60 Million Stars Captured, Cosmic Fog Cleared, and Earth's Oldest Impact Crater Revealed

Anna: 60 million stars in a single

image. Stay with us. Your universe just

got a whole lot bigger.

Avery: Hello, and welcome to Astronomy Daily, your

daily dispatch from the final frontier. I'm,

um, Avery.

Anna: And I'm anna. It's Friday, the 27th of

June, 2026, and we have a

genuinely spectacular edition for you today.

Six stories that together paint a portrait

of just how active and extraordinary

our universe is.

Avery: Right, we've got a record shattering

telescope image, a, uh, cosmic mystery solved

by Hubble, the oldest scar on Earth,

planets that defy everything we thought we

knew about density, a rocket on a collision

course with the Moon, and a space weather

alert for our, uh, Southern Hemisphere

listeners, all in about 25 minutes.

Anna: Let's dive in.

We're starting with an image that is, quite

simply one of the most spectacular

astronomical photographs ever produced.

The European Space Agency has just released

a breathtaking portrait of the heart of our

own galaxy, captured by the Euclid Space

Telescope. And it contains more than 60

million individual stars.

Avery: 60 million stars in a single

frame. Let that settle for a moment. This is

the largest high resolution visible light

image of the Milky Way central bulge ever

made. And it arrived in our news feeds just

this week.

Anna: Euclid, which was originally built to study

dark matter and dark energy by surveying

billions of distant galaxies, took a

remarkable detour. Astronomers

essentially asked it to do something

completely outside its primary mission,

to spend 26 hours staring at the

dense, glittering core of our own

galaxy.

Avery: And it delivered. The resulting mosaic was

stitched together from nine separate

pointings of Euclid's visible light camera.

Each individual pointing covered a patch of

sky larger than the Full Moon. And the

combined Image spans nearly 5 square

degrees. That's the equivalent of about

25 full moons laid side by side.

Anna: What makes it technically remarkable is that

Euclid's sharpness and sensitivity in

visible light is comparable to Hubble's

Wide Field Camera. But Euclid can Image an

area 270 times larger

in a single pointing. So in terms of

sheer scale combined with resolution,

this image is unprecedented.

Avery: And it's not just beautiful science, it's

strategically important. This image is going

to serve as a critical baseline reference for

NASA's Nancy Grace Roman Telescope, which is

due to launch in late August and will conduct

its own Deep Galactic Bold survey beginning

in 2027.

Anna: Roman will search for exoplanets using a

technique called gravitational microlensing,

where a planet passing in front of a, uh,

background star causes a tiny

detectable brightening. To do that, well, you

need to know the precise positions and

movements of all those stars. And that's

exactly what Euclid has now provided.

Avery: One scientist put it beautifully. They said

that in just 24 hours, Euclid captured the

stars involved in all of Roman's future

microlensing events before the planets and

stars have even aligned Euclid. It's like

taking a class photo before the school year

begins.

Anna: The Image also includes 51

known planetary systems, dense

molecular clouds that appear as dramatic

dark patches, glowing emission nebulae,

and young star clusters. And buried in those

60 million stellar data points are

likely thousands of undiscovered worlds

patiently waiting for Roman to find them.

Avery: An extraordinary image and a tremendous

example of telescopes working together.

Bravo, Euclid.

Our second story takes us back much further

in time to the very early universe, when the

cosmos was still shrouded in a thick fog of

neutral hydrogen gas. And the question of how

that fog was lifted has puzzled astronomers

for decades.

Anna: Now, thanks to the Hubble Space Telescope,

working in concert with James Webb and the

Very Large Telescope in Chile, we may

finally have a definitive an. And the

discovery was published this week in the

Astrophysical Journal.

Avery: The galaxy at the center of this story is

called MXDF Z. Uh, 4.

4. Not the most poetic name. But

what it represents is extraordinary.

This galaxy existed just 1.4

billion years after the Big Bang, right at

the tail end of what astronomers call the era

of reionization.

Anna: Let me explain what that means. For the first

billion or so years of the universe, the gas

between stars and galaxies was neutral,

opaque. Ultraviolet light couldn't travel

through it. The universe was essentially

foggy. Then, over hundreds of millions

of years, that fog burned away, and the

cosmos became the transparent,

magnificent expanse we observe today.

