Half the Neutron Stars

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Language: en

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Hello and welcome to Astronomy Daily.


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It's Friday, the 11th of September,


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2026.


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This is series 5, episode 191. And I'm


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Anna.


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>> And I'm Avery. Anna, today's lead is a


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paper arguing that one of the rarest,


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strangest objects in the galaxy isn't


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rare at all.


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>> Magnetars.


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neutron stars with magnetic fields so


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strong the number stops meaning anything


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and we know of about 30 of them against


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a few thousand ordinary radio pulsars.


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So the picture has always been exotic


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freakish one in a 100. A new paper in


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nature astronomy says that picture is a


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counting error and the real figure is


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closer to one and two


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>> half of all neutron stars. half. And if


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that's right, it doesn't just reshuffle


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a catalog. It changes how many supernovi


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our galaxy has to be producing, and it


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quietly props up the leading explanation


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for some of the most extreme events in


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the universe, including the fast radio


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bursts we spent yesterday's lead on.


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>> After that, the rings around a small icy


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body 2 billion km away have changed. One


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thickened, one thinned in the space of 5


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years. And the James Webb Space


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Telescope caught it by watching the


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thing pass in front of a star.


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>> A spacecraft skimming 165 km above


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Mercury at the exact moment the sun let


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go of a burst of particles and measuring


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them landing on the surface.


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>> Europe writing a€ 760 million euro check


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for something it has never once been


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able to do. Bring cargo home from orbit.


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And a quick one on Parker Solar Probe


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checking in from its 29th trip through


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the sun's atmosphere.


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>> Plus the sky for both hemispheres. New


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moon was this afternoon. So tonight is


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as dark as September gets. And there's a


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genuinely lovely pairing this weekend


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that the south gets the better view of.


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Let's get into it.


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>> Ready when you are.


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>> Start me at the beginning. What's a


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magnetar?


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>> Start one step further back. A neutron


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star. Take a star 8 to 20 something


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times the mass of the sun, run it out of


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fuel, and the core collapses in about a


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second. What's left is a ball roughly 20


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km across with more mass than the sun


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packed into it. A teaspoon of the


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material weighs about as much as a


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mountain range.


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>> And they come in flavors.


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>> That's the part that matters today.


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We've cataloged them as separate species


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largely because of how we found them.


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There are radio pulsars, the lighthouse


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ones, thousands of them spinning fast


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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


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x-ray dim isolated neutron stars which


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are exactly as boring as they sound. And


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then there are magnetars


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>> which are not boring.


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>> The opposite. A magnetar's magnetic


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field is somewhere around 10 to the 14


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10^ the 15 gaus. Earth's is about half a


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gaus. A hospital MRI about 15,000. So


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something like a quadrillion times


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Earth. And structurally the key point is


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that a magnetar isn't powered by its


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spin the way a pulsar is. It's powered


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by that field decaying. The field is the


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fuel tank.


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>> What does that look like from the


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outside?


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>> Violence. In short bursts, the crust is


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a rigid solid under enormous magnetic


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stress, and every so often it cracks, a


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star quake, and the object releases more


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energy in a fraction of a second than


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the sun manages in a 100,000 years. In


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2004, one of them put out a flare that


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measurably ionized Earth's upper


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atmosphere from 50,000 lighty years


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away. And we know of about 30


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>> about 30 confirmed against several


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thousand radio pulsars, which is where


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the counting error creeps in because


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those two numbers are not measuring the


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same thing.


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>> Explain that.


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>> A radio pulsar is a longived steady


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beacon. It'll beam for tens of millions


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of years. And we've spent 60 years


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building surveys designed to catch


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exactly that. A magnetar is the


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opposite. bright and obvious for a few


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thousand years, powered by a field that


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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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cataloges, 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


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born.


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>> So, how do you count births instead of


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sightings?


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>> You build the galaxy in a computer.


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That's this work. Sela Partardo Arjo and


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Nanda Rehea at the Institute of Space


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Sciences in Barcelona with Michelle


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Ronkey at Astron in the Netherlands and


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Vanessa Greyber at Royal Holloway in


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London published this week in Nature


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Astronomy. It's a population synthesis.


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Assume a distribution of magnetic fields


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and spins at birth. Then evolve the


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whole simulated population forward.


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>> Evolve how?


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>> Three things at once, which is the


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technical advance. the spin down, how


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the rotation bleeds away. The


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magnetoothermal evolution, how the field


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decays and how the crust cools, which


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are coupled to each other. And the


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galactic dynamics, these things get


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kicked at birth by the supernova and


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drift away from where they were born,


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which changes how far off and how


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obscured they look. Then you run the


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simulated population through the same


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detection filters as the real surveys


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and ask which starting assumption


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produces the sky we actually see. And


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the anchor is what? The full catalog.


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>> The tightest anchor is the young end.


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And it's a small number. There are 24


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known isolated neutron stars in our


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galaxy younger than 2,000 years. That's


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the sample where nothing has had time to


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fade. So it's the fairest census we've


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got. And in that sample, magnetars and


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central compact objects together make up


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about 59%.


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>> Nearly six in 10 of the young ones. They


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combine that with a volume limited


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sample of the X-ray dim objects and what


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comes out is a birth fraction for


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magnetars averaging around 50% of the


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entire neutron star population. The


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range depends on what you assume about


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the field distribution at birth. If it


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peaks around 1 * 10 14 g you get 40 to


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70%. If it peaks a bit higher around 2


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1/2 * 10 14 you get 30 to 50. So the


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headline number is about half with


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honest width on it.


