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Speaker 1: Imagine for a second that you're in the most pristine

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laboratory you can think of. You've got instruments that are just,

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you know, perfectly tuned to pick up the slightest vibration,

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a tremor, a crack, anything.

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Speaker 2: Right, the quietest room in the universe exactly.

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Speaker 1: Now, what if you decide to run the most powerful

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controlled experiment you can possibly imagine? You take a massive

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two and a half ton spacecraft and you deliberately crush

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it right into your subject.

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Speaker 2: Well, if that subject were Earth, you'd expect a pretty

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clear result. You'd get a big shockwave. Sure, it'd rattle

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a few size.

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Speaker 1: Mix stations, and then it would die down.

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Speaker 2: And then it would die down pretty quickly. Actually, yeah,

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our planet is just it's messy. It's full of heat

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and water and friction. It's really really good at dampening energy.

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It cracks, it settles, it moves on.

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Speaker 1: But the Moon, our ancient, silent neighbor, it did something

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completely different. It defied every single expectation. When NASA slammed

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the Apollo twelve lunar modulus sent stage into the This

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was November twentieth, nineteen sixty nine. The seismic event that

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followed didn't last for a few minutes even close. It

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just kept going for nearly an hour. It was this low,

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persistent hum that I'm sure both terrified and absolutely exhilarated

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the scientists back and mission control.

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Speaker 2: Oh for sure. And that one event, I mean, it

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produced this phrase that just it exploded. It became part

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of space history, but it also fueled five decades of

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conspiracy theory. Famous quote, famous quote. NASA reported that the

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moon rang like a bell. It didn't crack like a rock.

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It resonated like a musical instrument.

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Speaker 1: And that profound mystery, why did the moon ring? That's

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our mission today on the Deep Dive. We're going to

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go so much deeper than just that quote. We're going

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to investigate the origins of this this whole pseudo scientific

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spaceship moon hypothesis that the event launched.

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Speaker 2: And then we're going to use the hard data, the

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really hard one data from the Apollo seismic experiments all

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the way up to the super precise gravity map from

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the Grail mission, and.

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Speaker 1: We're going to reveal the actual complex and differentiated structure

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of our Moon, which it turns out, is a reality

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that is far stranger and honestly, far more fascinating than

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the fiction.

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Speaker 2: It really is. So it's time to settle the score.

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Is the Moon some kind of engineered artifact or is

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it just an extraordinary natural phenomenon. Let's dive deep into

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that seismic serenade.

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Speaker 1: So the Apollo program, I mean everyone remembers it for

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the human achievement for one giant leap, but it was

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also maybe even more importantly about laying the foundation for

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lunar geology.

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Speaker 2: Oh absolutely, we had to know what the Moon was

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made of, what was going on under the surface, and

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for that, Apollo twelve gave us the first and most

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critical setup.

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Speaker 1: That's right. So when the crew Pete Conrad and Alan

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Bean landed in the Ocean of Storms this is November

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sixty nine, a huge part of their mission on the

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surface was setting up the Apollo Lunar Surface Experiments package.

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And the centerpiece of that package, at least for our

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discussion today, is the Passive Seismic Experiment or PSC.

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Speaker 2: That's the one.

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Speaker 1: This thing wasn't just some off the shelf instrument they

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picked up, right, This was I mean bespoke, high precision

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engineering sent a quarter of a million miles from Earth.

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What exactly went into this unit.

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Speaker 2: It was serious hardware. It weighed about eleven point five

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kill grands or twenty five pounds, and it was housed

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in this specially designed thermally controlled box.

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Speaker 1: To protect it from the temperature swings exactly.

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Speaker 2: The lunar day and night cycle is just brutal. We're

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talking hundreds of degrees of difference, so it had to

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be protected. They used a lot of brilliant in its

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construction because it's super lightweight but also incredibly rigid. But

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the real genius, the real magic, was the sensor array itself.

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Speaker 1: Okay, so tell us about the sensors. What were they

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listening for.

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Speaker 2: The main goal was to map the inside of the moon,

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so they needed sensors they could hear, you know, both

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the quick, sharp things happening on the surface and the deep,

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slow groaning stresses.

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Speaker 1: From within a pretty wide range.

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Speaker 2: Wide range. So they had three matched long period seismometers

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LP seismometers.

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Speaker 1: And they were aligned how.

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Speaker 2: Orthogonally, so one vertical, two horizontal. These LPs were tuned

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to pick up very very slow moving waves, the kind

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of thing you'd get from say, deep moonquicks caused by

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the title pull from Earth or even you know, rumblings

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from the core and mantle.

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Speaker 1: So that's three sensors. What was the fourth one.

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Speaker 2: The fourth was a short period or SP seismometer. It

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was focused only on vertical movement, but it was sensitive

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to much higher frequencies up to twenty hertz.

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Speaker 1: And that one was for what surface impacts.

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Speaker 2: Exactly, meteoroid strikes, any kind of surface level tectonic event.

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The SP unit was vital for recording those. So in short,

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they had this incredibly comprehensive array designed to turn the

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entire Moon into a giant sensitive microphone.

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Speaker 1: Okay, so you have your giant microphone setup. Now you

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need to test it. You need a sound source. And

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this brings us to that famous event, the calibrated impact.

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It just sounds so reckless, crashing a piece of expensive

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hardware like that. But this was essential science, wasn't it.

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Speaker 2: It was absolutely crucial. Think about it. The scientists needed

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a known input. They needed to know the exact amount

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of kinetic energy delivered at a very specific point.

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Speaker 1: So they could measure how the waves traveled from that.

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Speaker 2: Point precisely to understand how the lunar crust transmits energy.

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I mean, you could just wait for a natural event

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like a random meteoroid impact. But that's that's haphazard. You

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don't know the mass, you don't know the velocity.

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Speaker 1: It's junk data, right, And it couldn't have been easy

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to guarantee the kind of precision you'd need to call

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a spent rocket stage a calibrated source. I mean they

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had to hit a specific spot to get the best

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readings for the seismometer.

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Speaker 2: The precision was just yeah, it was astonishing. It was

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a real testament to NASA's command of orbital mechanics at

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the time. They used the spent lunar module ascent stage.

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Speaker 1: So this is the part that carried Conrad and being

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back up from the surface to the command module.

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Speaker 2: That's the one They knew its exact mass down to

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the gram, and they could calculate its velocity at the

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moment of impact with incredible accuracy. For Apollo twelve, that

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LM hit the surface at a staggering six thousand, forty

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eight kilometers per hour.

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Speaker 1: Wow, let me just translate that. That is nearly three

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thy eight hundred miles per hour. That impact had some serious,

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serious power.

