Hide and Seek - The Faintest Planet Ever Imaged, Pluto's Landslides & Starlink's 355,000 Dodges
Astronomy Daily: Space News July 16, 2026x
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00:19:2417.82 MB

Hide and Seek - The Faintest Planet Ever Imaged, Pluto's Landslides & Starlink's 355,000 Dodges

AnnaAnnaHost
Anna and Avery kick off with a decade-long game of cosmic hide-and-seek that has finally ended: Beta Pictoris d, the faintest exoplanet ever directly imaged from Earth, found lurking in more than ten years of archival images — and orbiting a star in the southern constellation Pictor. Then it's the completion of VLASS, the sharpest radio map of the whole sky ever made, arriving just as the Rubin Observatory's optical survey switches on. The James Webb Space Telescope has caught a supermassive black hole feeding itself in the Centaurus Cluster — the missing link in a decades-old mystery. A Pluto system double bill follows: the first landslides ever identified on Pluto, and evidence written in Charon's mountains that the big moon once spun more than ten times faster than it does today — both delivered by New Horizons data from 2015. Finally, SpaceX's latest FCC filing reveals Starlink satellites made over 355,000 collision-avoidance manoeuvres in the past year — nearly one dodge per satellite per week — and experts are warning about where the trend leads. Plus dark-sky Southern Hemisphere stargazing and a Starship Flight 13 launch reminder. Chapters • 00:00 — Intro & billboard • 01:30 — Beta Pictoris d: the faintest exoplanet ever imaged from Earth • 05:30 — VLASS complete: the sharpest radio map of the sky • 08:45 — JWST reveals how supermassive black holes feed • 12:15 — Pluto has landslides (Pluto double, part 1) • 15:00 — Charon's slowing spin (Pluto double, part 2) • 17:45 — Starlink's 355,000 collision dodges in a year • 20:45 — Southern Hemisphere skywatch + Starship Flight 13 reminder • 22:30 — Outro Story sources • Beta Pictoris d: ESO release eso2609 (eso.org) · The Astrophysical Journal Letters · space.com · phys.org • VLASS completion: NRAO release (public.nrao.edu/news/vlass-observations-complete) · phys.org • JWST / NGC 4696: Université de Montréal · The Astrophysical Journal Letters · phys.org / EurekAlert • Pluto landslides: Icarus (Discenza et al. 2026) · phys.org · Discover Magazine · Science News • Charon despinning: Nature Communications (Chen et al. 2026, DOI 10.1038/s41467-026-75069-7) · phys.org · Gizmodo • Starlink manoeuvres: SpaceX semiannual FCC constellation status report, via space.com Boilerplate Astronomy Daily is part of the Bitesz.com Podcast Network. Show notes, links and the full back catalogue at astronomydaily.io. Follow @AstroDailyPod on X, Instagram, TikTok and Tumblr. New episodes every day.

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00:00:00 --> 00:00:02 Anna: Welcome to Astronomy Daily, your daily dose

00:00:02 --> 00:00:05 of space and astronomy news. I'm Anna.

00:00:06 --> 00:00:08 Avery: And I'm, um, avery. It's Thursday, the 16th

00:00:08 --> 00:00:11 of July, 2026, and we have a

00:00:11 --> 00:00:14 genuinely lovely lineup for you today,

00:00:14 --> 00:00:17 including a story that's been 10 years in the

00:00:17 --> 00:00:19 making, or more accurately, 10 years in the

00:00:19 --> 00:00:20 hiding.

00:00:20 --> 00:00:23 Anna: That's Our lead astronomers have finally

00:00:23 --> 00:00:25 caught a planet that's been playing hide and

00:00:25 --> 00:00:28 seek with them for over a decade. And it

00:00:28 --> 00:00:31 turns out to be the faintest exoplanet ever

00:00:31 --> 00:00:33 imaged from Earth. And it lives in a southern

00:00:33 --> 00:00:36 constellation, which makes it feel just a

00:00:36 --> 00:00:37 little bit like ours.