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>> About half with width. And Partardo


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Arjo's own framing of why it took this


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long is worth quoting. She says it's


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essential to model the different types


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of isolated neutron star in a unified


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way together with their possible


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evolutionary connections because that's


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what lets you estimate consistently how


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many magnetars form. In other words, the


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mistake was treating four cataloges as


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four species instead of one population


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seen at different stages.


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>> Right? So what breaks if this is true?


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>> Two things. And the first is a lovely


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piece of arithmetic. If half of all


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neutron stars are magnetars and


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magnetars are only visible for a couple


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of thousand years, then to keep the


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observed population topped up, the


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galaxy has to be making neutron stars


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faster than we'd assumed. They derive a


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core collapse supernova rate of about 2


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per century, 2.01, with a generous error


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bar running from about 1 to nearly four.


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And the old number,


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>> the conventional figure has sat at


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roughly 1 to two per century for a long


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time, and estimates have often drifted


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towards the low end. So this pushes the


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galaxy's supernova rate up from a


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completely independent direction. That's


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the part I like. It's not a supernova


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paper and it still lands on the


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supernova rate.


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>> And the second thing,


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>> the second is bigger and it's about the


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rest of the universe. There's a family


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of extreme events nobody can fully


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explain. Super luminous supernova 10 to


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100 times brighter than a normal one.


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The long plateaus in gammaray burst


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afterglows where something keeps


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injecting energy after the explosion


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should be over and fast radio bursts


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>> which was yesterday's lead. From the


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other end, 109 of them used to weigh the


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ordinary matter of the universe. And for


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all three, the leading explanation is


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the same. A newborn magnetar in the


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middle dumping its magnetic energy into


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the debris. We know it's physically


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possible because in 2020, a magnetar in


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our own galaxy, SG1935


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plus 2154, produced a fast radio burst


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and settled that question. So what was


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missing was the supply.


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>> Exactly the supply. A central engine


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model needs there to be enough engines.


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If magnetars were a 1% curiosity, then


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explaining a whole class of common


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extragalactic transients with them is a


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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


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to the models. It doesn't prove them. It


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makes them affordable.


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>> Caveats. Give me the honest ones.


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>> Three. 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


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assumed shape of the birth field


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distribution is wrong, the answer moves.


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The paper is up front that the 50%


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depends on assuming a two peaked field


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distribution at birth. Second, the


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anchor sample is 24 objects. 24. That's


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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, magnetar here is


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defined by a threshold. A dipole field


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above about 10^ the 13.5 G. And nature


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doesn't come with a threshold. Some


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objects sit right on the line.


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>> And where does the work go next?


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>> Ria's answer is the obvious one and also


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the right one. Test it outside our


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galaxy. A natural extension, she says,


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would be to check these results in an


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extragalactic context, which is exactly


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where the transients are.


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>> And there's a southern thread here,


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isn't there?


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>> There's a good one, and it's not


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decorative. It's foundational. The


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entire field of magnetars starts in the


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southern sky. On the 5th of March 1979,


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a burst of gamma rays swept through the


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solar system so hard it saturated


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instruments on nine separate spacecraft.


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And when it was traced back, it came


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from the N49 supernova remnant in the


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large melanic cloud, SG0526US


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666, a southern sky object in a southern


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sky satellite galaxy. That event is the


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reason the word magnetar exists at all.


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>> And the modern end,


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>> the modern end runs through Western


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Australia. In 2022, a survey with the


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Merchesen Widefield Array at Inyaram


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Mana Ilgari Bundara, the same site


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that'll host SKA Low, turned up Gleam


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XJ162759,


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an object switching on for a minute at a


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time every 18 minutes, far too slow for


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anything we thought could produce radio


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emission like that. And the follow-up


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that took that Australian discovery


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seriously as a possible ultra-ong period


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magnetar was led out of the same


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Barcelona group using the same


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magnetoothermal machinery behind today's


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result.


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>> Same tools, same people, southern data,


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>> which is how this actually works. A wide


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field radio survey on Wajari country


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finds something nobody can classify. A


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theory group in Spain builds the model


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that might explain it. And four years


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later, the model tells us we've been


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misounting the whole population.


00:12:09.920 --> 00:12:13.030
>> Story two, and it's small, distant, and


00:12:13.040 --> 00:12:17.030
genuinely strange. Cherlo is a centaur,


00:12:17.040 --> 00:12:19.750
one of the icy bodies on unstable orbits


00:12:19.760 --> 00:12:22.790
between Jupiter and Neptune, in Cherlo's


00:12:22.800 --> 00:12:24.870
case, crossing between Saturn and


00:12:24.880 --> 00:12:29.590
Uranus. It's about 250 km across, so a


00:12:29.600 --> 00:12:32.949
radius of roughly 125, which makes it


00:12:32.959 --> 00:12:36.150
the largest centaur we know of. And in


00:12:36.160 --> 00:12:38.870
2013, it became the first object smaller


00:12:38.880 --> 00:12:41.829
than a planet ever found to have rings.


00:12:41.839 --> 00:12:44.389
>> Found how? You can't image something


00:12:44.399 --> 00:12:46.629
that small at that distance.


