Half the Neutron Stars

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Anna: Hello and welcome to Astronomy AstroDailyPod.

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It's Friday the 11th of, uh, September

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2026. This is series

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five, episode 191.

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And I'm Anna.

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Avery: And I'm Avery.

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Anna. Today's lead is a paper arguing that

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one of the rarest, strangest objects in the

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galaxy isn't rare at all.

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Anna: Magnetars. Neutron stars with

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magnetic fields so strong the number stops

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meaning anything. And we know of about 30 of

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them against a few thousand ordinary radio

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pulsars. So the picture has always been

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exotic, freakish. One in a hundred.

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A new paper in Nature Astronomy says that

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picture is a counting error and the real

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figure is closer to one in two.

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Avery: Half. Half of all neutron stars.

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Anna: Half. And if that's right, it doesn't just

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reshuffle a catalogue. It changes how many

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supernovae, uh, our galaxy has to be

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producing. And it quietly props up. The

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leading explanation for some of the most

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extreme events in the universe, including

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the fast radio bursts we spent yesterday's

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lead on.

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Avery: After that, the rings around a small

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icy body 2 billion kilometres away

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have changed. One thickened, one

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thinned in the space of five years. And the

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James Webb Space Telescope caught it by

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watching the thing pass in front of a star.

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Anna: A spacecraft skimming 165 kilometres

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above Mercury at the exact moment the sun

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let go of a burst of particles and measuring

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them landing on the surface.

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Avery: Europe writing a 760 million

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euro cheque for something it has never once

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been able to do. Bring cargo home

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from orbit.

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Anna: And a quick one on Parker solar probe

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checking in from its 29th trip through the

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sun's atmosphere.

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Avery: Plus the sky for both hemispheres. New

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Moon was this afternoon, so tonight is as

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dark as September gets. And there's a

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genuinely lovely pairing this weekend that

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the south gets the better view of. Let's get

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into it.

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Anna: Ready when you are.

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Avery: Start me at the beginning. What's a magnetar?

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Anna: Start one step further back. A neutron star.

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Take a star 8 to 20 something times the mass

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of the sun, magnifying, run it out of fuel

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and the core collapses in about a second.

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What's left is a ball roughly 20 kilometres

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across with more mass than the sun packed

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into it. A teaspoon of the material weighs

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about as much as a mountain range.

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Avery: And they come in flavours, that's the part

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that matters.

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Anna: Today we've catalogued them as separate

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species, largely because of how we found

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them. There are radio pulsars, the

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lighthouse ones, thousands of them, spinning

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fast and beaming. There are central compact

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objects sitting quietly inside supernova

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remnants Doing almost nothing. There are X

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ray dim isolated neutron stars, which

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are exactly as boring as they sound. And then

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there are magnetars, which are not

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boring. The opposite. A

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magnetar's magnetic field is somewhere around

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10 to the 14, 10 to the 15

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gauss. Earth's is about half a gauss.

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A hospital MRI about 15,000,

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so something like a quadrillion times Earth.

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And structurally, the key point is that a

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magnetar isn't powered by its spin the way a

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pulsar is. It's powered by that field

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decaying. The field is the fuel tank.

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Avery: What does that look like from the outside?

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Anna: Violence in short bursts. The

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crust is a rigid solid under enormous

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magnetic stress. And every so often it

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cracks a starquake and the object

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releases more energy in a fraction of a

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second than the sun manages in a hundred

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thousand years. In 2004,

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one of them put out a flare that measurably

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ionised Earth's upper atmosphere from 50,000

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light years away.

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Avery: And we know of about 30.

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Anna: About 30 confirmed against several thousand

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radio pulsars. Which is where the counting

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error creeps in, because those two numbers

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are not measuring the same thing.

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Avery: Explain that.

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Anna: A radio pulsar is a long lived, steady

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beacon. It'll beam for tens of millions of

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years, and we've spent 60 years building

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surveys designed to catch exactly that. A

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magnetar is the opposite. Bright and obvious

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for a few thousand years, powered by a field

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that is actively destroying itself. And then

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it fades into something much harder to

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identify. So if you count what's in the

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catalogues, you're counting how long each

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type stays visible to the instruments we

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happen to have built, not how many get born.

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Avery: So how do you count births instead of

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sightings?

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Anna: You build the galaxy in a computer. That's

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this work. Celsa Pardo Araujo and

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Nanda Rea at the Institute of Space Sciences

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in Barcelona with Michelle Ronke at

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ASTRON in the Netherlands and Vanessa Graeber

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at Royal Holloway in London. Published this

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week in Nature Astronomy. It's a population

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synthesis. Assume a distribution of

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magnetic fields and spins at birth, then

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evolve the whole simulated population

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forward.

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Avery: Evolve how?

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Anna: Three things at once, which is the technical

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advance. The spindown, how the rotation

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bleeds away, the magnetothermal evolution,

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how the field decays and how the crust

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coolswhich are coupled to each other and. And

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the galactic dynamics. These things get

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kicked at birth by the supernova and drift

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away from where they were born, which changes

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how far off and how obscured they look. Then

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you run the simulated population through the

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same detection filters as the real surveys

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and ask which starting assumption produces

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the sky we actually see.

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Avery: And the anchor is what? The full catalogue.

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Anna: The tightest anchor is the young end, and

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it's a small number. There are 24

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known isolated neutron stars in our galaxy

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younger than 2000 years. That's the sample

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where nothing has had time to fade. So it's

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the fairest census we've got. And in that

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sample, magnetars and central compact

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objects together make up about

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59%,

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Avery: nearly 6 in 10 of the young ones.

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Anna: They combine that with a volume limited

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sample of the x ray dim objects,

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and what comes out is a birth fraction for

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magnetars averaging around 50% of

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the entire neutron star population.

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The range depends on what you assume about

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the field distribution at birth.

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If it peaks around one times 10 to the 14

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gauss, you get 40 to 70%.

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If it peaks a bit higher, around two and a

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half times 10 to the 14, you get 30 to 50.

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Avery: So the headline number is about half with

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honest width on it.

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Anna: About half with width. And Pardo

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Araujo's own framing of why it took this long

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is worth quoting.

