Space Mechanic | Today's Space News

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Anna: Somewhere above your head right now, about

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36,000 km up,

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there is a graveyard shift going on.

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Hundreds of satellites still working,

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still useful, and slowly running out of

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fuel.

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Avery: And as of last night, there is finally a

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mechanic on the way.

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Anna: Good evening and welcome to Astronomy Daily.

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I'm Anna.

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Avery: And I'm Avery. Coming up, a spacecraft

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with arms launches on a mission to keep other

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spacecraft alive. A rocket stage is two

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weeks out from hitting the moon and

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astronomers have just put out a call to arms

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about it.

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Anna: We've got two stars that were born together,

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lived together and then died in sequence,

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leaving behind the first pair of

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supernova remnants ever traced back to

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a single binary.

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Avery: The first complete magnetic map of a galaxy

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cluster, an asteroid breakup that may have

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bombarded three worlds and helped freeze our

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own.

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Anna: And a sky watching window that is closing

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faster than you'd like.

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Avery: Let's get into it.

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Anna: So Avery, here's a problem that has quietly

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bothered the satellite industry for about

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60 years. You build a satellite, you

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spend hundreds of millions of dollars on it.

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You put it in geostationary orbit

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35,786

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km up where it hovers

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over the same patch of ground forever. And

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it works beautifully for 15 years

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and then it runs out of fuel.

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Avery: And um, that's, uh, it. The hardware is fine.

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Anna: The hardware is often perfectly fine. The

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cameras work, the transponders work, the

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solar panels work. But without propellant,

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it can't hold its position. So it drifts

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and it becomes junk. You throw away a

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working satellite because the tank is empty.

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Avery: That is a spectacularly wasteful way to run

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an industry.

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Anna: It is. And last night, Northrop

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Grumman launched the most serious attempt yet

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to fix it. At 05:15 in the

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evening Eastern Time on Tuesday 21st

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July, the Falcon 9 lifted

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off from Space Launch Complex 40 at

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Cape Canaveral carrying the Mission Robotic

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Vehicle plus three Mission Extension

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pods.

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Avery: Mission robotic vehicle. What does it

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actually look like?

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Anna: Picture a satellite bus with two

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arms, two robotic arms, each

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about 3 meters long,

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built by the United States Naval Research

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Laboratory and supplied through DARPA's

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Robotic Servicing of Geostationary

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Satellite program.

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Avery: So this is a genuinely dexterous machine, not

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just the tug that bolt on.

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Anna: That's the distinction that matters. The MRV

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can inspect, it can relocate, it can

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repair, it can upgrade. And its

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headline job on this mission is to pick up

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those three mission extension pods and

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install them on client satellites that are

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running low on propellant.

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Avery: So the pods are the actual fuel solution.

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Anna: Think of them as jetpacks. Each pod

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clamps onto a satellite and takes over orbit

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control and momentum management. Using

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electric propulsion, each one can handle a

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satellite of about 2,000kg.

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That's a typical big geostationary bird

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and give it up to eight more years of life.

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Avery: Eight years on a satellite that was

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otherwise finished.

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Anna: Eight years. And the MRV M itself

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carries something called a ah, Passive

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Refueling Interface, which is the first

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refueling interface approved by the US

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Space Force. So the servicer is

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itself designed to be refueled later.

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Avery: Now, Northrub have done a version of this

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before, haven't they?

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Anna: They have, and this is why they're the ones

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doing it. Mission extension vehicle 1

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launched in October 2019, the

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first commercial satellite servicing

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spacecraft ever. And four months later, it

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docked with communications satellite

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Intelsat 901 in geostationary

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orbit. MEV 2 followed in

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August 2020.

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Avery: So what's different this time?

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Anna: Those earlier vehicles were one to one.

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One servicer went to one satellite, docked

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with it, and stayed there doing the work

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itself. The MRV is one to

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many. It carries pods, installs them,

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and moves on. It's the difference between a

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tow truck that has to stay attached to your

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car forever and. And a mechanic who fits a

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new part and drives off to the next job.

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Avery: That scales.

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Anna: That scales. And there's a nice detail on

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the launch itself. The Falcon 9 booster

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B1069 was flying its

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32nd mission and it was

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deliberately expended. No landing.

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Avery: Why give up a booster with 31 flights on it?

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Anna: Because geostationary transfer orbit is

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demanding. Getting that much mass that

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high needed every bit of performance the

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rocket had, and there wasn't propellant left

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for a landing burn. SpaceX made the trade.

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Avery: So when does the actual servicing start?

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Anna: Not for a while. The MRV and the three

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pods each separate and then climb to

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geostationary orbit under their own

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solar electric propulsion. And that

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climb takes up to a year. Servicing

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operations are expected to begin in

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2027. After the initial checkouts,

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the RSGS program gets handed over to

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the US Space Force.

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Avery: A year of just going up slowly

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and efficiently.

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Anna: Electric propulsion is patient. And at the

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end of it, for the first time, there's a

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repair capability parked permanently in

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the most valuable orbital real estate we

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have.

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Avery: Right from a machine built to preserve

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spacecraft to a spacecraft that is about to

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be very thoroughly destroyed.

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Anna: This is one we've been tracking.

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Avery: It is, and I want to be upfront about that.

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We covered this back in June in episode

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125. But there is a genuine reason

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to come back to it, because the science

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community has just done something about it.

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The short version for anyone joining us

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since. In January 2025,

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a Falcon 9 launched two commercial

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lunar landers, Firefly's Blue Ghost

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and ispace's Hakuto R mission

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2. It did its job, but the upper

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stage, cataloged as

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2025010 d

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never came home. Instead of burning up in our

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atmosphere, it ended up in a long looping

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orbit through the Earth Moon system. And

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somebody noticed.

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Anna: The independent astronomer Bill Gray, who

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runs Project Pluto and tracks this sort of

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high orbit debris. His software flagged an

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impact on the 5th of August. This year

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that stage hits the Moon.

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Avery: So what's new? Three things. First, a

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new preprint has just gone up on Arxiv and it

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is signed by 23 astronomers. It is

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essentially a call to arms. They're asking

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the scientific community, professional and

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amateur, to point everything they've got at

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the moon on the 5th of August.

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Anna: Because this is a rare thing, because

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Avery: we almost never get this. We get natural

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impacts on the Moon all the time, but we

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don't know when they're coming here. We know

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the object, we know its mass, we know its

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structure, we know its velocity and we know

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the time to within about a second. That is an

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artificial impact experiment we didn't have

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to pay to set up.

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Anna: And the timing has been tightened, hasn't it?

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Avery: That's a second u, uh, thing. Gray's latest

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published calculation, dated the 17th of July

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puts the impact at 6, 34 and

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32 seconds UTC. Earlier coverage

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back in May was quoting 644.