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Speaker 2: Oh yeah, it released energy equivalent to almost a ton

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of TNT. It blasted a crater that they estimated it

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was about nine meters or thirty feet wide. And here's

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the really crucial detail for the experiment, the location. The location.

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They managed to position the impact just one hundred and

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thirty five kilometers or about eighty four miles away from

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where the Apollo twelve sizic station was sitting.

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Speaker 1: Close enough for a really strong signal.

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Speaker 2: A strong, clear signal. That was the whole point.

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Speaker 1: So the planning is perfect, the instruments are running, the

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impact happens one hundred and thirty five kilometers away. What

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was the first sign that they had just hit something

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that was not a normal solid planet.

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Speaker 2: The data started streaming back and it was immediately obvious

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that something was fundamentally wrong or at least profoundly unique.

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How so well on Earth, when a major shockwave hits

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a seismometer, the seismogram spikes, You get this huge, sharp peak,

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and then the energy just decays really rapidly. Within a

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few minutes, maybe ten for a really massive earthquake, it's

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basically gone.

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Speaker 1: And the signal they got from the Moon.

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Speaker 2: Was the total opposite. It must have been absolutely riveting

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in Houston.

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Speaker 1: I can only imagine it was just surreal.

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Speaker 2: The signal didn't spike and then crash. It started small,

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it slowly grew in size to reach its peak amplitude,

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and then instead of dying, it just persisted for how long?

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The initial reverberation from that Apollo twelve LM impact lasted

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for over fifty five minutes, just shy of.

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Speaker 1: An hour an hour from one impact.

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Speaker 2: An hour, and some of the records from later larger

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impacts like the mighty Apollo thirteen SIVB Booster crash was

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a much bigger object. They suggested that the residual evaperations

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went on for over three hours.

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Speaker 1: Three hours of a low, continuous humming. That's what led

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to the legendary quote.

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Speaker 2: Right.

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Speaker 1: NASA scientists were reporting that even after an hour had passed,

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the smallest residual reverberations still hadn't completely stopped.

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Speaker 2: And that, you know, journalistically, led to the perfect analogy.

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The moon rang like a bell.

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Speaker 1: And we should be really clear here because this is

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where the misunderstanding starts. They didn't mean it made a

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sound like a church bell's tone, right.

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Speaker 2: It's about the physics, not acoustics. They meant that it's

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physical structure resonated, it sustained that elastic wave energy for

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a completely unprecedented amount of time. It was an extremely

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slow decay of a seismic signal.

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Speaker 1: A phenomenon that geophysicists call the seismic coda.

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Speaker 2: The seismic coda, Yeah, the long tail of the vibration.

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Speaker 1: So just to be one hundred percent clear for everyone listening,

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because this gets so twisted when we talk about ringing.

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We're talking about seismic waves, vibrations moving through rock. Right,

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there's no atmosphere, so you couldn't actually hear anything.

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Speaker 2: That's a vital distinction. Yeah, there's virtually no atmosphere, So

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acoustic waves sound as we know it, can't travel. An

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audible ding dong is completely out of the question.

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Speaker 1: But seismic waves are a form of sound.

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Speaker 2: They are they're longitudinal. In sheer waves, it's energy moving

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through solid material, which we detect as vibrations. So the

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ringing is just the perfect word to describe how those

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seismic waves are bouncing and reverberating all through the Moon's interior.

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It was acting more like a finely tuned, extremely rigid

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tuning fork than a damp composite rock like Earth.

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Speaker 1: Yeah, that makes sense. If you smash a piece of

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say dry, rigid glass, you might get a high frequency ping,

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but the energy dissipates really fast as it cracks, right,

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But if you hit a massive, solid, rigid iron sphere,

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it rings, it hums. The fact that the moon kept

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humming for nearly an hour that immediately suggested an underground

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structure that was fundamentally unlike anything we'd ever measured, and

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that difference, of course, is what led to all the speculation.

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Speaker 2: The moment that seismic data hit the public, especially when

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it was packaged with that incredibly dramatic ring like a

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bell analogy, it just created a vacuum, and it was

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a vacuum that was perfect for pseudoscientific theories.

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Speaker 1: Science had a genuine mystery on its hands, and the

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fringe theories had an explanation ready to go. The quote

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was everywhere. I remember seeing it in Popular Science magazine

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in early nineteen seventy and in the public imagination. The

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logic seems pretty simple. If a massive solid object resonates

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uniformly like that instead of just breaking.

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Speaker 2: And going silent, then it must not be solid.

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Speaker 1: It must be empty inside. It must be hollow, and.

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Speaker 2: That logical leap, as you put it, is the engine

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that drives the entire hollow moon hypothesis, and that very

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quickly evolved into the much more outlandish spaceship moon conjecture.

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Speaker 1: The timing here is just so key, isn't it. This

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is nineteen seventy We're at the absolute peak of the

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Cold War. The space race is still hot, We're constantly

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looking up wondering who's ahead.

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Speaker 2: And we're consuming massive amounts of science fiction. The idea

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of alien visitation was just it was in the air,

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it was normalized.

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Speaker 1: So this theory, the spaceship moon theory, it didn't actually

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originate in the US, did it.

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Speaker 2: No, Surprisingly, it came from the Soviet Union. In nineteen

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seventy two Soviet authors Michael Volsen and Alexander Shcherbakov. They

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published an article in Sputnik magazine.

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Speaker 1: It was just sort of like a Soviet international propaganda digest, that's.

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Speaker 2: A good way to put it. Yeah, And the title

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of the article was is the Moon the creation of

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alien intelligence?

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Speaker 1: Well, that leaves very little to the imagination. What was

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their central claim beyond just you know, the moon is hollow?

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Speaker 2: Their core thesis was that the Moon is an ancient artifact,

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a colossal spaceship or maybe some kind of observation satellite

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that was placed very precisely into Earth's orbit by an

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extremely advanced extraterrestrial civilization.

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Speaker 1: And the ringing was their proof.

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Speaker 2: The ringing was their proof of a massive manufactured outer

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shell surrounding a huge central void. They even tried to

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explain why it was there, suggesting it was some kind

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of long term observation post or a supply station.

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Speaker 1: But to make a theory like that compelling, you can't

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just rely on one weird seismic anecdote. They had to

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build a bigger case, and they did.

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Speaker 2: They were clever. They synthesized several known but slightly anomalous

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scientific observations about the Moon, and if you don't have

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the deep geophysical context, these points seem highly highly compelling.

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Speaker 1: So what were the main oddities they used to build

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their argument.

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Speaker 2: They leveraged four key points. The first one and the

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most critical for their argument, was the Moon's low bulk density.

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Speaker 1: Okay, let's just engage with the layman's logic here for

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a second. The Moon's average density is about three point

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three grams per cubic centimeter. Earth's average is five point.