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She says it's essential to model the

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different types of isolated neutron star in a

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unified way, together with their possible

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evolutionary connections, because that's what

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lets you estimate consistently how many

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magnetars form. In other words, the

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mistake was treating four catalogues as four

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species instead of one population seen

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at different stages.

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Avery: Right. So what breaks if this is true?

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Anna: Two things.

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And the first is a lovely piece of

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arithmetic. If half of all neutron stars are

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magnetars, and magnetars are only visible

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for a couple of thousand years, then to keep

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the observed population topped up, the

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galaxy has to be making neutron stars faster

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than we'd assumed. They derive a core

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collapse supernova rate of about 2 per

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century. 2.01 with a

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generous error bar running from about 1 to

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nearly 4. And the old number,

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the conventional figure, has sat at roughly

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one to two per century for a long time.

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And estimates have often drifted towards the

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low end. So this pushes the galaxy's

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supernova rate up from a completely

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independent direction. That's the part I

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like. It's not a supernova paper and it still

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lands on the supernova rate. And the second

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thing, the second is bigger, and it's about

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the rest of the universe. There's a family of

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extreme events nobody can fully explain.

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Super luminous supernovae, ten to a

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hundred times brighter than a normal one. The

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long plateaus in gamma ray burst afterglows

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where something keeps injecting energy after

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the explosion should be over and fast.

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Avery: Radio bursts, which was yesterday's lead

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from

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Anna: the other end, a hundred and nine of them

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used to weigh the ordinary matter of the

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universe. And for all three, the

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leading explanation is the a

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newborn magnetar in the middle, dumping its

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magnetic energy into the debris. We know it's

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physically possible because in 2020, a

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magnetar in our own galaxy, SGR

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1935, 2154,

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produced a fast radio burst and settled that

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question.

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Avery: So what was missing was the supply.

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Anna: Exactly. The supply.

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A central engine model needs there to be

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enough engines. If magnetars were a 1%

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curiosity, then explaining a whole class of

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common extragalactic transients with them is

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a stretch. If they're half of all neutron

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stars, the budget works. The paper is

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explicit that this lends strong support to

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the models. It doesn't prove them, it makes

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them affordable.

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Avery: Caveats. Give me the honest ones.

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Anna: 3. First, this is a model, not a

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census. Nobody counted 50 million

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magnetars. It's a simulation tuned to

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reproduce what we see. And if the assumed

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shape of the birth field distribution is

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wrong, the answer moves. The paper

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is up front that the 50% depends on assuming

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a 2 peaked field distribution at birth.

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Second, the anchor sample is 24

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objects. 24.

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That's the tightest constraint they have. And

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it's also a very small number to hang a

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galaxy on. And third,

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magnetar here is defined by a threshold,

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a dipole field above about 10 to the

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13.5 gauss. And nature doesn't

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come with a threshold. Some objects sit right

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on the line.

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Avery: And where does the work go next?

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Anna: Ria's answer is the obvious one and also the

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right one tested outside our galaxy.

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A, uh, natural extension, she says, would be

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to cheque these results in an extragalactic

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context, which is exactly where the

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transients are.

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Avery: And there's a southern thread here, isn't

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there?

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Anna: There's a good one, and it's not decorative,

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it's foundational.

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The entire field of magnetars starts in the

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southern sky. On 5 March

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1979, a burst of gamma rays swept through

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the solar system so hard that it saturated

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instruments on nine separate spacecraft. And

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when it was traced back, it came from the

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N49 supernova remnant in the Large

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Magellanic Cloud, SGR

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0526 66,

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00:11:02.390 --> 00:11:04.910
a southern sky object in a southern sky

267
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satellite galaxy. That event is the reason

268
00:11:07.550 --> 00:11:09.590
the word magnetar exists at all.

269
00:11:10.070 --> 00:11:11.270
Avery: And the modern end?

270
00:11:11.590 --> 00:11:13.510
Anna: The modern end runs through Western

271
00:11:13.510 --> 00:11:16.460
Australia. In 2022, a survey with

272
00:11:16.460 --> 00:11:19.220
the Murchison Widefield Array at Inyarimanha

273
00:11:19.220 --> 00:11:21.940
Il Ghari Bundara, the same site that'll host

274
00:11:21.940 --> 00:11:24.260
Ska Lo turned up Gleam

275
00:11:24.260 --> 00:11:26.980
XJ16000 2759,

276
00:11:27.380 --> 00:11:29.580
an object switching on for a minute at a time

277
00:11:29.580 --> 00:11:32.460
every 18 minutes. Far too slow for anything

278
00:11:32.460 --> 00:11:34.340
we thought could produce radio emission like

279
00:11:34.340 --> 00:11:36.380
that. And the follow up that took that

280
00:11:36.380 --> 00:11:39.140
Australian discovery seriously as a possible

281
00:11:39.220 --> 00:11:42.210
ultra long period magnetar was led out of

282
00:11:42.210 --> 00:11:44.650
the same Barcelona group using the same

283
00:11:44.650 --> 00:11:46.730
magnetothermal machinery behind today's

284
00:11:46.730 --> 00:11:49.170
result, same tools, same people.

285
00:11:49.730 --> 00:11:52.450
Southern data, which is how this actually

286
00:11:52.530 --> 00:11:53.090
works.

287
00:11:53.650 --> 00:11:56.370
A wide field radio survey on Guadari

288
00:11:56.370 --> 00:11:59.010
country finds something nobody can classify.

289
00:11:59.730 --> 00:12:02.330
A theory group in Spain builds the model that

290
00:12:02.330 --> 00:12:05.010
might explain it. And four years later

291
00:12:05.250 --> 00:12:07.930
the model tells us we've been miscounting the

292
00:12:07.930 --> 00:12:08.770
whole population.

293
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Avery: Storey2 and it's small, distant and

294
00:12:12.820 --> 00:12:15.820
genuinely strange. Chariklo is

295
00:12:15.820 --> 00:12:18.460
a centaur, one of the icy bodies on

296
00:12:18.460 --> 00:12:20.780
unstable orbits between Jupiter and

297
00:12:20.780 --> 00:12:21.540
Neptune.

