patterns of broken still agmites made from about four hundred pieces of still agmite that are that were

found deep in the cave. And we don't know what these ring shaped structures were for, but it's clear they're artificial in origin. They were made by by humans and they were the site of ancient fires, where like there are some sections that are burned and charred, and there are also pieces of burned bone mixed in with them. And a uranium dating series combined with some other methods gives the structure an approximate age of a hundred and seventy six point five thousand years old, one of the

oldest known human structures. And this was pretty deep down to oh extremely yeah. This was found three hundred and thirty six meters down from the entrance of the cave. That's over eleven hundred feet down, showing that the Neanderthals who made these rings had master deep underground environments. Like to go this far down is not something an animal would do lightly. You'd need to have an artificial light

source to take with you. You You probably need a plan in a way of organizing and understanding your spatial environment so you don't get stuck down there. And the big question is what were the rings for? We had these rings over a thousand feet down underground. A common explanation would be, well, it's maybe religious in nature. Somebody's burning fires with rings of stone down in the dark over a thousand feet underground, right, must be for some kind

of ritual. We don't really know, but it's fascinating question, and I think the most common answer is probably that it had something to do with with an with a loss to history, unknown neandertal religion. So there yet, so there was a sacred reason to go down into the depths presumably, or maybe there's just some other reason that we don't understand. It doesn't it's not clear. Is it's not easy to determine that these this like circle would

serve a practical purpose. I'm not sure what you'd use it for as a tool or anything like that, or why I would need to be so far down if you did it. Almost it really asks for a kind of symbolic interpretation. Yeah, Now in terms of more readily accessed portions of a cave. Stuff close to the surface. It's easier. It's easy for us to to think, well, you know, these are the kind of early primitive shelters one might use, and then you would quickly evolve beyond that.

You would reach the point where it just makes more sense to depend on tents and buildings for your shelter um and then you would would maybe only stick to the depths for you know, things that are religious in nature, like catacombs or or perhaps bomb shelters in some cases, or basements. I mean, it's, uh, it's easy to think that there would just come a time where nobody lives underground anymore unless you absolutely have to. Well, yeah, and

there'd be several reasons for this. I mean, one would be the advent of settled civilization, because it's not that there are no sub old civilizations that involve caves. Some of them do involve caves, but generally there's a limited number of caves out there, so you can't just like keep filling up caves. You need to like build your own structures to support and expanding population, and caves are not necessarily near where you can do your agriculture, right.

And then if you're expanding on caves or or setting out to build your own caves in the form of artificial tunnels, it takes a fair amount of of effort. You have to have considerable resources, technological know how, and you have to depend on the rock that you're working with being the right temperament for what you're trying to build. However, we do see all of these things line up, uh in really to a fascinating degree with some of these

caves cities in modern day Turkey. Um and I was was not really all that familiar with these prior to researching for this episode, but they are, They're amazing. Uh. One in particular is the city of Daring, who you h This is a complex of hand dug tunnels that dive down sixty meters or two hundred feet um beneath that's as roughly eighteen stories beneath the surface and would have housed and estimated twenty thousand people during its heyday.

It contained homes, schools, even a winery, and it's likely that these tunnels were begun around seven b C. And while it eventually seems to be a functional, fully functional city, it continued to serve as a place of refuge well into modern times, the place that surface dwellers knew they could they could flee to and hide in. You have surface tensions, we were too problematic. Yeah, it seems to be worth noting that this is what the majority of

these Turkish underground UH dwellings were primarily used for. It kind of calls to mind to go back to the Lord of the rings, like Helm's Deep, right, it's a place where if your civilization is attacked, you can retreat down below the surface and we're in seal up the walls with stone until the war passes on or the

danger is gone, and then you re emerge. Which makes me wonder about the Neanderthal a mystery from earlier, like, to what extent was that a way to survive uh, the new people, you know, the inheritors, to to to flee down into depths that that other uh certainly surface predators, but maybe even uh these newer hommaid species would not bother with. Now that'd be a good plot for a novel, but I think it is the case that Homo sapiens are not believed to have been in the area at