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So if you've got the old number written down,

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update it am the third. The third is

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the actual physics prediction and this is the

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part I find genuinely interesting. The paper

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models what happens on contact. This thing

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is roughly 12 meters long and about

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4,000 kilograms and crucially, it's

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hollow. It's a tank. So the

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prediction is that it crushes rather than

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punching deep like a can

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Anna: rather than a bullet.

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Avery: Exactly like a can. And the result of

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that is a relatively shallow crater. They're

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estimating 20 to 30 meters across, but a

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a very large ejecta plume,

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kilometers of debris thrown up off the

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surface.

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Anna: So the plume might be the visible part.

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Avery: That's the hope, and it's a subtle bit of

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reasoning. The impact site is near the crater

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Einstein right on the moon's western limb,

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about the 10 o' clock position on the disk.

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As you look at it now, that's awkward because

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it's on the sunlit part of the surface and no

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impact Flash, artificial or natural,

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has ever been recorded on the lit face of the

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Moon.

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Anna: The glare defeats you, but being on the limb

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helps.

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Avery: Being on the limb might save it, because

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rocks thrown up from a site that close to the

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edge rise off the Moon entirely. And

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once they're off the limb, they're

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silhouetted against black sky, catching

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sunlight. So you might not see the flash, but

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you might see the plume.

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Anna: Who else is watching?

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Avery: NASA's Lunar Reconnaissance Orbiter will

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image the site before and after, which gives

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a clean comparison. And South Korea's

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Pathfinder Lunar Orbiter is going to attempt

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to observe as well. There's precedent for the

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afterimage too. When a Chinese rocket stage

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hit the far side in 2022, LRO

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found the site and it had made not one

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crater, but two.

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Anna: And there's a longer term payoff to

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Avery: all this, and this is why the paper matters.

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Beyond the spectacle, they want to test a

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method for pinpointing exactly where an

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object strikes the Moon using the

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observations. If you can nail that down

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against a known impact, you've validated a

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technique. And that feeds directly into

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planning seismic experiments on the lunar

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surface for future missions.

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Anna: Now the practical question, who actually gets

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to see this?

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Avery: And, um, this is where our North American

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listeners want to pay attention, because this

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one is squarely yours.

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6:34 UTC on the 5th of August

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is 29 minutes past 2 in the morning, Eastern

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Time. 1:34 Central,

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12:34 Mountain. And on the west coast

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it's still the night before. 11:34 in the

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evening on the 4th,

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Anna: middle of the night, but the Moon is well up.

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Avery: The Moon is well placed across the continent,

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and the paper specifically identifies

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observers in the Americas as the ideal group.

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If you have a telescope and you've ever

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wanted to contribute to something real, this

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is the night they are explicitly asking

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amateurs to take part.

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Anna: And for those of us further around the globe,

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less kind.

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Avery: And I'll be straight about it. For us In

266
00:10:58.450 --> 00:11:01.130
Australia, that's 4:34 in the afternoon,

267
00:11:01.210 --> 00:11:04.170
broad daylight, New Zealand early evening,

268
00:11:04.250 --> 00:11:07.250
no good either. The UK and Europe get half

269
00:11:07.250 --> 00:11:09.210
past seven in the morning, which is also

270
00:11:09.210 --> 00:11:11.890
daylight. So the live event belongs to the

271
00:11:11.890 --> 00:11:14.570
Anna: Americas, but the aftermath belongs to

272
00:11:14.570 --> 00:11:14.890
everyone.

273
00:11:15.290 --> 00:11:17.850
Avery: The aftermath belongs to everyone. The

274
00:11:17.850 --> 00:11:20.530
LRO before and after imagery, the crater

275
00:11:20.530 --> 00:11:23.090
measurements, the analysis of how well the

276
00:11:23.090 --> 00:11:25.400
predictions held up, and frankly, the

277
00:11:25.400 --> 00:11:27.400
question sitting underneath all of this is

278
00:11:27.400 --> 00:11:29.760
global. We are about to start putting people

279
00:11:29.760 --> 00:11:32.600
back on the Moon and we are currently hitting

280
00:11:32.600 --> 00:11:35.360
it with our own rubbish by accident, without

281
00:11:35.360 --> 00:11:35.840
warning.

282
00:11:36.000 --> 00:11:38.960
Anna: Alright, Avery, moving on to our next story.

283
00:11:39.600 --> 00:11:42.440
More than Half of all stars are in multiple

284
00:11:42.440 --> 00:11:45.440
systems, two or more suns orbiting each

285
00:11:45.440 --> 00:11:48.360
other. And for the really massive stars, the

286
00:11:48.360 --> 00:11:51.320
ones destined to explode, that fraction is

287
00:11:51.320 --> 00:11:52.080
even higher.

288
00:11:53.000 --> 00:11:55.240
Avery: So most supernovae should have had a sibling.

289
00:11:55.640 --> 00:11:58.280
Anna: That is exactly the implication. And yet,

290
00:11:58.360 --> 00:12:01.320
until this week, astronomers had never found

291
00:12:01.320 --> 00:12:03.960
a single case where both stars in a binary

292
00:12:03.960 --> 00:12:06.960
exploded and both left behind remnants we

293
00:12:06.960 --> 00:12:07.640
can still see

294
00:12:08.040 --> 00:12:09.960
Avery: not one out of how many.

295
00:12:10.280 --> 00:12:13.000
Anna: We've cataloged around 300 supernova

296
00:12:13.000 --> 00:12:15.760
remnants in our galaxy. Not one confirmed

297
00:12:15.760 --> 00:12:18.120
sibling pair. And the reason is a bit

298
00:12:18.120 --> 00:12:20.420
embarrassing, actually. One of them was

299
00:12:20.420 --> 00:12:22.580
probably sitting in plain sight the whole

300
00:12:22.580 --> 00:12:22.860
time.

301
00:12:23.180 --> 00:12:23.820
Avery: Go on.

302
00:12:24.060 --> 00:12:25.740
Anna: The Jellyfish Nebula

303
00:12:25.820 --> 00:12:28.220
IC443 in the

304
00:12:28.220 --> 00:12:30.940
constellation Gemini, about 6,000

305
00:12:30.940 --> 00:12:33.420
light years away. It is one of the best

306
00:12:33.500 --> 00:12:36.380
studied supernova remnants in the sky and

307
00:12:36.380 --> 00:12:38.700
one of the brightest gamma ray sources of its

308
00:12:38.700 --> 00:12:41.540
kind. If you could see it with your eye, it

309
00:12:41.540 --> 00:12:43.500
would look bigger than the full Moon.

310
00:12:43.900 --> 00:12:46.300
Avery: And, um, something was hiding behind it.