00:12:46.639 --> 00:12:49.190
>> You can't. You watch it pass in front of


00:12:49.200 --> 00:12:51.990
a star and time the shadow. A stellar


00:12:52.000 --> 00:12:55.269
occultation. The star blinks out. You


00:12:55.279 --> 00:12:57.750
measure for exactly how long. And from


00:12:57.760 --> 00:12:59.829
telescopes at different sites, you


00:12:59.839 --> 00:13:01.829
reconstruct the shape of whatever passed


00:13:01.839 --> 00:13:05.430
in front. In 2013, a campaign strung


00:13:05.440 --> 00:13:08.389
across Chile, Brazil, Argentina, and


00:13:08.399 --> 00:13:11.269
Uruguay caught Cherlo doing that, and


00:13:11.279 --> 00:13:14.310
the star didn't blink once. It blinked


00:13:14.320 --> 00:13:16.790
twice on the way in and twice on the way


00:13:16.800 --> 00:13:17.829
out.


00:13:17.839 --> 00:13:19.110
>> Rings,


00:13:19.120 --> 00:13:22.150
>> two of them, sharp, narrow, and a


00:13:22.160 --> 00:13:24.870
complete surprise. At the time, rings


00:13:24.880 --> 00:13:27.269
were something planets had. They sit


00:13:27.279 --> 00:13:31.269
about 390 and 405 kilometers from the


00:13:31.279 --> 00:13:34.310
center, a few kilometers wide each, and


00:13:34.320 --> 00:13:36.230
they've been called cheraclo pocket


00:13:36.240 --> 00:13:38.069
rings ever since.


00:13:38.079 --> 00:13:39.990
>> And Web has now looked


00:13:40.000 --> 00:13:43.509
>> Webb looked on the 18th of October 2022,


00:13:43.519 --> 00:13:45.750
the first stellar occultation ever


00:13:45.760 --> 00:13:48.389
specifically planned for the telescope.


00:13:48.399 --> 00:13:51.350
The payoff is wavelength. web sees out


00:13:51.360 --> 00:13:53.990
to five microns in the infrared which


00:13:54.000 --> 00:13:56.230
isn't available from the ground and it


00:13:56.240 --> 00:13:59.030
resolved the rings to about a kilometer.


00:13:59.040 --> 00:14:01.670
Published this week in science advances


00:14:01.680 --> 00:14:05.189
led by UEL kilitz Pablo Santos Sans and


00:14:05.199 --> 00:14:07.189
Celia Nvice at the Institute of


00:14:07.199 --> 00:14:09.829
Astrophysics of Andalusia with Nicholas


00:14:09.839 --> 00:14:13.269
Rambo, Bruno Sicardi and Joselyn Demars


00:14:13.279 --> 00:14:16.069
in Paris. And what changed?


00:14:16.079 --> 00:14:18.949
>> Both rings in opposite directions.


00:14:18.959 --> 00:14:20.389
Compared with the groundbased


00:14:20.399 --> 00:14:25.189
occultations of 2017, the inner ring C1R


00:14:25.199 --> 00:14:29.030
is now about 50% more opaque. The outer


00:14:29.040 --> 00:14:32.870
ring C2R has gone the other way. Its


00:14:32.880 --> 00:14:36.310
opacity has dropped by around 60%. And


00:14:36.320 --> 00:14:39.030
the positions haven't moved at all. The


00:14:39.040 --> 00:14:41.430
rings are where they were. It's the


00:14:41.440 --> 00:14:43.990
material in them that's different. in


00:14:44.000 --> 00:14:45.350
five years.


00:14:45.360 --> 00:14:47.750
>> In five years, around an object that


00:14:47.760 --> 00:14:50.949
takes 63 years to go around the sun.


00:14:50.959 --> 00:14:53.590
That's the finding. These are not static


00:14:53.600 --> 00:14:55.750
structures you can photograph once and


00:14:55.760 --> 00:14:58.790
file away. They're dynamically active on


00:14:58.800 --> 00:15:00.949
a time scale a human being can sit


00:15:00.959 --> 00:15:01.670
through.


00:15:01.680 --> 00:15:02.710
>> What would do that?


00:15:02.720 --> 00:15:05.829
>> Nobody knows yet. And the paper says so.


00:15:05.839 --> 00:15:07.670
The outer ring thinning could be


00:15:07.680 --> 00:15:10.629
straightforward material loss. The inner


00:15:10.639 --> 00:15:12.389
one thickening could be material


00:15:12.399 --> 00:15:15.030
arriving or collisions grinding larger


00:15:15.040 --> 00:15:17.590
particles into finer grains which are


00:15:17.600 --> 00:15:20.470
more opaque per kilogram. And the team


00:15:20.480 --> 00:15:22.629
adds a third possibility that isn't


00:15:22.639 --> 00:15:25.269
astrophysics at all. They're comparing


00:15:25.279 --> 00:15:27.590
infrared measurements with older visible


00:15:27.600 --> 00:15:29.910
light ones. So some of the difference


00:15:29.920 --> 00:15:32.069
could be about what each wavelength is


00:15:32.079 --> 00:15:34.310
sensitive to rather than the rings


00:15:34.320 --> 00:15:37.509
actually changing. So the result is a


00:15:37.519 --> 00:15:41.110
real change, a suspected cause and an


00:15:41.120 --> 00:15:43.269
unresolved confound.


00:15:43.279 --> 00:15:45.590
>> That's a fair summary and it's why the


00:15:45.600 --> 00:15:47.829
next occultation matters more than this


00:15:47.839 --> 00:15:50.470
one. The southern hemisphere point here


00:15:50.480 --> 00:15:52.949
is that this whole technique is ours by


00:15:52.959 --> 00:15:56.310
geography and by habit. Cherlo rings


00:15:56.320 --> 00:15:58.069
were discovered from South American


00:15:58.079 --> 00:16:00.550
soil. Occultation chasing is a


00:16:00.560 --> 00:16:02.550
discipline where a well-placed amateur


00:16:02.560 --> 00:16:04.949
telescope in rural Australia or New


00:16:04.959 --> 00:16:08.069
Zealand can contribute real data and the


00:16:08.079 --> 00:16:10.550
shadow tracks fall where they fall,


00:16:10.560 --> 00:16:12.550
which is often down here.