this point. Oh no, no, for purely Hollywood reasons, it could be like a reverse descent instead of it being uh, poor hapless humanoids dealing with underground monsters are underground monsters of the heroes. There you go do for the descent three, That would be actually a pretty good uh way to frame it. So again, this is just one of of several underground cities that you find in this region. There's also the Kaimak the Underground City, the Oscanic Underground City,

there's the Mazy Underground City. And there are some interesting illustrations of these online that really just drive home what we're talking about. We're not talking about like just a few chambers. We're talking about like multiple stories of underground habitat.

It's a luxury mine. We should also point out that cave dwellings continue to this day in parts of the world, such as with Waddox, a southern Spanish region containing around two thousand caves that have been used as homes for generations. And you look at pictures of these and there's really quite uh. The design is very interesting to look at because in many cases, like the walls are painted, they look like rooms in in home. You know that they

don't don't look like cave dwellers. They look like relatively modern people living in a shelter that just happens to be part of a naturally occurring cave. Well. They're also still underground homes in Tunisia. In fact, some of these underground homes make an appearance in the first Star Wars movie. So Luke's house in the first Star Wars is you know Uncle Owan and Aunt Brew where they live. That's sort of modeled after a type of Tunisian dwelling where

there is a central crater type structure. It's like a big pit in the ground, and then around the ring of the crater there are dugout rooms that you can go into. Very interesting. I didn't realize that. I always thought it was just an elaborate set, I guess, or an actual space house. I didn't think about the idea that this would be an actual home or based upon an actual home design from that region. There's a cool photo gallery on on the Atlantic website that that documents

some of what these houses look like in more recent decades. Cool, and there, of course other plenty of other examples we can point to of sporadic underground dwellings they're parts of Australia where you still see a fair number of underground dwellings.

And then I feel like, at least when I was growing up, there were at least a couple of underground houses in the county where I lived, because there were there's a lot of tornatic activity in the region, and there was at least one house where It's like somebody was like, screw it, I'm not putting up with this fear of tornadoes anymore. I'm living under the ground. And then they did it. Wow. Yeah. In fact, I think I knew somebody who lived in an underground house in

southern Middle Tennessee. It's all basement. It's all basement. Yeah. Well, I guess that has certain advantages. It probably a certain disadvantages too, I would I would think, for example, the lack of exposure to sunlight would eventually psychologically get to you. Oh yes, And that's a that's of course, that's a whole other side of the equation when you start imagining permanent dwelling underground and what that does to our circadian rhythms.

But generally speaking, we're thinking about creatures that are going to come back out again with with with regularity to obtain the resources they need. You would kind of have to write because I mean you mentioned that, for example, the city uh in an ancient Turkey, this underground city. It had like a winery, but it couldn't have a vineyard under the ground, right, and then they weren't making mushroom wine, um likely. So you know, we mentioned the Descent.

Even the monsters in the Descent were leaving their caves to pray, because there's the whole scene where their bones piled up. They have this uh this is these midden heaps of the things that they've been eating, and it's it's it's shown that they've been eating deer like they're going to the surfaced hunt, presumably at night. So yeah, we have plenty of underground to have it as today. And also certainly if you go to a major modern city, you go to New York City, you're gonna find plenty

of people living in basements. You know that there there there's there's still an underground too many um surface dwellings that rise into the sky. And then we have plenty of underground complexes that can sometimes be repurposed as a shelter. For instance, we did uh an episode talking about mosquitoes in the London underground and their evolution, and we in that we discussed how during the Second World War the London underground, the subway system there was used as a

bomb shelter. And then we have cases of homeless individuals living and abandoned subways, railroads, flood sewage tunnels, heating shafts in various metropolitan areas around the world. Uh. If you've ever seen the two thousand your two thousand documentary Dark Days, Uh, that documentary looks at people living in Freedom Tunnel in