311
00:12:46.740 --> 00:12:49.300
Anna: Next to it, there's a much fainter object

312
00:12:49.380 --> 00:12:51.553
called G189 6

313
00:12:51.740 --> 00:12:54.460
3. It was first picked up in

314
00:12:54.460 --> 00:12:57.100
1994 by the German ROSAT

315
00:12:57.100 --> 00:12:59.700
satellite as a faint X ray glow.

316
00:12:59.860 --> 00:13:02.300
And later the Russian German spectrum

317
00:13:02.300 --> 00:13:05.260
Rontgen Gamma Observatory saw shell like

318
00:13:05.260 --> 00:13:07.780
structures in it, which suggested it was also

319
00:13:07.860 --> 00:13:10.820
a supernova remnant. But it sits right

320
00:13:10.820 --> 00:13:13.460
up against the glare of the jellyfish, and

321
00:13:13.460 --> 00:13:14.980
that glare drowns it.

322
00:13:15.530 --> 00:13:17.610
Avery: So how did they finally separate them?

323
00:13:18.010 --> 00:13:20.970
Anna: 16 years of data from NASA's Fermi

324
00:13:20.970 --> 00:13:23.810
Gamma Ray Space Telescope. The team led

325
00:13:23.810 --> 00:13:26.130
by Miltiades Michaelides, a

326
00:13:26.130 --> 00:13:29.010
postdoctoral fellow at Stanford, essentially

327
00:13:29.010 --> 00:13:31.850
subtracted the jellyfish out, isolated

328
00:13:31.850 --> 00:13:34.410
its gamma ray emission and looked at what was

329
00:13:34.410 --> 00:13:35.210
left underneath.

330
00:13:35.770 --> 00:13:37.210
Avery: And, um, there was something left.

331
00:13:37.370 --> 00:13:38.770
Anna: There was G

332
00:13:38.770 --> 00:13:41.610
189.63 is

333
00:13:41.610 --> 00:13:44.210
independently producing gamma rays. Which

334
00:13:44.210 --> 00:13:47.040
matters enormously because gamma rays mean

335
00:13:47.270 --> 00:13:49.430
particle acceleration, and particle

336
00:13:49.430 --> 00:13:51.910
acceleration is what a supernova remnant

337
00:13:51.910 --> 00:13:54.390
does. It's the shock wave doing work.

338
00:13:54.550 --> 00:13:56.950
Avery: Mikhail Adiz had a nice way of putting that,

339
00:13:56.950 --> 00:13:57.510
didn't he?

340
00:13:57.590 --> 00:14:00.470
Anna: He compared it to a drop of water falling on

341
00:14:00.470 --> 00:14:03.390
a still lake. The ripples spread out from

342
00:14:03.390 --> 00:14:06.070
the point of contact. A supernova remnant

343
00:14:06.070 --> 00:14:08.750
does exactly the same thing. And if you can

344
00:14:08.750 --> 00:14:11.350
see the ripples, you know, something dropped.

345
00:14:11.750 --> 00:14:14.310
Avery: So we have two remnants next to each other.

346
00:14:14.670 --> 00:14:16.430
How do we know they're related rather than

347
00:14:16.430 --> 00:14:18.190
just an accident of line of sight?

348
00:14:18.430 --> 00:14:21.270
Anna: This is the elegant part. There's a filament

349
00:14:21.270 --> 00:14:23.750
of gas arcing between them. And that

350
00:14:23.750 --> 00:14:25.750
filament is where the shock wave from

351
00:14:25.750 --> 00:14:28.350
G189.6 3

352
00:14:28.590 --> 00:14:31.230
has slammed into the same molecular cloud

353
00:14:31.310 --> 00:14:33.230
that the jellyfish is pushing against.

354
00:14:33.870 --> 00:14:36.790
Avery: Same cloud so same distance, same

355
00:14:36.790 --> 00:14:37.230
cloud.

356
00:14:37.310 --> 00:14:40.230
Anna: Same distance, same neighborhood. They're not

357
00:14:40.230 --> 00:14:43.030
one in front of the other. They're genuinely

358
00:14:43.030 --> 00:14:45.330
next door to each other. And that's what

359
00:14:45.330 --> 00:14:47.610
makes the shared origin story credible.

360
00:14:48.010 --> 00:14:49.650
Avery: So walk me through the story they're

361
00:14:49.650 --> 00:14:50.170
proposing.

362
00:14:50.410 --> 00:14:52.890
Anna: A tale of two massive stars

363
00:14:52.970 --> 00:14:55.450
born together, gravitationally bound,

364
00:14:55.690 --> 00:14:58.570
orbiting extremely closely, perhaps

365
00:14:58.570 --> 00:15:01.290
only a few times the Earth's sun distance

366
00:15:01.290 --> 00:15:04.250
apart. Close enough that material was likely

367
00:15:04.250 --> 00:15:07.010
flowing from one to the other. And then the

368
00:15:07.010 --> 00:15:09.610
bigger one runs out of fuel and detonates.

369
00:15:09.930 --> 00:15:11.850
Avery: And, um. The explosion breaks the

370
00:15:11.850 --> 00:15:12.490
partnership.

371
00:15:12.920 --> 00:15:15.400
Anna: The explosion breaks the partnership. The

372
00:15:15.400 --> 00:15:17.960
binary is disrupted and the surviving

373
00:15:17.960 --> 00:15:20.840
companion is essentially kicked flung

374
00:15:20.840 --> 00:15:23.680
off through the galaxy on its own. It keeps

375
00:15:23.680 --> 00:15:26.040
traveling, and tens of thousands of years

376
00:15:26.040 --> 00:15:27.960
later, it explodes too.

377
00:15:28.200 --> 00:15:29.800
Avery: How far apart did they end up?

378
00:15:30.120 --> 00:15:32.960
Anna: The centers of the two explosions are now

379
00:15:32.960 --> 00:15:35.640
somewhere between 30 and 50 light years

380
00:15:35.640 --> 00:15:38.480
apart. Two stars that were once close enough

381
00:15:38.480 --> 00:15:41.410
to be exchanging material, now separated

382
00:15:41.410 --> 00:15:44.250
by that gap. And each marked by its own

383
00:15:44.250 --> 00:15:45.490
expanding shell.

384
00:15:45.730 --> 00:15:46.530
Avery: What were they?

385
00:15:46.690 --> 00:15:49.290
Anna: The jellyfish's progenitor is thought to have

386
00:15:49.290 --> 00:15:52.170
been something like 15 to 25 times

387
00:15:52.170 --> 00:15:55.010
the mass of the Sun. Its companion at

388
00:15:55.010 --> 00:15:57.850
least 20. Both were probably tens

389
00:15:57.850 --> 00:16:00.250
of thousands times more luminous than the

390
00:16:00.250 --> 00:16:02.850
sun. And both may now be neutron

391
00:16:02.850 --> 00:16:03.330
stars.