298
00:12:21.540 --> 00:12:24.460
In Chariklo's case, crossing between Saturn

299
00:12:24.460 --> 00:12:26.620
and uranus. It's about

300
00:12:26.620 --> 00:12:29.420
250 kilometres across, so a

301
00:12:29.420 --> 00:12:32.380
radius of roughly 125, which

302
00:12:32.380 --> 00:12:34.820
makes it the largest centaur we know of.

303
00:12:35.460 --> 00:12:38.300
And in 2013, it became the first object

304
00:12:38.300 --> 00:12:40.700
smaller than a planet ever found to have

305
00:12:40.700 --> 00:12:41.140
rings.

306
00:12:41.700 --> 00:12:44.500
Anna: Found how? You can't image something that

307
00:12:44.500 --> 00:12:45.780
small at that distance.

308
00:12:46.420 --> 00:12:49.260
Avery: You can't. You watch it pass in front of a

309
00:12:49.260 --> 00:12:51.820
star and time the shadow A, uh, stellar

310
00:12:51.820 --> 00:12:54.660
occultation. The star blinks out.

311
00:12:54.820 --> 00:12:57.620
You measure for exactly how long and from

312
00:12:57.620 --> 00:12:59.700
telescopes at different sites, you

313
00:12:59.700 --> 00:13:01.900
reconstruct the shape of whatever passed in

314
00:13:01.900 --> 00:13:04.670
front of. In 2013, a campaign

315
00:13:04.910 --> 00:13:07.870
strung across Chile, Brazil, Argentina

316
00:13:07.870 --> 00:13:10.750
and Uruguay caught Chariklo doing that.

317
00:13:10.750 --> 00:13:12.910
And the star didn't blink once.

318
00:13:13.470 --> 00:13:16.350
It blinked twice on the way in and twice on

319
00:13:16.350 --> 00:13:19.230
the way out. Rings, two

320
00:13:19.230 --> 00:13:21.910
of them sharp, narrow and a

321
00:13:21.910 --> 00:13:24.710
complete surprise. At the time, rings

322
00:13:24.710 --> 00:13:27.430
were something planets had. They sit about

323
00:13:27.430 --> 00:13:30.070
390 and 405

324
00:13:30.070 --> 00:13:32.270
kilometres from the centre, one a few

325
00:13:32.270 --> 00:13:33.630
kilometres wide each.

326
00:13:33.870 --> 00:13:36.190
And they've been called Chariklos pocket

327
00:13:36.190 --> 00:13:37.310
rings ever since.

328
00:13:37.870 --> 00:13:39.390
Anna: And Webb has now looked.

329
00:13:39.790 --> 00:13:42.190
Avery: Webb looked on 18 October

330
00:13:42.350 --> 00:13:45.150
2022, the first stellar occultation

331
00:13:45.230 --> 00:13:47.710
ever specifically planned for the telescope.

332
00:13:48.190 --> 00:13:51.030
The payoff is wavelength. Webb sees

333
00:13:51.030 --> 00:13:53.870
out to five microns in the infrared, which

334
00:13:53.870 --> 00:13:55.390
isn't available from the ground.

335
00:13:55.630 --> 00:13:57.670
And it resolved the rings to about a

336
00:13:57.670 --> 00:14:00.550
kilometre. Published this week in Science

337
00:14:00.550 --> 00:14:03.310
Advances, led by Yucel Kilitz,

338
00:14:03.310 --> 00:14:06.270
Pablo Santos Sanz and Celia Navis at

339
00:14:06.270 --> 00:14:08.790
the Institute of Astrophysics of Andalusia

340
00:14:08.870 --> 00:14:11.830
with Nicolas Rambo, Bruno Siccardi and

341
00:14:11.830 --> 00:14:13.830
Jocelyn Demars in Paris.

342
00:14:14.310 --> 00:14:15.350
Anna: And what changed?

343
00:14:15.830 --> 00:14:18.150
Avery: Both rings in opposite directions.

344
00:14:18.790 --> 00:14:20.910
Compared with the ground based occultations

345
00:14:20.910 --> 00:14:23.430
of 2017, the inner ring

346
00:14:25.170 --> 00:14:27.730
is now about 50% more opaque.

347
00:14:28.290 --> 00:14:31.290
The outer ring, C2R, has gone

348
00:14:31.290 --> 00:14:34.210
the other way. Its opacity has dropped by

349
00:14:34.210 --> 00:14:36.970
around 60% and the positions

350
00:14:36.970 --> 00:14:39.770
haven't moved at all. The rings are where

351
00:14:39.770 --> 00:14:42.730
they were. It's the material in them that's

352
00:14:42.730 --> 00:14:43.010
different.

353
00:14:43.490 --> 00:14:44.450
Anna: In five years.

354
00:14:45.170 --> 00:14:47.970
Avery: In five years around an object that takes

355
00:14:47.970 --> 00:14:50.050
63 years to go round the sun.

356
00:14:50.940 --> 00:14:53.460
That's the finding. These are not static

357
00:14:53.460 --> 00:14:56.020
structures you can photograph once and file

358
00:14:56.020 --> 00:14:58.820
away. They're dynamically active on a

359
00:14:58.820 --> 00:15:01.100
timescale a human being can sit through.

360
00:15:01.500 --> 00:15:02.460
Anna: What would do that?

361
00:15:02.540 --> 00:15:05.340
Avery: Nobody knows yet, and the paper says so.

362
00:15:05.580 --> 00:15:07.540
The outer ring thinning could be

363
00:15:07.540 --> 00:15:10.500
straightforward material loss. The inner

364
00:15:10.500 --> 00:15:13.220
one thickening could be material arriving or

365
00:15:13.220 --> 00:15:15.820
collisions grinding larger particles into

366
00:15:15.820 --> 00:15:18.510
finer grains, which are more opaque per

367
00:15:18.510 --> 00:15:21.150
kilogramme. And the team adds a third

368
00:15:21.150 --> 00:15:23.830
possibility that isn't astrophysics at all.

369
00:15:24.230 --> 00:15:26.590
They're comparing infrared measurements with

370
00:15:26.590 --> 00:15:28.310
older visible light ones.