New York City during the mid nineteen nineties. So thus far we've looked at religious reasons, survival reasons, um, infrastructure reasons, even a little bit to dig tunnels under the earth. But another major reason to go digging around and crawling around under the earth like you're some mener of worm, is of course, to mine precious resources, find that pot of gold exactly. In fact, we just talked recently in an episode of Invention the role that copper mining might

have played in the origins of wheel technology. That's right, So humans figured out that these were press as resources that we could do things with them that give us a very important advantages over our fellow humans, and in doing so, we quickly ate up all the the easily acquired deposits of these materials. So instead we just started digging a tunnel. There's more down there, right, and then you need you need things like like wheels to remove them from those tunnels. So we do find plenty of

examples of pretty old minds in human history. The oldest mine in the world is thought to be the the Church Silica mine at Naslette Sabaja in in Egypt, and it's estimated to have been in use around a hundred thousand years ago. That's crazy old. That's long before like settled civilization, long before agriculture. And it's in mining that we find some of the most incredible feats of tunneling, uh,

even before the twentieth century. So in Kimberly South Africa and South Africa is a region where we see some some pretty incredible, slash terrifying feats in mining. Um between eighteen seventy and nineteen forty, fifty thousand laborers moved twenty two million tons of earth and reached the depth of seven hundred nine ft or two hundred forty in search

of diamonds. And this is uh, this is a dig that's currently not known today as the Big Hole, and it is considered the largest hand dug pit in the world hand dug yes, well that yeah, so not using you know, a bunch of mechanical aid. Less impressive certainly from the air, but still pretty impressive in its depth. Is uh is woodingden Well in the UK. It's an impressive hand dug well that reaches h one thousand, two hundred and eighty five ft or three hundred ninety into

the earth. And uh BBC's the deepest holes dug by hand points out that it's as deep as the Empire State Building is tall. And that's just well, that's the hand dug well. Well, I think they did well. Uh, let's say on that note, Yes, let's definitely take a break, folks. You should know I just said that and then I said we could cut it, and then I said it again, So it's got to be time for a break. Thank Thank Alright, we're back. So let's talk about some of

the modern day marvels of digging in the dirt. Uh. Modern minds are even more impressive because, of course, we have enhanced tunneling machinery that allows us to be dig deeper, dig harder, if you will. And also, of course we have just better ability to blow up the rock and do so in a way that actually achieves our goals

of digging deeper. And uh and we mentioned South Africa earlier, and our most impressive mining operations are to be found in South Africa, specifically the Tawtona and Opponent mines, which have broken through around uh four kilometers or two point four five two point five miles of rock. So we're talking mines that are so deep that it takes an

hour to elevator down to the bottom. And you have to have a powerful, just an extremely powerful air conditioning system essentially like shoveling um ice down to the depths, because you have to balance out the hundred and thirty eight degree fahrenheit fifty nine degrees celsius temperatures in the surrounding rocks. Wow. So that's weird because I normally think of going down into a cave is uh something that that makes you nice and cool? I mean, I guess

unless it's like cold outside. I mean, one great thing about an underground environment is that it tends to have a pretty regulated temperature if you're at a certain depth. Right, this is the wine seller um uh situation. It's a place where you can keep a standard temperature for whatever you're storingly, but basement a wine seller is probably not going to go two and a half miles down into

the earth. Uh. By the way, with these minds, when we're talking about trying to balance out the temperatures, the air conditioning systems usually get temperatures uh back down to a more reasonable eighty two degrees fahrenheit twenty eight degrees celsius. So it's still hot. Yes, it's hot. Uh. These your dangerous places. The taw tone of mine today has some I read four miles or eight hundred kilometers of tunnels,

and it employs some fifty six thousand miners. And there are some whole books have been written about just the

scale of these mining operations and the like. The type of the technological details alone are pretty incredible, but then also the cultural asides about ghost miners, people who like sneak into the mines and what percentage of say gold, for for instance, is is pilfered, But then also how relatively little gold they have to actually mine out of the Earth to get a profit, because even though most of the gold on Earth we mostly don't do much

with it. It's it's it's extremely useful in in various electronics, but we're only using a fraction of that gold for those electronics. Per This is the rest we're wearing and looking at and and thing, oh isn't that sparkly and putting in a vault. Well, I'm interested in the idea of so that gold is down there where it's really hot, and you've got to pump in ice or air conditioning or something to keep you keep yourself from overheating while

you're trying to mind whatever the stuff is. And the question is why why does it get so hot when you go deep underground? I mean, we all know that it does get hot as you go towards the center of the earth, But why does that happen? Yeah, and I should point out to that we've known about this for a while. It was known even in medieval times.