00:00:37 --> 00:00:40 Avery: We've also got the completion of a nine year

00:00:40 --> 00:00:42 project to build the sharpest radio map of

00:00:42 --> 00:00:45 the entire sky. And the James Webb Space

00:00:45 --> 00:00:48 Telescope catching a supermassive black hole

00:00:48 --> 00:00:50 in the act of feeding itself.

00:00:50 --> 00:00:53 Anna: Then it's a double bill from the outer solar

00:00:53 --> 00:00:56 system. Landslides on Pluto spotted for

00:00:56 --> 00:00:59 the first time, and evidence that Pluto's big

00:00:59 --> 00:01:01 moon, Charon, once spun more than 10

00:01:01 --> 00:01:03 times faster than it does today.

00:01:04 --> 00:01:06 Avery: And we'll wrap the news with some sobering

00:01:06 --> 00:01:09 numbers. SpaceX's Starlink satellites had

00:01:09 --> 00:01:11 to dodge potential collisions more than

00:01:11 --> 00:01:14 355 times

00:01:14 --> 00:01:17 in the past year. We'll unpack what that

00:01:17 --> 00:01:18 means for everyone's

00:01:18 --> 00:01:21 Anna: orbit, plus your Southern hemisphere sky

00:01:21 --> 00:01:23 watching for tonight. Let's get into it.

00:01:23 --> 00:01:25 Avery, cast your mind.

00:01:25 --> 00:01:27 Back in 2008, astronomers

00:01:27 --> 00:01:30 directly imaged a planet around the young

00:01:30 --> 00:01:33 star Beta Pictoris, one of the very first

00:01:33 --> 00:01:36 exoplanets ever photographed. That was

00:01:36 --> 00:01:38 Beta Pictoris B. A second planet

00:01:38 --> 00:01:41 C followed. And ever since, there's been a,

00:01:41 --> 00:01:44 uh, nagging suspicion that the system was

00:01:44 --> 00:01:44 hiding

00:01:44 --> 00:01:46 Avery: something more because of the disk. Right.

00:01:47 --> 00:01:49 Beta Pictoris has this magnificent debris,

00:01:49 --> 00:01:51 uh, disk. It's the poster child for planet

00:01:51 --> 00:01:54 formation. And parts of it were warped and

00:01:54 --> 00:01:56 sculpted in ways that two known planets

00:01:56 --> 00:01:57 couldn't fully explain.

00:01:58 --> 00:02:01 Anna: Exactly. And now we know why. In a

00:02:01 --> 00:02:02 study published Wednesday in the

00:02:02 --> 00:02:05 Astrophysical Journal Letters, a team using

00:02:05 --> 00:02:08 the European Southern Observatory's Very

00:02:08 --> 00:02:11 Large Telescope in Chile has confirmed a

00:02:11 --> 00:02:13 third planet, Beta Pictoris D.

00:02:13 --> 00:02:16 And here's the headline. It's roughly

00:02:16 --> 00:02:19 100 times fainter than Beta Pictoris

00:02:19 --> 00:02:22 B, which makes it the faintest exoplanet

00:02:22 --> 00:02:24 ever directly imaged from Earth.

00:02:25 --> 00:02:27 Avery: A hundred times fainter. To put that in

00:02:27 --> 00:02:30 context for everyone, direct imaging means

00:02:30 --> 00:02:32 actually capturing the planet's own light in

00:02:32 --> 00:02:34 a photograph next to a star that's

00:02:34 --> 00:02:37 overwhelmingly brighter. It's often compared

00:02:37 --> 00:02:40 to spotting a firefly next to a lighthouse.

00:02:40 --> 00:02:43 This is spotting a very Dim

00:02:43 --> 00:02:43 firefly.

00:02:44 --> 00:02:47 Anna: And the discovery itself was serendipitous.

