The Crater Makers: Falcon 9 Hits the Moon Tomorrow | Today’s Space News

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Anna: Sometime tomorrow morning, a piece of a

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rocket that has been lost in space for a year

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and a half is going to hit the moon and dig

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a brand new crater into a world that has kept

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its scars for 4 billion years.

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Avery: No one planned it, no one can stop it. And a

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small army of astronomers have set their

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alarms to watch and good

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Anna: day and welcome to Astronomy Daily. I'm

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Anna.

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Avery: And I'm Avery. Today is all about impacts.

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The ones we make and the ones the universe

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made long before us.

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Anna: A dead Falcon nine about to punch the moon.

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The asteroid that may have charbroiled the

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dinosaurs. Within hours, the ancient smash

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up that shattered Neptune's moons. And then

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to zoom right out, a new map that just

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doubled the X ray sky.

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Avery: Plus a uh, both hemisphere skywatch with a

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genuinely special comet in it. Let's get into

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it.

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Anna: So let's start with the story everyone will

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be talking about tomorrow. Early on Wednesday

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5 August, at about 06:35

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Universal Time, a spent upper stage of a

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SpaceX Falcon 9 is going to slam into

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the far western edge of the Moon's near side,

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close to a feature called Einstein Crater.

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Avery: And um, this isn't a controlled landing gone

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wrong. This is a genuinely derelict object.

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Space junk finally running out of road.

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Anna: Exactly. Let's rewind back.

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In January 2025 a Falcon

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9 launched from Kennedy Space center carrying

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two moon bound Firefly's

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Blee Ghost which went on to land beautifully,

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and Ispace's resilience which

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sadly didn't survive its own touchdown.

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The landers separated and went on their way.

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But the rocket's upper stage, the big

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second stage tube that does the final push,

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was left stranded, too high to

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Avery: fall straight back to Earth, too slow to

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escape cleanly. So it just wandered

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for about 18

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Anna: months in a long chaotic loop shaped

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by the tug of the Earth, the Moon, the sun

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and even the faint pressure of sunlight

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itself. It's cataloged unglamorously

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as 2025010

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D. And an independent astronomer named

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Bill Gray, who runs the tracking project

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Project Pluto, has been following it the

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whole way.

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Avery: This is the same Bill Gray who called the

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last one, isn't it?

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Anna: It is. A few years back he identified

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another derelict stage on a lunar collision

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course. This is his second and around

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March, watching the numbers tighten, he

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realized this one wasn't going to be a near

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miss. It was going to connect.

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Avery: So give us the ballistics. How hard does a

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thing like this hit?

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Anna: It's roughly a four ton object, about

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a 12 meter metal tube arriving at

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something like two and a half kilometers a

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second. That's about 5,500

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miles an hour, comfortably faster than a

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rifle bullet. The energy release is on the

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order of three tons of tnt.

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Avery: And um, what does that carve out?

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Anna: Best estimates put the new crater somewhere

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between about 17 and 27

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meters across and a few meters deep,

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small on a lunar scale. But here's the thing

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that has scientists genuinely excited.

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We will know almost to the second and to

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within a few kilometers exactly when

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and where a known object of known mass

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and known speed hit. That's an

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extraordinarily rare natural experiment

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because

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Avery: normally a fresh moon crater just appears.

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And you're working backwards.

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Anna: Right here we get to work forwards.

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NASA's Lunar Reconnaissance Orbiter can

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photograph the site before and after. And

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because Bill Gray can hand the orbiter team a

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pinpoint, they'll know precisely where to

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look for the new scar. That before and after

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pair is gold for understanding how

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craters actually form and how the lunar

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surface throws material around.

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Avery: And um, there's a whole observing campaign

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around it too.

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Anna: I gather there is a paper with

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something like two dozen authors is

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coordinating professional and amateur

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observers to try and catch the ejecta

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plume, the spray of debris thrown up at the

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moment of impact. Now I want to be careful

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here because this feeds straight into our

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sky. Watch later. You are not going to see a

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flash with your eyes. The impact is on sunlit

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ground near the day night line on the Moon's

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western limb. The plume is a long shot even

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for advanced amateurs with serious

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instruments.

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Avery: But timing wise, who's best placed?

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Anna: Americas north and south? For North

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American listeners, it's about 2:35 in the

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morning. Eastern pre dawn moon well up in the

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west will give Southern hemisphere viewers

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the honest picture in the skywatch, because

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from here in Sydney, the Moon is actually

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below the horizon at impact.