Uh as mining efforts made it obvious that that, you know, they weren't going quite that deep, but they were still going deep enough to tell that things were getting warmer. And so, first of all, there's an incorrect answer to this question, and that is because you're getting closer and closer to Hell, and Hell is really hot, right, Well not if you're Dante. Right. Well, well that's true because well I guess there were hot parts and cold parts, yes,

but the very center was cold. When you get down to the lake local Itis, it is frozen solid for sure. So uh so yeah, I always fall back on Dante's model there, But the general idea is is Hell is hot and and so one could mistakenly think, Wow, he's gonna get hotter when you dig down to the Earth because you're getting closer to all of that. Uh that what heavy sweaty uh fiery brimstone. In fact, they're one

of my favorite art Bell clips out there. Art Bell but there was a Coast to Coast the old radio show where they often talked about ideas, Yeah, like late night paranormal conspiracy radio stuff. Yeah. One of the my favorite clips was about the Sounds of Hell, where they had this recording that was allegedly made via microphone which

was lowered into Hell via a hole in Siberia. Yeah, he got a note from a listener that, uh, he had already reported on the fact that geologists had drilled a hole to hell, and a listener got in touch with them and was like, hey, this story is true. My uncle collected videos and audio tapes to the paranormal and he had an audio tape of this and I copied it and it originally I think he said it came from the BBC or something, but that they had the evidence for hell and they were sitting on it.

And this is a great hoax story. This is part of the whole Well to Hell hoax that was reported over and over by tabloids and religious publications in the nineteen eighties and the nineties. Um, I've got a good quote here that is quoted in the Snopes article on this, on this hoax, But this quote came from a book in n Are You Ready, Robert, Let's do it? Okay. Geologists working somewhere in remote Siberia had drilled a hole some fourteen point four kilometers deep about nine miles when

the drill bits suddenly began to rotate wildly. A Mr. Asakov, identified as the project's manager, was quoted as saying they decided that the center of the Earth was hollow. Supposedly, the geologists measured temperatures of over two thousand degrees in the whole. They lowered supersensitive microphones to the bottom of the well, and to their astonishment, they heard the sounds

of thousands, perhaps millions, of suffering souls screaming. Uh so, according to Snopes, long before this ever appeared on The Art Bell Show, it was reported on the Christian station the known as Trinity Broadcasting Network. I think that still exists t N. I remember it. I don't know if it still exists. I think it does. What it was in nineteen eighty nine, they featured this story on tb N. It was also in the Weekly World News in nineteen two.

Is Weekly World News the one with bat Boy? I think it may have been, yes, but the Weekly World News version changed the location to Alaska and had the report ending with the claim that Satan himself came up out of the hole and the thirteen workers were killed in the incident, which, of course is basically the minds of Maria all over again. They're basically saying the dwarves got to then they do to. Yeah, but one of

the workers yelled, you shall not pass. I love it this story too, though, it's it's so ridiculous because it's like like, here is an example of science proving our religious ideas, proving our supernatural model as accurate. But did those people before this story literally think that hell was physically underground? It's just like a place you could go to if you dig that deep. I don't this would

be something worth exploring because I don't know. I don't get that that that sense a lot from older religious writing that that Hell is is literally in the ground. Um. I mean, I think there are some like if you go like to you know, the original like mythical texts and stuff, there's stuff like that, you know that heaven is literally physically in the sky, that the underworld is

literally physically under the ground. I don't. I didn't get the sense that many people believed that in the modern world, Like we're people aligned with TB and did they get this story and they're like, finally, you know, I knew there was something about this whole hell thing that didn't sit right with me. And it was like, well, I don't you know, if it's down there, we would have proof of it. Somebody would have drilled down there and recorded the sounds of the anguish. Well, people don't often

drill that deep as we'll discuss in a moment. So about the sounds of Hell. I don't know should we feature should we feature this recording at all on the podcast? Let's do it. Here's a taste, just a warning. It does sound really scary. It's like a it is made to sound scary. So it's a scary sound of people screaming.