00:02:47 --> 00:02:50 Ben Sutliff at the University of Edinburgh

00:02:50 --> 00:02:52 who co led the study, said they were

00:02:52 --> 00:02:55 originally just going back to study the known

00:02:55 --> 00:02:57 planet Beta Pictoris B to see how it

00:02:57 --> 00:03:00 changed over time. But in their new images

00:03:00 --> 00:03:03 from the VLT's Eris instrument, there was

00:03:03 --> 00:03:05 something else. A faint point of light

00:03:05 --> 00:03:08 separated from Planet B that sent them down

00:03:08 --> 00:03:10 an entirely new path.

00:03:10 --> 00:03:12 Avery: And this is where the hide and seek comes in.

00:03:13 --> 00:03:15 Once they knew what to look for, they trawled

00:03:15 --> 00:03:17 back through the archives. And there it was,

00:03:17 --> 00:03:20 lurking. In more than a decade of old

00:03:20 --> 00:03:22 observations from the VLT SPEAR instrument

00:03:23 --> 00:03:25 and even in James Webb Space Telescope data,

00:03:25 --> 00:03:28 the planet had been photographed for years.

00:03:28 --> 00:03:30 Nobody had noticed.

00:03:30 --> 00:03:33 Anna: Co author Jane Burkeby at Oxford put it

00:03:33 --> 00:03:36 beautifully. Planet D has been playing hide

00:03:36 --> 00:03:38 and seek with us for over a decade and now

00:03:38 --> 00:03:40 we can say found you.

00:03:40 --> 00:03:42 Avery: So what do we know about the world itself?

00:03:43 --> 00:03:46 Anna: It's a gas giant about 2.4 times

00:03:46 --> 00:03:48 the mass of Jupiter, which sounds big, but

00:03:48 --> 00:03:50 is actually the lightweight of the family.

00:03:51 --> 00:03:54 Planets B and c are each 10 Jupiter

00:03:54 --> 00:03:57 masses. Planet D sits, um, much further out

00:03:57 --> 00:03:59 from the star on a wide orbit, so it's cooler

00:03:59 --> 00:04:02 and dimmer than its siblings, hence the

00:04:02 --> 00:04:04 difficulty. And satisfyingly, its

00:04:04 --> 00:04:07 presence helps explain that odd structure in

00:04:07 --> 00:04:09 the debris disk that's puzzled astronomers

00:04:09 --> 00:04:10 for years.

00:04:10 --> 00:04:13 Avery: There's also a nice milestone tucked in here.

00:04:13 --> 00:04:15 This makes Beta Pictoris only the second

00:04:15 --> 00:04:18 planetary system after HR

00:04:18 --> 00:04:20 8799, where more than two

00:04:20 --> 00:04:23 planets have been directly. We're building

00:04:23 --> 00:04:26 up actual family portraits of other solar

00:04:26 --> 00:04:26 systems now.

00:04:27 --> 00:04:29 Anna: And an independent team at the University of

00:04:29 --> 00:04:32 California spotted the same object in their

00:04:32 --> 00:04:34 own data at almost the same time, which gives

00:04:34 --> 00:04:37 the detection real confidence. Now the

00:04:37 --> 00:04:40 bit our audience will love. Beta Pictoris is

00:04:40 --> 00:04:43 a southern star. It sits in the constellation

00:04:43 --> 00:04:46 Pictor, the Painter's Easel, just next to

00:04:46 --> 00:04:48 brilliant canopus. And at 63 light

00:04:48 --> 00:04:51 years away, it's visible from Australia and

00:04:51 --> 00:04:53 New Zealand. Though right now in July

00:04:53 --> 00:04:56 it's low in our evening sky and best hunted

00:04:56 --> 00:04:58 in the pre dawn hours later in

00:04:58 --> 00:05:01 Avery: the year, a planetary system with three

00:05:01 --> 00:05:03 photographed worlds sitting in our southern

00:05:03 --> 00:05:05 sky. Not bad at all.

00:05:05 --> 00:05:08 Next, A, uh, project nine years in the

00:05:08 --> 00:05:11 making has just crossed the finish line. The

00:05:11 --> 00:05:14 U.S. national Science Foundation's National

00:05:14 --> 00:05:17 Radio Astronomy Observatory has announced

00:05:17 --> 00:05:20 that observations for the Very Large Array

00:05:20 --> 00:05:22 Sky Survey VLAS are

00:05:22 --> 00:05:25 complete. It's the most detailed radio

00:05:25 --> 00:05:27 survey of the sky ever conducted.