Avery: But what burned it away? That has been one of

the great unsolved questions of cosmology.

There were two main enormous black

holes, or the first generations of hot,

massive young stars. This week,

Hubble has delivered the strongest evidence

yet that it was the stars.

Anna: Here's what's remarkable about MXDF Z

4.4. It's about a hundred times

smaller in area than our Milky Way, a

tiny galaxy by any measure. But it's

forming new stars 10 times faster than we

are. And those young, hot, massive stars

are packed into an incredibly compact

cluster.

Avery: Cram enough of those stars into a small

enough space, and you create a furnace.

The team estimates that between 50 and

100% of the intense ultraviolet light from

those stars is actually escaping the

galaxy's gas, punching clean through it and

ionizing the surrounding hydrogen fog.

Anna: And what's more, many of those massive stars

eventually explode as supernovae,

blasting enormous bubbles in the gas that

create even more pathways for the ionizing

light to escape. It's a self reinforcing

process.

Avery: Before this discovery, astronomers had only

found the galaxy emitting this kind of

ionizing light From a time when the universe

was 1.6 billion years old.

MXDF, uh, 4.4 pushes that

back to 1.4 billion years,

closer than ever to the actual era of

realization.

Anna: What was previously considered impossible to

detect because the fog itself was expected

to absorb that ultraviolet light before it

could reach us, has now been directly

observed. This galaxy may be the smoking

gun that solves one of cosmology's most

enduring mysteries.

Avery: And we're only at, uh, story two. Let's keep

going.

Anna: You're listening to Astronomy Daily, season

five, episode 125. If you're

enjoying the show, please subscribe, leave us

a review and share us with a friend who loves

the stars. Find us at astronomydaily

IO and follow us on socials.

Avery: Astronedailypod Ah, here's a story with

the wonderful local flavor. And it's a

genuine scientific detective story.

Anna: Researchers from Curtin University in Western

Australia, working with the Geological Survey

of Western Australia, have finally resolved a

major scientific debate about what is

officially the oldest known asteroid impact

crater on Earth. Their paper was published

this week in the journal Geology.

Avery: The site in question is called the North Pole

Dome. And yes, despite the name, it's not

near any pole. It's in the remote Pilbara

region of Western Australia, one of the most

geologically ancient landscapes on our

planet.

Anna: Hm. For years, scientists debated just how

old this impact structure actually was.

One team estimated it at 3.47

billion years old. Another challenged that,

arguing it was at most 2.7 billion

years old. The truth, it turns out, lies

somewhere in between. And it still makes

North Pole Dome comfortably the oldest impact

crater known on Earth.

Avery: The Curtin team used advanced mineral dating

techniques, specifically focusing on tiny

crystals of zircon, a mineral renowned for

its ability to preserve geological time with

extraordinary precision. Zircon

contains trace amounts of uranium that slowly

decay into lead. And by measuring that

ratio, you can read the clock.

Anna: The zircons at North Pole Dome had

unusual branching skeletal shapes.

The team interpreted these as impact

modified crystals formed when older

zircon was disrupted and partially

remelted by the intense heat and pressure

of an asteroid strike. Those crystals

record an age of approximately

3.024 billion years

ago.

Avery: To confirm it, they also dated a second

mineral, apatite which formed as hot

fluids moved through the shock damaged rocks

after the impact. Remarkably, both

dating systems gave the same answer. The

North Pole Dome impact occurred around 3

billion years ago, pushing Earth's known

impact record deeper into geological time

than any previously well dated crater.

Anna: To put that in perspective, the next oldest

confirmed impact structure on Earth is the

Yarrabuba Crater, also in Western Australia.

Dated to 2.23 billion years

ago, North Pole Dome beats it by

nearly 800 million years.

Avery: There's also a haunting proximity.

The oldest known traces of life on Earth,

limestone stromatolites made by ancient

bacteria, are found just a few few

kilometers from North Pole Dome. Those

stromatolites are about 3.5 billion

years old. So when this asteroid hit,

life on Earth was already well established,

and it survived.

Anna: The story of Western Australia as a

geological archive of our planet's earliest

history just keeps getting richer.

Truly remarkable science and a wonderful

home story for our Australian listeners.