00:16:12.560 --> 00:16:14.629
>> Story three, and it's a piece of luck


00:16:14.639 --> 00:16:17.829
that turned into a result. Bey Columbo,


00:16:17.839 --> 00:16:19.910
the joint European and Japanese mission


00:16:19.920 --> 00:16:21.910
to Mercury, which we've been following


00:16:21.920 --> 00:16:24.150
as it comes in to arrive, made its


00:16:24.160 --> 00:16:26.310
fourth flyby of the planet in September


00:16:26.320 --> 00:16:30.949
2024. And it came in low, 165 km above


00:16:30.959 --> 00:16:32.150
the surface,


00:16:32.160 --> 00:16:34.150
>> which is closer than it'll be when it's


00:16:34.160 --> 00:16:35.509
actually in orbit,


00:16:35.519 --> 00:16:37.269
>> closer than the science orbit, which is


00:16:37.279 --> 00:16:40.069
the point the team keeps making. And at


00:16:40.079 --> 00:16:42.550
the exact moment it was down there, the


00:16:42.560 --> 00:16:44.790
sun let go of a major eruption of


00:16:44.800 --> 00:16:47.509
energetic particles. The lead author,


00:16:47.519 --> 00:16:50.150
Kilpua, at the University of Helsinki,


00:16:50.160 --> 00:16:52.710
puts it plainly, "The fourth flyby was


00:16:52.720 --> 00:16:55.030
unique. The spacecraft was much closer


00:16:55.040 --> 00:16:56.870
to the surface than it will ever be in


00:16:56.880 --> 00:16:59.189
its final orbit." And they were lucky


00:16:59.199 --> 00:17:01.350
that a major particle eruption happened


00:17:01.360 --> 00:17:04.069
on the sun at precisely that moment.


00:17:04.079 --> 00:17:06.309
>> So what did it see? It watched the


00:17:06.319 --> 00:17:08.309
particles get through. High energy


00:17:08.319 --> 00:17:10.150
electrons and protons penetrated


00:17:10.160 --> 00:17:11.990
Mercury's magnetic field and


00:17:12.000 --> 00:17:14.069
precipitated onto the surface across a


00:17:14.079 --> 00:17:16.230
wide area. The instrument is called


00:17:16.240 --> 00:17:19.270
Sixus, the solar intensity X-ray and


00:17:19.280 --> 00:17:21.510
particle spectrometer designed and built


00:17:21.520 --> 00:17:23.909
in Finland and the work has just been


00:17:23.919 --> 00:17:26.069
published in Nature Astronomy.


00:17:26.079 --> 00:17:28.630
>> Why does it matter where particles land?


00:17:28.640 --> 00:17:31.110
>> Two reasons and the first is practical.


00:17:31.120 --> 00:17:33.110
When energetic particles hit an airless


00:17:33.120 --> 00:17:35.430
surface, they knock atoms and molecules


00:17:35.440 --> 00:17:37.750
off it and they make the surface fluores


00:17:37.760 --> 00:17:40.470
in X-rays. That fluoresence is exactly


00:17:40.480 --> 00:17:42.230
how you read the chemical composition of


00:17:42.240 --> 00:17:44.549
a planet you can't land on. So, if you


00:17:44.559 --> 00:17:46.710
want to map what Mercury is made of, you


00:17:46.720 --> 00:17:48.310
need to know what's bombarding it and


00:17:48.320 --> 00:17:50.390
where. This is calibration for the


00:17:50.400 --> 00:17:52.230
mission's own science.


00:17:52.240 --> 00:17:53.110
>> And the second


00:17:53.120 --> 00:17:56.070
>> the second is that it's weathering over


00:17:56.080 --> 00:17:58.870
geological time. That bombardment is one


00:17:58.880 --> 00:18:01.430
of the things reworking the surface


00:18:01.440 --> 00:18:03.270
along with the solar wind and


00:18:03.280 --> 00:18:05.190
micrometeorites.


00:18:05.200 --> 00:18:07.190
And there's a third payoff that reaches


00:18:07.200 --> 00:18:10.549
back here. Rammy Vineo at the University


00:18:10.559 --> 00:18:13.510
of Turu, the co-investigator, makes the


00:18:13.520 --> 00:18:15.830
point that Mercury has a real magnetic


00:18:15.840 --> 00:18:20.070
field, but a small weak magnetosphere,


00:18:20.080 --> 00:18:22.230
which makes it a natural standin for


00:18:22.240 --> 00:18:24.789
what Earth looks like during an extreme


00:18:24.799 --> 00:18:28.230
solar storm. Mercury is the experiment


00:18:28.240 --> 00:18:30.950
we can't run on ourselves.


00:18:30.960 --> 00:18:33.510
>> And where is the spacecraft now?


00:18:33.520 --> 00:18:35.350
>> In the middle of the most interesting


00:18:35.360 --> 00:18:38.230
stretch of its life. It separated its


00:18:38.240 --> 00:18:40.710
transfer module, the big electric


00:18:40.720 --> 00:18:42.549
propulsion stack that's been doing the


00:18:42.559 --> 00:18:44.950
work for 8 years on the 3rd of


00:18:44.960 --> 00:18:47.990
September, 8 days ago. Gravity capture


00:18:48.000 --> 00:18:50.950
at Mercury is on the 21st of November.