Fair warning. So that sound clip, the sounds used in the Well to Hell hoax tape appear to be a Then people figured this out, a looped and reprocessed version of a clip from a movie called Barren Blood from nineteen seventy two. I looked it up and hey, it stars Joseph Cotton. Everything comes back to Joseph Cotton on this podcast. Is there a single topic that hasn't at

some point led us back to Joseph Cotton. He was in so many films from The Third Man in Citizen Kane, you know, classics of of of cinema from that era to uh stuff like Soilent Green uh and also various installments of euro horror, including one of my favorites, Screamers, The Island of the Fishmen. Uh. And yeah, just a lot of trashy like Gallo movies and and seventies junk. So, uh, Barren Blood. I haven't seen it. I was I wish I'd had time to watch it last night because it

looks like some some righteous trash um. But it was directed by Mario Bava. It has that grimy Mario Bava movie kind of look. And the Snopes right up traces the origin of this whole Well to Hell hoax to a hugely embellished take on reports in Scientific American published in nineteen four about a real drilling project called the Cola Super Deep Borehole, which we'll be back to in

a minute. So someone was literally like, well, they're digging that deep, they're gonna touch, they're gonna reach Hell, and then we're gonna hear about it. And then someone said, well, I'll just go ahead and make that. I just saw this movie called Baron Blood, which, by the way, you you shared the trailer clip with me, and I'm not a mistaken. The trailer itself has that, or at least a taste of that, the sound of Hell in it, screaming, screaming, going on. Yeah. I should also add they did not

in this story about the sounds from Hell. They didn't dig near deep enough to reach Hell. If Hell's at the center of the Earth, like they they didn't even maybe they reach like the outer the outskirts of a gigantic Hell. I mean, Earth would have to be so hollow for that, for like everything below like fourteen something point something kilometers down to be hollow. Yeah, and Earth

would then be mostly Hell, which is ridiculous. It maybe more befitting of like of a of a theology that really embrace and cherishes the idea of Hell is a vital aspect of its of its structure, like because that's the ugly reality. Great, you have a creation that's mostly people, sort tormented throughout all eternity, the thin layer of people sort of getting along on the surface. Uh. Great creation. Yeah, I mean I guess if you believe pretty much everybody

goes to Hell, Hell's got to be huge. But then how would how would Earth have a magnetosphere with a Hell this big? What's whereould the core dynamo effect come from? I have to look kind of answers in Genesis for that one show. Um, but but wait, we were asking a question. We got sidetracks talking about the well to Hell. No that we're asking a question about so we know that Earth actually does get hotter as you go deeper down into the ground. Why does that happen. It's not

because you're getting close to hell, but somehow it's getting hotter. Okay, so yeah, the the actual answer goes along these lines. So geologists calculate that for every mile you dig down, the temperature rises fifteen degrees fahrenheit and the pressure increases at a rate of seven thousand, three hundred pounds per square inch. Roughly go down deep enough and the temperature

and pressure is enough to form diamonds. Now, this is something that that learned minds noted, and uh one one in particular was Lord Kelvin, who lived through nineteen o seven, and he theorized that this was due to the cooling of the Earth and that that that he could use temperature readings to actually calculate the age of the Earth. We talked about this in our two episodes on the Edge of the Earth. We talked about Kelvin's attempts to

to gauge the age of the Earth this way. His he was sort of on the right track, but his calculations were off right. And so this is just a short version of this if you want the longer version, we advise you to listen to that episode to the age of the Earth thing is the two part. It wasn't it? It was so, But basically he thought, yeah,