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Speaker 2: Five a huge difference.

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Speaker 1: So why isn't that low number the ultimate smoking gun

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for emptiness? From their perspective, it seems obvious.

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Speaker 2: Well. Their argument is simple. If the Moon was formed

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from the same stuff as Earth, it should be much

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denser since it's so disproportionately light for its size. They

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argue that a massive internal emptiness avoid is the only

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way to account for the low mass.

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Speaker 1: And to a casual absord the math seems to check out.

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It suggests there's missing volume on the inside.

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Speaker 2: Right, And they're not wrong that the Moon is light

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compared to Earth. That difference is real and it does

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need explaining.

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Speaker 1: Okay, So that's point one. The second point they love

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to bring up was the cosmic coincidence of the perfect eclipse.

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This is probably the most emotionally appealing argument for a

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non scientist.

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Speaker 2: It's the ultimate piece of circumstantial evidence, isn't it. They

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cite the astronomical fact, and even a scientist is revered

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as Isaac Asimov called it a sheer astronomical accident that

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the Moon is precisely fourteen hundredth the size of the.

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Speaker 1: Sun and coincidentally it's also fourteen hundredth thus far away

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from us exactly, which means which means, during a total

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solar eclipse, the Moon perfectly snugly covers the Sun's disc.

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It's a mathematically perfect fit, and it's unique in our

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solar system.

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Speaker 2: And the theorists argue that for a body of the

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Moon's size to be at the exact orbital distance required

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to pull off this spectacular optical illusion, well, that suggests

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deliberate artific placement, not cosmic chance.

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Speaker 1: That's a classic argument from design. It implies control planning, which,

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if you're already thinking about alien intelligence, just seems to

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validate the whole theory.

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Speaker 2: Their third piece of so called evidence was more psychological.

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It played on human emotion and the sheer strangeness of

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this new frontier. They used astronaut anecdotes.

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Speaker 1: So things the Apollo cruse said.

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Speaker 2: Right, these astronauts were venturing into this stark, utterly unfamiliar world,

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and they often used very evocative language to describe it.

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Neil Armstrong called it magnificent desolation. Buzz Aldrin once mentioned

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that the lunar surface had a strange mechanical feel under

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the landing struts of the eagle.

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Speaker 1: Ah. I see. So the emotional poetic descriptions of astronauts

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experiencing a completely alien environment were taken literally stripped of

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all contexts.

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Speaker 2: Yeah, they were repurposed as circumstantial proof that they were

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walking on a manufactured, engineered structure. Any mention of the

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Moon being unnatural or alien was treated as hard evidence

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of an artifact, And the.

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Speaker 1: Final pillar of their argument was the compositional anomalies. This

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ties back to the whole idea of an engineered outer shell.

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Speaker 2: This is where they brought in the armour plating idea.

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The basalt rocks brought back by the Apollo missions at

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surprisingly high concentrations of titanium, often in a mineral called ilmanite.

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Speaker 1: And titanium is incredibly strong and heat resistant exactly.

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Speaker 2: So the proponents of the theory suggested that this was

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evidence of an artificial metal rich outer layer, a protective

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hull designed to withstand cosmic debris and extreme heat, just

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like a battleship is armored.

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Speaker 1: So when you put it all together, it's a pretty

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compelling story. You start with a mysterious noise, you layer

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in some genuinely unusual data points, little density, perfect eclipses,

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and you wrap it all up with the story of

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alien engineers. It's better than most science fiction, and.

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Speaker 2: That connection to science fiction is so important. Decades before

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Vasen and Scherbakoff, you had H. G. Wells writing about

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the Selenites living inside a.

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Speaker 1: Hollow moon right in the First Men in the Moon.

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Speaker 2: And then later writers like Edgar Reice Burrows and more

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recently David Weber. They all played with the idea of

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a manufactured or inhabited moon. The popular imagination was already

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primed and ready to accept the idea that our closest

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companion could be an intentional creation.

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Speaker 1: But I think the time has come to shift from

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that captivating narrative of fiction and speculation back to the rigorous,

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sometimes messy reality of planetary science, because the real explanation

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for why that bell rang is far more intricate and

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frankly way cooler than any alien spaceship.

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Speaker 2: I agree, the scientific explanation for that prolonged reverberation is

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one of the most elegant takedowns of a conspiracy theory

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00:16:41,519 --> 00:16:43,559
that I know of. The moon didn't ring because it

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was hollow. It rang because it is an almost perfectly

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preserved and natural object with two very unique characteristics, extreme

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dryness and extreme fracturing.

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Speaker 1: Okay, let's start with the dryness and how that affects

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energy loss. We need to talk about seismic wave attenuation

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and something called the quality factor or CUE.

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Speaker 2: Right. So, attenuation is basically a measure of how quickly

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seismic wave energy is loss converted into heat as the

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wave travels through a material. It's like internal friction. Okay,

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and the quality factor Q is just the number we

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use to quantify this damping. A low Q factor means

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high energy loss, the wave dies out vast. A high

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Q factor means very low energy loss. The wave forssists

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for a long time.

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Speaker 1: So why does Earth have such a low coup factor?

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Why does our planet silence itself so quickly?

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Speaker 2: Because Earth is hot, it's dynamic, and most importantly, it's wet.

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Water and other volatile compounds like innhydrated minerals. They act

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as incredibly effective.

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Speaker 1: Damping agents, like a shock absorber.

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Speaker 2: It's exactly like a shock absorber. Think of the difference

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between hitting a damp sponge versus hitting a dry piece

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of ceramic. The internal friction that's generated when seismic waves

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push through water or through regions of partial melt in

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the upper mantle, it just dissipates the energy very, very rapidly.

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That's why our seismic code only lasts for a few minutes.

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Speaker 1: And the Moon, the early reports from NASA described it

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as being incredibly rigid, like a piece of dry stone.

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Speaker 2: The Moon is the polar opposite of Earth in this respect,

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bone dry. It's almost entirely free of water and other

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volatile compounds below the surface. It's also relatively cool and

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very rigid throughout its shallow.

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Speaker 1: Depths, So all those things that act like shock absorbers

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here they just aren't there.

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Speaker 2: They're just not there. This almost total lack of internal

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damping agents means that seismic energy is conserved with phenomenal efficiency.

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The Moon has an exceptionally high Q factor we estimated

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to be as high as five thousand in the upper mantle,

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and on Earth, the Earth's crustal Q factors rarely get

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above a few hundred, so it's a massive difference.

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Speaker 1: So the energy is conserved so well that once you

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pump it in, it just doesn't have a way to

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die out quickly. That explains the duration of the signal exactly.