371
00:15:28.630 --> 00:15:30.710
So some of the difference could be about what

372
00:15:30.710 --> 00:15:33.470
each wavelength is sensitive to, rather than

373
00:15:33.470 --> 00:15:35.110
the rings actually changing.

374
00:15:35.990 --> 00:15:38.990
Anna: So the result is a real change, a

375
00:15:38.990 --> 00:15:41.790
suspected cause and an unresolved

376
00:15:41.790 --> 00:15:42.470
confound.

377
00:15:43.200 --> 00:15:45.640
Avery: That's a fair summary. And it's why the next

378
00:15:45.640 --> 00:15:48.000
occultation matters more than this one.

379
00:15:48.480 --> 00:15:49.760
The southern hemisphere.

380
00:15:49.760 --> 00:15:52.120
Point here is that this whole technique is

381
00:15:52.120 --> 00:15:54.640
ours by geography and by habit.

382
00:15:54.960 --> 00:15:57.400
Chariklos rings were discovered from South

383
00:15:57.400 --> 00:16:00.280
American soil. Occultation chasing is

384
00:16:00.280 --> 00:16:02.440
a discipline where a well placed amateur

385
00:16:02.440 --> 00:16:05.280
telescope in rural Australia or New Zealand

386
00:16:05.520 --> 00:16:08.320
can contribute real data. And the shadow

387
00:16:08.320 --> 00:16:11.150
tracks fall where they fall, which is often

388
00:16:11.230 --> 00:16:13.230
down here, storey three.

389
00:16:13.470 --> 00:16:15.430
Anna: And it's a piece of luck that turned into a

390
00:16:15.430 --> 00:16:15.710
result.

391
00:16:16.270 --> 00:16:18.990
BepiColombo, the joint European and

392
00:16:18.990 --> 00:16:21.430
Japanese mission to Mercury, which we've been

393
00:16:21.430 --> 00:16:24.030
following as it comes in to arrive, made its

394
00:16:24.030 --> 00:16:26.990
fourth flyby of the planet in September 2024

395
00:16:27.310 --> 00:16:30.030
and it came in low, 165

396
00:16:30.030 --> 00:16:32.870
kilometres above the surface, which is closer

397
00:16:32.870 --> 00:16:34.590
Avery: than it'll be when it's actually in

398
00:16:34.590 --> 00:16:36.990
Anna: orbit, closer than the science orbit, which

399
00:16:36.990 --> 00:16:39.860
is the point the team keeps making. And at

400
00:16:39.860 --> 00:16:42.660
the exact moment it was down there, the sun

401
00:16:42.660 --> 00:16:45.260
let go of a major eruption of energetic

402
00:16:45.260 --> 00:16:48.220
particles. The lead author, Kilpua

403
00:16:48.380 --> 00:16:50.460
at the University of Helsinki, puts it

404
00:16:50.460 --> 00:16:50.940
plainly.

405
00:16:51.260 --> 00:16:54.140
The fourth flyby was unique. The spacecraft

406
00:16:54.140 --> 00:16:56.100
was much closer to the surface than it will

407
00:16:56.100 --> 00:16:58.700
ever be in its final orbit. And they were

408
00:16:58.700 --> 00:17:01.300
lucky that a major particle eruption happened

409
00:17:01.300 --> 00:17:03.420
on the sun at precisely that moment.

410
00:17:03.980 --> 00:17:05.100
Avery: So what did it see?

411
00:17:05.640 --> 00:17:06.080
Anna: It watched.

412
00:17:06.080 --> 00:17:08.120
The particles get through. High energy

413
00:17:08.120 --> 00:17:10.600
electrons and protons penetrated Mercury's

414
00:17:10.600 --> 00:17:13.000
magnetic field and precipitated onto the

415
00:17:13.000 --> 00:17:15.760
surface across a wide area. The instrument is

416
00:17:15.760 --> 00:17:18.600
called sixis, the Solar Intensity X

417
00:17:18.600 --> 00:17:21.200
Ray and Particle Spectrometer, designed and

418
00:17:21.200 --> 00:17:23.760
built in Finland, and the work has just been

419
00:17:23.760 --> 00:17:25.560
published in Nature Astronomy.

420
00:17:25.880 --> 00:17:28.040
Avery: Why does it matter where particles land?

421
00:17:28.440 --> 00:17:29.280
Anna: Two reasons.

422
00:17:29.280 --> 00:17:31.810
And the first is practical. When energetic

423
00:17:31.810 --> 00:17:34.290
particles hit an airless surface, they knock

424
00:17:34.290 --> 00:17:36.810
atoms and molecules off it and they make the

425
00:17:36.810 --> 00:17:39.130
surface fluoresce in X rays. That

426
00:17:39.130 --> 00:17:41.130
fluorescence is exactly how you read the

427
00:17:41.130 --> 00:17:42.970
chemical composition of a planet you can't

428
00:17:42.970 --> 00:17:45.530
land on. So if you want to map what Mercury

429
00:17:45.530 --> 00:17:47.250
is made of, you need to know what's

430
00:17:47.250 --> 00:17:49.930
bombarding it and where. This is calibration

431
00:17:49.930 --> 00:17:51.490
for the mission's own science.

432
00:17:52.050 --> 00:17:52.770
Avery: And the second?

433
00:17:52.930 --> 00:17:55.850
Anna: The second is that it's weathering over

434
00:17:55.850 --> 00:17:58.750
geological time. That bombardment is one

435
00:17:58.750 --> 00:18:01.630
of the things reworking the surface, along

436
00:18:01.630 --> 00:18:04.430
with the solar wind and micrometeorites.

437
00:18:04.910 --> 00:18:07.310
And there's a third payoff that reaches back

438
00:18:07.310 --> 00:18:10.270
here. Rami Vainio at the University

439
00:18:10.270 --> 00:18:13.150
of Turku, the CO investigator, makes

440
00:18:13.150 --> 00:18:15.710
the point that Mercury has a real magnetic

441
00:18:15.710 --> 00:18:18.270
field, but a small, weak

442
00:18:18.350 --> 00:18:21.350
magnetosphere, which makes it a natural

443
00:18:21.350 --> 00:18:23.790
stand in for what Earth looks like during an

444
00:18:23.790 --> 00:18:25.650
extreme solar solar storm.