Now, a story that will make you question

everything you thought you knew about what a

planet can be.

Avery: Researchers led by the University of Oxford,

in collaboration with teams in France and the

UK have confirmed the discovery of two

record breaking exoplanets with densities

so low they are literally lighter than cotton

candy. The paper is published today in the

Monthly Notices of the Royal Astronomical

Society.

Anna: These planets are named TOI

791B and TOI

791C, and they orbit a, uh,

dwarf star located about

1,110 light years from

Earth in the southern constellation of

Volans. Both planets are roughly the size of

Jupiter, but that's where the similarity

ends.

Avery: Jupiter has an average density of about

1.33 grams per cubic centimeter.

These two planets have densities of

0.038 grams per cubic

centimeter and 0.047

grams per cubic centimeter, respectively. To

give you a sense of scale that's less dense

than cotton candy, which typically weighs in

around 0.05. They're more like

enormous gossamer bubbles of gas than

anything we'd traditionally call a planet.

Anna: They've been dubbed superpuff planets, and

only a handful of such objects are known.

Finding two in the same planetary system is

extraordinarily rare. Lead author

Dr. George Dransfield from Oxford

described them as the lightest planets for

their size ever confirmed.

Avery: The discovery required eight years of

observations from telescopes around the

world. Crucially, it relied on data from the

Antarctic Search for Transiting Exoplanets

Telescope, known as ASTEP UH at Concordia

Station in Antarctica. The Antarctic Winter

provided months of continuous darkness,

allowing the team to capture each planet's

transit, its passage across its host star in

a single uninterrupted observation lasting

more than 11 hours. These are the

longest continuous planetary transits ever

observed from the ground in their entirety.

Anna: How planets this enormous can be

so impossibly light is still an open

question. The leading theory is that they

possess vast hydrogen and helium rich

atmospheres that inflate their size while

contributing very little mass. They may also

be slowly losing material as their star's

radiation strips away their outer layers.

Avery: Dr. Dransfield noted that their extremely low

densities make them ideal targets for future

atmospheric study because with so little mass

holding everything together, the atmosphere

should be puffed up and easier to

characterize. With telescopes like James

Webb, we may learn a lot about how planetary

systems form and evolve from these two

unlikely worlds.

Anna: Giant as Jupiter light as a carnival

treat, the universe continues to

outpace our imagination.

Avery: Mark your calendars, because on August 5, the

moon is about to get hit by a piece of a

SpaceX rocket.

Anna: This is not a drill, and it's not a mission.

It's a piece of orbital debris,

specifically the spent upper stage of a

SpaceX Falcon 9 rocket left over from the

January 2025 launch that sent Firefly

Aerospace's Blue Ghost lander and the

Japanese ispace Hakuto R2 mission

lander toward the Moon.

Avery: After delivering its payload, the upper stage

was left on a trajectory with nowhere to go

but eventually into the lunar surface.

Orbital analyst Bill Gray of Project Pluto

tracked it down using his telescope tracking

Software, and in September 2025

he calculated that it would impact the Moon

on or around August 5th this year.

Anna: The stage weighs approximately 4 metric

tons and is traveling at over 2 kilometers

per second. It's expected to strike near

Einstein Crater on the moon's western limb,

though the precise impact point is still

being refined. Another possible target is

Bell Crater, just out of sight on the far

side.

Avery: Now the question everyone wants answered

Will we be able to see it? And the honest

answer from the Experts is maybe.

Anna: NASA's William Cook, Program manager of the

Meteoroid Environment Office at Marshall

Space Flight center, describes the visibility

as very subtle and very,

very hard to see, if not impossible,

but there's always a chance. He notes, that

the impact will kick up enormous amounts of

lunar dust and rock, and if it occurs close

enough to the Moon's limb, a plume of ejected

material rising against the black sky might

be detectable.

Avery: Bill Gray himself has gone through a journey

on this from probably visible to

probably not to maybe. He

says the timing and location of the impact

are still fuzzy by minutes and dozens of

kilometers, but they'll refine that as August

approaches.

Anna: Here's the reassuring part. NASA's Lunar

Reconnaissance Orbiter will be passing over

the projected crash site about seven days

before the impact and again about seven days

after. So even if we can't see the flash from

Earth, we will get before and after images

of the new crater it creates.