383
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Speaker 2: That explains why the Moon doesn't absorb the energy. But

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that rigidity and dryness alone, that doesn't explain the complexity

385
00:18:55,920 --> 00:19:00,319
of that hour long, slowly peaking signal. For that, you

386
00:19:00,400 --> 00:19:04,680
need the second key factor, which is extreme scattering and heterogogeneity.

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Speaker 1: Okay, and this is where the relentless pounding the Moon

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has taken for billions of years comes into play. You're

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talking about the megaregolith.

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Speaker 2: The megaregolis is absolutely vital to this whole process. See.

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Unlike Earth, where tectonic activity and erosion are constantly smoothing

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out and recycling the surface, the Moon has basically preserved

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a record of every single major impact for four point

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00:19:25,920 --> 00:19:27,160
five billion years.

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Speaker 1: So it's just been shattered over and over again.

396
00:19:29,359 --> 00:19:31,400
Speaker 2: Over and over and this has resulted in a really

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00:19:31,480 --> 00:19:33,960
deep layer the crust and the upper mantle down to

398
00:19:34,000 --> 00:19:38,559
maybe two hundred kilometers. That is a highly fractured, heterogeneous structure.

399
00:19:38,799 --> 00:19:42,720
It's a jumble of shattered bedrock, broken and re welded rock,

400
00:19:43,000 --> 00:19:44,920
and fine dust a regulith.

401
00:19:45,160 --> 00:19:48,759
Speaker 1: So it's not a uniform solid structure at all. It's

402
00:19:48,799 --> 00:19:53,319
an almost unbelievably complex mash of different rocks with random

403
00:19:53,400 --> 00:19:56,359
variations in density and composition at every turn.

404
00:19:56,599 --> 00:19:59,960
Speaker 2: It is the ultimate scattering medium. Imagine you launch a

405
00:20:00,039 --> 00:20:04,359
billiard ball across a perfectly smooth table. It follows a nice, straight,

406
00:20:04,599 --> 00:20:07,680
predictable path. That's sort of what seismic waves do on

407
00:20:07,720 --> 00:20:10,279
Earth for the most part. Now, imagine putting that same

408
00:20:10,359 --> 00:20:13,680
billiard ball into a giant box that's filled with thousands

409
00:20:14,000 --> 00:20:18,240
of irregularly shaped hard objects. It's going to bounce everywhere.

410
00:20:18,680 --> 00:20:20,039
That's the Moon's megaregulith.

411
00:20:20,119 --> 00:20:23,079
Speaker 1: It's like the energy gets trapped in a seismic pinball machine.

412
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Speaker 2: That is a perfect analogy, or you could think of

413
00:20:25,720 --> 00:20:29,160
it as a vast hall of mirrors. For seismic waves.

414
00:20:30,000 --> 00:20:33,400
The energy, which we've already established is being conserved really well.

415
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Instead of following a short direct path from the impact

416
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of the sensor.

417
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Speaker 1: It just bounces off everything.

418
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Speaker 2: It's continuously reflected, trapped, and diffused throughout the entire medium.

419
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The ways end up taking these myriad, long, winding indirect

420
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paths to the seismometer, and all those different path lengths

421
00:20:52,440 --> 00:20:55,559
arriving at different times exponentially stretches out the time it

422
00:20:55,599 --> 00:20:57,640
takes for the entire signal to decay.

423
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Speaker 1: And that gives you the prolonged seismic that lasts for hours.

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Speaker 2: That's exactly right, and this is why in geophysics we

425
00:21:04,000 --> 00:21:07,559
have to talk about single versus multiple scattering theory. Oh wait,

426
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explain that on Earth. Because the high attenuation kills the

427
00:21:10,720 --> 00:21:13,359
wave so quickly, we can generally get away with using

428
00:21:13,400 --> 00:21:16,559
single scattering theory. We assume the energy travels more or

429
00:21:16,640 --> 00:21:19,240
less directly, maybe hits one or two boundaries, and then

430
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it dies simple. On the Moon, the waves are scattered

431
00:21:23,279 --> 00:21:26,440
so intensely and their energies can serve so well that

432
00:21:26,480 --> 00:21:29,440
you have to model it using multiple scattering or diffusion theory.

433
00:21:30,200 --> 00:21:33,759
The energy literally diffuses throughout the Moon's near surface volume,

434
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almost like light diffusing through thick fog or a glass

435
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of milk.

436
00:21:37,640 --> 00:21:40,839
Speaker 1: So the complex persistent signal, the very evidence that was

437
00:21:40,880 --> 00:21:44,480
cited to prove the Moon is a smooth, uniform engineered shell,

438
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is actually the perfect acoustic signature of an ancient, fractured, messy,

439
00:21:50,160 --> 00:21:52,519
and extremely dry natural world.

440
00:21:52,799 --> 00:21:56,039
Speaker 2: It's the ultimate irony of the ringing like a bell quote,

441
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isn't it?

442
00:21:56,480 --> 00:21:59,079
Speaker 1: It really is. It proves the exact opposite of what

443
00:21:59,079 --> 00:22:00,559
the theory claims it does.

444
00:22:00,599 --> 00:22:04,359
Speaker 2: It captures the imagination perfectly. But the detailed science tells

445
00:22:04,440 --> 00:22:07,799
us that if the Moon were an engineered artifact, say

446
00:22:07,839 --> 00:22:11,279
a smooth, homogeneous metal sphere, it would probably produce a

447
00:22:11,400 --> 00:22:14,759
very clean, simple, high frequency tone that decayed very quickly

448
00:22:14,839 --> 00:22:19,119
like a tuning fork. The messy complex prolonged decay that

449
00:22:19,279 --> 00:22:21,079
is the signature of natural complexity.

450
00:22:21,119 --> 00:22:24,119
Speaker 1: So even with that really elegant explanation of low attenuation

451
00:22:24,200 --> 00:22:27,440
and diffusion scattering, we still have to definitively knock down

452
00:22:27,480 --> 00:22:30,160
the other cornerstones of the spaceship moon theory, and the

453
00:22:30,160 --> 00:22:31,720
big one is the claim that the Moon is just

454
00:22:31,799 --> 00:22:34,079
too light to be solid, that it must contain a

455
00:22:34,119 --> 00:22:34,839
massive void.

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00:22:35,039 --> 00:22:38,319
Speaker 2: Right, and this is where the concept of planetary differentiation

457
00:22:38,440 --> 00:22:44,279
and especially modern gravitational mapping provides the final definitive physical refutation.

458
00:22:45,880 --> 00:22:48,319
We can now confirm that the Moon is a fully

459
00:22:48,359 --> 00:22:54,119
differentiated solid body with a complex layered interior, a crust,

460
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a mantle, and a dense core.