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Avery: Ana, uh, can we talk about the uncomfortable

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part of this? Because a rocket hitting the

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Moon by accident is a great story, but it's

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also a warning, isn't it?

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Anna: It really is, and I'm glad you raised it.

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This is only the second time we've ever

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documented an uncontrolled rocket body

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hitting the Moon. The first left a pair of

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craters on the far side back in 2022.

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Two in a few years. And as commercial

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lunar traffic ramps up toward permanent Moon

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based plans later this decade, the amount of

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hardware drifting around in cislunar space,

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the region between Earth and the Moon is only

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going up.

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Avery: And unlike low Earth orbit, there's really no

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rulebook out there that's the crux.

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Anna: In low Earth orbit, we at least have debris

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coordination guidelines for CIS lunar space.

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There is no equ international framework,

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no agreed way to track, catalog or safely

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dispose of these stages. Longtime

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listeners will remember we covered a study

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just last week on debris in distant

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retrograde orbits around the moon and how it

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becomes a hazard as traffic grows. This

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impact is that abstract worry made

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suddenly, literally concrete.

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Avery: Interestingly, the industry does seem to be

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learning. I read that a more recent SpaceX

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upper stage was deliberately parked in a long

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term solar orbit rather than left wander.

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Anna: That's right. A commercial choice, though not

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a regulation. Which is rather the point.

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So tomorrow morning, when a lost rocket

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finally comes home to the moon, it's worth

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holding two thoughts at once. It's a rare

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and valuable science opportunity. And it's

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a small, bright flag planted on a problem we

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haven't solved yet.

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Avery: One crater, two lessons. Beautifully put.

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Speaking of ancient scars, shall we go and

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look at some far older wreckage?

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Anna: Let's over to you go out to

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Avery: the cold edge of the solar system, to

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Neptune, and you find a little family of

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small inner moons huddled just outside the

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planet's rings. Voyager 2 spotted most of

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them on its one and only Flyby back in

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1989. And ever since they've been too small

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and too far to really study. Until the James

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Webb Space Telescope turned its spectrograph

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on them.

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Anna: And this is a Caltech team, Mike Brown's

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group, the Pluto Killer, himself. Led by

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Riley Davis?

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Avery: The very same. And what they found genuinely

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startled them in the light from three of

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those moons, Larissa, Galatea and Proteus.

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And in the rings, they detected clay

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minerals, specifically magnesium rich

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phyllosilicates.

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Anna: Clay in the outer solar system? Why is

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that such a shock?

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Avery: Because phyllosilicates had never been seen

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anywhere out there beyond Jupiter. And

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crucially, clays only form in the presence of

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liquid water, as Davis put it. It was

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simply not on their list of things to look

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for. It hit them in the face. You don't make

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these minerals on a tiny cold moonlet. You

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make them deep inside a much larger world

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with liquid water in its guts.

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Anna: Though, uh, the material is telling you it

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came from somewhere bigger, somewhere that no

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longer exists.

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Avery: That's the whole story in one sentence. The

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leading explanation is dramatic. Neptune

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once had its own orderly system of moons,

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much like Uranus does today. And then

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Triton arrived.

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Anna: Triton being Neptune's giant backwards

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orbiting moon.

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Avery: Right. And the smoking gun is that

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backwards orbit Triton almost certainly

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didn't form At Neptune. It's a captured

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Kuiper Belt object, a big icy world

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that wandered in from further out and got

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gravitationally snared. And the process

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of capturing something that large would have

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been catastrophic for whatever moons were

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already there. It would have scattered and

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shattered the original family.

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Anna: And these little inner moons are the

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Avery: reassembled shrapnel rubble from the

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interiors of those destroyed worlds

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exposed by the smashup. Some of it drifting

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back together into the moonlets we see now.

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Davis called it, seeing the fingerprints left

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behind by that process. There's even a neat

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consistency check. The largest of the three,

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Proteus, doesn't show the clays. And the

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team think it's because it's big enough to

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have reheated and reprocess itself after

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reforming, hiding its past better than its

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smaller siblings.

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Anna: That's a lovely detail. The biggest one is

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the best at, uh, covering its tracks. And it

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ties us right back to the top of the show,

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doesn't it? A crater tomorrow, a demolished

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moon system billions of years ago. Same

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violence, wildly different scale.