twenty million years seems about right. He was wrong because one of the reasons that he didn't know about radioactivity in the Earth contributing to the heating to know about convection cycles and the inner layers of the Earth. So there are actually multiple reasons that Earth gets hotter the deeper you go down, right, and none of them are hell uh. So, there are three main sources for heat in the deep Earth. There's heat from when the planet

was formed and created. There's frictional heating caused by a denser core materials sinking to the center. And then there's heat from the decay of radioactive elements. And these causes are according to an Explainer article by Quentin Williams, who's a professor of Earth sciences, that you see Santa Cruz. So partially it's just always been hot since it was

ever formed, and it's been cooling off ever since. Partially there's like some rubbing going on down there that's causing some heat, and partially you've got like uranium and stuff that is decaying and given and that fission causes heat. But ultimately the Earth has this has this inner heat cycle that's going on, that's that's removed from the heat that comes from the sun. But you see that, I mean like the heat that comes from the sun as well.

I guess these are these are finite sources of heat, right, because if you've got some heat that's just left over from the formation of the Earth has been slowly cooling down, it will just keep cooling down until it gets colder and colder. Uh, the heat from the decay of radioactive elements. Eventually those things will pass their half life. They will just decay more and more until they reach stabile isotopes, though for some of them this will take a really

long time. Right. And we should also point out that the mysteries remain about the interior of the Earth that we don't know, that we don't fully understand. One of the ways that we we hope to increase our understanding is by drilling down into it. Now certainly not like sending people down to the mantle, but certainly, but by reaching the mantle, that alone would be an important step

towards better understanding the interior of the planet. Wait, are you telling me that that movie where they drill to the core is it called the Core? Is not scientifically accurate and not sending people down there pretty much. I love science fiction that has some sort of a fabulous drilling submarine that that takes people down into the depths, usually to some sort of interior hollow earth scenario. I love those films, but it's just not ultimately not realistic. Uh.

I like that movie. I haven't seen it. I feel like I should see it at some point because the dare you judge it without saying it? Well, the premise is so funny to me because it's like normally when you've got some kind of journey to the center of the earth that the Jewels Verne novel, that makes sense because it has incorrect ideas about what's down there under the surface. You know, there's another land and it can have creatures and all that, so there's like stuff to

do down there with the Core. I assume it just has a basically accurate idea that, like the Earth is made of rock and you know, solid material, so what's down there? They're going on an adventure just drilling into solid material. But where are the monsters? What's what's there to do? Yeah? Where are the bout the ball rocks? Right? I mean, I'd be happy to be surprised, but it's so anyway that the goal has been to drill down through roughly twenty five miles of crust to reach the mantle,

which makes up about the planet. One of the projects that had the same was the United States Project Mohole, which took a shot at in the late fifties and early sixties, but they lost their funding funding. They made it about five hundred and fifty seven feet down, and this was a sea floor drilling. But the more impressive one, the one that we referenced already, was the Cola Super

Deep but bore hole in Russia. So this one they managed to get down forty thousand, two hundred thirty ft or twelve thousand, two hundred sixty two meters uh, it's about seven point five miles. They did this over twenty years of drilling, and ultimately we're about halfway to the

mantle at this point. The effort was abandoned in the early nineties when they encountered higher temperatures than expected, though they were prepared for about two hundred and twelve degree farenheight temperature has been encountered three hundred and fifty six and uh, this is apparently still the record for how

far we've successfully successfully drilled down into our planet. And again that's the one that like at least some of the debunkers seemed to think that the idea of the well to Hell came from like there were stories about this.