461
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Speaker 1: And this structure formed billions.

462
00:22:58,160 --> 00:23:01,039
Speaker 2: Of years ago, about four point five billionyears. Yeah, long

463
00:23:01,079 --> 00:23:03,880
before any potential alien engineers would have shown up on

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the scene.

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Speaker 1: Okay, so let's tackle that density issue head on. Why

466
00:23:06,759 --> 00:23:09,279
is the low bulk density of three point three grams

467
00:23:09,279 --> 00:23:11,319
per cubic centimeter not proof that.

468
00:23:11,279 --> 00:23:14,519
Speaker 2: It's hollow, because that number is entirely consistent with the

469
00:23:14,599 --> 00:23:16,680
leading theory of how the Moon formed in the first place,

470
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the giant impact hypothesis or GIH.

471
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Speaker 1: This is the idea that a Mars sized object, which

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00:23:22,960 --> 00:23:26,000
we sometimes call THEA, slammed into the very early Earth.

473
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Speaker 2: That's the one The GIH posits that the Moon formed

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from the debris that was flung out into orbit after

475
00:23:31,000 --> 00:23:33,519
that cataclysmic collision. But the crucial detail here is the

476
00:23:33,519 --> 00:23:35,319
state of the proto Earth before it got hit.

477
00:23:35,680 --> 00:23:37,480
Speaker 1: It had already started to differentiate.

478
00:23:37,799 --> 00:23:41,599
Speaker 2: Exactly by the time THEA struck Earth had already undergone

479
00:23:41,640 --> 00:23:46,480
significant differentiation. Most of Earth's dense metallic iron, which is

480
00:23:46,480 --> 00:23:49,200
the stuff that makes our planet's average density so high

481
00:23:49,519 --> 00:23:52,720
at five point five, had already sunk down and segregated

482
00:23:52,759 --> 00:23:53,519
into its core.

483
00:23:53,960 --> 00:23:57,119
Speaker 1: So when the impact happened and blasted all that material

484
00:23:57,200 --> 00:23:58,640
out into space, that.

485
00:23:58,519 --> 00:24:02,359
Speaker 2: Material came primarily from Earth's iron depleted rocky mantle and

486
00:24:02,400 --> 00:24:05,759
from the impactor itself. So the cloud of debris that

487
00:24:05,839 --> 00:24:09,880
eventually coalesced to form the Moon was naturally inherently iron

488
00:24:09,920 --> 00:24:11,160
pore from the very beginning.

489
00:24:11,240 --> 00:24:14,119
Speaker 1: So the Moon is light because of its birth circumstances,

490
00:24:14,160 --> 00:24:15,480
not because it's a hollow shell.

491
00:24:15,599 --> 00:24:19,960
Speaker 2: Precisely, that single point completely eliminates the fundamental need to

492
00:24:20,000 --> 00:24:23,480
invent a giant vacuum cavity to explain the low density.

493
00:24:23,759 --> 00:24:25,799
Speaker 1: But the proof that the Moon is solid comes from

494
00:24:25,839 --> 00:24:28,480
deep inside. Let's go back to the Apollo seismic data

495
00:24:28,480 --> 00:24:30,680
for a minute. What do the moonquakes tell us about

496
00:24:30,720 --> 00:24:31,160
the mantle?

497
00:24:31,559 --> 00:24:34,799
Speaker 2: The Apollo passive seismic experiments, which it's amazing to remember,

498
00:24:35,119 --> 00:24:37,359
ran all the way until nineteen seventy seven.

499
00:24:37,200 --> 00:24:40,000
Speaker 1: Wow, for years after the last astronauts left for.

500
00:24:40,079 --> 00:24:44,839
Speaker 2: Years, and they provided conclusive proof of a massive solid mantle.

501
00:24:45,720 --> 00:24:49,680
They recorded thousands of deep moonquakes. These things were originating

502
00:24:49,720 --> 00:24:52,759
between seven hundred and one thousand kilometers below the surface.

503
00:24:52,839 --> 00:24:54,200
Speaker 1: And what causes those.

504
00:24:54,319 --> 00:24:57,559
Speaker 2: The tidal stresses exerted by Earth's gravity. As the Moon

505
00:24:57,680 --> 00:25:01,480
orbits us, it's constantly being squad eased and stretched.

506
00:25:01,200 --> 00:25:04,920
Speaker 1: One thousand kilometers deep. That is a huge distance for

507
00:25:04,920 --> 00:25:07,440
a seismic wave to have to travel to reach the surface.

508
00:25:07,559 --> 00:25:10,839
Speaker 2: It's massive, and the fact that the seismic waves generated

509
00:25:10,880 --> 00:25:14,279
by these deep quakes can propagate hundreds and hundreds of

510
00:25:14,319 --> 00:25:18,119
kilometers upward through the tholid mantle and still be detected

511
00:25:18,119 --> 00:25:21,839
by the instruments on the surface. That conclusively proves the

512
00:25:21,839 --> 00:25:25,680
physical existence of a massive solid medium occupying all that

513
00:25:25,759 --> 00:25:26,720
volume below the crust.

514
00:25:26,799 --> 00:25:28,480
Speaker 1: So there's no way it's a hollow shell just under

515
00:25:28,480 --> 00:25:28,960
the surface.

516
00:25:29,039 --> 00:25:32,039
Speaker 2: No way the internal void, if it existed, would have

517
00:25:32,119 --> 00:25:34,839
to start at best way down near the very center

518
00:25:34,880 --> 00:25:35,240
of the Moon.

519
00:25:35,359 --> 00:25:37,319
Speaker 1: And now we get to the really definitive proof of

520
00:25:37,319 --> 00:25:40,079
that central mass. This is thanks to modern data and

521
00:25:40,119 --> 00:25:42,240
a concept called the moment of inertia or mo.

522
00:25:42,640 --> 00:25:45,559
Speaker 2: The moment of inertia is maybe the most powerful tool

523
00:25:45,640 --> 00:25:49,279
of planetary geophysicists has because it tells you exactly how

524
00:25:49,279 --> 00:25:51,960
the mass is distributed inside a rotating body.

525
00:25:52,039 --> 00:25:53,400
Speaker 1: And how do we measure it.

526
00:25:53,440 --> 00:25:56,319
Speaker 2: For the Moon, we calculate it by observing the Moon's

527
00:25:56,319 --> 00:25:59,680
gravity field with extreme precision and by watching how it's

528
00:25:59,680 --> 00:26:03,680
slightly wobbles or libraids in its orbit. That data has

529
00:26:03,720 --> 00:26:07,839
been refined for decades by the lunar laser ranging experiments.