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Avery: The solar system builds by breaking things.

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And it means the next spacecraft we sent out

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there and an ice giant mission is a top

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priority whenever it happens would be flying

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to a, uh, genuine crime scene.

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Anna: Now to the most famous impact of them all.

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And a new twist on how it actually did its

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killing. 66 million years ago, a

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roughly 10 kilometer asteroid struck what's

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now the Yucatan Peninsula. And the age of the

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dinosaurs ended. The long standing picture is

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a slow death. Dust and soot blot out the sun.

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An impact. Winter sets in, food webs

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collapse over months and years.

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Avery: The years of darkness story, which is grim

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but slow.

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Anna: Right? But this new study out of Purdue,

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Brandon Johnson and colleagues in the Journal

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of Geophysical Research argues the very

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first few hours may have been far more brutal

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than we thought. Their headline essentially

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is that exposed animals could have been

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charbroiled within hours.

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Avery: Charbroiled being the technical term.

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Anna: Fair enough. Here's the mechanism. The

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impact vaporized an enormous amount of rock

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and flung it skyward. Some of that cooled

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into tiny glassy beads, spherules,

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which rained back down. And the friction of

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all that debris re entering the atmosphere

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creates, uh, a global heat pulse. That part

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we knew. But earlier models suggested the

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heat pulse, while nasty, might not be enough

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to set the whole planet alight.

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Avery: So what did this team add?

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Anna: Dust. Not the beads, the ultra fine

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stuff. A huge quantity of rock vapor never

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condensed into spherules. It stayed as

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microscopic dust high in the atmosphere. And

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when they put that dust layer into their

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simulations. It acted like an insulating

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blanket, trapping the heat from all those

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falling particles and radiating it down.

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Their number is striking surface heating

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about three and a half times more intense

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than the beads alone.

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Avery: Enough to.

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Anna: Enough, they argue, to ignite spontaneous

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wildfires around the world and kill

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exposed thin skinned animals within the first

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hour or two. Johnson's line was that you're

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essentially in the realm of killing off

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almost everything in that first window.

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Avery: So who survived that?

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Anna: Uh, exactly the ones you'd guess. Anything

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sheltering underground or underwater had a

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fighting chance. Which starts to explain the

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winners and losers pattern of that

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extinction. And then this is the elegant

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part. The same dust that cooked the surface

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in hour one goes on to block sunlight

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for years afterward. So it doesn't replace

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the impact winter idea. It bolts a

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ferocious opening act onto the front of it.

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Avery: I do want to flag the honest caveat though,

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please.

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Anna: And it's an important one. The clearest

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physical evidence for these global wildfires

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so far is really only found in North American

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rocks. A researcher not involved in the

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study, Alfio Chiarenza at University College

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London, made the fair point that we may

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eventually find a truly global fire record,

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but we just don't have it yet. So a

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compelling model, strong regional evidence,

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and a, uh, genuinely open question about how

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planet wide those first hour fires really

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were.

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Avery: And the Throughline Today show writes itself

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the same basic physics that'll carve a modest

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hole in the moon tomorrow. Scaled up is what

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reset life on Earth.

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Okay, moving on. Let's pull all the way back

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now from one new crater to nearly 2 million

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cosmic objects. The Erocita X ray

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telescope on the Spectrum Ringen Gamma

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mission has just put out its second big

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public data release, Dr. 2 and it is

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a genuine landmark for the high energy sky X

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Anna: rays, meaning the violent universe.

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Avery: The hot stuff, the hot, the violent,

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the extreme. Growing black holes,

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exploded stars, million degree gas between

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galaxies. Erocita scans the entire

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sky every six months and this release stacks

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the first three of those all sky scans

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together. The result, around 1.9

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million point like sources, things like stars

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and supermassive black holes, plus about

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64,000 extended sources, which are things

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like galaxy clusters and supernova remnants.

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Anna: Put that number in perspective for me.

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Avery: Happily. The previous great all sky X ray

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survey was ROSAT. Back in the early 1990s,

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it cataloged around 130,000 sources

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and that was the field's benchmark for 30

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years. Hirosita's first release already

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blew past it. Dr. 2 roughly doubles that

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again as the lead author, Miriam Ramos

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Ceja at the Max Planck Institute put it Every

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extra scan drags fainter sources up out of

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the noise.

