Cosmic Tug-of-War, Mars Orbiter's Stellar Capture, and Black Hole Anomalies

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Avery: Welcome to Astronomy Daily, the podcast that

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brings you the universe one story at a

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time. I'm avery. Give us 10 minutes and

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we'll give you the universe.

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Anna: And I'm, um, Anna. It's great to be with you.

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Avery: Today we're talking about the ultimate fate

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of the universe. Is its expansion slowing

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down. We'll also check in on a Mars orbiter

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that's been moonlighting as an interstellar

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photographer and and get an update on.

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Anna: A scrubbed launch, plus a baffling

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record breaking flare from a distant black

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hole. And a fascinating new paper that

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asks, could alien probes already be

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in our solar system?

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Avery: It's a lot to cover, so let's jump right

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in.

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Anna, start us off with this universe

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altering news.

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Anna: Let's do it. The main headline is that our

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universe's expansion might be slowing down.

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This feels counterintuitive to what we've

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understood for decades.

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Avery: It really does.

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Anna: For a long time, the standard model of

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cosmology, which we call lambda cdm,

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has been built on the idea that the

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universe's expansion is accelerating, driven

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by a mysterious force called dark energy.

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Avery: Right, the cosmological constant, the

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lambda in lambda cdm.

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Anna: Exactly. It's been treated as a constant,

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unchanging force pushing everything apart.

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But new research analyzing data from various

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cosmic probes and telescopes suggests that

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that dark energy might not be constant at

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all. It might be evolving and even

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weakening over time.

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Avery: Evolving? What does that mean for a

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fundamental force of the universe?

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Anna: It means that dark energy could be something

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more dynamic, what some physicists call

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quintessence. Instead of being a static

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property of spacetime, it could be a field

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that changes over cosmic history. This new

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evidence suggests its repulsive force might

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be decaying.

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Avery: Wow. So if the outward push is getting

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weaker, what happens then?

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Anna: Well, that's the most dramatic part of this

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story. If dark energy continues to weaken,

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the fundamental force of gravity, which is

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always pulling inward, could eventually win

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the cosmic tug of war.

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Avery: And that leads to the Big Crunch?

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Anna: Potentially, yes. Instead of expanding

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forever into a cold, dark big freeze,

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the the universe's expansion would slow,

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halt, and then reverse.

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Galaxies would start rushing back towards

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each other, eventually collapsing into an

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incredibly hot, dense singularity.

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Much like the state before the Big Bang.

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Avery: It's a mind bending possibility. So is the

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Big Crunch our new official destiny?

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Anna: Not just yet. This research is still

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challenging the prevailing model, and a lot

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more data is needed to confirm it. But it's a

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huge development that has cosmologists and

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everywhere buzzing. It just reminds us that

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the universe is still full of Profound

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mysteries.

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Avery: Absolutely.

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Well, let's pull our focus from the edge of

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the universe back into our own solar system.

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China's Tianwan 1 orbiter has sent back

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some incredible new images.

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Anna: That's right. While its primary mission at

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Mars is complete, Tianwen1 is in an

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extended mission phase. And it has

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accomplished something remarkable. It managed

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to capture detailed images of an interstellar

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object known as 3i Atlas.

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Avery: An interstellar object. So a visitor from

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another solar system like Oumuamua.

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Anna: Precisely. These objects are incredibly

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rare and difficult to observe. Getting high

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resolution images of one from a spacecraft

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already in deep space is a major

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technical achievement. It gives us a close up

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look at a building block from another solar

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system.

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Avery: What can we learn from it?

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Anna: The data helps us understand its composition,

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shape and rotation, which tells us about the

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conditions in the planetary system wherein

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formed. It's also fantastic

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practice. Practice for what? For their

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next big mission, Pianwen 2. That

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mission is designed to visit a near Earth

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asteroid, collect samples and return them to

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Earth. Successfully tracking and imaging

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a fast moving distant object like

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3i ATLAS proves their

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capabilities and provides valuable data for

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planning that ambitious sacrifice sample

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return mission.

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Avery: Very cool.

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Now for a quick update from the launch pad.

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It was a no go for United Launch alliance

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yesterday.