392
00:16:03.570 --> 00:16:05.770
Avery: And, um, publication status because I know

393
00:16:05.770 --> 00:16:07.250
this was previewed at a conference.

394
00:16:07.760 --> 00:16:10.560
Anna: Good flag. Miltiais presented the results at

395
00:16:10.560 --> 00:16:13.080
the American Astronomical Society meeting in

396
00:16:13.080 --> 00:16:15.840
Pasadena back in June. What's happened this

397
00:16:15.840 --> 00:16:18.200
week is the peer reviewed paper. It's in

398
00:16:18.200 --> 00:16:20.440
Nature communications with the Stanford

399
00:16:20.440 --> 00:16:22.840
release. And wider coverage landing on the

400
00:16:22.840 --> 00:16:23.360
21st.

401
00:16:23.920 --> 00:16:26.440
Avery: And one for our listeners. Can we go and look

402
00:16:26.440 --> 00:16:27.200
at any of this?

403
00:16:27.600 --> 00:16:30.480
Anna: Not this month. Wherever you are. Gemini

404
00:16:30.480 --> 00:16:33.040
is close to the sun at the moment. So it's

405
00:16:33.040 --> 00:16:35.800
lost in the glare globally. But it comes

406
00:16:35.800 --> 00:16:38.160
back. And this is one where Northern

407
00:16:38.160 --> 00:16:40.080
hemisphere listeners get the better deal.

408
00:16:40.480 --> 00:16:43.120
From North America and Europe, Gemini

409
00:16:43.120 --> 00:16:45.360
rides high overhead through winter

410
00:16:45.680 --> 00:16:48.360
December into March. And the jellyfish

411
00:16:48.360 --> 00:16:51.320
sits. Beautifully placed for a telescope or a

412
00:16:51.320 --> 00:16:52.240
long exposure.

413
00:16:52.640 --> 00:16:55.000
Avery: And from down here we still get it.

414
00:16:55.000 --> 00:16:57.920
Anna: Just lower from Australia and New Zealand,

415
00:16:57.920 --> 00:17:00.400
Gemini comes up in the northern sky through

416
00:17:00.400 --> 00:17:02.850
our summer. Visible, worth hunting,

417
00:17:03.010 --> 00:17:06.010
but closer to the horizon. Either way, put

418
00:17:06.010 --> 00:17:08.010
it on the list for the end of the year. And

419
00:17:08.010 --> 00:17:10.890
bear in mind the jellyfish is faint. It would

420
00:17:10.890 --> 00:17:12.930
be bigger than the full moon if your eye

421
00:17:12.930 --> 00:17:15.370
could pick it up. But it needs photography or

422
00:17:15.370 --> 00:17:17.250
a decent aperture to show itself.

423
00:17:17.730 --> 00:17:20.170
Avery: Anna, uh, here's something we know exists but

424
00:17:20.170 --> 00:17:22.050
have never actually been able to draw.

425
00:17:22.690 --> 00:17:24.850
Galaxy clusters. The largest

426
00:17:24.850 --> 00:17:27.050
gravitationally bound structures in the

427
00:17:27.050 --> 00:17:29.660
universe. Hundreds or thousands of

428
00:17:29.660 --> 00:17:32.540
galaxies plus enormous clouds of hot gas,

429
00:17:32.620 --> 00:17:35.300
plus dark matter Are threaded through

430
00:17:35.300 --> 00:17:36.780
with magnetic fields.

431
00:17:37.180 --> 00:17:38.860
Anna: We've known that for decades.

432
00:17:39.180 --> 00:17:41.900
Avery: What we have never done is map the shape of

433
00:17:41.900 --> 00:17:44.580
one across an entire cluster from the

434
00:17:44.580 --> 00:17:46.060
middle right out to the edge.

435
00:17:46.300 --> 00:17:47.820
Anna: And now somebody has.

436
00:17:48.140 --> 00:17:50.940
Avery: A team led by Andrea, uh, Boton at innaf,

437
00:17:51.020 --> 00:17:53.820
Italy's National Astrophysics institute, Has

438
00:17:53.820 --> 00:17:56.380
reconstructed the magnetic field of Galaxy

439
00:17:56.380 --> 00:17:59.320
cluster Abell 2255. And I

440
00:17:59.320 --> 00:18:01.600
want to be precise about that name because at

441
00:18:01.600 --> 00:18:03.880
least one outlet has got it wrong this week

442
00:18:03.880 --> 00:18:06.440
and called it Abell 2142.

443
00:18:06.760 --> 00:18:09.240
It is Abell 2255,

444
00:18:09.560 --> 00:18:11.240
about a billion light years away.

445
00:18:11.720 --> 00:18:12.920
Anna: Why that cluster?

446
00:18:13.160 --> 00:18:15.400
Avery: Because it's famously messy in radio.

447
00:18:15.720 --> 00:18:18.600
Abell 2255 has long been known for

448
00:18:18.600 --> 00:18:21.360
its complexity. It's full of strange, diffuse

449
00:18:21.360 --> 00:18:24.280
radio structures, Halos and filaments, which

450
00:18:24.280 --> 00:18:26.240
is exactly what you want if you're trying to

451
00:18:26.240 --> 00:18:28.470
trace magnetic fields, because those

452
00:18:28.470 --> 00:18:31.030
structures are made by energetic electrons

453
00:18:31.030 --> 00:18:32.990
spiraling along magnetic lines.

454
00:18:33.310 --> 00:18:35.470
Anna: So the radio emission is the field

455
00:18:35.630 --> 00:18:37.070
effectively made visible.

456
00:18:37.390 --> 00:18:40.310
Avery: It's the tracer. Electrons corkscrewing

457
00:18:40.310 --> 00:18:42.990
along magnetic lines give off radio waves.

458
00:18:43.230 --> 00:18:45.470
So if you can see the emission finely enough,

459
00:18:45.550 --> 00:18:48.110
you can work backwards to the field. The

460
00:18:48.110 --> 00:18:50.230
problem has always been that these signals

461
00:18:50.230 --> 00:18:52.110
are extraordinarily faint.

462
00:18:52.350 --> 00:18:55.020
Anna: What did they observe with lofar, the

463
00:18:55.020 --> 00:18:57.580
Avery: low frequency array, the European radial

464
00:18:57.580 --> 00:19:00.300
telescope spread across a continent. And

465
00:19:00.300 --> 00:19:02.820
these are the deepest radio observations ever

466
00:19:02.820 --> 00:19:05.660
made of a galaxy cluster that was combined

467
00:19:05.660 --> 00:19:07.660
with a new data analysis technique. And

468
00:19:07.660 --> 00:19:09.540
between them, that's what cracked it.

469
00:19:09.780 --> 00:19:11.140
Anna: And what does the map show?