530
00:26:07,240 --> 00:26:10,440
Speaker 1: Where they bounce lasers off the reflectors the Apollo astronauts

531
00:26:10,480 --> 00:26:11,359
left behind.

532
00:26:11,119 --> 00:26:14,000
Speaker 2: That's right, and that gives us these incredibly precise measurements.

533
00:26:14,319 --> 00:26:17,599
Speaker 1: So what are the theoretical benchmarks for MOI? How does

534
00:26:17,640 --> 00:26:19,640
it tell us if something is hollow or solid?

535
00:26:19,960 --> 00:26:22,680
Speaker 2: Okay? So think of it like this. A perfectly hollow

536
00:26:22,759 --> 00:26:25,400
sphere with all of its mass concentrated right on the

537
00:26:25,440 --> 00:26:28,240
outer rim, would have an AMI factor of point sixty seven.

538
00:26:28,400 --> 00:26:29,680
Speaker 1: Okay, high number for hollow.

539
00:26:29,759 --> 00:26:32,960
Speaker 2: A body with perfectly uniform density all the way through,

540
00:26:33,240 --> 00:26:36,119
like a solid, undifferentiated ball of rock, would have an

541
00:26:36,119 --> 00:26:38,960
AMOY of point four lower. And if a body has

542
00:26:38,960 --> 00:26:42,240
a dense core and a lighter exterior, like all differentiated

543
00:26:42,599 --> 00:26:45,440
worlds do, its MOY factor has to be less than

544
00:26:45,480 --> 00:26:48,799
point four because more of the mass is concentrated at

545
00:26:48,839 --> 00:26:49,759
the center of rotation.

546
00:26:50,279 --> 00:26:53,599
Speaker 1: So the big question where does the moon land?

547
00:26:53,759 --> 00:26:57,039
Speaker 2: The modern data derived from decades of laser ranging and

548
00:26:57,079 --> 00:27:00,400
the incredibly precise measurements from the geomission can strains the

549
00:27:00,440 --> 00:27:03,200
Moon's MOY factor two point three ninety four plus or

550
00:27:03,200 --> 00:27:04,720
minus point zero zero.

551
00:27:04,480 --> 00:27:07,400
Speaker 1: Two point three nine four. Okay, So that is exceptionally

552
00:27:07,440 --> 00:27:09,640
close to the uniform density number of ono point four.

553
00:27:09,680 --> 00:27:11,960
Speaker 2: It's very close, yeah, which tells us the Moon's density

554
00:27:12,039 --> 00:27:14,519
gradient isn't super steep, but critically it.

555
00:27:14,480 --> 00:27:17,720
Speaker 1: Is lower, and that small deviation is everything.

556
00:27:17,920 --> 00:27:20,359
Speaker 2: It is everything. The fact that the MOI is less

557
00:27:20,400 --> 00:27:23,599
than point four is definitive physical proof that the mass

558
00:27:23,680 --> 00:27:26,640
is concentrated towards the center. It confirms that the Moon

559
00:27:26,720 --> 00:27:29,240
is not only not hollow, which would require a point

560
00:27:29,319 --> 00:27:32,240
sixty seven, but it is a fully differentiated body with

561
00:27:32,319 --> 00:27:36,079
a denser core than its surrounding material. That single highly

562
00:27:36,079 --> 00:27:39,440
precise number just completely destroys the hollow hypothesis.

563
00:27:39,599 --> 00:27:41,839
Speaker 1: So we've established the Moon must have a dense center.

564
00:27:42,039 --> 00:27:44,720
But the absolute final nail in the coffin comes from

565
00:27:44,720 --> 00:27:48,160
the g RAIL mission, the Gravity Recovery and Interior Laboratory.

566
00:27:48,200 --> 00:27:50,200
This is what allowed us to actually map the structure

567
00:27:50,240 --> 00:27:50,720
of that core.

568
00:27:51,039 --> 00:27:55,000
Speaker 2: Dreil was a masterpiece of Geodyssy flew from twenty eleven

569
00:27:55,039 --> 00:27:58,680
to twenty twelve. It was two identical spacecraft flying in

570
00:27:58,720 --> 00:28:01,640
this tight tandem format orbiting the Moon, and.

571
00:28:01,640 --> 00:28:04,480
Speaker 1: They were measuring the distance between each other constantly.

572
00:28:04,759 --> 00:28:08,039
Speaker 2: They measured the minute changes in distance between them caused

573
00:28:08,039 --> 00:28:11,279
by subtle variations in the Moon's gravity on the surface below.

574
00:28:11,640 --> 00:28:14,119
When the lead satellite passed over an area of higher

575
00:28:14,119 --> 00:28:18,319
mass concentration, you would be pulled forward slightly, increasing the distance,

576
00:28:18,880 --> 00:28:21,079
and they could measure that change down to the micrometer.

577
00:28:21,240 --> 00:28:23,680
Speaker 1: That's insane. And that data allowed them to build the

578
00:28:23,680 --> 00:28:26,759
most accurate gravity map of the Moon ever conceived by far.

579
00:28:27,519 --> 00:28:29,400
Speaker 2: And this map, when you combine it with a re

580
00:28:29,519 --> 00:28:33,160
analysis of all that old Apollo seismic data, it finally

581
00:28:33,200 --> 00:28:35,799
allowed scientists to peel back the layers and see exactly

582
00:28:35,839 --> 00:28:37,440
what's down there in that central space.

583
00:28:37,559 --> 00:28:38,640
Speaker 1: So what do they find.

584
00:28:38,720 --> 00:28:43,680
Speaker 2: They confirmed a distinct, multilayered core and it entirely occupies

585
00:28:43,720 --> 00:28:47,359
the space that the void Hyposteris claims is empty. At

586
00:28:47,359 --> 00:28:50,519
the very center, there's a solid inner core made of

587
00:28:50,640 --> 00:28:53,599
pure iron, extending out to a radius of about two

588
00:28:53,680 --> 00:28:54,839
hundred and forty kilometers.

589
00:28:54,880 --> 00:28:56,440
Speaker 1: And round that solid core.

590
00:28:56,599 --> 00:29:00,200
Speaker 2: Surrounding that is a liquid outer core. This is made

591
00:29:00,200 --> 00:29:03,519
of molten iron alloy, probably mixed with some lighter elements

592
00:29:03,519 --> 00:29:06,920
like sulfur and nickel. And this liquid core extends out

593
00:29:06,920 --> 00:29:09,559
to a radius of about four hundred and eighty kilometers

594
00:29:09,599 --> 00:29:13,039
and it's dense, very dense, around five grams per cubic centimeter.

595
00:29:13,240 --> 00:29:16,960
Speaker 1: Structure is huge a radius of four hundred and eighty kilometers.

