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

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Anna: 60 million stars in a single

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image. Stay with us. Your universe just

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got a whole lot bigger.

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Avery: Hello, and welcome to Astronomy Daily, your

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daily dispatch from the final frontier. I'm,

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um, Avery.

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

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June, 2026, and we have a

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genuinely spectacular edition for you today.

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Six stories that together paint a portrait

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of just how active and extraordinary

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our universe is.

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Avery: Right, we've got a record shattering

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telescope image, a, uh, cosmic mystery solved

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by Hubble, the oldest scar on Earth,

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planets that defy everything we thought we

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knew about density, a rocket on a collision

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course with the Moon, and a space weather

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alert for our, uh, Southern Hemisphere

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listeners, all in about 25 minutes.

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Anna: Let's dive in.

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We're starting with an image that is, quite

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simply one of the most spectacular

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astronomical photographs ever produced.

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The European Space Agency has just released

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a breathtaking portrait of the heart of our

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own galaxy, captured by the Euclid Space

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Telescope. And it contains more than 60

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million individual stars.

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Avery: 60 million stars in a single

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frame. Let that settle for a moment. This is

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the largest high resolution visible light

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image of the Milky Way central bulge ever

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made. And it arrived in our news feeds just

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this week.

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Anna: Euclid, which was originally built to study

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dark matter and dark energy by surveying

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billions of distant galaxies, took a

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remarkable detour. Astronomers

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essentially asked it to do something

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completely outside its primary mission,

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to spend 26 hours staring at the

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dense, glittering core of our own

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galaxy.

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Avery: And it delivered. The resulting mosaic was

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stitched together from nine separate

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pointings of Euclid's visible light camera.

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Each individual pointing covered a patch of

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sky larger than the Full Moon. And the

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combined Image spans nearly 5 square

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degrees. That's the equivalent of about

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25 full moons laid side by side.

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Anna: What makes it technically remarkable is that

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Euclid's sharpness and sensitivity in

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visible light is comparable to Hubble's

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Wide Field Camera. But Euclid can Image an

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area 270 times larger

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in a single pointing. So in terms of

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sheer scale combined with resolution,

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this image is unprecedented.

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

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strategically important. This image is going

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to serve as a critical baseline reference for

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NASA's Nancy Grace Roman Telescope, which is

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due to launch in late August and will conduct

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its own Deep Galactic Bold survey beginning

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in 2027.

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Anna: Roman will search for exoplanets using a

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technique called gravitational microlensing,

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where a planet passing in front of a, uh,

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background star causes a tiny

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detectable brightening. To do that, well, you

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need to know the precise positions and

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movements of all those stars. And that's

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exactly what Euclid has now provided.

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Avery: One scientist put it beautifully. They said

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that in just 24 hours, Euclid captured the

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stars involved in all of Roman's future

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microlensing events before the planets and

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stars have even aligned Euclid. It's like

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taking a class photo before the school year

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begins.

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Anna: The Image also includes 51

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known planetary systems, dense

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molecular clouds that appear as dramatic

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dark patches, glowing emission nebulae,

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and young star clusters. And buried in those

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60 million stellar data points are

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likely thousands of undiscovered worlds

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patiently waiting for Roman to find them.

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Avery: An extraordinary image and a tremendous

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example of telescopes working together.

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Bravo, Euclid.

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Our second story takes us back much further

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in time to the very early universe, when the

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cosmos was still shrouded in a thick fog of

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neutral hydrogen gas. And the question of how

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that fog was lifted has puzzled astronomers

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for decades.

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Anna: Now, thanks to the Hubble Space Telescope,

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working in concert with James Webb and the

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Very Large Telescope in Chile, we may

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finally have a definitive an. And the

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discovery was published this week in the

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Astrophysical Journal.

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Avery: The galaxy at the center of this story is

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called MXDF Z. Uh, 4.

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4. Not the most poetic name. But

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what it represents is extraordinary.

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This galaxy existed just 1.4

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billion years after the Big Bang, right at

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the tail end of what astronomers call the era

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of reionization.

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

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billion or so years of the universe, the gas

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between stars and galaxies was neutral,

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opaque. Ultraviolet light couldn't travel

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through it. The universe was essentially

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foggy. Then, over hundreds of millions

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of years, that fog burned away, and the

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cosmos became the transparent,

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magnificent expanse we observe today.

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

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the great unsolved questions of cosmology.

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There were two main enormous black

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holes, or the first generations of hot,

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massive young stars. This week,

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Hubble has delivered the strongest evidence

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yet that it was the stars.