470
00:19:11.540 --> 00:19:14.300
Avery: This is defining in some regions of the

471
00:19:14.300 --> 00:19:16.580
cluster, the magnetic field lines are

472
00:19:16.580 --> 00:19:19.140
strikingly coherent. They follow very

473
00:19:19.140 --> 00:19:21.620
specific directions stretching radially

474
00:19:21.620 --> 00:19:24.020
outward along the extended radial structures.

475
00:19:24.390 --> 00:19:26.790
Anna: They're not random, which tells you something

476
00:19:26.870 --> 00:19:28.990
made them that way, which tells you

477
00:19:28.990 --> 00:19:31.630
Avery: something is organizing them. And Boton's

478
00:19:31.630 --> 00:19:33.870
conclusion is that the shape of the field is

479
00:19:33.870 --> 00:19:36.270
intimately linked to the motion of the gas it

480
00:19:36.270 --> 00:19:38.790
sits in. The field gets stretched and

481
00:19:38.790 --> 00:19:41.150
compressed by the movements associated with

482
00:19:41.150 --> 00:19:42.710
the cluster's own formation.

483
00:19:43.110 --> 00:19:45.750
Anna: So the cluster assembling itself is what

484
00:19:45.750 --> 00:19:46.950
shapes the magnetism?

485
00:19:47.350 --> 00:19:49.230
Avery: That's the argument, and it's the first

486
00:19:49.230 --> 00:19:51.570
observational evidence of it. The same

487
00:19:51.570 --> 00:19:54.410
violent process that builds a galaxy cluster,

488
00:19:54.570 --> 00:19:57.530
Gas falling in, sloshing, colliding,

489
00:19:57.530 --> 00:20:00.210
merging, is the process that combs the

490
00:20:00.210 --> 00:20:02.650
magnetic field into the pattern we now see.

491
00:20:02.970 --> 00:20:05.610
Anna: And that ties into the radio halos question.

492
00:20:05.930 --> 00:20:08.530
Avery: It does. Bolton says they believe the

493
00:20:08.530 --> 00:20:10.930
mechanism that switches on these gigantic

494
00:20:10.930 --> 00:20:13.610
radio emissions is linked to the formation

495
00:20:13.610 --> 00:20:16.210
process of the clusters themselves. So the

496
00:20:16.210 --> 00:20:18.450
map isn't just a pretty picture. It's the

497
00:20:18.450 --> 00:20:19.770
evidence for the engine.

498
00:20:19.790 --> 00:20:22.460
Anna: The. It's a lovely Example of the thing radio

499
00:20:22.460 --> 00:20:25.180
astronomy does best, showing you a

500
00:20:25.180 --> 00:20:28.060
Avery: structure that is completely invisible, is a

501
00:20:28.060 --> 00:20:30.460
billion light years away, is bigger than

502
00:20:30.460 --> 00:20:32.540
anything else in the universe, and has been

503
00:20:32.540 --> 00:20:35.490
sitting there the entire time. Published in,

504
00:20:35.490 --> 00:20:37.140
uh, Astronomy and Astrophysics.

505
00:20:37.380 --> 00:20:40.140
Anna: Every if you want to know what has hit the

506
00:20:40.140 --> 00:20:41.460
Earth, don't look at

507
00:20:41.460 --> 00:20:43.940
Avery: the Earth because the Earth keeps erasing it

508
00:20:44.180 --> 00:20:44.900
constantly.

509
00:20:45.060 --> 00:20:47.540
Anna: Plate tectonics, volcanism, weather,

510
00:20:47.700 --> 00:20:50.610
water, erosion. Craters get buried,

511
00:20:50.610 --> 00:20:53.530
distorted, subducted, destroyed. The

512
00:20:53.530 --> 00:20:55.730
practical consequence is that geological

513
00:20:55.730 --> 00:20:57.890
evidence for impacts older than about

514
00:20:57.970 --> 00:21:00.410
650 million years is

515
00:21:00.410 --> 00:21:01.810
extremely scarce here.

516
00:21:02.050 --> 00:21:03.810
Avery: And the Moon doesn't do any of that.

517
00:21:03.970 --> 00:21:06.970
Anna: No plate tectonics, no flowing water, no

518
00:21:06.970 --> 00:21:09.650
meaningful atmosphere. The Moon just keeps

519
00:21:09.650 --> 00:21:11.570
the receipts. And when you read those

520
00:21:11.570 --> 00:21:14.010
receipts carefully, there's a spike. When,

521
00:21:14.010 --> 00:21:16.690
uh, around 800 million years ago,

522
00:21:17.100 --> 00:21:19.500
there's a surge in large lunar impacts. And

523
00:21:19.500 --> 00:21:22.460
it shows up in two independent ways. One

524
00:21:22.460 --> 00:21:25.020
is the estimated ages of big craters,

525
00:21:25.020 --> 00:21:27.580
including copernicus, which is 93

526
00:21:27.580 --> 00:21:30.300
kilometers across. The other is impact

527
00:21:30.380 --> 00:21:30.940
glass.

528
00:21:31.340 --> 00:21:33.100
Avery: Explain impact glass.

529
00:21:33.580 --> 00:21:35.900
Anna: When something hits hard enough, the heat

530
00:21:35.900 --> 00:21:38.500
melts. Rock that melt cools into

531
00:21:38.500 --> 00:21:41.340
glass, and the glass locks in a, uh, chemical

532
00:21:41.340 --> 00:21:44.020
timestamp. The Apollo missions brought a lot

533
00:21:44.020 --> 00:21:46.160
of it home. And when you look at the age

534
00:21:46.160 --> 00:21:48.680
distribution of that glass, you see the same

535
00:21:48.680 --> 00:21:50.840
spike at 800 million years.

536
00:21:51.480 --> 00:21:53.840
Avery: So two different methods agree that something

537
00:21:53.840 --> 00:21:55.720
happened, but nobody knew what.

538
00:21:55.960 --> 00:21:58.280
Anna: Nobody knew what. That's the puzzle that's

539
00:21:58.280 --> 00:22:00.480
been sitting there for decades. And a new

540
00:22:00.480 --> 00:22:03.040
paper led by Dr. William Bakke at the

541
00:22:03.040 --> 00:22:05.240
Southwest Research Institute in Boulder

542
00:22:05.400 --> 00:22:08.280
proposes a specific culprit, which is

543
00:22:08.520 --> 00:22:11.320
an asteroid called Eulalia, or rather

544
00:22:11.320 --> 00:22:13.760
the parent body of the family of asteroids we

545
00:22:13.760 --> 00:22:16.520
now call Eulalia. Uh, because the object, its

546
00:22:17.060 --> 00:22:19.780
no longer exists. It was catastrophically

547
00:22:19.780 --> 00:22:22.260
broken apart in a collision in the main belt.