596
00:29:17,440 --> 00:29:20,559
That means the core occupies about twenty percent of the

597
00:29:20,559 --> 00:29:21,960
Moon's entire diameter.

598
00:29:22,119 --> 00:29:22,440
Speaker 2: It does.

599
00:29:22,680 --> 00:29:26,440
Speaker 1: You absolutely cannot have a solid, high density iron core

600
00:29:26,519 --> 00:29:29,680
and a massive liquid iron outer core and still pretend

601
00:29:29,680 --> 00:29:32,400
there's a giant vacuum cavity in there. The space is

602
00:29:32,440 --> 00:29:33,480
physically occupied.

603
00:29:33,559 --> 00:29:36,559
Speaker 2: And what's more, the existence of those distinct layers was

604
00:29:36,599 --> 00:29:40,160
confirmed by a really sophisticated reanalysis of the original Apollo

605
00:29:40,200 --> 00:29:43,680
moonquake data, specifically by observing how different types of seismic

606
00:29:43,720 --> 00:29:45,480
waves behaved as they pass through the center.

607
00:29:45,680 --> 00:29:47,920
Speaker 1: Okay, tell us how they can distinguish between solid and

608
00:29:47,920 --> 00:29:49,519
liquid just by using waves.

609
00:29:50,119 --> 00:29:52,079
Speaker 2: Well, they are two main types of seismic body waves.

610
00:29:52,079 --> 00:29:55,039
You have P waves, which are compressional waves, and S waves,

611
00:29:55,119 --> 00:29:57,680
which are sheer waves. TA waves can travel through both

612
00:29:57,759 --> 00:30:02,119
solid and liquid MATERIALS wave, however, physically cannot propagate through

613
00:30:02,119 --> 00:30:03,759
a liquid They just stopped debt.

614
00:30:03,920 --> 00:30:07,039
Speaker 1: So if they recorded P waves traveling all the way

615
00:30:07,079 --> 00:30:09,440
through the center, but they saw S waves disappearing at

616
00:30:09,440 --> 00:30:13,559
a specific radius, they've just mapped the boundary between the

617
00:30:13,599 --> 00:30:15,400
solid mantle and the liquid core.

618
00:30:15,559 --> 00:30:18,319
Speaker 2: That's exactly it. The researchers were able to map the

619
00:30:18,359 --> 00:30:22,000
Moon's core boundaries with precision by tracing the S wave

620
00:30:22,119 --> 00:30:25,400
shadow the region where S waves cease to be transmitted.

621
00:30:25,559 --> 00:30:29,160
This is fundamental geophysical evidence. It proves the existence of

622
00:30:29,200 --> 00:30:33,680
a high density molten outer core surrounding an even denser

623
00:30:33,920 --> 00:30:37,640
solid inner core. No amount of wishful thinking can erase

624
00:30:37,680 --> 00:30:38,759
that physical reality.

625
00:30:39,000 --> 00:30:41,480
Speaker 1: Okay, so let's just quickly address that last piece of

626
00:30:41,519 --> 00:30:46,160
circumstantial evidence. The conspiracy theorists used the high titanium rocks.

627
00:30:46,319 --> 00:30:48,440
Why isn't that a sign of artificial armour plating.

628
00:30:48,640 --> 00:30:52,000
Speaker 2: The high concentration of titanium mainly in that mineral ilmanite

629
00:30:52,039 --> 00:30:55,559
is explained entirely by a natural but incredibly dramatic geological

630
00:30:55,640 --> 00:30:57,160
process called mantle overturn.

631
00:30:57,319 --> 00:30:59,920
Speaker 1: And this happened very early in the Moon's history.

632
00:31:00,240 --> 00:31:04,000
Speaker 2: Early around four point two billion years ago, right after

633
00:31:04,000 --> 00:31:08,079
the global magma ocean had mostly solidified. As that magma

634
00:31:08,119 --> 00:31:12,160
ocean crystallized, some of the last materials to solidify included

635
00:31:12,440 --> 00:31:15,079
these really dense minerals like ilmanite.

636
00:31:15,160 --> 00:31:16,640
Speaker 1: So they formed a layer near the top.

637
00:31:16,759 --> 00:31:18,640
Speaker 2: They formed a layer in the uppit part of the mantle.

638
00:31:18,720 --> 00:31:22,400
But here's the dramatic part. This layer of dense ilmanite

639
00:31:22,480 --> 00:31:25,519
rich rock was sitting on top of less dense material

640
00:31:25,599 --> 00:31:28,920
underneath it. It was gravitationally unstable, like.

641
00:31:28,920 --> 00:31:31,400
Speaker 1: Having an ocean where the heavier water is somehow floating

642
00:31:31,440 --> 00:31:32,640
on top of the lighter water.

643
00:31:32,759 --> 00:31:35,759
Speaker 2: Perfect analogy. It couldn't last, so the Moon in a

644
00:31:35,759 --> 00:31:39,720
way literally turned itself inside out. Wow, that dense ilminite

645
00:31:39,839 --> 00:31:43,400
rich layer began to sink and overturn, causing this enormous

646
00:31:43,480 --> 00:31:46,440
vertical mixing within the mantle, and Grail's gravity maps actually

647
00:31:46,480 --> 00:31:50,720
confirmed this. They revealed these long linear anomalies, vast submerged

648
00:31:50,759 --> 00:31:54,319
features that are the geological scars of this sinking material

649
00:31:54,359 --> 00:31:55,559
as it cascaded downward.

650
00:31:55,759 --> 00:31:58,920
Speaker 1: So that complex natural process accounts for all the compositional

651
00:31:58,920 --> 00:32:00,319
weirdness they found.

652
00:32:00,240 --> 00:32:02,920
Speaker 2: Every bit of it. It completely eliminates the need for

653
00:32:02,960 --> 00:32:06,160
an engineered hull. And plus we know the crust itself

654
00:32:06,240 --> 00:32:09,039
is highly asymmetrical. It's much thinner on the near side

655
00:32:09,039 --> 00:32:11,559
facing us and thicker on the far side. That kind

656
00:32:11,559 --> 00:32:15,279
of irregularity is the signature of a messy natural evolution,

657
00:32:15,480 --> 00:32:20,119
not uniform engineering. The geophysical evidence for a solid, internally

658
00:32:20,200 --> 00:32:23,400
dynamic moon is just it's.

659
00:32:23,279 --> 00:32:26,920
Speaker 1: Overwhelming, So we can pretty confidently conclude that the Moon's

660
00:32:27,039 --> 00:32:30,000
famous ringing wasn't the sound of a holospace ship.