00:05:28 --> 00:05:31 Anna: This is the VLA in New Mexico. The

00:05:31 --> 00:05:34 iconic Y shaped array of 27 dishes

00:05:34 --> 00:05:36 from every space documentary ever made.

00:05:36 --> 00:05:39 Avery: That's the one. From September 2017

00:05:39 --> 00:05:42 through February this year, the array

00:05:42 --> 00:05:45 repeatedly swept about 34

00:05:45 --> 00:05:48 square degrees. Essentially the whole sky

00:05:48 --> 00:05:51 visible from New Mexico and everything north

00:05:51 --> 00:05:53 of minus 40 degrees declination.

00:05:53 --> 00:05:56 That's roughly 80% of the entire

00:05:56 --> 00:05:59 celestial sphere. Mapped at a resolution

00:05:59 --> 00:06:02 of about 2 and a half arcseconds in the 2

00:06:02 --> 00:06:03 to 4 GHz band.

00:06:03 --> 00:06:05 Anna: And how does that compare to what came

00:06:05 --> 00:06:06 before?

00:06:06 --> 00:06:09 Avery: It's about 18 times sharper than the

00:06:09 --> 00:06:12 previous benchmark all sky radio survey from

00:06:12 --> 00:06:14 the 1990s. The numbers are

00:06:14 --> 00:06:16 staggering. Roughly six and a half thousand

00:06:17 --> 00:06:20 thousand observing hours. Half a petabyte of

00:06:20 --> 00:06:22 raw data. And the processed data products are

00:06:22 --> 00:06:25 expected to reach around 2 petabytes, the

00:06:25 --> 00:06:28 largest data volume the VLA has ever

00:06:28 --> 00:06:31 produced. They use a clever on the fly

00:06:31 --> 00:06:34 mosaicing technique where the antennas sweep

00:06:34 --> 00:06:36 continuously across the sky in a raster

00:06:36 --> 00:06:39 pattern rather than stopping to point at each

00:06:39 --> 00:06:39 field.

00:06:39 --> 00:06:42 Anna: And crucially, they surveyed the sky multiple

00:06:42 --> 00:06:45 times over those nine years. Which means VLAS

00:06:45 --> 00:06:48 isn't just a map, it's a movie. Comparing

00:06:48 --> 00:06:51 epochs revealed a dynamic radio sky.

00:06:51 --> 00:06:53 Sources that flare, fade or appear from

00:06:53 --> 00:06:56 nowhere. Exploding stars, feeding black

00:06:56 --> 00:06:58 holes, colliding neutron stars.

00:06:59 --> 00:07:01 Avery: Which brings us to the timing. And honestly,

00:07:01 --> 00:07:03 the timing is the best part of the story.

00:07:04 --> 00:07:07 Just over two weeks ago on June 30, the

00:07:07 --> 00:07:10 Vera C. Rubin Observatory in Chile began

00:07:10 --> 00:07:13 its decade long legacy survey of space and

00:07:13 --> 00:07:15 time, sweeping the southern optical sky

00:07:16 --> 00:07:18 every few nights. So for the first time in

00:07:18 --> 00:07:21 history, we have a complete high resolution

00:07:21 --> 00:07:24 radio map and a real time optical

00:07:24 --> 00:07:27 transient stream operating simultaneously.

00:07:27 --> 00:07:29 Anna: Though when Rubin flags something going bang

00:07:29 --> 00:07:32 in the optical, astronomers can immediately

00:07:32 --> 00:07:34 check what that patch of sky looks like and

00:07:34 --> 00:07:37 looked like in the radio. The whole multi

00:07:37 --> 00:07:39 wavelength discovery machine the community

00:07:39 --> 00:07:42 has spent two decades building is now

00:07:42 --> 00:07:44 switched on and the data's public.

