Cosmic Auroras, Planetary Demise, and Martian Mysteries

Avery: Welcome to Astronomy Daily, the podcast that

brings you the universe one story at a time.

I'm your host, Avery.

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

to be with you all again, Avery.

Here in the northern hemisphere, it feels

like the nights are really drawing in.

Getting colder, darker.

Avery: They certainly are. But that darkness

isn't always a bad thing, especially when it

becomes a canvas for some of the universe's

most incredible art. And we're starting

today's show with just that.

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

from spectacular atmospheric light shows

right here at home to the ultimate

fate of Earth itself.

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

outside our solar system, find a beacon of

hope on an icy moon, and preview an exciting

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

it.

Anna: I'm ready if you are.

Avery: Alrighty. Our first story is a visual

feast for anyone lucky enough to be in the

right place at the right time. Between

November 5th and 8th, 2025, the night

sky put on a show for the ages. A

powerful geomagnetic storm triggered stunning

auroras.

Anna: It really was something special. This was

classified as a G3 class storm on the

five point scale, which is considered strong.

It was all thanks to a significant coronal

mass ejection, or cme, that

erupted from the Sun a few days prior.

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

threw a massive blob of plasma and

magnetic field our way.

Anna: Exactly. When that wave of charged

particles hits our magnetosphere, it

channels them towards the poles. They rain

down into our upper atmosphere, collide with

air molecules, and energize them, causing

them to glow. The. The beautiful greens are

from oxygen, while rarer pinks and

reds come from nitrogen.

Avery: And this storm was powerful enough that the

lights were seen much farther south than

usual. We saw incredible photos and time

lapses from the northern United States, the

UK, and all across Scandinavia. It must

have been just breathtaking to see in person.

Anna: It truly is an experience that connects you

to the cosmos. It's a vivid, dynamic

reminder that we live inside the atmosphere

of a star.

Avery: It's.

Anna: And that our sun is an active, powerful

force. We're currently in an active period

of the solar cycle, so we might get a few

more shows like this in the coming years.

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

and a great way to start our cosmic journey

today.

Anna: From the beautiful effects of our star's

activity to a more sobering look at its

eventual demise.

Our next story comes from NASA's Transiting

Exoplanet Survey Satellite, which or TESS.

And it paints a stark picture of the fate of

planets orbiting sun like stars.

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

exoplanets. But it's great at just watching

stars. What did it see this time?

Anna: It was watching older stars, those beginning

to enter their red giant phase. And the new

study confirms that these swelling stars are

engulfing their inner planets far more often

than some models predicted. They the evidence

is in the starlight itself. They can detect

the chemical signatures of planetary material

being consumed by the star.

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

It's more like being vaporized and

eaten.

Anna: A very accurate description. As a star

like our sun exhausts hydrogen fuel in its

core, it starts burning it in a shell, which

causes its outer layers to expand enormously

and it can swell to hundreds of times its

original size.

Avery: And um, any planets in the way.

Anna: Any planets in the way are first subjected to

immense tidal forces that can tear them

apart. And then they are swallowed by the

star's expanding atmosphere, the

photosphere.

Avery: Which brings us to the big scary.

What does this mean for Mercury, Venus and

us, uh, here on Earth?

Anna: Well, Mercury and Venus are almost

certainly doomed. As for Earth, the

picture is now looking grimmer. While some

models suggested Earth's orbit might widen

and save us, this new data suggests

the Sun's expansion will be too aggressive to

overcome that shift.

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

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

need to sell your stocks just yet.

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

celestial mechanics that govern the birth and

death of worlds. It gives us a real sense of

cosmic perspective. Our planet has an

expiration date written in the stars.

Avery: Okay. From a threat 5 billion years

away to one that is, well, less

predictable. A fascinating new piece of

research is helping us understand the risk of

impacts from interstellar objects

or ISOs.

Anna: These are the cosmic nomads. Objects like

asteroids and comets that have been ejected

from their own star systems and are now

wandering the Milky Way.