661
00:32:29,960 --> 00:32:33,119
Speaker 2: Not at all. It was the extraordinary acoustic signature of

662
00:32:33,160 --> 00:32:38,480
a natural, highly rigid, and extremely fractured solid world. The

663
00:32:38,559 --> 00:32:42,079
sound persists because there's almost no friction to dampen the energy.

664
00:32:41,880 --> 00:32:44,440
Speaker 1: And the signal is so complex because that energy gets

665
00:32:44,559 --> 00:32:47,359
trapped and bounced around in that deep layer of shattered rock.

666
00:32:47,559 --> 00:32:50,440
Speaker 2: The core takeaway here really is that the scientific truth,

667
00:32:50,480 --> 00:32:53,480
based on the hi Q factor diffusion scattering and the

668
00:32:53,480 --> 00:32:57,400
definitive gravitational proof of a dense, multi layered iron core,

669
00:32:57,920 --> 00:32:59,640
is just so much more complex and so much more

670
00:32:59,640 --> 00:33:02,319
compelling than the simple idea of alien engineering.

671
00:33:02,599 --> 00:33:06,079
Speaker 1: And refuting the hollow moon theory doesn't make the Moon boring,

672
00:33:06,880 --> 00:33:10,160
not by a long shot. It still holds these profound,

673
00:33:10,599 --> 00:33:14,920
real world mysteries that are driving the entire next generation

674
00:33:15,160 --> 00:33:16,440
of space exploration.

675
00:33:16,799 --> 00:33:19,079
Speaker 2: I think that's the most exciting part. While the deep

676
00:33:19,119 --> 00:33:21,759
structure is solid, we're now finding that the crust is

677
00:33:21,839 --> 00:33:25,720
full of natural voids that could be absolutely crucial for

678
00:33:25,799 --> 00:33:27,160
a future human habitat.

679
00:33:27,200 --> 00:33:29,039
Speaker 1: You're talking about the lava tubes.

680
00:33:28,839 --> 00:33:32,200
Speaker 2: The collapse lava tubes. Yeah, recent high resolution images have

681
00:33:32,319 --> 00:33:36,079
confirmed these natural lunar pits and caves, especially in regions

682
00:33:36,119 --> 00:33:38,720
like the Sea of Tranquility. Some of them are huge.

683
00:33:38,839 --> 00:33:41,759
We're talking eighty meters long and forty five meters wide.

684
00:33:41,799 --> 00:33:44,400
Speaker 1: And why are these natural voids so important for something

685
00:33:44,440 --> 00:33:45,759
like the Artemis program.

686
00:33:45,839 --> 00:33:49,279
Speaker 2: They are critical because they offer natural shielding. Inside those

687
00:33:49,359 --> 00:33:52,359
lava tubes, the temperatures are stable. They hover around a

688
00:33:52,359 --> 00:33:54,599
relatively comfortable minus twenty degrees.

689
00:33:54,400 --> 00:33:57,599
Speaker 1: Celsius compared to the extreme three hundred degree swing on

690
00:33:57,640 --> 00:33:59,000
the surface exactly.

691
00:33:59,119 --> 00:34:02,079
Speaker 2: But even more importantly, they would shield future astronauts and

692
00:34:02,119 --> 00:34:06,440
their equipment from the constant rain of micrometeoroid impacts and

693
00:34:06,480 --> 00:34:10,239
from the lethal doses of solar and cosmic radiation. So

694
00:34:10,400 --> 00:34:12,880
we might not be living in some alien bunker.

695
00:34:12,679 --> 00:34:16,320
Speaker 1: But we could be settling in these ancient natural geological

696
00:34:16,360 --> 00:34:17,440
bunkers precisely.

697
00:34:17,960 --> 00:34:21,320
Speaker 2: It's amazing to think that the same geological complexity that

698
00:34:21,440 --> 00:34:25,880
gave us the titanium anomalies and the asymmetrical crust also

699
00:34:25,960 --> 00:34:29,079
created the perfect natural shelters for humanity's return.

700
00:34:29,320 --> 00:34:31,800
Speaker 1: And even with all this incredible data from the Apollo

701
00:34:31,800 --> 00:34:35,239
seismometers running for eight years, to the beautiful gravity maps

702
00:34:35,239 --> 00:34:38,760
from geoplanetary scientists still describe our understanding of the Moon's

703
00:34:38,760 --> 00:34:41,599
deep interior as being well rudimentary.

704
00:34:41,880 --> 00:34:45,159
Speaker 2: It's true the fine details of that mantle overturned the

705
00:34:45,239 --> 00:34:48,400
exact composition of the inner core. There's still so much

706
00:34:48,440 --> 00:34:51,320
to learn. The Artemis program is planning to deploy new

707
00:34:51,360 --> 00:34:55,360
seismic instruments like the Farcite Seismic Suite to refine our models.

708
00:34:55,440 --> 00:34:57,800
The story of how the Moon became so lopsided is

709
00:34:57,840 --> 00:34:59,639
still being written deep below the surface.

710
00:35:00,119 --> 00:35:03,800
Speaker 1: So we've definitively established why the Moon rings. It's the

711
00:35:03,840 --> 00:35:08,480
sound of conserved energy in a dry, highly fractured solid world.

712
00:35:08,639 --> 00:35:11,760
That the emotional power of that original quote rang like

713
00:35:11,800 --> 00:35:14,960
a bell. It allowed the spaceship Moon theory to persist

714
00:35:15,000 --> 00:35:18,320
for decades. It just goes to show how easily a

715
00:35:18,360 --> 00:35:21,920
poetic phrase can supersede complex science in the popular mind.

716
00:35:22,239 --> 00:35:26,519
Speaker 2: It really speaks to our profound, very human desire for mystery.

717
00:35:27,000 --> 00:35:29,360
Speaker 1: So we'll leave you with this thought to ponder. We

718
00:35:29,400 --> 00:35:32,000
know the scientific facts. We know exactly why the Moon

719
00:35:32,039 --> 00:35:35,159
really rang, thanks to the immense rigor of panetary science,

720
00:35:35,639 --> 00:35:38,239
But even knowing the physics of the low density and

721
00:35:38,280 --> 00:35:42,159
the MUAI confirmation. What soundgiving detail about the Moon. Maybe

722
00:35:42,199 --> 00:35:45,800
it's the sheer astronomical coincidence of that perfect solar eclipse,

723
00:35:46,199 --> 00:35:49,280
or the incredible scale of that ancient mantle overturn. What

724
00:35:49,400 --> 00:35:51,880
detail still makes you pause and wonder if our closest

725
00:35:51,920 --> 00:35:54,199
neighbor is still stranger than we can fully grasp.

726
00:35:54,440 --> 00:35:56,280
Speaker 2: Let us know your thoughts in the comments. We're back

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00:35:56,320 --> 00:35:57,639
next time for another deep dive