445
00:18:26.370 --> 00:18:29.370
Mercury is the experiment we can't run on

446
00:18:29.370 --> 00:18:29.890
ourselves.

447
00:18:30.770 --> 00:18:32.930
Avery: And where is the spacecraft now?

448
00:18:33.330 --> 00:18:35.650
Anna: In the middle of the most interesting stretch

449
00:18:35.650 --> 00:18:38.570
of its life, it separated its transfer

450
00:18:38.570 --> 00:18:41.530
module, the big electric propulsion stack

451
00:18:41.530 --> 00:18:43.490
that's been doing the work for eight years.

452
00:18:44.050 --> 00:18:46.450
On the 3rd of September, eight days ago,

453
00:18:46.930 --> 00:18:49.690
gravity capture at Mercury is on the 21st of

454
00:18:49.690 --> 00:18:52.080
November. The Japanese orbiter

455
00:18:52.880 --> 00:18:54.760
gets released around the 9th or 10th of

456
00:18:54.760 --> 00:18:55.200
December.

457
00:18:55.520 --> 00:18:58.040
And the European orbiter reaches its final

458
00:18:58.040 --> 00:19:00.880
science orbit in March, with routine science

459
00:19:00.880 --> 00:19:03.760
from April. So this flyby result is arriving

460
00:19:03.760 --> 00:19:06.200
as a kind of advanced sample of what the

461
00:19:06.200 --> 00:19:08.240
mission is about to start doing properly.

462
00:19:10.080 --> 00:19:13.000
Avery: And it's money rather than physics, but it's

463
00:19:13.000 --> 00:19:15.120
the kind of money that changes what's

464
00:19:15.120 --> 00:19:17.970
possible. Yesterday, the European Space

465
00:19:17.970 --> 00:19:20.650
Agency awarded a contract worth up to

466
00:19:20.650 --> 00:19:23.410
760 million euros to a

467
00:19:23.410 --> 00:19:26.330
German startup called the Exploration Company

468
00:19:26.810 --> 00:19:29.810
to build a spacecraft that can carry cargo to

469
00:19:29.810 --> 00:19:32.329
the International Space Station. And

470
00:19:32.570 --> 00:19:34.970
this is the part Europe has never done.

471
00:19:35.290 --> 00:19:36.170
Bring it back.

472
00:19:36.810 --> 00:19:39.650
Anna: Never. Europe flew cargo to the station for

473
00:19:39.650 --> 00:19:39.930
years.

474
00:19:40.730 --> 00:19:43.290
Avery: Flew it up, yes. The ATVs,

475
00:19:43.450 --> 00:19:45.900
five of them, big and successful.

476
00:19:46.460 --> 00:19:48.540
Every one of them was then deliberately

477
00:19:48.540 --> 00:19:51.420
destroyed on the way down. Europe has

478
00:19:51.420 --> 00:19:53.860
never returned anything from orbit to the

479
00:19:53.860 --> 00:19:56.860
ground. That capability belongs to the United

480
00:19:56.940 --> 00:19:59.780
States, Russia and China. And

481
00:19:59.780 --> 00:20:01.860
it's the difference between shipping and

482
00:20:01.860 --> 00:20:04.820
shipping, both ways. Experiments, you

483
00:20:04.820 --> 00:20:07.500
can actually get back, Hardware you can

484
00:20:07.500 --> 00:20:09.980
inspect, samples that survive.

485
00:20:10.680 --> 00:20:11.800
Anna: What's the shape of the deal?

486
00:20:12.280 --> 00:20:14.960
Avery: It runs under a programme ESA calls

487
00:20:14.960 --> 00:20:17.160
Aladdin. And the structure is

488
00:20:17.160 --> 00:20:19.880
310 million euros for the

489
00:20:19.880 --> 00:20:22.840
demonstration mission, with ESA covering

490
00:20:22.840 --> 00:20:25.840
60% of that and the company funding the

491
00:20:25.840 --> 00:20:27.720
other 40, plus

492
00:20:27.720 --> 00:20:30.680
450 million in options for

493
00:20:30.680 --> 00:20:33.680
two further missions. The vehicle is called

494
00:20:33.680 --> 00:20:36.600
Nix. It flies on Ariane 6

495
00:20:36.990 --> 00:20:39.630
and it has to dock with the space station no

496
00:20:39.630 --> 00:20:42.430
later than the second quarter of 2029.

497
00:20:42.990 --> 00:20:45.870
There's also up to 50 million euros in

498
00:20:45.870 --> 00:20:48.430
additional incentive for flying on European

499
00:20:48.430 --> 00:20:51.230
launch vehicles, which tells you what else

500
00:20:51.230 --> 00:20:52.830
this contract is really for.

501
00:20:53.390 --> 00:20:54.990
Anna: And the company is how old?

502
00:20:55.150 --> 00:20:58.110
Avery: Founded in 2021. Their chief executive,

503
00:20:58.430 --> 00:21:01.070
Ellen Huby, is quite direct about how

504
00:21:01.070 --> 00:21:03.990
unusual that is. She says it's the first

505
00:21:03.990 --> 00:21:06.230
time in Europe that a five year old space

506
00:21:06.230 --> 00:21:08.830
startup has won a contract worth hundreds of

507
00:21:08.830 --> 00:21:10.070
millions of euros.

508
00:21:10.550 --> 00:21:13.350
ESA's Daniel Neuenschwander frames it

509
00:21:13.350 --> 00:21:15.870
as getting Europe one step closer to a

510
00:21:15.870 --> 00:21:18.430
capability only a handful of nations have

511
00:21:18.430 --> 00:21:21.310
mastered. And it's worth noting ESA

512
00:21:21.310 --> 00:21:23.430
hasn't closed the door on the alternative.

513
00:21:23.750 --> 00:21:26.470
Thales Alenius Space in Italy is

514
00:21:26.470 --> 00:21:28.150
still in a parallel tender.

515
00:21:28.750 --> 00:21:30.190
Anna: Has the company flown anything?