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

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4.4. It's about a hundred times

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smaller in area than our Milky Way, a

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tiny galaxy by any measure. But it's

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forming new stars 10 times faster than we

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are. And those young, hot, massive stars

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are packed into an incredibly compact

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cluster.

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Avery: Cram enough of those stars into a small

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enough space, and you create a furnace.

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The team estimates that between 50 and

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100% of the intense ultraviolet light from

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those stars is actually escaping the

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galaxy's gas, punching clean through it and

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ionizing the surrounding hydrogen fog.

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

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eventually explode as supernovae,

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blasting enormous bubbles in the gas that

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create even more pathways for the ionizing

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light to escape. It's a self reinforcing

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process.

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Avery: Before this discovery, astronomers had only

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found the galaxy emitting this kind of

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ionizing light From a time when the universe

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was 1.6 billion years old.

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MXDF, uh, 4.4 pushes that

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back to 1.4 billion years,

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closer than ever to the actual era of

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realization.

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Anna: What was previously considered impossible to

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detect because the fog itself was expected

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to absorb that ultraviolet light before it

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could reach us, has now been directly

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observed. This galaxy may be the smoking

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gun that solves one of cosmology's most

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enduring mysteries.

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

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going.

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Anna: You're listening to Astronomy Daily, season

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five, episode 125. If you're

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enjoying the show, please subscribe, leave us

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a review and share us with a friend who loves

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the stars. Find us at astronomydaily

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IO and follow us on socials.

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Avery: Astronedailypod Ah, here's a story with

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the wonderful local flavor. And it's a

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genuine scientific detective story.

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Anna: Researchers from Curtin University in Western

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Australia, working with the Geological Survey

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of Western Australia, have finally resolved a

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major scientific debate about what is

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officially the oldest known asteroid impact

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crater on Earth. Their paper was published

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this week in the journal Geology.

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Avery: The site in question is called the North Pole

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

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near any pole. It's in the remote Pilbara

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region of Western Australia, one of the most

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geologically ancient landscapes on our

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planet.

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Anna: Hm. For years, scientists debated just how

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old this impact structure actually was.

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One team estimated it at 3.47

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billion years old. Another challenged that,

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arguing it was at most 2.7 billion

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years old. The truth, it turns out, lies

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somewhere in between. And it still makes

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North Pole Dome comfortably the oldest impact

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crater known on Earth.

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Avery: The Curtin team used advanced mineral dating

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techniques, specifically focusing on tiny

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crystals of zircon, a mineral renowned for

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its ability to preserve geological time with

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extraordinary precision. Zircon

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contains trace amounts of uranium that slowly

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decay into lead. And by measuring that

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ratio, you can read the clock.

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Anna: The zircons at North Pole Dome had

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unusual branching skeletal shapes.

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The team interpreted these as impact

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modified crystals formed when older

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zircon was disrupted and partially

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remelted by the intense heat and pressure

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of an asteroid strike. Those crystals

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record an age of approximately

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3.024 billion years

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ago.

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Avery: To confirm it, they also dated a second

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mineral, apatite which formed as hot

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fluids moved through the shock damaged rocks

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after the impact. Remarkably, both

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dating systems gave the same answer. The

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North Pole Dome impact occurred around 3

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billion years ago, pushing Earth's known

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impact record deeper into geological time

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than any previously well dated crater.

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Anna: To put that in perspective, the next oldest

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confirmed impact structure on Earth is the

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Yarrabuba Crater, also in Western Australia.

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Dated to 2.23 billion years

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ago, North Pole Dome beats it by

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nearly 800 million years.

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Avery: There's also a haunting proximity.

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The oldest known traces of life on Earth,

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limestone stromatolites made by ancient

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bacteria, are found just a few few

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kilometers from North Pole Dome. Those

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stromatolites are about 3.5 billion

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years old. So when this asteroid hit,

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life on Earth was already well established,

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and it survived.

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Anna: The story of Western Australia as a

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geological archive of our planet's earliest

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history just keeps getting richer.

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Truly remarkable science and a wonderful

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home story for our Australian listeners.

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Now, a story that will make you question

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everything you thought you knew about what a

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planet can be.

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Avery: Researchers led by the University of Oxford,

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in collaboration with teams in France and the

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UK have confirmed the discovery of two

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record breaking exoplanets with densities

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so low they are literally lighter than cotton

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candy. The paper is published today in the

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Monthly Notices of the Royal Astronomical

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Society.

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Anna: These planets are named TOI

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791B and TOI

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791C, and they orbit a, uh,

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dwarf star located about

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1,110 light years from

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Earth in the southern constellation of

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Volans. Both planets are roughly the size of

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Jupiter, but that's where the similarity

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ends.