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Anna: Yes, unfortunately the much anticipated

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launch of their Atlas V rocket carrying the

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Viasat 3F2 satellite was

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scrubbed.

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Avery: They called it off late in the countdown. Any

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word on what the issue was?

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Anna: The official reason cited was an issue with

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ground systems equipment. These are complex

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machines and safety is paramount. These. The

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good news is they've already rescheduled the

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launch for the following day.

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Avery: Fingers crossed for a successful liftoff.

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This is an important satellite, right?

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Anna: It is. It's the second of three satellites in

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a constellation designed to provide high

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speed, affordable broadband Internet service

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to most of the globe. So we'll be watching

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closely and wishing them the best on the next

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attempt.

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Avery: Alright, From a launch delay back to the deep

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cosmos, this next story sounds like a real

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head scratcher for astronomers. A

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supermassive black hole has unleashed a flare

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of epic proportions.

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Anna: It really is a puzzle. This flare

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spotted by the Zwicky Transient Facility

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or ztf, is not just bright.

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It's the longest lasting flare we've ever

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seen from a supermassive black hole. It has

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been going on for years and shows no signs of

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stopping.

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Avery: Years? I thought these things were usually,

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well, transient. And that's what the TNZTF

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stands for, right?

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Anna: Exactly. Usually when a star gets too

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close to a supermassive black hol torn

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apart in what we call a tidal disruption

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event that causes a flare that typically

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lasts for a few weeks or months. This event

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is on a completely different timescale.

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Avery: So what do they think is causing it?

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Anna: That's the mystery. The leading theory is

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that it's an exceptionally massive star,

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perhaps a hundred times the mass of our own

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sun, that has been captured and is slowly

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being consumed. But even that doesn't fully

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explain the flare's duration and steady

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brightness.

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Avery: It must be an incredible opportunity for

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research, though.

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Anna: An unprecedented one. Because this black

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hole is so distant, we're seeing it as it was

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in the very early universe. Studying this

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long slow meal gives us a unique window

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into how supermassive black holes grow

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and affect their host galaxies in the cosmic

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dawn.

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Avery: From one mind bending topic to another. Our

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final story sounds like pure science fiction,

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but it's being discussed in a serious

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scientific paper. Are we talking about alien

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probes?

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Anna: We are. Specifically, the paper

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discusses the concept of von Neumann probes.

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These are theoretical self replicating

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robotic probes that could be sent to explore

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a, uh, galaxy.

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Avery: Self replicating? So one probe arrives in a

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new star system, uses local resources to

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build copies of itself, and then those copies

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travel to other star systems?

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Anna: That's the idea. It's an incredibly efficient

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way to explore the vastness of the Milky Way

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on a timescale of millions of years, rather

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than billions. Billions. The new paper makes

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a bold suggestion that if an advanced

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civilization has ever created such probes,

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they could already be here in our own

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solar system.

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Avery: Okay, wow. So where should we be

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looking?

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Anna: The paper proposes we should be actively

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searching for their technosignatures,

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evidence of their technology. And it singles

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out a prime location for the search. Our

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Moon. Why the Moon? Because it's

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a stable, geologically dead world. A

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probe could land there, use lunar resources

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to replicate, and its artifacts could remain

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undisturbed for hundreds of millions of

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years. Unlike Earth, there's no weather or

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geological activity to erase the evidence.

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Avery: So we should be scanning the high resolution

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images we have of the lunar surface for

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anything out of place.

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Anna: Exactly. It's a long shot, of course,

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but the authors argue it's a, uh, search

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worth conducting. Finding even a

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single non terrestrial artifact on the

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Moon would be one of the most profound

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discoveries in human history.

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Avery: And what a profound thought to end on. From

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the fate of the universe and interstellar

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visitors to bizarre black holes and the

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possibility of ancient alien technology on

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our doorstep. What a day in Astronomy.

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Anna: It certainly shows that there is always

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something new to discover, no matter where we

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look. Thanks for joining us today on

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Astronomy Daily.

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Avery: We'll be back tomorrow with more news from

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across the cosmos. Until then, be sure to

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subscribe wherever you get your podcasts so

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you never miss an episode. Clear Skies