548
00:22:22.500 --> 00:22:24.820
Avery: And the location of that breakup matters.

549
00:22:25.060 --> 00:22:27.900
Anna: The location is everything. It happened right

550
00:22:27.900 --> 00:22:30.700
next to what's called the J3 to one resonance

551
00:22:30.700 --> 00:22:33.019
with Jupiter. And a resonance like that is

552
00:22:33.019 --> 00:22:35.380
essentially a gravitational trapdoor.

553
00:22:35.540 --> 00:22:37.700
Material that wanders into it, gets its

554
00:22:37.700 --> 00:22:40.340
orbit, pumped up by Jupiter and flung into

555
00:22:40.340 --> 00:22:41.460
the inner solar system.

556
00:22:41.940 --> 00:22:44.460
Avery: So the shrapnel had a delivery mechanism

557
00:22:44.460 --> 00:22:45.460
waiting right there.

558
00:22:45.790 --> 00:22:48.390
Anna: It had an open door right next to it. And the

559
00:22:48.390 --> 00:22:51.070
simulations show what happened in two phases.

560
00:22:51.390 --> 00:22:53.230
Half the fragments reached the resonance

561
00:22:53.230 --> 00:22:55.430
almost immediately. That's the prompt

562
00:22:55.430 --> 00:22:58.230
bombardment Planetary shrapnel sprayed across

563
00:22:58.230 --> 00:22:59.310
the inner solar system.

564
00:22:59.710 --> 00:23:01.470
Avery: And, um, the other half, over the

565
00:23:01.470 --> 00:23:04.110
Anna: following 100 to 150 million

566
00:23:04.110 --> 00:23:06.350
years, another quarter of the fragments

567
00:23:06.350 --> 00:23:08.670
drifted into the resonance more slowly,

568
00:23:08.830 --> 00:23:11.110
pushed by something called the Yarkovsky

569
00:23:11.110 --> 00:23:14.100
effect, which is what, in plain terms it's

570
00:23:14.100 --> 00:23:16.940
sunlight doing work. A rotating asteroid

571
00:23:16.940 --> 00:23:19.100
absorbs sunlight on one side and

572
00:23:19.100 --> 00:23:21.980
reradiates that heat as it turns. That

573
00:23:21.980 --> 00:23:24.780
reradiation gives an incredibly gentle

574
00:23:24.780 --> 00:23:27.779
push. On a human scale, it's nothing. Over

575
00:23:27.779 --> 00:23:30.140
a hundred million years, it can move an

576
00:23:30.140 --> 00:23:32.620
asteroid's orbit enough to drop it into a

577
00:23:32.620 --> 00:23:33.340
trapdoor.

578
00:23:33.580 --> 00:23:36.300
Avery: So this wasn't one bad afternoon. This was a

579
00:23:36.300 --> 00:23:37.100
long siege.

580
00:23:37.500 --> 00:23:39.740
Anna: That's the reframing, I think, is genuinely

581
00:23:39.740 --> 00:23:42.700
important here. Not an event, an episode,

582
00:23:42.780 --> 00:23:45.300
a bombardment that opened suddenly and then

583
00:23:45.300 --> 00:23:48.220
kept going for well over 100 million years.

584
00:23:48.700 --> 00:23:50.220
Avery: And what does that mean for Earth?

585
00:23:50.380 --> 00:23:52.580
Anna: Here's the number that changes the scale of

586
00:23:52.580 --> 00:23:55.260
it. For every large impact recorded on the

587
00:23:55.260 --> 00:23:58.060
moon, roughly 20 similar or larger

588
00:23:58.060 --> 00:24:00.500
impacts hit the Earth, where a bigger target

589
00:24:00.500 --> 00:24:01.820
with stronger gravity.

590
00:24:02.140 --> 00:24:03.368
Avery: 20 to 1.

591
00:24:03.481 --> 00:24:06.350
Anna: 20 to 1. So a spike on the Moon

592
00:24:06.350 --> 00:24:09.350
means a barrage down here. And now look

593
00:24:09.350 --> 00:24:11.950
at what else was happening around 800 million

594
00:24:11.950 --> 00:24:14.790
years ago. That is the run up to one of the

595
00:24:14.790 --> 00:24:16.990
most dramatic climate episodes in our

596
00:24:16.990 --> 00:24:19.550
planet's history. Widespread global

597
00:24:19.630 --> 00:24:22.430
cooling and major shifts in the biosphere.

598
00:24:22.830 --> 00:24:24.910
Avery: Is he climbing a causal link?

599
00:24:25.310 --> 00:24:27.950
Anna: He's careful. And I want to be careful too.

600
00:24:28.270 --> 00:24:30.830
Bakke's phrasing is that given the peak of

601
00:24:30.830 --> 00:24:33.390
this barrage coincides with a period of

602
00:24:33.390 --> 00:24:35.970
widespread cooling and major shifts in our

603
00:24:35.970 --> 00:24:38.810
biosphere, it is tempting to suggest the

604
00:24:38.810 --> 00:24:41.490
former produced the latter. That is a

605
00:24:41.490 --> 00:24:44.450
hypothesis flagged as tempting, not a

606
00:24:44.450 --> 00:24:45.050
conclusion.

607
00:24:45.450 --> 00:24:48.330
Avery: Because so far, only one impact has ever

608
00:24:48.330 --> 00:24:51.050
been firmly tied to a biological outcome.

609
00:24:51.369 --> 00:24:54.330
Anna: Pictxulub, 66 million years ago.

610
00:24:54.490 --> 00:24:57.050
The end of the dinosaurs. That's the one.

611
00:24:57.290 --> 00:24:58.890
Everything else is inference.

612
00:24:59.370 --> 00:25:01.290
Avery: So how would you ever test this?

613
00:25:02.040 --> 00:25:04.560
Anna: This is my favorite part of the paper. And

614
00:25:04.560 --> 00:25:06.760
it's the reason to keep an eye on this story.

615
00:25:07.080 --> 00:25:10.040
We have asteroid samples on Earth right now.

616
00:25:10.120 --> 00:25:12.520
Hayabusa2 brought material back from

617
00:25:12.520 --> 00:25:15.520
Ryugu in December 2020. Osiris

618
00:25:15.520 --> 00:25:17.866
Rex brought Bennu back in September

619
00:25:18.014 --> 00:25:20.760
2023. Both are under analysis.

620
00:25:21.240 --> 00:25:23.720
Avery: And if they carry the Eulalia fingerprint,

621
00:25:24.120 --> 00:25:26.880
Anna: if the mineralogy matches the Eulalia

622
00:25:26.880 --> 00:25:29.880
family, then we are holding in a laboratory

623
00:25:30.280 --> 00:25:32.760
physical samples of the material that rained

624
00:25:32.760 --> 00:25:35.700
on solar system 800 million

625
00:25:35.780 --> 00:25:38.620
years ago. That would turn a dynamical

626
00:25:38.620 --> 00:25:41.380
model into a direct compositional record.