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

visitors so far that we know of. The strange

cigar shaped Oumuamua in 2017

and the more comet like Borisov in

2019. Then there's the current one

everyone's talking about. 3i

Atlas those three flybys prove that these

objects are out there.

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

there are and what the chances are that one

might hit us.

Avery: Precisely. This new study tells us where

we're most likely to see them coming from the

solar apex. That's the direction our

solar system is traveling as we orbit the

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

windshield, so to speak.

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

these objects as we travel through the

galaxy.

Avery: It does. The study also pointed to the

galactic plane as another likely source.

Now, to be clear, the researchers stress that

the probability of an impact on from a large

ISO remains extremely low.

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

But for planetary defense experts, this is

crucial information. It tells them where to

prioritize their search efforts. It's about

being smart and looking in the right

direction for these very faint, very fast

moving objects.

Anna: So it's another step towards creating a

comprehensive map of potential hazards both

from within and without our solar system.

Fascinating stuff.

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

travel to Saturn's icy moon

Enceladus. It's getting more promising in the

search for extraterrestrial life, thanks to

a fresh look at old data from the

Cassini mission.

Anna: It absolutely is. Cassini orbited

Saturn from 2004 to 2017,

and scientists are still making incredible

discoveries from its data archives. The big

news we've known for years is the South Pole

with its Deimos tiger stripe fissures that

blast plumes of water from a subsurface ocean

into space.

Avery: Yeah, an underground ocean of

liquid water. That m alone is amazing.

Anna: It is. But the North Pole was always

considered the boring one. Frozen,

ancient and inactive. Well, by

reanalyzing thermal data from Cassini's

flybys, scientists have now discovered a

significant heat signature coming from the

North Pole as well. The ice is much thicker

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

definitely there.

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

heating it at both poles. What does that

imply for the ocean?

Anna: It implies the ocean is truly global

and that the geological activity isn't just a

recent or temporary phenomenon. At one pole,

a sustained global heat source means this

ocean has likely been stable and warm from

for billions of years.

Avery: And that is the magic ingredient, a stable

environment. It gives life, if it were to

start, a real chance to take hold and evolve.

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

liquid water, organic molecules, which

Cassini also found, and now a long

lasting source of energy. That's a perfect

trifecta for habitability. It makes

Enceladus arguably the most compelling target

for future astrobiology missions.

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

those plumes and see what's really in that

water.

And while a mission to Enceladus is still on

the drawing board, our final story is about a

mission that is very much on the launchpad.

On November 9, 2025, which is

this Sunday, Blue Origin is set to launch

its first ever interplanetary mission

using its heavy lift new Glenn rocket.

Anna: This is a big step for the commercial space

industry and it's a NASA funded mission

they're carrying. Right. A great example of

public private partnership it is.

Avery: The payload is a mission called Escapade,

which consists of two identical probes

destined for Mars.

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

purpose?

Avery: They are designed to solve one of Mars

biggest how it lost its

atmosphere. We know Mars was once

warmer and wetter with a thicker atmosphere,

but over billions of years it was stripped

away by the solar wind.

Anna: Right. And that happened because Mars lost

its global magnetic field, which acts as a

protective shield for a planet's atmosphere.

Earth's magnetic field protects us from the

same fate.

Avery: Exactly. Mars now only has

these localized remnant pockets of magnetism

in its crust. The two Escapade spacecraft

will orbit in formation, allowing one

to measure the incoming solar wind while the

other measures the atmospheric effects at

that exact moment.

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

of how the solar wind is siphoning off what's

left of the Martian air. It's fundamental

science for understanding how a habitable

planet can become an inhospitable one.

A cautionary tale, perhaps a very important

one.

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

for Blue Origin. We'll be watching that

launch closely.

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

episode. What a journey across the cosmos.

Avery: The universe never fails to deliver. A

huge thank you to all of you for listening to

Astronomy Daily. Join us next time for

another journey through the cosmos. Until

then, stay curious and keep looking up.

Astronomy Daily

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