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Anna: And there's a specific old mystery. This

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cracks, isn't there?

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Avery: There is and I love this one. For about 30

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decades we've known the flat disk of our own

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galaxy glows faintly in X rays. The

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galactic ridge, X ray emission. Without being

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able to prove source by source what's

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producing it, Dr. 2 delivers the first

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direct census of a population of cataclysmic

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variables, close binary stars where a dense

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white dwarf is pulling material off a

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companion. And it turns out there are enough

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of them to account for that mysterious glow.

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A 30 year puzzle resolved by sheer

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completeness.

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Anna: Though it's not one headline discovery, it's

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ah, a map good enough to answer questions we

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couldn't even properly ask before.

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Avery: That's exactly it. And it lands alongside a

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huge Sloan Digital Sky Survey data release.

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So a couple of hundred thousand of these X

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ray sources now have optical fingerprints and

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distances, which lets astronomers map growing

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black holes in three dimensions across cosmic

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time. Its infrastructure for a decade of

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discovery.

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Anna: From a single rooftop sized crater to

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a three dimensional map of the hot universe.

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Not a bad range for one episode.

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Avery: Let's move on to today's skywatch. Both

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hemispheres.

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Anna: Right? Let's take all this upward and outward

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and bring it to your own sky. And we start

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of course with tomorrow's morning's impact.

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Avery: The honest expectations version.

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Anna: The honest version. To be clear, this is

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not a naked eye event. There's no flash to

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see if you're a serious amateur in the

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00:15:42.800 --> 00:15:45.680
Americas with a large telescope and a lot of

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patience. The ejectiplume is a long

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shot target near the Moon's western limb

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around 6:35 universal time.

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That's about 2:35 eastern for north

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America, Moon high in the west for

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everyone else. The real payoff comes later

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when the Lunar Reconnaissance Orbiter returns

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00:16:05.520 --> 00:16:08.380
before an after images of the fresh crater.

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And from here in the southern hemisphere in

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Sydney, the Moon is below the horizon at

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impact time. So this one's an after the fact

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00:16:16.740 --> 00:16:19.340
story for us. Watch for those orbiter

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00:16:19.340 --> 00:16:20.500
images now.

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Avery: The one I'm genuinely excited about, the

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Anna: comet, Comet 10P Tempel 2.

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00:16:26.220 --> 00:16:29.100
It rounded the sun on the 2nd of August and

397
00:16:29.100 --> 00:16:31.740
made its closest pass by Earth on the 3rd.

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About 0.41 astronomical

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00:16:34.940 --> 00:16:37.450
units, roughly 62 million

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00:16:37.450 --> 00:16:40.250
kilometers. So right now it's near its best,

401
00:16:40.330 --> 00:16:43.330
around 8th to 9th magnitude. That's

402
00:16:43.330 --> 00:16:46.210
not naked eye. Think large binoculars

403
00:16:46.210 --> 00:16:49.090
or a small telescope from A dark site, a

404
00:16:49.090 --> 00:16:51.850
small fuzzy patch near the globular cluster

405
00:16:52.010 --> 00:16:54.850
M M30 in Capricornus. But here's why

406
00:16:54.850 --> 00:16:57.690
it matters. This is expected to be Tempel

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00:16:57.690 --> 00:17:00.370
2's finest return for the rest of the

408
00:17:00.370 --> 00:17:00.810
century.

409
00:17:01.220 --> 00:17:03.620
Avery: And this one actually favors us in the south.

410
00:17:03.780 --> 00:17:06.180
Anna: It does a nice one for our Southern

411
00:17:06.180 --> 00:17:08.700
Hemisphere listeners, where the comet climbs

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00:17:08.700 --> 00:17:10.980
higher and sits up for much of the night.

413
00:17:11.460 --> 00:17:13.820
Northern Hemisphere friends you can catch it

414
00:17:13.820 --> 00:17:16.500
too. But it stays low over your southern

415
00:17:16.500 --> 00:17:19.420
horizon, so you'll want a clear flat sky

416
00:17:19.420 --> 00:17:22.220
in that direction. Your darkest window opens

417
00:17:22.220 --> 00:17:24.580
on the nights around the seventh and eighth,

418
00:17:24.580 --> 00:17:26.740
once the waning moon is out of the way.