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Avery: Jupiter has an average density of about

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1.33 grams per cubic centimeter.

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These two planets have densities of

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0.038 grams per cubic

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centimeter and 0.047

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grams per cubic centimeter, respectively. To

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give you a sense of scale that's less dense

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than cotton candy, which typically weighs in

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around 0.05. They're more like

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enormous gossamer bubbles of gas than

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anything we'd traditionally call a planet.

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Anna: They've been dubbed superpuff planets, and

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only a handful of such objects are known.

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Finding two in the same planetary system is

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extraordinarily rare. Lead author

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Dr. George Dransfield from Oxford

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described them as the lightest planets for

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their size ever confirmed.

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Avery: The discovery required eight years of

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observations from telescopes around the

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world. Crucially, it relied on data from the

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Antarctic Search for Transiting Exoplanets

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Telescope, known as ASTEP UH at Concordia

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Station in Antarctica. The Antarctic Winter

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provided months of continuous darkness,

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allowing the team to capture each planet's

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transit, its passage across its host star in

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a single uninterrupted observation lasting

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more than 11 hours. These are the

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longest continuous planetary transits ever

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observed from the ground in their entirety.

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Anna: How planets this enormous can be

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so impossibly light is still an open

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question. The leading theory is that they

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possess vast hydrogen and helium rich

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atmospheres that inflate their size while

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contributing very little mass. They may also

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be slowly losing material as their star's

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radiation strips away their outer layers.

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Avery: Dr. Dransfield noted that their extremely low

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densities make them ideal targets for future

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atmospheric study because with so little mass

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holding everything together, the atmosphere

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should be puffed up and easier to

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characterize. With telescopes like James

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Webb, we may learn a lot about how planetary

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systems form and evolve from these two

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unlikely worlds.

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Anna: Giant as Jupiter light as a carnival

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treat, the universe continues to

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outpace our imagination.

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

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moon is about to get hit by a piece of a

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SpaceX rocket.

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

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It's a piece of orbital debris,

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specifically the spent upper stage of a

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SpaceX Falcon 9 rocket left over from the

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January 2025 launch that sent Firefly

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Aerospace's Blue Ghost lander and the

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Japanese ispace Hakuto R2 mission

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lander toward the Moon.

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Avery: After delivering its payload, the upper stage

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was left on a trajectory with nowhere to go

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but eventually into the lunar surface.

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Orbital analyst Bill Gray of Project Pluto

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tracked it down using his telescope tracking

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Software, and in September 2025

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he calculated that it would impact the Moon

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on or around August 5th this year.

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Anna: The stage weighs approximately 4 metric

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tons and is traveling at over 2 kilometers

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00:14:25.800 --> 00:14:28.320
per second. It's expected to strike near

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Einstein Crater on the moon's western limb,

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though the precise impact point is still

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being refined. Another possible target is

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Bell Crater, just out of sight on the far

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side.

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Avery: Now the question everyone wants answered

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Will we be able to see it? And the honest

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answer from the Experts is maybe.

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

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Meteoroid Environment Office at Marshall

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Space Flight center, describes the visibility

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as very subtle and very,

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very hard to see, if not impossible,

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

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the impact will kick up enormous amounts of

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lunar dust and rock, and if it occurs close

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

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material rising against the black sky might

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be detectable.

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Avery: Bill Gray himself has gone through a journey

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on this from probably visible to

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probably not to maybe. He

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says the timing and location of the impact

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are still fuzzy by minutes and dozens of

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kilometers, but they'll refine that as August

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approaches.

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

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Reconnaissance Orbiter will be passing over

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the projected crash site about seven days

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before the impact and again about seven days

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

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Earth, we will get before and after images

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of the new crater it creates.

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Avery: And there's a genuine citizen science

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opportunity here, too. A program called

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Impact flash, run through NASA's Solar System

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Exploration Research Virtual Institute,

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is calling on backyard astronomers to watch

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and report. Because impact flashes are

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so brief and can mimic cosmic ray hits on

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camera sensors, having multiple observers in

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different locations simultaneously is

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enormously valuable.

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

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hardware launched with the explicit purpose

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of reaching the Moon, but in a completely

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different way to how its passengers got

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there. Another reminder, as one NASA

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scientist put it, that the Moon is a dynamic,

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ever changing environment, and we are

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contributing to that change.

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

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history in the making.

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

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and we have some genuinely exciting space

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weather news for our listeners in the

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Southern hemisphere tonight.