00:18:50.960 --> 00:18:53.669
The Japanese orbiter Mio gets released


00:18:53.679 --> 00:18:55.990
around the 9th or 10th of December. And


00:18:56.000 --> 00:18:58.230
the European orbiter reaches its final


00:18:58.240 --> 00:19:00.630
science orbit in March with routine


00:19:00.640 --> 00:19:03.350
science from April. So this flyby result


00:19:03.360 --> 00:19:05.750
is arriving as a kind of advanced sample


00:19:05.760 --> 00:19:07.510
of what the mission is about to start


00:19:07.520 --> 00:19:09.110
doing properly.


00:19:09.120 --> 00:19:11.750
>> Story four. And it's money rather than


00:19:11.760 --> 00:19:14.390
physics. But it's the kind of money that


00:19:14.400 --> 00:19:17.270
changes what's possible. Yesterday, the


00:19:17.280 --> 00:19:19.990
European Space Agency awarded a contract


00:19:20.000 --> 00:19:22.310
worth up to€760


00:19:22.320 --> 00:19:24.950
million euros to a German startup called


00:19:24.960 --> 00:19:27.750
the Exploration Company to build a


00:19:27.760 --> 00:19:30.230
spacecraft that can carry cargo to the


00:19:30.240 --> 00:19:33.190
International Space Station. And this is


00:19:33.200 --> 00:19:35.990
the part Europe has never done. Bring it


00:19:36.000 --> 00:19:37.029
back.


00:19:37.039 --> 00:19:39.590
>> Never. Europe flew cargo to the station


00:19:39.600 --> 00:19:40.950
for years.


00:19:40.960 --> 00:19:44.630
>> Flew it up. Yes. The ATVs, five of them,


00:19:44.640 --> 00:19:47.510
big and successful, every one of them


00:19:47.520 --> 00:19:49.590
was then deliberately destroyed on the


00:19:49.600 --> 00:19:52.470
way down. Europe has never returned


00:19:52.480 --> 00:19:55.190
anything from orbit to the ground. That


00:19:55.200 --> 00:19:57.909
capability belongs to the United States,


00:19:57.919 --> 00:20:00.470
Russia, and China. And it's the


00:20:00.480 --> 00:20:02.549
difference between shipping and shipping


00:20:02.559 --> 00:20:05.590
both ways. Experiments you can actually


00:20:05.600 --> 00:20:08.630
get back, hardware you can inspect,


00:20:08.640 --> 00:20:11.350
samples that survive. What's the shape


00:20:11.360 --> 00:20:12.549
of the deal?


00:20:12.559 --> 00:20:15.190
>> It runs under a program issa calls


00:20:15.200 --> 00:20:18.710
Aladdin. And the structure is €310


00:20:18.720 --> 00:20:21.590
million for the demonstration mission


00:20:21.600 --> 00:20:24.950
with ISSA covering 60% of that and the


00:20:24.960 --> 00:20:29.350
company funding the other 40 plus €450


00:20:29.360 --> 00:20:31.590
million in options for two further


00:20:31.600 --> 00:20:35.029
missions. The vehicle is called Nyx. It


00:20:35.039 --> 00:20:38.390
flies on Aron 6 and it has to dock with


00:20:38.400 --> 00:20:40.549
the space station no later than the


00:20:40.559 --> 00:20:43.270
second quarter of 2029.


00:20:43.280 --> 00:20:46.070
There's also up to 50 million euros in


00:20:46.080 --> 00:20:47.990
additional incentive for flying on


00:20:48.000 --> 00:20:50.789
European launch vehicles which tells you


00:20:50.799 --> 00:20:53.590
what else this contract is really for.


00:20:53.600 --> 00:20:55.270
>> And the company is how old?


00:20:55.280 --> 00:20:58.710
>> Founded in 2021, their chief executive


00:20:58.720 --> 00:21:01.190
Ellen Hubie is quite direct about how


00:21:01.200 --> 00:21:04.149
unusual that is. She says it's the first


00:21:04.159 --> 00:21:06.390
time in Europe that a 5-year-old space


00:21:06.400 --> 00:21:08.310
startup has won a contract worth


00:21:08.320 --> 00:21:11.510
hundreds of millions of euros. ESA's


00:21:11.520 --> 00:21:14.070
Daniel Nuenwander frames it as getting


00:21:14.080 --> 00:21:16.789
Europe one step closer to a capability


00:21:16.799 --> 00:21:19.510
only a handful of nations have mastered


00:21:19.520 --> 00:21:22.070
and it's worth noting ESA hasn't closed


00:21:22.080 --> 00:21:24.549
the door on the alternative. Fails


00:21:24.559 --> 00:21:27.270
Alenia space in Italy is still in a


00:21:27.280 --> 00:21:28.710
parallel tender.


00:21:28.720 --> 00:21:31.830
>> Has the company flown anything? It has.


00:21:31.840 --> 00:21:34.950
And this is the honest caveat. In June


00:21:34.960 --> 00:21:38.149
2025, they flew a small re-entry capsule


00:21:38.159 --> 00:21:41.029
called Mission Possible as a ride share.


00:21:41.039 --> 00:21:43.669
It launched. It operated in orbit. It


00:21:43.679 --> 00:21:46.470
survived re-entry and then contact was


00:21:46.480 --> 00:21:49.029
lost shortly before splashdown and the


00:21:49.039 --> 00:21:51.590
capsule was not recovered. The company


00:21:51.600 --> 00:21:53.990
called it a partial success, which is


00:21:54.000 --> 00:21:56.789
fair in both directions. So the jump


00:21:56.799 --> 00:21:58.630
from that to docking with the space


00:21:58.640 --> 00:22:01.110
station and returning intact is a very


00:22:01.120 --> 00:22:03.669
large one on a fixed timeline.