00:07:44 --> 00:07:47 Avery: Radio astronomers, multi wavelength folks,

00:07:47 --> 00:07:50 citizen scientists. The radio sky now

00:07:50 --> 00:07:52 belongs to everyone.

00:07:52 --> 00:07:55 Anna: Now to a decades old mystery that may

00:07:55 --> 00:07:57 finally have its answer. Avery, how do

00:07:57 --> 00:08:00 supermassive black holes keep feeding?

00:08:00 --> 00:08:03 Nearly every large galaxy hosts one of these

00:08:03 --> 00:08:06 monsters. Millions or billions of times the

00:08:06 --> 00:08:09 mass of the Sun. When they feed, they blast

00:08:09 --> 00:08:11 out enormous energy, powerful jets that heat

00:08:11 --> 00:08:14 the gas around them. And that's the paradox.

00:08:14 --> 00:08:17 That heating should cut off the black hole's

00:08:17 --> 00:08:19 own fuel supply. So why don't they starve?

00:08:20 --> 00:08:23 Avery: The leading idea has been a kind of cosmic

00:08:23 --> 00:08:25 recycling loop. The heated gas eventually

00:08:25 --> 00:08:28 cools back down, condenses into long thin

00:08:28 --> 00:08:31 streamers called filaments and rains back

00:08:31 --> 00:08:33 towards the center. Self regulating

00:08:34 --> 00:08:36 but Actually seeing the connection filament

00:08:36 --> 00:08:39 to black hole has eluded astronomers for

00:08:39 --> 00:08:40 decades.

00:08:40 --> 00:08:43 Anna: Until now. An international team led by Julie

00:08:43 --> 00:08:46 Hvlasic Lorando at the University of Montreal

00:08:46 --> 00:08:48 pointed the James Webb Space telescope at

00:08:48 --> 00:08:51 NGC 4696, the giant

00:08:51 --> 00:08:53 elliptical galaxy at the heart of the

00:08:53 --> 00:08:56 Centaurus cluster, about 145

00:08:56 --> 00:08:58 million light years away. Their results were

00:08:58 --> 00:09:00 published this week in the Astrophysical

00:09:00 --> 00:09:01 Journal Letters.

00:09:01 --> 00:09:04 Avery: And Centaurus, we should note, is a southern

00:09:04 --> 00:09:07 constellation. This galaxy cluster rides high

00:09:07 --> 00:09:09 in our winter sky right now, though you'll

00:09:09 --> 00:09:11 need a decent telescope for the galaxy

00:09:11 --> 00:09:11 itself.

00:09:12 --> 00:09:14 Anna: White. Now, Hubble had previously

00:09:14 --> 00:09:17 photographed a curious S shaped swirl of gas

00:09:17 --> 00:09:19 near this galaxy's central black hole. But

00:09:19 --> 00:09:22 Hubble could only show where the gas sat, not

00:09:22 --> 00:09:24 how it moved. So the team gave Webb's

00:09:24 --> 00:09:27 NIRSP instrument nearly eight hours on the

00:09:27 --> 00:09:29 target and mapped the motion of the gas deep

00:09:29 --> 00:09:32 inside the black hole's sphere of influence,

00:09:32 --> 00:09:35 resolving features just 30 light years across

00:09:35 --> 00:09:37 in a galaxy hundreds of thousands of light

00:09:37 --> 00:09:38 years wide.

00:09:38 --> 00:09:40 Avery: And the swirl turned out to be

00:09:41 --> 00:09:44 Anna: a spinning disk of gas wrapped around

00:09:44 --> 00:09:46 the black hole, nearly 800 light

00:09:46 --> 00:09:49 years across, with material whipping around

00:09:49 --> 00:09:52 at, uh, up to 600 kilometers per second.

00:09:52 --> 00:09:55 And here's the money shot. That disk is

00:09:55 --> 00:09:58 physically connected to one of the huge

00:09:58 --> 00:10:00 infalling filaments stretching out into the

00:10:00 --> 00:10:03 galaxy. They watched gas flowing along

00:10:03 --> 00:10:06 the filament, pouring into the disk, and from

00:10:06 --> 00:10:08 the disk falling onto the black hole.