Avery: And there's a genuine citizen science

opportunity here, too. A program called

Impact flash, run through NASA's Solar System

Exploration Research Virtual Institute,

is calling on backyard astronomers to watch

and report. Because impact flashes are

so brief and can mimic cosmic ray hits on

camera sensors, having multiple observers in

different locations simultaneously is

enormously valuable.

Anna: It's a fascinating story, a piece of

hardware launched with the explicit purpose

of reaching the Moon, but in a completely

different way to how its passengers got

there. Another reminder, as one NASA

scientist put it, that the Moon is a dynamic,

ever changing environment, and we are

contributing to that change.

Avery: Set a reminder for August 5th. It might be

history in the making.

Anna: Now it's time for your skywatching update,

and we have some genuinely exciting space

weather news for our listeners in the

Southern hemisphere tonight.

Avery: A G1 minor geomagnetic

storm struck in the early hours of yesterday

morning, triggered by fast solar wind from a

coronal hole combining with what's called a

UH CO rotating interaction region, or

cir. A, uh, glancing blow from a

coronal mass ejection launched on June 20

may have also contributed. The disturbance

hit the G1 threshold at 4.43in the

morning UTC.

Anna: Now, a UH G1 storm is the lowest level on the

five step geomagnetic scale, but it's enough

to push Auroras to higher mid latitudes.

And here's the headline for tonight and

tomorrow night. More unsettled conditions are

expected with another G1 interval possible

late tonight as, uh, the coronal hol stream

continues to strengthen.

Avery: If the interplanetary magnetic field flips

southward and stays that way for long enough,

aurora watchers in Tasmania, New

Zealand's south island and southern parts of

Victoria and South Australia could be in with

a genuine chance tonight. Winter nights in

the Southern Hemisphere right now are long

and dark perfect conditions if the activity

picks up.

Anna: Northern Hemisphere listeners, the short June

nights are working against you significantly.

If the KP index does hit 5 or above,

you'd need to be at high latitudes in

Scandinavia, Iceland or northern

Scotland to have a realistic chance.

Avery: But there's an even bigger story developing

on the sun itself. A large, complex

new sunspot region designated

AR4478 is

rotating into Earth view over the solar

eastern horizon. It announced its arrival

with a C8.7 class flare,

which was partially blocked by the solar

limb, meaning the actual energy release

was likely considerably more powerful than

the recorded level.

Anna: AR4478 appears to be a

substantial magnetically complex region

first spotted on the Sun's far side by the

Solar Orbiter spacecraft as it rotates

fully onto the Earth facing disk. Over the

next day or two, the chances of M M class

flares moderate, potentially auroral

are expected to increase significantly.

Avery: So keep an eye on space weather updates over

the coming days. This one bears watching.

Check apps like Space Weather Live or Earth

Sky's Sun News page for the latest.

Anna: And on a broader note, we are currently near

solar maximum in the current 11 year solar

cycle, which means heightened solar activity

is the new normal. For the next year or two,

these events will keep coming.

Avery: And that brings us to the end of today's

astronomy Daily Season 5 Episode

125 what a show it's been.

Anna: We covered 60 million stars in a

single Euclid image, a tiny Hubble

galaxy that may have cleared the cosmic fog

of the early universe, the 3 billion year

old Australian crater that is officially the

oldest scar on our planet, two

planet sized cotton candy puffs defying

everything we knew about density, a uh, rogue

SpaceX rocket stage headed for the Moon in

August, and a live solar alert for

aurora hunters in the south.

Avery: Before we go, our ah, did you'd know for

today, The Euclid Space Telescope's

galactic bulge image released this week

includes 51 already known planetary

systems embedded within those 60 million

stars. Every single one of those planets

was discovered by noticing a tiny dimming

of its host star's light, a dimming

equivalent to watching a flea walk across a

car headlight from several kilometers away.

Anna: Thank you so much for spending this time with

us. If you enjoyed today's episode, please

subscribe. Leave us a review on your podcast

platform of choice, and share Astronomy Daily

with someone who looks up at the sky and

wonders. Find us at astronomydaily

IO and follow us on X, Facebook,

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astrodaily Pod until next time from

Avery: both of us, Clear Skies Clear skies.

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