So this was in nine four, I think or in the eighties, and then there were like articles about it in Scientific American and and I assume other publications, and that this probably got warped into the idea of the drilling and breaking through, right like if if Cola had actually hit Hell, that would mean Hell is in the crust of the Earth, is not even in the mantle. It' certainly not in the core. But you know, I'm gonna

I'll leave that alone for now. Other depoles of note, there's a BPS Deepwater Horizon which when it was operational made it down what thirty thousand feet or about five miles. Japanese drill ship Cheek you reached ten thousand feet or two miles into the sea floor, and they're actually aiming to go much deeper with that particular drill project, because they want to go even deeper and they they plan to break the record by around is when they look

to start drilling. So in the future we may see, uh, we may see an even higher figure on our descent. So maybe that's when we actually reach the lava men. Maybe so. But but then again, it would just be it wouldn't be us. It would be you know, the pro the sensor or something of that nature. I mean, it wouldn't be us at all, not not just because humans.

There's no reason for humans to go down right, as far as I can tell, the deepest humans have been in the Earth is probably two point five miles or four kilometers at the Opponent gold mine in South Africa. But that's deep. That's that's deep. I mean, it's still very impressive, but it's just it's such a small fraction when you start looking at the at the overall depths of the Earth. Alright, Well, on that note, we're gonna take one more break and when we come back, we're

gonna look to the future a little bit. Uh what else could humans do underneath the surface of this planet or another planet? Thank alright, we're back. Alright, So we're talking about underground dwelling humans making a habitat underneath the surface.

And one thing I think we've sort of touched on a little bit on the podcast before is space colonization becoming a route for us to become the lava men of other planets, to to to go down under the surface of another planet with Lord kin boat and set up residents there. Now, why would we do that? So other planets do not have all of the protections that Earth has from dangerous radiation. That's the main reason. Earth

has a thick atmosphere to absorb incoming radiation. It also has a magnetic field known as the magnetosphere, is created by the dynamo of its iron nickel core, and this magnetic field also repels incoming radiation. Other planets and objects in space do not have the same protective advantages. For example, the Moon and Mars. Mars does not have a core dynamo to produce a strong magnetic field to repel and

coming radiation. Also, Mars has a much much thinner atmosphere than Earth, less than one percent as thick as the Earth's atmosphere. So this just means when you're on the surface of Mars, there's a lot more radiation flux. The radiation is um is more variable, and you can get surges of it in different places and times, and it's just generally also much higher. So without these radiation shields, long term life on the surface of Mars for a colonist would be inconsistent. But in the net it would

be a high level radiation bath. Like levels seem to be such that you could probably survive there for a short period. It's not like you would just immediately die of radiation poisoning, but it would not be a good place to live long term for say, a permanent colony.

For example, to quote from a article by the space journalist Mike wall Quote, a mission consisting of a one eight day cruise to Mars, a five hundred day stay on the red planet, a one day return flight to Earth would expose astronauts to a cumulative radiation dose of about one point o one siverts measured by curiosities, radiation

assessment detector or rad instrument indicate. To put that in perspective, the European Space Agency generally limits its astronauts to a total career radiation dose of one cevert, which is associated with a five percent increase in lifetime fatal cancer risk. So that's just for a five hundred days stay on the surface. Now, of course, a lot of that radiation in that calculation there's coming from the trip to and from Mars. Where you're in space, you're gonna be getting

the most. Then once you get to Mars, there's some reduction because you've got the planet behind you. That helps, you know, but you're still getting a lot bombarded from space, way more than you would get protected on the surface of the Earth. So one solution here once you get to Mars is to go underground, where the soil and rock above will help protect the colonists from radiation if they're gonna be staying a long time. But you can think about this in a few Number one is like, Okay,

let's say you want to dig a deep hole. That would be kind of difficult because it's you know, you're on Mars. That's a lot of work to do. You have to bring literally everything with you. You have to bring your habitat, you have to bring your food, your air. Uh. And then on top of that you're talking about having to bring the equipment to dig tunnels in the Martian surface and create a space for all this stuff to go and for you to live. Yeah, like an excavator

or something like that. I mean that that's that's rough. So one proposed work around here is to establish colonist habitats in lava tubes. This has been proposed for Mars and for the Moon. Uh So, I put in a selection of images taken from satellite photos of things that look like openings to lava tubes on the surface of Mars. But I've got a really cool one. That's a photo from the High Resolution Imaging Science Experiment or high Rise camera,