627
00:25:41.940 --> 00:25:44.700
Avery: That's a remarkable thought. Brains in a lab

628
00:25:44.700 --> 00:25:47.620
in Japan and Texas. That might be pieces of

629
00:25:47.620 --> 00:25:50.020
the thing that helped freeze the Earth.

630
00:25:50.500 --> 00:25:53.100
Anna: Published in the Planetary Science Journal by

631
00:25:53.100 --> 00:25:55.740
Botke, with Volkerlitsky, Dykhuis and

632
00:25:55.740 --> 00:25:56.260
Zellner.

633
00:25:56.340 --> 00:25:56.740
Avery: Great.

634
00:25:56.740 --> 00:25:58.780
And our next story comes with a deadline.

635
00:25:58.780 --> 00:26:00.340
Wherever in the world you're listening.

636
00:26:00.760 --> 00:26:01.640
Anna: What's the urgency?

637
00:26:01.960 --> 00:26:04.760
Avery: The moon first quarter was yesterday,

638
00:26:04.760 --> 00:26:07.720
the 21st. Tonight it's a waxing

639
00:26:07.720 --> 00:26:10.120
gibbous. And every night from here it gets

640
00:26:10.120 --> 00:26:12.920
brighter and stays up longer, building to the

641
00:26:12.920 --> 00:26:15.800
buck. Moon full at 4:36 in the afternoon

642
00:26:15.880 --> 00:26:18.360
UTC on Wednesday the 29th.

643
00:26:18.680 --> 00:26:21.320
That's 10:36 in the morning Eastern time in

644
00:26:21.320 --> 00:26:23.880
the States and 12:36 on Thursday

645
00:26:23.960 --> 00:26:25.240
morning for us in Australia.

646
00:26:25.960 --> 00:26:28.200
Anna: And that matters because of what's peaking.

647
00:26:28.880 --> 00:26:31.840
Avery: The southern Delta Aquariates peak falls

648
00:26:31.840 --> 00:26:34.440
on the 30th, effectively the same night as

649
00:26:34.440 --> 00:26:36.760
the full moon. So the peak is going to be

650
00:26:36.760 --> 00:26:39.360
washed out, which means the practical advice

651
00:26:39.360 --> 00:26:41.720
is the same for everybody. Don't wait for

652
00:26:41.720 --> 00:26:44.559
peak night. This week is your window in the

653
00:26:44.559 --> 00:26:46.760
small hours while the moon still sets and

654
00:26:46.760 --> 00:26:48.800
leaves you real darkness before dawn.

655
00:26:49.200 --> 00:26:51.360
Anna: And this is a shower that favors us.

656
00:26:51.680 --> 00:26:54.680
Avery: It does. From Australia, New Zealand and

657
00:26:54.680 --> 00:26:57.660
southern Africa, the radiant sits high close

658
00:26:57.660 --> 00:27:00.060
to overhead, which is why the shower gets

659
00:27:00.060 --> 00:27:02.860
underrated. In the north, under genuinely

660
00:27:02.860 --> 00:27:05.780
dark skies, you might see 15 to 20

661
00:27:05.780 --> 00:27:08.780
an hour. And they're lovely meteors. Long,

662
00:27:08.780 --> 00:27:11.340
graceful streaks rather than quick flashes,

663
00:27:11.340 --> 00:27:13.860
and known for persistent trains, those

664
00:27:13.860 --> 00:27:16.100
glowing trails that hang in the air for a

665
00:27:16.100 --> 00:27:17.260
second or two afterwards.

666
00:27:17.740 --> 00:27:19.860
Anna: And northern listeners aren't shut out of

667
00:27:19.860 --> 00:27:22.340
Avery: this one, not at all. And I want to be clear

668
00:27:22.340 --> 00:27:24.420
about that, because this shower gets written

669
00:27:24.420 --> 00:27:27.130
off in the north too readily. If you're in

670
00:27:27.130 --> 00:27:29.530
North America, particularly the southern

671
00:27:29.530 --> 00:27:32.410
states, Texas, Florida, Arizona, the

672
00:27:32.410 --> 00:27:35.130
Gulf coast, the Delta Aquarids are a

673
00:27:35.130 --> 00:27:37.810
genuinely worthwhile watch. The radiance

674
00:27:37.810 --> 00:27:39.970
sits low in your southern sky rather than

675
00:27:39.970 --> 00:27:42.730
overhead, so you'll see fewer of them. But

676
00:27:42.730 --> 00:27:45.210
the ones you do catch travel long paths

677
00:27:45.210 --> 00:27:47.650
across the sky, and they can be spectacular.

678
00:27:47.970 --> 00:27:50.450
Best time is after midnight through to dawn.

679
00:27:50.770 --> 00:27:52.930
Southern Europe, the Mediterranean, North

680
00:27:52.930 --> 00:27:54.210
Africa. Same deal.

681
00:27:54.770 --> 00:27:55.890
Anna: And where do people look?

682
00:27:56.370 --> 00:27:58.850
Avery: The radiant is in Aquarius, near the star

683
00:27:58.850 --> 00:28:01.770
Delta Aquarii. Use Fomalhaut to find

684
00:28:01.770 --> 00:28:04.690
the region. But honestly, don't stare at

685
00:28:04.690 --> 00:28:07.690
the radiant. Lie back, take in as much sky as

686
00:28:07.690 --> 00:28:10.649
you can and let them come to you. Parent body

687
00:28:10.649 --> 00:28:12.330
is suspected to be Comet

688
00:28:12.330 --> 00:28:15.330
96PMachholz. There are also

689
00:28:15.330 --> 00:28:18.050
the Alpha Capricornids building to the 30th

690
00:28:18.050 --> 00:28:20.930
and 31st. Far fewer meteors, but

691
00:28:20.930 --> 00:28:23.710
few famous for slow, brilliant fireballs that

692
00:28:23.710 --> 00:28:25.590
can punch straight through moonlight.

693
00:28:25.910 --> 00:28:27.670
Anna: And for the north, there's something

694
00:28:27.750 --> 00:28:29.190
considerably bigger coming.

695
00:28:29.830 --> 00:28:32.190
Avery: There is, and if you're listening in North

696
00:28:32.190 --> 00:28:34.510
America or Europe, you should be planning for

697
00:28:34.510 --> 00:28:37.269
this. Now, two things land together on the

698
00:28:37.269 --> 00:28:40.190
12th of August 1st, the Perseids Peak.

