Cosmic Connections: Uranus's New Moon, Rogue Planets, and the Devil Comet's Water Mystery

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Anna: Hello and welcome to Astronomy Daily,

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your daily guide to the cosmos, where we.

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Avery: Explore the latest breakthroughs and biggest stories from

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the world of space and astronomy. I'm Avery.

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Anna: And I'm Anna. It's great to have you with us.

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We have an absolutely stellar lineup for you

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today.

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Avery: We certainly do. We'll be visiting the distant

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ice giant Uranus, which has a brand new

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moon. We'll also be exploring the lonely lives of

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rogue planets, which it turns out might not

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be so lonely after a.

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Anna: Tale of two sibling asteroids that could hold clues

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to the origin of life. And we'll be

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chasing the famous Devil Comet to find out if

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it's responsible for the water in our oceans.

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Avery: It's a packed show, so let's jump right in.

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Anna: Our first story takes us out to the seventh planet

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from the sun. The solar system's family

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portrait has a new addition as astronomers have

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officially confirmed the discovery of a new

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moon orbiting Uranus.

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Avery: That is fantastic news. It feels like the outer

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planets are the final frontier of our own solar system.

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It's amazing to think we're still finding new members out

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there. What do we know about this newcomer?

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Anna: Well, for one thing, it's incredibly small.

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Current estimates put its diameter, uh, at just five

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miles, or about eight kilometres. That makes it

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a strong contender for the title of smallest of

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Uranus's now 28 known moons.

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Avery: Five miles, that's miniscule on a planetary

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scale. To put that in perspective, that's shorter than

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running a 10k race. How on Earth did they even

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spot something so tiny so far away?

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Anna: With a very powerful telescope and

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a lot of patience. The discovery was made using the

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Magellan telescopes at the Las Campanas

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Observatory in Chile. The first sighting

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was on November 4, 2023.

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But it took further observations to confirm its

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orbit and officially announce it on

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February20.

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Avery: And it's been given one of those classic catchy

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astronomer names, I assume.

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Anna: Of course, for now, it's carrying the temporary

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designation S 2023

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U1. It will likely get a more permanent

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name later, traditionally from the works of

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Shakespeare or Alexander Pope. In keeping with

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Uranus's other moons.

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Avery: I'll be waiting to see if it becomes a Juliet or a

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Puck. I also read that its orbit is

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huge. It takes 680 days to

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circle Uranus. That's a long year for such a tiny

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moon.

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Anna: It is indeed. And this find is significant

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because it's the first new Uranian

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moon discovered in more than 20 years. It

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really underscores how much we still have to learn about

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the ice Giants. They're distant, dim

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and difficult to study from Earth.

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Avery: It makes you wonder what else is hiding out there in the dark.

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A tiny body like this was probably a captured

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object from the Kuiper Belt, wasn't it? A visitor

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that got a little too close and was pulled into orbit?

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Anna: That's the leading theory. Its distant

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eccentric orbit suggests it wasn't formed from

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the same disc of material as Uranus's

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larger inner moons. It's a relic from the early

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solar system, now a permanent part of

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Uranus's family.

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Avery: Well, from a captured moon to entire

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systems without a sun.

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Our next story is a real mind bender. It's about

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rogue planets and the astonishing possibility that

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they can form their own moons.

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Anna: This is truly a revolutionary idea,

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backed by some stunning observations from the James

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Webb Space Telescope. For our listeners.

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Rogue planets, or as they're officially called,

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free floating planetary mass objects, are

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worlds that drift through interstellar space

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completely untethered from any star.

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Avery: We used to imagine them as cold, dark and

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solitary objects, but this new research

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suggests that they might be the centre of their own little solar

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systems. JWST observed eight of

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these rogue planets in the nearby Orion Nebula.

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Anna: And it didn't just see the planets themselves.

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It saw that they were surrounded by discs of

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gas and dust. What's more, the

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telescope's instruments detected the chemical signature

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of crystalline silicates within these discs.

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Avery: And that's important because.

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Anna: Because that's the very same material we

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see in the protoplanetary discs around

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young stars. It's the raw material that

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clumps together to form planets, moons

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and asteroids. Finding it around a

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rogue planet is a huge surprise.

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Avery: Uh, so you're saying these starless planets

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have their own proto moon discs,

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that they're basically acting like miniature suns,

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gravitationally gathering material to build their own

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satellite systems?

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Anna: That's exactly what the evidence points to.

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These discs could and likely will

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coalesce into moons and perhaps even

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ring systems, all orbiting a planet

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that has no star. It creates a whole

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new class of celestial object, a

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rogue planetary system.

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Avery: Wow. That fundamentally challenges our

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models of system formation. We've always put

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a star at the heart of that process. The

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star's gravity and energy were thought to be essential.

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Anna: It seems the fundamental physics of accretion might

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be more universal than we thought.

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Gravity is the key ingredient and it

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seems a, uh, planet sized object has enough of

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it to start building a family of its own.