00:22:03.679 --> 00:22:05.590
>> And the strategic read,


00:22:05.600 --> 00:22:07.750
>> it's the same thread we were pulling on


00:22:07.760 --> 00:22:10.549
6 days ago with ESAR Aerospace reaching


00:22:10.559 --> 00:22:13.830
orbit from Norway. Within one Fortnite,


00:22:13.840 --> 00:22:15.750
Europe has launched to orbit from its


00:22:15.760 --> 00:22:18.149
own soil for the first time and bought


00:22:18.159 --> 00:22:20.950
itself a route home. The target isn't


00:22:20.960 --> 00:22:23.990
really the space station either. The ISS


00:22:24.000 --> 00:22:26.470
has a handful of years left. It's


00:22:26.480 --> 00:22:28.870
whatever commercial stations replace it


00:22:28.880 --> 00:22:31.029
and who gets to service them.


00:22:31.039 --> 00:22:33.510
>> One quick one before the sky. NASA's


00:22:33.520 --> 00:22:35.750
Parker Solar Probe has reported in after


00:22:35.760 --> 00:22:38.310
its 29th close approach to the sun,


00:22:38.320 --> 00:22:40.950
which it made on the 4th of September.


00:22:40.960 --> 00:22:42.789
>> Still holding the record.


00:22:42.799 --> 00:22:44.870
>> Still holding it. And that's now the


00:22:44.880 --> 00:22:49.430
eighth time it has 430,000 mph, about


00:22:49.440 --> 00:22:53.750
690,000 km an hour. and 3.8 million


00:22:53.760 --> 00:22:55.669
miles from the surface, which are


00:22:55.679 --> 00:22:57.510
exactly the numbers it set on Christmas


00:22:57.520 --> 00:23:00.789
Eve 2024. It's not going faster or


00:23:00.799 --> 00:23:02.870
closer. It's repeating the same


00:23:02.880 --> 00:23:05.510
extraordinary pass over and over, which


00:23:05.520 --> 00:23:07.110
is the whole design.


00:23:07.120 --> 00:23:09.590
>> And it goes silent while it does it


00:23:09.600 --> 00:23:11.909
>> completely. The encounter ran from the


00:23:11.919 --> 00:23:14.549
30th of August to the 9th of September.


00:23:14.559 --> 00:23:16.630
And for 9 days of that, it's on its own


00:23:16.640 --> 00:23:19.270
with no contact, too close to the sun to


00:23:19.280 --> 00:23:21.430
talk. It sent a beacon tone on the


00:23:21.440 --> 00:23:23.669
seventh to say it was healthy. This


00:23:23.679 --> 00:23:25.430
particular pass was aimed at the north


00:23:25.440 --> 00:23:27.590
pole of the sun, looking at structures


00:23:27.600 --> 00:23:29.909
and activity up there. And in one day,


00:23:29.919 --> 00:23:32.310
it sweeps through nearly 40% of the


00:23:32.320 --> 00:23:34.070
solar circumference.


00:23:34.080 --> 00:23:36.070
>> When do we see anything?


00:23:36.080 --> 00:23:38.390
>> Telemetry started flowing today and the


00:23:38.400 --> 00:23:40.630
science data comes down between the 13th


00:23:40.640 --> 00:23:43.430
and the 27th and the mission itself has


00:23:43.440 --> 00:23:46.310
been extended through 2029 after this


00:23:46.320 --> 00:23:48.950
year's helopysics review. So, there's


00:23:48.960 --> 00:23:50.390
plenty more of this to come.


00:23:50.400 --> 00:23:53.029
>> And to the sky. And this is a good


00:23:53.039 --> 00:23:56.230
weekend for a simple reason. New moon


00:23:56.240 --> 00:23:59.590
fell this afternoon, Sydney time, at 27


00:23:59.600 --> 00:24:02.630
minutes past 2. Which means tonight and


00:24:02.640 --> 00:24:04.789
tomorrow night are the darkest of the


00:24:04.799 --> 00:24:07.750
month. And the moon comes back as a thin


00:24:07.760 --> 00:24:10.149
evening crescent just in time to do


00:24:10.159 --> 00:24:11.830
something pretty.


00:24:11.840 --> 00:24:14.070
>> Southern hemisphere. First


00:24:14.080 --> 00:24:16.950
>> from Sydney and similar latitudes. Venus


00:24:16.960 --> 00:24:19.190
is the evening object and it wants


00:24:19.200 --> 00:24:21.830
dealing with promptly low in the west


00:24:21.840 --> 00:24:24.549
after sunset and setting quickly. So the


00:24:24.559 --> 00:24:27.590
window is the first 45 minutes once the


00:24:27.600 --> 00:24:30.549
sky darkens. Worth the trouble because


00:24:30.559 --> 00:24:32.149
it's building towards greatest


00:24:32.159 --> 00:24:35.029
brilliancancy on the 18th at magnitude


00:24:35.039 --> 00:24:36.870
minus4.8


00:24:36.880 --> 00:24:40.470
about as bright as Venus ever gets. and


00:24:40.480 --> 00:24:42.710
the pairing you mentioned.