419
00:17:27.019 --> 00:17:29.019
Avery: Anything for the early evening crowd who

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00:17:29.019 --> 00:17:31.099
don't fancy a midnight comet hunt?

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00:17:31.179 --> 00:17:34.019
Anna: Yes, look west after sunset tonight

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00:17:34.019 --> 00:17:36.859
and you'll find brilliant Venus threaded

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00:17:36.859 --> 00:17:39.019
neatly between two bright stars,

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00:17:39.179 --> 00:17:41.880
Regulus, the heart of Leo and Spica,

425
00:17:41.880 --> 00:17:44.459
uh, in Virgo, a lovely easy

426
00:17:44.459 --> 00:17:46.899
lineup for both hemispheres. No equipment

427
00:17:46.899 --> 00:17:49.499
needed and if you're an early riser.

428
00:17:49.659 --> 00:17:52.579
Mercury reached its best morning showing on

429
00:17:52.579 --> 00:17:55.179
the second and is still hanging low in the

430
00:17:55.179 --> 00:17:58.020
pre dawn east. Catch it before the twilight

431
00:17:58.020 --> 00:17:58.700
drowns it out.

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00:17:58.780 --> 00:18:01.020
Avery: And then the big one. Mark the calendar.

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00:18:01.020 --> 00:18:03.900
Anna: The 12th of August, an enormous

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00:18:03.900 --> 00:18:06.780
day. A total solar eclipse sweeps

435
00:18:06.780 --> 00:18:09.500
across Greenland, Iceland and Spain,

436
00:18:09.740 --> 00:18:12.380
Earth's first totality in more than two

437
00:18:12.380 --> 00:18:15.020
years. And on the very same day, the

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00:18:15.020 --> 00:18:17.740
Perseid meteor shower peaks under a new

439
00:18:17.740 --> 00:18:20.180
moon sky, which is about as good as the

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00:18:20.180 --> 00:18:23.020
perseids ever get. Plus a 6

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00:18:23.100 --> 00:18:25.870
planet alignment. We'll build up to all of it

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00:18:25.870 --> 00:18:28.790
over the coming episodes. And the essential

443
00:18:28.790 --> 00:18:30.990
safety note, which we will repeat every

444
00:18:30.990 --> 00:18:33.870
single time. A total solar eclipse is

445
00:18:33.870 --> 00:18:36.550
only safe to watch with your unaided eyes

446
00:18:36.630 --> 00:18:39.510
during the brief moments of totality itself.

447
00:18:39.990 --> 00:18:42.830
Any other time and everywhere outside the

448
00:18:42.830 --> 00:18:45.430
narrow path of totality, you must use

449
00:18:45.510 --> 00:18:47.270
certified ISO

450
00:18:47.510 --> 00:18:50.470
123122

451
00:18:50.710 --> 00:18:53.270
eclipse. Uh, glasses or a, ah, proper solar

452
00:18:53.270 --> 00:18:55.990
filter. Ordinary sunglasses will not

453
00:18:55.990 --> 00:18:58.470
protect your eyes. Please look after them.

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Avery: Couldn't agree more. A spectacular sky ahead.

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00:19:01.430 --> 00:19:04.070
Watched safely. And that's our lot for today.

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Impacts large, small, ancient and brand new.

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Anna: If today's show sparked something, come and

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00:19:10.270 --> 00:19:13.030
find us at astronomydaily IO

459
00:19:13.350 --> 00:19:16.270
you can stream every back episode. Follow

460
00:19:16.270 --> 00:19:19.110
our continually updating Space News feed,

461
00:19:19.190 --> 00:19:22.110
Leave us a review, drop us a note and sign up

462
00:19:22.110 --> 00:19:24.670
for the daily newsletter. So the cosmos lands

463
00:19:24.670 --> 00:19:25.430
in your inbox

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00:19:25.430 --> 00:19:27.410
Avery: each morning, Find us on social

465
00:19:27.410 --> 00:19:30.010
astrodaily pod and tell a

466
00:19:30.010 --> 00:19:32.530
stargazing friend. Word of mouth is how this

467
00:19:32.530 --> 00:19:33.490
little show grows.

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Anna: We are back tomorrow and if you're in the

469
00:19:35.770 --> 00:19:38.690
Americas with a big scope and an early alarm

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00:19:38.850 --> 00:19:41.730
best of luck chasing that plume. Until then,

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From Anna and M. Avery, clear skies.