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Avery: Welcome to Astronomy Daily, the podcast that

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brings you the universe one story at a time.

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I'm your host, Avery.

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Anna: And I'm your co host, Anna. It's great

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to be with you all again, Avery.

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Here in the northern hemisphere, it feels

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like the nights are really drawing in.

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Getting colder, darker.

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Avery: They certainly are. But that darkness

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isn't always a bad thing, especially when it

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becomes a canvas for some of the universe's

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most incredible art. And we're starting

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today's show with just that.

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Anna: That's right. We have a packed episode

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from spectacular atmospheric light shows

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right here at home to the ultimate

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fate of Earth itself.

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Avery: And we'll also look at potential threats from

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outside our solar system, find a beacon of

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hope on an icy moon, and preview an exciting

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new mission to Mars. So let's get right to

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it.

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Anna: I'm ready if you are.

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Avery: Alrighty. Our first story is a visual

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feast for anyone lucky enough to be in the

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right place at the right time. Between

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November 5th and 8th, 2025, the night

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sky put on a show for the ages. A

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powerful geomagnetic storm triggered stunning

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auroras.

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Anna: It really was something special. This was

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classified as a G3 class storm on the

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five point scale, which is considered strong.

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It was all thanks to a significant coronal

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mass ejection, or cme, that

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erupted from the Sun a few days prior.

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Avery: Right. A, uh, cme. Um, so basically the sun

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threw a massive blob of plasma and

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magnetic field our way.

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Anna: Exactly. When that wave of charged

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particles hits our magnetosphere, it

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channels them towards the poles. They rain

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down into our upper atmosphere, collide with

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air molecules, and energize them, causing

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them to glow. The. The beautiful greens are

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from oxygen, while rarer pinks and

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reds come from nitrogen.

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Avery: And this storm was powerful enough that the

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lights were seen much farther south than

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usual. We saw incredible photos and time

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lapses from the northern United States, the

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UK, and all across Scandinavia. It must

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have been just breathtaking to see in person.

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Anna: It truly is an experience that connects you

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to the cosmos. It's a vivid, dynamic

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reminder that we live inside the atmosphere

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of a star.

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Avery: It's.

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Anna: And that our sun is an active, powerful

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force. We're currently in an active period

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of the solar cycle, so we might get a few

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more shows like this in the coming years.

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Avery: I certainly hope so. A, uh, beautiful event

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and a great way to start our cosmic journey

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today.

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Anna: From the beautiful effects of our star's

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activity to a more sobering look at its

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eventual demise.

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Our next story comes from NASA's Transiting

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Exoplanet Survey Satellite, which or TESS.

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And it paints a stark picture of the fate of

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planets orbiting sun like stars.

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Avery: Ah, uh, tess. Its main job is hunting for

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exoplanets. But it's great at just watching

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stars. What did it see this time?

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Anna: It was watching older stars, those beginning

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to enter their red giant phase. And the new

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study confirms that these swelling stars are

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engulfing their inner planets far more often

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than some models predicted. They the evidence

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is in the starlight itself. They can detect

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the chemical signatures of planetary material

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being consumed by the star.

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Avery: Consumed? That's a gentle word for it.

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It's more like being vaporized and

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eaten.

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Anna: A very accurate description. As a star

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like our sun exhausts hydrogen fuel in its

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core, it starts burning it in a shell, which

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causes its outer layers to expand enormously

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and it can swell to hundreds of times its

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original size.

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Avery: And um, any planets in the way.

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Anna: Any planets in the way are first subjected to

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immense tidal forces that can tear them

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apart. And then they are swallowed by the

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star's expanding atmosphere, the

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photosphere.

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Avery: Which brings us to the big scary.

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What does this mean for Mercury, Venus and

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us, uh, here on Earth?

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Anna: Well, Mercury and Venus are almost

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certainly doomed. As for Earth, the

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picture is now looking grimmer. While some

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models suggested Earth's orbit might widen

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and save us, this new data suggests

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the Sun's expansion will be too aggressive to

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overcome that shift.

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Avery: It does. But let's not forget this is about

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5 billion years in the future. So there's no

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need to sell your stocks just yet.

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Anna: Exactly. But it's a profound look into the

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celestial mechanics that govern the birth and

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death of worlds. It gives us a real sense of

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cosmic perspective. Our planet has an

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expiration date written in the stars.

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Avery: Okay. From a threat 5 billion years

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away to one that is, well, less

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predictable. A fascinating new piece of

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research is helping us understand the risk of

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impacts from interstellar objects

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or ISOs.

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Anna: These are the cosmic nomads. Objects like

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asteroids and comets that have been ejected

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from their own star systems and are now

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wandering the Milky Way.