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The galaxy could be teeming with these dark

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wandering systems, completely

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invisible to us until now.

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Avery: From lonely wanderers. Let's come Back closer to

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home for a story about family.

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Two of the most famous asteroids in recent memory,

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Ryugu and Bennu, have been confirmed

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to be siblings.

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Anna: This is the payoff for two of the most

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ambitious sample return missions ever

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attempted. Japan's Hayabusa 2

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mission visited Ryugu and NASA's

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Osiris Rex mission visited Bennu. Both

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successfully brought back pristine samples.

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And now we're seeing the incredible result.

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Avery: Uh, and the results are conclusive. By analysing

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the composition of the return samples,

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scientists have confirmed that both of these carbon

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rich top shaped asteroids are

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fragments of the same much larger parent body.

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Anna: So somewhere long ago, a, uh, giant

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asteroid got hit by something else in a

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catastrophic collision and shattered. And

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Ryugu and Bennu are two of the pieces that went

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flying.

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Avery: Precisely. The mineralogy and chemical

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makeup are just too similar for it to be a

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coincidence. But what's really exciting

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isn't just that they're related, but what they're

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made of. This is where it gets really interesting for us

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here on Earth, right?

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Anna: Absolutely. Both samples are rich

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in water bearing clay minerals. That tells us

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their parent body once had a lot of water

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ice. And even more importantly, they

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are packed with a wide variety of organic

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molecules.

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Avery: Amino, um, acids, the building blocks of proteins.

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The very stuff of life.

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Anna: Exactly. This discovery provides

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powerful support for the hypothesis that

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asteroids and comets acted as a

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cosmic delivery service for the early Earth.

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They could have delivered both the water for our

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oceans and the complex organic compounds

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necessary to kickstart life.

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Avery: So when we look at these two sibling asteroids, we could

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be looking at the same type of object

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that gave Earth its starter kit for life.

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It's like finding the delivery truck that brought the

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ingredients for the first ever cake.

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Anna: That's a great analogy. It

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reinforces the idea that the ingredients for

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life aren't necessarily rare or unique

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to Earth, but are widespread throughout the

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solar system, just waiting for the right conditions.

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Avery: Well, speaking of that cosmic delivery service,

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our final story today zooms in on

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one very specific delivery truck, the

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Devil Comet. And it's carrying a very

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precious cargo.

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Anna: Yes, the Comet, officially named 12

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P. Pons Brooks, has been putting

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on quite a show for astrophotographers.

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But for planetary scientists, the real show

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is what's inside the water vapour it's

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releasing as it nears the sun.

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Avery: Using incredibly sensitive instruments like the

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Atacama Large Millimetre Sub Millimetre

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Array, or ALMA, and

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NASA's Infrared Telescope Facility,

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researchers have been able to analyse that water.

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And they found what many have been searching for

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for decades.

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Anna: They have the water in Comet

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Pons Brooks has an isotopic

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signature that is a near perfect

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match for the water here on Earth.

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Avery: Okay, let's break that down. An

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isotopic signature is like a chemical

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fingerprint. Right. It's about the different

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flavours of hydrogen atoms in the water molecules.

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Anna: That's a good way to put it. Specifically,

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scientists measure the ratio of

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deuterium, a heavy version of hydrogen,

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to normal hydrogen. This is

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known as the D to H ratio.

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For a long time, the comets we were able to

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measure had much higher D to H AH

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ratio than Earth's oceans, which made

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the cometary delivery theory a bit

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shaky.

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Avery: Right. The fingerprints didn't match, so

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scientists started looking more towards asteroids as

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the primary water source.

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Anna: Exactly. But this new measurement from

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Pons Brooks changes the story. It's a

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Halley type comet originating from the

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icy Oort Cloud. And. And its water is

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virtually indistinguishable from ours.

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The fingerprint is a match.

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Avery: So this single comet provides the strongest

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evidence yet that its ancient relatives are the

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reason we have oceans. Billions of years ago,

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a relentless bombardment of comets like Pons

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Brooks could have painted our dry, rocky

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planet blue.

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Anna: It makes the cometary origin of Earth's

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water a leading theory. Once again, it

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doesn't mean asteroids didn't contribute.

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It was likely a combination of both.

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But this is a huge piece of the puzzle.

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Avery: It's incredible to think about. Every time you have a

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glass of water, you might be drinking the remnants of

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ancient comets that travelled for billions of

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years across the solar system. That's a, uh, truly

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cosmic connection.

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Anna: And what a profound thought to end on.

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That's all the time we have for today on Astronomy

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Daily. We've journeyed from a new moon

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around Uranus to the very origins

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of the water on our own planet.

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Avery: It's been another day of incredible discoveries that remind

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us just how dynamic and interconnected the

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universe is. Thank you so much for joining us.

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Anna: For more details on all today's stories and

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links to the original research, be sure

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to visit our

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website@astronomydaily.IO

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we'll be back tomorrow with more of the latest

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news from across the cosmos. Until

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then, I'm Anna.

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Avery: And I'm Avery. Keep looking up