00:24:42.720 --> 00:24:45.830
>> Sunday and Monday evening, the 13th and


00:24:45.840 --> 00:24:49.750
14th, a very thin waxing crescent sweeps


00:24:49.760 --> 00:24:52.470
past Venus. And on the 14th, they're


00:24:52.480 --> 00:24:55.430
about half a degree apart. That's a moon


00:24:55.440 --> 00:24:58.390
width. Spya is right there, too. So,


00:24:58.400 --> 00:25:00.789
there's a third point in the picture.


00:25:00.799 --> 00:25:03.909
And this one is genuinely ours. Earth's


00:25:03.919 --> 00:25:05.909
sky's own note is that the southern


00:25:05.919 --> 00:25:08.789
hemisphere gets the better view. Find a


00:25:08.799 --> 00:25:11.750
clear low western horizon and look as


00:25:11.760 --> 00:25:14.789
soon as the sky starts to color.


00:25:14.799 --> 00:25:16.230
>> Saturn.


00:25:16.240 --> 00:25:18.149
>> Saturn is the reliable one for


00:25:18.159 --> 00:25:20.789
everybody. Rising in the east not long


00:25:20.799 --> 00:25:23.830
after sunset, well up by mid evening,


00:25:23.840 --> 00:25:25.830
heading for opposition on the 4th of


00:25:25.840 --> 00:25:29.590
October with the rings about 7° open.


00:25:29.600 --> 00:25:32.310
And with no moon in the sky, the core of


00:25:32.320 --> 00:25:34.870
the Milky Way is still high after dark


00:25:34.880 --> 00:25:37.830
down here. Sagittarius and Scorpius


00:25:37.840 --> 00:25:40.470
overhead in the early evening. The best


00:25:40.480 --> 00:25:43.510
naked eye view in the sky and hours for


00:25:43.520 --> 00:25:45.750
a few more weeks.


00:25:45.760 --> 00:25:47.830
>> There's one more southern thing and it's


00:25:47.840 --> 00:25:49.190
subtle.


00:25:49.200 --> 00:25:52.070
>> The zodiacal light, sunlight scattered


00:25:52.080 --> 00:25:53.990
off dust in the plane of the solar


00:25:54.000 --> 00:25:56.390
system, looking like a faint pyramid


00:25:56.400 --> 00:25:59.029
leaning up from the horizon. It's an


00:25:59.039 --> 00:26:01.750
equinox phenomenon. And right now in the


00:26:01.760 --> 00:26:03.750
southern hemisphere, it's an evening


00:26:03.760 --> 00:26:06.789
object. Look west after true darkness


00:26:06.799 --> 00:26:09.830
and it's often called the false dusk.


00:26:09.840 --> 00:26:12.310
You need a properly dark sight and no


00:26:12.320 --> 00:26:14.870
moon which is precisely what this week


00:26:14.880 --> 00:26:17.430
gives you. It runs through to early


00:26:17.440 --> 00:26:19.029
November.


00:26:19.039 --> 00:26:21.830
>> North America, your turn. And you get


00:26:21.840 --> 00:26:23.590
the same thing at the other end of the


00:26:23.600 --> 00:26:24.710
night.


00:26:24.720 --> 00:26:27.350
>> You do. For the northern hemisphere in


00:26:27.360 --> 00:26:29.750
September, the zodiacal light is a


00:26:29.760 --> 00:26:32.789
pre-dawn object. Look east in the couple


00:26:32.799 --> 00:26:35.269
of hours before sunrise and it's called


00:26:35.279 --> 00:26:38.630
the false dawn for the obvious reason.


00:26:38.640 --> 00:26:41.909
Around the 15th is well flagged. Same


00:26:41.919 --> 00:26:45.190
dust, same geometry, opposite end of the


00:26:45.200 --> 00:26:46.310
night


00:26:46.320 --> 00:26:47.830
>> and the planets from the north.


00:26:47.840 --> 00:26:50.710
>> The morning sky is where your action is.


00:26:50.720 --> 00:26:53.430
Jupiter dominates the pre-dawn east and


00:26:53.440 --> 00:26:57.110
is closing on Regulus with Mars nearby,


00:26:57.120 --> 00:26:59.990
high in the east near Caster and Pollock


00:27:00.000 --> 00:27:02.950
shortly before sunrise. Saturn is your


00:27:02.960 --> 00:27:06.070
evening and overnight object too around


00:27:06.080 --> 00:27:09.190
50° up in the south after midnight, the


00:27:09.200 --> 00:27:11.590
best it's looked all year. And for


00:27:11.600 --> 00:27:13.990
telescope owners, there's a nice Saturn


00:27:14.000 --> 00:27:17.029
event early Saturday morning. Dion


00:27:17.039 --> 00:27:19.510
transits the north polear region around


00:27:19.520 --> 00:27:23.830
2:55 a.m. Eastern and Tethus slides into


00:27:23.840 --> 00:27:26.870
Saturn's shadow around 210.


00:27:26.880 --> 00:27:28.470
>> Space weather


00:27:28.480 --> 00:27:31.269
>> quieter than it was. The convoy of


00:27:31.279 --> 00:27:33.510
coronal mass ejections from active


00:27:33.520 --> 00:27:35.990
region 4524


00:27:36.000 --> 00:27:38.870
produced a couple of minor G1 storms on


00:27:38.880 --> 00:27:41.350
the 8th and 9th and conditions have


00:27:41.360 --> 00:27:43.830
eased back to quiet to unsettled as


00:27:43.840 --> 00:27:46.789
those effects fade. No storm watch


00:27:46.799 --> 00:27:49.590
running. If more arrives, it'll be the


00:27:49.600 --> 00:27:51.990
northern tier of the United States, the


00:27:52.000 --> 00:27:54.789
UK and Northern Europe first, and


00:27:54.799 --> 00:27:57.269
Tasmania and the South Island of New


00:27:57.279 --> 00:27:59.269
Zealand down here.