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Avery: A G1 minor geomagnetic

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storm struck in the early hours of yesterday

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morning, triggered by fast solar wind from a

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coronal hole combining with what's called a

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UH CO rotating interaction region, or

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00:17:01.020 --> 00:17:03.620
cir. A, uh, glancing blow from a

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coronal mass ejection launched on June 20

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00:17:06.460 --> 00:17:09.100
may have also contributed. The disturbance

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hit the G1 threshold at 4.43in the

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morning UTC.

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

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five step geomagnetic scale, but it's enough

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to push Auroras to higher mid latitudes.

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And here's the headline for tonight and

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tomorrow night. More unsettled conditions are

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expected with another G1 interval possible

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late tonight as, uh, the coronal hol stream

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continues to strengthen.

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Avery: If the interplanetary magnetic field flips

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southward and stays that way for long enough,

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aurora watchers in Tasmania, New

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Zealand's south island and southern parts of

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Victoria and South Australia could be in with

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a genuine chance tonight. Winter nights in

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the Southern Hemisphere right now are long

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and dark perfect conditions if the activity

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picks up.

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Anna: Northern Hemisphere listeners, the short June

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nights are working against you significantly.

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If the KP index does hit 5 or above,

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you'd need to be at high latitudes in

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Scandinavia, Iceland or northern

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Scotland to have a realistic chance.

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Avery: But there's an even bigger story developing

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on the sun itself. A large, complex

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new sunspot region designated

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00:18:19.570 --> 00:18:22.410
AR4478 is

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rotating into Earth view over the solar

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eastern horizon. It announced its arrival

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with a C8.7 class flare,

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which was partially blocked by the solar

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limb, meaning the actual energy release

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was likely considerably more powerful than

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the recorded level.

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00:18:39.430 --> 00:18:42.310
Anna: AR4478 appears to be a

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substantial magnetically complex region

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00:18:45.430 --> 00:18:47.790
first spotted on the Sun's far side by the

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00:18:47.790 --> 00:18:50.590
Solar Orbiter spacecraft as it rotates

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00:18:50.590 --> 00:18:52.830
fully onto the Earth facing disk. Over the

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next day or two, the chances of M M class

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00:18:55.230 --> 00:18:57.910
flares moderate, potentially auroral

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are expected to increase significantly.

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Avery: So keep an eye on space weather updates over

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00:19:02.960 --> 00:19:05.400
the coming days. This one bears watching.

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00:19:05.640 --> 00:19:08.000
Check apps like Space Weather Live or Earth

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Sky's Sun News page for the latest.

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

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solar maximum in the current 11 year solar

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cycle, which means heightened solar activity

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

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these events will keep coming.

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

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00:19:24.640 --> 00:19:27.160
astronomy Daily Season 5 Episode

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00:19:27.160 --> 00:19:29.460
125 what a show it's been.

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00:19:29.700 --> 00:19:32.580
Anna: We covered 60 million stars in a

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00:19:32.580 --> 00:19:35.220
single Euclid image, a tiny Hubble

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00:19:35.220 --> 00:19:37.660
galaxy that may have cleared the cosmic fog

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00:19:37.660 --> 00:19:40.620
of the early universe, the 3 billion year

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old Australian crater that is officially the

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oldest scar on our planet, two

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planet sized cotton candy puffs defying

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everything we knew about density, a uh, rogue

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SpaceX rocket stage headed for the Moon in

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August, and a live solar alert for

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aurora hunters in the south.

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

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today, The Euclid Space Telescope's

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galactic bulge image released this week

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includes 51 already known planetary

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systems embedded within those 60 million

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stars. Every single one of those planets

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was discovered by noticing a tiny dimming

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of its host star's light, a dimming

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00:20:20.820 --> 00:20:23.780
equivalent to watching a flea walk across a

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car headlight from several kilometers away.

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Anna: Thank you so much for spending this time with

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00:20:29.110 --> 00:20:31.750
us. If you enjoyed today's episode, please

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00:20:31.750 --> 00:20:34.230
subscribe. Leave us a review on your podcast

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00:20:34.230 --> 00:20:37.030
platform of choice, and share Astronomy Daily

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00:20:37.030 --> 00:20:39.030
with someone who looks up at the sky and

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00:20:39.030 --> 00:20:41.790
wonders. Find us at astronomydaily

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00:20:41.950 --> 00:20:44.750
IO and follow us on X, Facebook,

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00:20:44.990 --> 00:20:46.990
Instagram, TikTok and Tumblr

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00:20:47.230 --> 00:20:50.110
astrodaily Pod until next time from

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00:20:50.110 --> 00:20:52.910
Avery: both of us, Clear Skies Clear skies.

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00:20:53.150 --> 00:20:54.590
Astronomy Day

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Stories.