516
00:21:30.670 --> 00:21:31.390
Avery: It has.

517
00:21:31.390 --> 00:21:34.350
And this is the honest caveat. In

518
00:21:34.350 --> 00:21:36.790
June 2025, they flew a small

519
00:21:36.790 --> 00:21:39.750
reentry capsule called Mission Possible. As a

520
00:21:39.750 --> 00:21:42.670
rideshare, it launched, it operated in

521
00:21:42.670 --> 00:21:45.550
orbit, it survived reentry and then

522
00:21:45.550 --> 00:21:48.270
contact was lost shortly before splashdown

523
00:21:48.350 --> 00:21:51.030
and the capsule was not recovered. The

524
00:21:51.030 --> 00:21:53.830
company called it a partial success, which is

525
00:21:53.830 --> 00:21:56.710
fair in both directions. So the jump

526
00:21:56.710 --> 00:21:58.870
from that to docking with the space station

527
00:21:58.870 --> 00:22:01.630
and returning intact is a very large one

528
00:22:01.630 --> 00:22:03.070
on a fixed timeline.

529
00:22:03.550 --> 00:22:04.830
Anna: And the strategic read?

530
00:22:05.390 --> 00:22:07.910
Avery: It's the same thread we were pulling on six

531
00:22:07.910 --> 00:22:10.790
days ago. With Isar Aerospace reaching orbit

532
00:22:10.790 --> 00:22:13.590
from Norway within one fortnight,

533
00:22:13.590 --> 00:22:15.830
Europe has launched to orbit from its own

534
00:22:15.830 --> 00:22:18.590
soil for the first time and bought itself a

535
00:22:18.590 --> 00:22:21.590
route home. The target isn't really the space

536
00:22:21.590 --> 00:22:24.310
station either. The ISS has a

537
00:22:24.310 --> 00:22:25.630
handful of years left.

538
00:22:26.230 --> 00:22:28.550
It's whatever commercial stations replace it.

539
00:22:28.710 --> 00:22:30.390
And who gets to service them?

540
00:22:30.870 --> 00:22:33.830
Anna: One quick one before the sky. NASA's Parker

541
00:22:33.830 --> 00:22:36.510
Solar Probe has reported in after its 29th

542
00:22:36.510 --> 00:22:38.990
close approach to the sun, which it made on

543
00:22:38.990 --> 00:22:41.990
4 September. Still holding the record,

544
00:22:42.630 --> 00:22:43.590
still holding it.

545
00:22:43.830 --> 00:22:45.830
And that's now the eighth time it has

546
00:22:46.390 --> 00:22:49.230
430,000 miles an hour, about

547
00:22:49.230 --> 00:22:52.230
690,000 kilometres an hour, and

548
00:22:52.230 --> 00:22:54.870
3.8 million miles from the surface,

549
00:22:55.030 --> 00:22:56.990
which are exactly the numbers it set on

550
00:22:56.990 --> 00:22:59.990
Christmas Eve 2024. It's not going

551
00:22:59.990 --> 00:23:02.710
faster or closer. It's repeating the same

552
00:23:02.710 --> 00:23:05.590
extraordinary pass over and over, which is

553
00:23:05.590 --> 00:23:06.230
the whole design.

554
00:23:06.950 --> 00:23:08.950
Avery: And it goes silent while it does it

555
00:23:09.430 --> 00:23:10.150
completely.

556
00:23:10.390 --> 00:23:12.910
Anna: The encounter ran from the 30th of August to

557
00:23:12.910 --> 00:23:15.510
the 9th of September, and for nine days of

558
00:23:15.510 --> 00:23:18.230
that it's on its own with no contact too

559
00:23:18.230 --> 00:23:19.390
close to the sun to talk.

560
00:23:19.790 --> 00:23:22.070
It sent a beacon tone on the seventh to say

561
00:23:22.070 --> 00:23:24.470
it was healthy. This particular pass was

562
00:23:24.470 --> 00:23:26.830
aimed at the north pole of the sun, looking

563
00:23:26.830 --> 00:23:29.350
at structures and activity up there, and in

564
00:23:29.350 --> 00:23:32.150
one day it sweeps through nearly 40% of the

565
00:23:32.150 --> 00:23:33.150
solar circumference.

566
00:23:33.950 --> 00:23:35.310
Avery: When do we see anything?

567
00:23:35.870 --> 00:23:38.310
Anna: Telemetry started flowing today and the

568
00:23:38.310 --> 00:23:40.710
science data comes down between the 13th and

569
00:23:40.710 --> 00:23:43.510
the 27th. And the mission itself has been

570
00:23:43.510 --> 00:23:46.220
extended through 2029 and after this

571
00:23:46.220 --> 00:23:47.700
year's Heliophysics review.

572
00:23:48.260 --> 00:23:49.780
So there's plenty more of this to

573
00:23:49.780 --> 00:23:52.780
Avery: come and to the sky. And this is a good

574
00:23:52.780 --> 00:23:55.660
weekend for a simple reason. New

575
00:23:55.660 --> 00:23:58.180
Moon fell this afternoon, Sydney time

576
00:23:58.340 --> 00:24:01.300
at 27 minutes past 2. Which

577
00:24:01.300 --> 00:24:03.780
means tonight and tomorrow night are the

578
00:24:03.780 --> 00:24:04.900
darkest of the month.

579
00:24:05.060 --> 00:24:08.060
And the moon comes back as a thin evening

580
00:24:08.060 --> 00:24:10.820
crescent just in time to do something pretty.

581
00:24:11.790 --> 00:24:12.990
Anna: Southern hemisphere first.

582
00:24:13.870 --> 00:24:16.870
Avery: From Sydney and similar latitudes, Venus

583
00:24:16.870 --> 00:24:19.430
is the evening object and it wants dealing

584
00:24:19.430 --> 00:24:22.030
with promptly. Low in the west after

585
00:24:22.030 --> 00:24:24.830
sunset and setting quickly. So the window

586
00:24:24.830 --> 00:24:27.830
is the first 45 minutes once the sky

587
00:24:27.830 --> 00:24:28.430
darkens.