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Avery: That's them. Um, we've had three famous

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visitors so far that we know of. The strange

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cigar shaped Oumuamua in 2017

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and the more comet like Borisov in

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2019. Then there's the current one

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everyone's talking about. 3i

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Atlas those three flybys prove that these

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objects are out there.

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Anna: Right. And now we want to know how many more

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there are and what the chances are that one

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might hit us.

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Avery: Precisely. This new study tells us where

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we're most likely to see them coming from the

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solar apex. That's the direction our

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solar system is traveling as we orbit the

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galaxy. It's what's in front of our cosmic

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windshield, so to speak.

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Anna: So we're essentially running into a stream of

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these objects as we travel through the

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galaxy.

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Avery: It does. The study also pointed to the

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galactic plane as another likely source.

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Now, to be clear, the researchers stress that

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the probability of an impact on from a large

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ISO remains extremely low.

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There's just a lot of empty space out there.

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But for planetary defense experts, this is

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crucial information. It tells them where to

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prioritize their search efforts. It's about

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being smart and looking in the right

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direction for these very faint, very fast

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moving objects.

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Anna: So it's another step towards creating a

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comprehensive map of potential hazards both

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from within and without our solar system.

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Fascinating stuff.

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Avery: Alright, let's leave the threats behind and

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travel to Saturn's icy moon

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Enceladus. It's getting more promising in the

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search for extraterrestrial life, thanks to

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a fresh look at old data from the

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Cassini mission.

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Anna: It absolutely is. Cassini orbited

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Saturn from 2004 to 2017,

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and scientists are still making incredible

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discoveries from its data archives. The big

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news we've known for years is the South Pole

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with its Deimos tiger stripe fissures that

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blast plumes of water from a subsurface ocean

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into space.

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Avery: Yeah, an underground ocean of

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liquid water. That m alone is amazing.

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Anna: It is. But the North Pole was always

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considered the boring one. Frozen,

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ancient and inactive. Well, by

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reanalyzing thermal data from Cassini's

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flybys, scientists have now discovered a

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significant heat signature coming from the

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North Pole as well. The ice is much thicker

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there, so it was trapping the heat, but it's

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definitely there.

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Avery: Wow. So the moon's internal engine is

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heating it at both poles. What does that

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imply for the ocean?

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Anna: It implies the ocean is truly global

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and that the geological activity isn't just a

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recent or temporary phenomenon. At one pole,

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a sustained global heat source means this

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ocean has likely been stable and warm from

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for billions of years.

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Avery: And that is the magic ingredient, a stable

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environment. It gives life, if it were to

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start, a real chance to take hold and evolve.

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Anna: Precisely. We're talking about a world with

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liquid water, organic molecules, which

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Cassini also found, and now a long

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lasting source of energy. That's a perfect

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trifecta for habitability. It makes

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Enceladus arguably the most compelling target

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for future astrobiology missions.

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Avery: We just have to go back, we have to sample

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those plumes and see what's really in that

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water.

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And while a mission to Enceladus is still on

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the drawing board, our final story is about a

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mission that is very much on the launchpad.

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On November 9, 2025, which is

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this Sunday, Blue Origin is set to launch

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its first ever interplanetary mission

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using its heavy lift new Glenn rocket.

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Anna: This is a big step for the commercial space

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industry and it's a NASA funded mission

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they're carrying. Right. A great example of

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public private partnership it is.

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Avery: The payload is a mission called Escapade,

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which consists of two identical probes

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destined for Mars.

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Anna: Escapade. I like the name. What's their

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purpose?

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Avery: They are designed to solve one of Mars

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biggest how it lost its

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atmosphere. We know Mars was once

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warmer and wetter with a thicker atmosphere,

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but over billions of years it was stripped

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away by the solar wind.

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Anna: Right. And that happened because Mars lost

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its global magnetic field, which acts as a

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protective shield for a planet's atmosphere.

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Earth's magnetic field protects us from the

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same fate.

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Avery: Exactly. Mars now only has

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these localized remnant pockets of magnetism

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in its crust. The two Escapade spacecraft

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will orbit in formation, allowing one

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to measure the incoming solar wind while the

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other measures the atmospheric effects at

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that exact moment.

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Anna: This will give us the first ever 3D picture

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of how the solar wind is siphoning off what's

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left of the Martian air. It's fundamental

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science for understanding how a habitable

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planet can become an inhospitable one.

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A cautionary tale, perhaps a very important

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one.

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Avery: It's a fantastic mission and a huge milestone

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for Blue Origin. We'll be watching that

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launch closely.

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Anna: And with that, we're out of time for today's

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episode. What a journey across the cosmos.

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Avery: The universe never fails to deliver. A

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huge thank you to all of you for listening to

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Astronomy Daily. Join us next time for

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another journey through the cosmos. Until

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then, stay curious and keep looking up.

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Astronomy Daily

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stories we told

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Love

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story HM Soul.