00:27:59.279 --> 00:28:01.269
>> Safety passage.


00:28:01.279 --> 00:28:03.990
>> Yes. And it's in every episode for a


00:28:04.000 --> 00:28:07.430
reason. Venus at minus4.8


00:28:07.440 --> 00:28:09.350
is bright enough to find in broad


00:28:09.360 --> 00:28:11.990
daylight, which is a real and rewarding


00:28:12.000 --> 00:28:14.789
thing to do. And it is also the one


00:28:14.799 --> 00:28:16.789
hobby that puts you in the habit of


00:28:16.799 --> 00:28:20.789
sweeping the sky near the sun. So never


00:28:20.799 --> 00:28:23.350
point binoculars or a telescope anywhere


00:28:23.360 --> 00:28:26.149
near the sun without a purpose-built,


00:28:26.159 --> 00:28:28.549
properly fitted solar filter over the


00:28:28.559 --> 00:28:31.350
front of the instrument. Eclipse glasses


00:28:31.360 --> 00:28:36.630
must be certified to ISO 12312-2


00:28:36.640 --> 00:28:39.430
and even certified glasses are for naked


00:28:39.440 --> 00:28:42.710
eye use only. They are not a filter for


00:28:42.720 --> 00:28:45.590
optics. Putting a telescope behind them


00:28:45.600 --> 00:28:47.990
concentrates the light and they fail


00:28:48.000 --> 00:28:49.510
instantly.


00:28:49.520 --> 00:28:51.269
And looking ahead,


00:28:51.279 --> 00:28:54.870
>> the equinox on the 22nd, spring for us,


00:28:54.880 --> 00:28:57.669
autumn for the north, the harvest moon


00:28:57.679 --> 00:29:00.230
sits near Saturn in the evening sky on


00:29:00.240 --> 00:29:03.510
the 26th. Then Saturn's opposition on


00:29:03.520 --> 00:29:06.389
the 4th of October and two nights later


00:29:06.399 --> 00:29:08.950
on the 6th, the pre-dawn lunar


00:29:08.960 --> 00:29:11.510
occultation of Jupiter, which is being


00:29:11.520 --> 00:29:14.070
buil as the spectacular event of the


00:29:14.080 --> 00:29:16.710
year. We'll be building up to that one


00:29:16.720 --> 00:29:18.070
properly.


00:29:18.080 --> 00:29:19.909
That's Astronomy Daily for Friday the


00:29:19.919 --> 00:29:22.950
11th of September. Magnetars may be half


00:29:22.960 --> 00:29:25.110
of all the neutron stars in the galaxy


00:29:25.120 --> 00:29:27.590
rather than one in a 100, which raises


00:29:27.600 --> 00:29:29.269
the supernova rate and makes the


00:29:29.279 --> 00:29:31.510
magnetar engine explanation for fast


00:29:31.520 --> 00:29:33.830
radio bursts and super luminous


00:29:33.840 --> 00:29:36.710
supernovi affordable for the first time.


00:29:36.720 --> 00:29:39.269
Cherlo's two tiny rings have changed in


00:29:39.279 --> 00:29:41.990
opposite directions in 5 years. Bey


00:29:42.000 --> 00:29:43.669
Columbo caught the sun bombarding


00:29:43.679 --> 00:29:47.590
Mercury from 165 km up. Europe has


00:29:47.600 --> 00:29:49.990
bought itself a way home from orbit for


00:29:50.000 --> 00:29:52.950
the first time. Parker Solar Probe has


00:29:52.960 --> 00:29:55.350
checked in from its 29th pass through


00:29:55.360 --> 00:29:58.070
the sun's atmosphere. And there's a moon


00:29:58.080 --> 00:30:00.630
and Venus pairing this weekend that the


00:30:00.640 --> 00:30:02.470
southern half of the world gets the


00:30:02.480 --> 00:30:04.310
better seat for.


00:30:04.320 --> 00:30:06.389
>> Everything we covered with links to the


00:30:06.399 --> 00:30:08.870
papers and the source releases is in the


00:30:08.880 --> 00:30:12.149
show notes and at astronomyaily.io io


00:30:12.159 --> 00:30:13.830
where you'll also find the fullback


00:30:13.840 --> 00:30:15.430
catalog and the newsletter.


00:30:15.440 --> 00:30:17.830
>> And the contact form on the site is real


00:30:17.840 --> 00:30:20.470
and we read it. More than one story in


00:30:20.480 --> 00:30:22.789
the past Fortnite started as a listener


00:30:22.799 --> 00:30:26.389
question. You'll find us on X at Astro


00:30:26.399 --> 00:30:29.830
Daily Pod. Astronomy Daily is part of


00:30:29.840 --> 00:30:33.110
the Bites.com podcast network.


00:30:33.120 --> 00:30:34.149
>> I'm Anna


00:30:34.159 --> 00:30:37.190
>> and I'm Avery. Clear skies and if you


00:30:37.200 --> 00:30:39.750
can get away from the lights tonight, do


00:30:39.760 --> 00:30:41.990
it. Doesn't get darker than this.


00:30:42.000 --> 00:30:45.110
Astronomy day.


00:30:45.120 --> 00:30:53.110
Stories been told.


00:30:53.120 --> 00:30:56.840
Stories to tell.