588
00:24:29.070 --> 00:24:31.030
Worth the trouble because it's building

589
00:24:31.030 --> 00:24:33.790
towards greatest Brilliancy on the 18th

590
00:24:33.790 --> 00:24:36.350
at magnitude -4.8,

591
00:24:36.840 --> 00:24:39.240
about as bright as Venus ever gets.

592
00:24:40.120 --> 00:24:42.880
Anna: And the pairing you mentioned, Sunday

593
00:24:42.880 --> 00:24:43.200
and

594
00:24:43.200 --> 00:24:45.640
Avery: Monday evening, the 13th and

595
00:24:45.640 --> 00:24:48.440
14th, a very thin waxing

596
00:24:48.440 --> 00:24:51.400
crescent sweeps past Venus and on the

597
00:24:51.400 --> 00:24:53.800
14th they're about half a degree apart.

598
00:24:54.360 --> 00:24:57.160
That's a moon width. Spica is right

599
00:24:57.160 --> 00:24:57.720
there too.

600
00:24:57.960 --> 00:25:00.840
So there's a third point in the picture and

601
00:25:00.840 --> 00:25:03.680
this one is genuinely ours. Earth

602
00:25:03.680 --> 00:25:05.760
Sky's own note is that the southern

603
00:25:05.760 --> 00:25:08.600
hemisphere gets the better view. Find a

604
00:25:08.600 --> 00:25:11.440
clear low western horizon and look

605
00:25:11.440 --> 00:25:13.840
as soon as the sky starts to colour.

606
00:25:14.560 --> 00:25:15.200
Anna: Saturn.

607
00:25:16.080 --> 00:25:18.640
Avery: Saturn is the reliable one for everybody.

608
00:25:18.800 --> 00:25:21.680
Rising in the east not long after sunset,

609
00:25:21.840 --> 00:25:24.240
well up by mid evening, heading for

610
00:25:24.240 --> 00:25:26.680
opposition on the 4th of October. With the

611
00:25:26.680 --> 00:25:29.600
rings about 7 degrees open and

612
00:25:29.600 --> 00:25:32.280
with no moon in the sky, the core of the

613
00:25:32.280 --> 00:25:35.040
Milky Way is still high after dark down

614
00:25:35.040 --> 00:25:37.720
here. Sagittarius and Scorpius

615
00:25:37.720 --> 00:25:40.320
overhead in the early evening. The best

616
00:25:40.320 --> 00:25:43.160
naked eye view in the sky and ours

617
00:25:43.160 --> 00:25:44.480
for a few more weeks.

618
00:25:45.520 --> 00:25:47.680
Anna: There's one more southern thing, and it's

619
00:25:47.680 --> 00:25:48.160
subtle.

620
00:25:48.960 --> 00:25:51.960
Avery: The zodiacal light sunlight scattered

621
00:25:51.960 --> 00:25:54.160
off dust in the plane of the solar system,

622
00:25:54.730 --> 00:25:57.090
looking like a faint pyramid leaning up from

623
00:25:57.090 --> 00:25:59.570
the horizon. It's an equinox

624
00:25:59.570 --> 00:26:01.970
phenomenon. And right now in the southern

625
00:26:01.970 --> 00:26:04.850
hemisphere it's an evening object. Look

626
00:26:04.850 --> 00:26:07.450
west after true darkness and it's often

627
00:26:07.450 --> 00:26:10.290
called the false dusk. You need a

628
00:26:10.290 --> 00:26:13.130
properly dark sight and no moon, which

629
00:26:13.130 --> 00:26:15.370
is precisely what this week gives you.

630
00:26:15.690 --> 00:26:17.930
It runs through to early November

631
00:26:18.890 --> 00:26:19.210
North

632
00:26:19.210 --> 00:26:22.130
Anna: America your turn and you get the same

633
00:26:22.130 --> 00:26:23.290
thing at the other end of

634
00:26:23.290 --> 00:26:26.000
Avery: the night you do for the

635
00:26:26.000 --> 00:26:28.920
northern hemisphere in September the zodiacal

636
00:26:28.920 --> 00:26:31.640
light is a pre dawn object. Look

637
00:26:31.640 --> 00:26:34.280
east in the couple of hours before sunrise

638
00:26:34.280 --> 00:26:36.800
and it's called the false dawn for the

639
00:26:36.800 --> 00:26:39.560
obvious reason. Around the 15th

640
00:26:39.560 --> 00:26:40.920
is well flagged.

641
00:26:41.480 --> 00:26:44.360
Same dust, same geometry, opposite

642
00:26:44.360 --> 00:26:44.880
end of

643
00:26:44.880 --> 00:26:47.480
Anna: the night and the planets from the north.

644
00:26:47.560 --> 00:26:49.960
Avery: The morning sky is where your action is.

645
00:26:50.660 --> 00:26:53.540
Jupiter dominates the pre dawn east and is

646
00:26:53.540 --> 00:26:56.420
closing on Regulus with Mars nearby

647
00:26:56.900 --> 00:26:59.700
high in the east near Castor and Pollux

648
00:26:59.780 --> 00:27:02.620
shortly before sunrise. Saturn is

649
00:27:02.620 --> 00:27:04.900
your evening and overnight object too.

650
00:27:05.380 --> 00:27:08.060
Around 50 degrees up in the south after

651
00:27:08.060 --> 00:27:10.580
midnight. The best it's looked all year.

652
00:27:10.900 --> 00:27:13.340
And for telescope owners there's a nice

653
00:27:13.340 --> 00:27:15.540
Saturn event early Saturday morning.

654
00:27:16.230 --> 00:27:19.190
Dione transits the north polar region around

655
00:27:19.270 --> 00:27:22.070
2:55am M Eastern and

656
00:27:22.070 --> 00:27:25.030
Tethys slides into Saturn's shadow around

657
00:27:25.110 --> 00:27:27.510
2:10. Space weather

658
00:27:28.230 --> 00:27:29.590
quieter than it was.