which is on board the Mars Reconnaissance orbiter. I love this photo. It's very haunting. I believe this is taken from Pavonis Mons. But it's a crater, and then in the middle of the crater there's clearly just a hole where you can see the shadow and the light falling across an inner cavity down below, and you can even see what we're like, the sand from the crater is falling down into the hole. So these lava tubes would have been created because, of course Mars and the Moon

had periods of vulcanism in their past. The biggest volcano in the Solar System actually is not on Earth. It's not even on the yellow volcano hell World of Io, the moon of Jupiter. It's on Mars. Olympus Mons is the biggest volcano in the Solar System. It's a volcano more than twice as tall as Mount Everest. And so you can find these lava tubes on on Mars and the Moon, and they could be not only somewhat suitable to house uh colonies, they can they can in some

cases be huge. One example I found is that studies have shown the possible size of lava tubes on the surface of the Moon to be just enormous, like lunar lava tubes tend to be bigger than lava tubes on Earth. Based on leads and data from the Selene spacecraft and the Grail mission, researchers at Perdue University were able to predict that at least one lava tube near a group of volcanic domes on the Moon called the Marius Hills was at least large enough to to hold the entire

city of Philadelphia inside it. So space Philadelphia, We're space Rocky jogs this and maybe this is where the their their sports mascot is from. Was their sports mask. I don't think have any sports mascot. The frightening red one with no face. Oh yeah, the googly eyed pervert thing. Yeah yeah, I think that's their their icon. Oh that's a moon man. Yeah, but no, this is this isn't incredible The idea that these these are essentially just large caverns uh in in the planet or in this case,

that the lunar surface. Yeah, and I think this is it's because they are is because of the gravity of the Moon being different. I think that they can tend to be larger on the Moon than they usually are on Earth. This is comforting to anybody out there who is running Dungeons and Dragons campaign in the under dark, where you continually having adventures encounter large caverns with cities in them. You can just look to the lunar examples.

They will see here's here's how it might work. But so anyway, I like to think that our our future astronaut descendants who go out to colonize other objects in the Solar System, the ones who live on the Moon or live on live on Mars, might end up somehow being maybe culturally having some of the same environmental influences as the Neanderthals who made the rings of stalagmites deep down in the dark in southwestern France. Oh wow, that

is fascinating to think about. Like, what are the so you know, some of the underground religions are often referred to as like the idea of cathonic cults, you know, the cults of the underworld. Are are there certain ways that being in subterranean environments, are going into caves or into catacombs or whatever, tends to cause people to come up with certain cultural beliefs and religions. What are the religions of the lava tube dwellers look like? Who I love?

I love that idea? Um, you know, it would be remissing all of this if we didn't mention total recall though, because of course total recall, the original total recall, the Arnold total Recall in total, Yes, the the the Michael Ironside Total Recall. See you at the party rector exactly this one. This film features underground habitats, and it's revealed that the early stages of those underground habitats for early

colonists to Mars. They were essentially just caves that the people lived in um and and and that's and one of the curious things is that lines up with human history and also some of these models regarding what colonizing an off world habitat would consist of, and also teaches us not to put trust in caring for the resources of one of these off world colonies in the hands of a greedy, evil corporation. Overlord, give the people to air. Indeed,

give the people the air. Uh. Well, well, hopefully this is a good, you know, first installment. I want to think of this as a first installment on some perhaps deeper Earth and deeper life studies. Like I said, I'd like to come back and talk about the evolution of burrowing creatures, even if part of that is just a reason to talk about trimmers a little more. Uh, we could definitely have some more fun with the idea of of deep Earth religions and the idea and religious ideas

of the deep Earth. Yeah, there's a lot to explore here. Meanwhile, if you would like to dig deeper into stuff to blow your mind, head on't over to stuff to blow your mind dot com. That is that is the home world. That's where you will find all of the podcasts we recorded, going back to the very beginning to the very core of the planet. You'll also find links out to our

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