699
00:28:40.190 --> 00:28:42.830
And this year the moon is new that same day,

700
00:28:42.830 --> 00:28:45.670
which means A properly dark sky that

701
00:28:45.670 --> 00:28:48.650
is the best Perseid year in some time. And

702
00:28:48.650 --> 00:28:51.130
the second, a, uh, total solar

703
00:28:51.130 --> 00:28:53.850
eclipse, the first on mainland Europe

704
00:28:53.930 --> 00:28:56.890
since 1999 and the first in Spain

705
00:28:56.890 --> 00:28:59.890
since 1905. Totality sweeps

706
00:28:59.890 --> 00:29:02.610
across the Arctic, Greenland, Iceland and

707
00:29:02.610 --> 00:29:05.210
northern Spain. And in Spain, it happens

708
00:29:05.210 --> 00:29:07.730
close to sunset, with the sun only a few

709
00:29:07.730 --> 00:29:10.130
degrees above the horizon, which could be

710
00:29:10.130 --> 00:29:11.050
extraordinary.

711
00:29:11.610 --> 00:29:14.250
Anna: North America doesn't get totality this time.

712
00:29:15.090 --> 00:29:18.090
Avery: No, and I won't oversell it, but there is a

713
00:29:18.090 --> 00:29:20.490
real partial eclipse across much of the

714
00:29:20.490 --> 00:29:23.330
continent. Alaska gets the deepest view

715
00:29:23.330 --> 00:29:26.010
near sunrise. Atlantic Canada gets

716
00:29:26.010 --> 00:29:28.450
roughly half the sun covered at maximum in

717
00:29:28.450 --> 00:29:30.649
the afternoon. New England and the

718
00:29:30.649 --> 00:29:32.970
northeastern states get a smaller bite. And

719
00:29:32.970 --> 00:29:35.010
there's some coverage visible right across

720
00:29:35.090 --> 00:29:37.570
every Canadian province and the northern

721
00:29:37.570 --> 00:29:39.530
contiguous states, though.

722
00:29:39.530 --> 00:29:40.610
Anna: Dig out the glasses.

723
00:29:41.080 --> 00:29:43.800
Avery: Dig out the eclipse glasses from 2024 and

724
00:29:43.800 --> 00:29:45.180
check their ISO 1, uh,

725
00:29:45.440 --> 00:29:48.200
23122 certified.

726
00:29:48.680 --> 00:29:51.240
It will not get dark even with 50%

727
00:29:51.240 --> 00:29:53.880
coverage. The remaining sun is blindingly

728
00:29:53.880 --> 00:29:56.080
bright, so there is never a safe moment to

729
00:29:56.080 --> 00:29:58.520
look without protection and the lovely

730
00:29:58.520 --> 00:30:00.520
detail. If you're standing in the path of

731
00:30:00.520 --> 00:30:03.120
totality in Spain or Iceland, there's a

732
00:30:03.120 --> 00:30:05.800
genuine chance of a Perseid streaking pass

733
00:30:05.800 --> 00:30:07.000
during those two minutes.

734
00:30:07.660 --> 00:30:10.500
Anna: And tonight for everyone, the Milky

735
00:30:10.500 --> 00:30:10.860
Way

736
00:30:11.100 --> 00:30:13.180
Avery: from the Southern Hemisphere, the galactic

737
00:30:13.180 --> 00:30:16.100
core is riding high overhead right now. One

738
00:30:16.100 --> 00:30:18.340
of the real privileges of our winter, and

739
00:30:18.340 --> 00:30:20.500
it's at its best. From the Northern

740
00:30:20.500 --> 00:30:22.820
Hemisphere, it's lower in the south towards

741
00:30:22.820 --> 00:30:25.580
Sagittarius. But on a dark night, it's still

742
00:30:25.580 --> 00:30:28.540
magnificent. And before dawn, Saturn and

743
00:30:28.540 --> 00:30:30.540
Mars are in the eastern sky for both

744
00:30:30.540 --> 00:30:31.260
hemispheres.

745
00:30:31.740 --> 00:30:33.260
Anna: One more thing before we go.

746
00:30:33.720 --> 00:30:36.680
Avery: The launchers SpaceX is targeting Thursday

747
00:30:36.840 --> 00:30:39.400
the 23rd for Starship Flight 13.

748
00:30:39.960 --> 00:30:42.720
Window opening at 6:45 in the evening

749
00:30:42.720 --> 00:30:45.400
Eastern Time. That's 5:45 Central,

750
00:30:45.640 --> 00:30:48.440
3:45 Pacific and Friday morning,

751
00:30:48.600 --> 00:30:51.440
quarter to nine for us in Australia. 20

752
00:30:51.440 --> 00:30:54.240
Starlink V3 satellites aboard. Second

753
00:30:54.240 --> 00:30:57.080
flight of the V3 vehicle dead and alarm.

754
00:30:57.320 --> 00:30:59.920
And as always with starship, check before you

755
00:30:59.920 --> 00:31:02.440
commit the date has already moved twice.

756
00:31:03.000 --> 00:31:06.000
Anna: That's Astronomy daily for Wednesday 22

757
00:31:06.000 --> 00:31:08.160
July, a mechanic on its way to

758
00:31:08.160 --> 00:31:10.960
geostationary orbit, a rocket stage

759
00:31:10.960 --> 00:31:13.960
two, two weeks from making a new crater, and

760
00:31:13.960 --> 00:31:16.680
23 astronomers asking the world to watch

761
00:31:17.240 --> 00:31:17.600
two

762
00:31:17.600 --> 00:31:20.000
Avery: stars that died in sequence and left their

763
00:31:20.000 --> 00:31:22.920
remnants side by side. The first magnetic

764
00:31:22.920 --> 00:31:25.480
map of a galaxy cluster and an asteroid

765
00:31:25.480 --> 00:31:27.640
breakup that may have been raining down on us

766
00:31:27.640 --> 00:31:28.840
while the Earth froze.

767
00:31:29.540 --> 00:31:31.620
Anna: Donotes sources and links are all at

768
00:31:31.620 --> 00:31:34.500
astronomydaily IO and you can find us

769
00:31:34.500 --> 00:31:37.140
at astrodaily Pod across the socials.

770
00:31:37.460 --> 00:31:39.460
Avery: If you enjoy the show, a, uh, rating or

771
00:31:39.460 --> 00:31:41.860
review genuinely helps other people find us.

772
00:31:42.100 --> 00:31:44.580
Astronomy Daily is part of the bytes.com

773
00:31:44.580 --> 00:31:45.540
podcast network.

774
00:31:45.860 --> 00:31:46.740
Anna: I'm Anna.

775
00:31:46.900 --> 00:31:49.340
Avery: And I'm, um, Avery. Get outside this week. It

776
00:31:49.340 --> 00:31:50.340
won't be dark for long.

777
00:31:50.740 --> 00:31:51.620
Anna: Clear skies.