659
00:27:30.070 --> 00:27:32.910
The convoy of coronal mass ejections From

660
00:27:32.910 --> 00:27:35.430
Active Region 4524

661
00:27:35.830 --> 00:27:38.710
produced a couple of minor G1 storms on

662
00:27:38.710 --> 00:27:41.630
the 8th and 9th and conditions have eased

663
00:27:41.630 --> 00:27:44.470
back to quiet to unsettled as those effects

664
00:27:44.470 --> 00:27:47.190
fade. No storm watch running.

665
00:27:47.430 --> 00:27:50.390
If more arrives it'll be the northern tier of

666
00:27:50.390 --> 00:27:53.150
the United States. The UK and northern

667
00:27:53.150 --> 00:27:55.990
Europe first and Tasmania and the

668
00:27:55.990 --> 00:27:58.230
south island of New Zealand down here.

669
00:27:59.030 --> 00:28:00.150
Anna: Safety passage.

670
00:28:01.109 --> 00:28:03.790
Avery: Yes, and it's in every episode for a

671
00:28:03.790 --> 00:28:06.190
reason. Venus at minus

672
00:28:06.190 --> 00:28:09.190
4.8 is bright enough to find in broad

673
00:28:09.190 --> 00:28:12.150
daylight, which is a real and rewarding thing

674
00:28:12.150 --> 00:28:14.670
to do. And it is also the one

675
00:28:14.670 --> 00:28:17.150
hobby that puts you in the habit of sweeping

676
00:28:17.150 --> 00:28:19.950
the sky near the sun. So

677
00:28:20.270 --> 00:28:22.790
never point binoculars or a telescope

678
00:28:22.790 --> 00:28:25.790
anywhere near the sun without a purpose built

679
00:28:25.950 --> 00:28:28.590
properly fitted solar filter over the front

680
00:28:28.590 --> 00:28:31.470
of the instrument. Eclipse glasses must

681
00:28:31.470 --> 00:28:33.310
be certified to ISO

682
00:28:33.310 --> 00:28:35.950
123122

683
00:28:36.350 --> 00:28:37.710
and even certify.

684
00:28:37.790 --> 00:28:40.350
Glasses are for naked eye use only.

685
00:28:41.180 --> 00:28:44.140
They are not a filter for optics. Putting a

686
00:28:44.140 --> 00:28:46.620
telescope behind them concentrates the light

687
00:28:46.700 --> 00:28:48.540
and they fail instantly.

688
00:28:49.340 --> 00:28:52.260
Anna: And looking ahead, the equinox on

689
00:28:52.260 --> 00:28:52.460
the

690
00:28:52.460 --> 00:28:55.340
Avery: 22nd, spring for us, autumn for

691
00:28:55.340 --> 00:28:55.900
the north.

692
00:28:56.539 --> 00:28:58.980
The harvest moon sits near Saturn in the

693
00:28:58.980 --> 00:29:01.980
Evening sky on the 26th. Then

694
00:29:01.980 --> 00:29:04.460
Saturn's opposition on the 4th of October

695
00:29:04.780 --> 00:29:07.740
and two nights later on the 6th, Saturn. The

696
00:29:07.740 --> 00:29:10.300
pre dawn lunar occultation of Jupiter

697
00:29:10.460 --> 00:29:13.100
which is being billed as the spectacular

698
00:29:13.100 --> 00:29:16.100
event of the year. We'll be building up to

699
00:29:16.100 --> 00:29:17.180
that one properly.

700
00:29:17.900 --> 00:29:20.340
Anna: That's Astronomy daily for Friday, 11

701
00:29:20.340 --> 00:29:23.300
September Magnetars may be half of all the

702
00:29:23.300 --> 00:29:25.620
neutron stars in the galaxy rather than one

703
00:29:25.620 --> 00:29:28.540
in a hundred, which raises the supernova rate

704
00:29:28.540 --> 00:29:30.940
and makes the magnetar engine explanation for

705
00:29:30.940 --> 00:29:33.740
fast radio bursts and super luminous

706
00:29:33.740 --> 00:29:34.940
supernovae affordable.

707
00:29:34.940 --> 00:29:37.570
For the first time. Chariklo's two

708
00:29:37.570 --> 00:29:39.530
tiny rings have changed in opposite

709
00:29:39.530 --> 00:29:42.370
directions in five years. BepiColombo

710
00:29:42.370 --> 00:29:45.210
caught the sun bombarding mercury from 165

711
00:29:45.210 --> 00:29:46.130
kilometres up.

712
00:29:46.770 --> 00:29:49.170
Avery: Europe has bought itself a way home from

713
00:29:49.170 --> 00:29:52.169
orbit for the first time. Parker solar

714
00:29:52.169 --> 00:29:54.930
probe has checked in from its 29th pass

715
00:29:54.930 --> 00:29:57.650
through the sun's atmosphere and there's a

716
00:29:57.650 --> 00:30:00.490
moon and Venus pairing this weekend that the

717
00:30:00.490 --> 00:30:02.570
southern half of the world gets the better

718
00:30:02.570 --> 00:30:03.330
seat for.

719
00:30:04.240 --> 00:30:06.280
Anna: Everything we covered with links to the

720
00:30:06.280 --> 00:30:08.920
papers and the source releases is in the show

721
00:30:08.920 --> 00:30:11.600
notes and at astronomydaily IO,

722
00:30:12.000 --> 00:30:13.640
where you'll also find the full back

723
00:30:13.640 --> 00:30:15.280
catalogue and the newsletter.

724
00:30:15.280 --> 00:30:17.960
Avery: And the contact form on the site is real and

725
00:30:17.960 --> 00:30:20.680
we read it more than one storey in the past

726
00:30:20.680 --> 00:30:22.960
fortnight. Started as a listener question.

727
00:30:24.000 --> 00:30:26.600
You'll find us on X at astrodaily.

728
00:30:26.600 --> 00:30:29.560
Pod Astronomy AstroDailyPod is part

729
00:30:29.560 --> 00:30:32.080
of the bytes.com podcast network.

730
00:30:33.020 --> 00:30:33.740
Anna: I'm Anna.

731
00:30:33.900 --> 00:30:36.900
Avery: And I'm Avery. Clear skies and if

732
00:30:36.900 --> 00:30:39.100
you can get away from the lights tonight, do

733
00:30:39.500 --> 00:30:41.420
it doesn't get darker than this.