00:10:09 --> 00:10:12 Avery: The missing link caught on camera heat the

00:10:12 --> 00:10:14 gas. The gas cools into filaments. The

00:10:14 --> 00:10:16 filaments feed the disk. The disk feeds the

00:10:16 --> 00:10:18 black hole. The black hole heats the gas.

00:10:19 --> 00:10:20 Round and round it goes.

00:10:20 --> 00:10:22 Anna: Havlasic Lorando said Webb is revealing that

00:10:22 --> 00:10:25 black holes might be the ultimate cosmic

00:10:25 --> 00:10:27 recyclers. And because this feeding loop

00:10:27 --> 00:10:29 shapes when galaxies can and can't form

00:10:29 --> 00:10:32 stars, understanding it is really

00:10:32 --> 00:10:35 understanding how galaxies, including ours,

00:10:35 --> 00:10:35 grow up.

00:10:35 --> 00:10:38 Avery: Anna, uh, time for a double bill from the

00:10:38 --> 00:10:41 outer solar system. Two stories,

00:10:41 --> 00:10:43 one spacecraft, and a dwarf planet that

00:10:43 --> 00:10:46 keeps on giving. First,

00:10:46 --> 00:10:49 scientists have detected landslides on Pluto

00:10:49 --> 00:10:50 for the very first time.

00:10:50 --> 00:10:53 Anna: This is New Horizons data, isn't it? That

00:10:53 --> 00:10:55 Flyby was 11 years ago this week.

00:10:55 --> 00:10:58 Avery: It is, and that's the delightful part. A

00:10:58 --> 00:11:00 paper in the journal Icarus, which has been

00:11:00 --> 00:11:03 making headlines this week, reports that an

00:11:03 --> 00:11:05 international team went back through the high

00:11:05 --> 00:11:08 resolution images from New Horizons lorry

00:11:08 --> 00:11:10 camera pictures showing Pluto's surface at

00:11:10 --> 00:11:13 about 300 meters per pixel and found

00:11:13 --> 00:11:16 six large landslides inside three impact

00:11:16 --> 00:11:19 craters near Sputnik Planita. That famous

00:11:19 --> 00:11:20 heart shaped nitrogen ice plane.

00:11:21 --> 00:11:23 Anna: How do you recognize a landslide on a world

00:11:23 --> 00:11:24 made of ice?

00:11:25 --> 00:11:27 Avery: Same fingerprints as Earth. Crescent shaped

00:11:27 --> 00:11:30 collapse scars near the crater rims. Huge

00:11:30 --> 00:11:32 displaced blocks of ice and debris fanning

00:11:32 --> 00:11:35 out across the crater floors. The team

00:11:35 --> 00:11:37 measured them. These slides descend one and a

00:11:37 --> 00:11:40 half to over two kilometers, run out as far

00:11:40 --> 00:11:42 as 14 and a half kilometers and the largest

00:11:42 --> 00:11:45 covers around 130 square kilometers.

00:11:45 --> 00:11:48 Anna: And landslides are everywhere else, aren't

00:11:48 --> 00:11:50 they? Earth, Mars, Ceres,

00:11:50 --> 00:11:53 asteroids, even Pluto's moon Charon showed

00:11:53 --> 00:11:56 evidence years ago Pluto itself was the odd

00:11:56 --> 00:11:57 one out which was

00:11:57 --> 00:12:00 Avery: genuinely puzzling because Pluto has steep

00:12:00 --> 00:12:02 crater walls and rugged icy terrain. All the

00:12:02 --> 00:12:05 right ingredients. Now the gap is filled and

00:12:05 --> 00:12:08 it tells us gravity driven slope processes

00:12:08 --> 00:12:10 are actively reshaping Pluto's frozen

00:12:10 --> 00:12:13 surface. Even under gravity, a fraction of

00:12:13 --> 00:12:15 ours. What triggered them is still open.

00:12:15 --> 00:12:18 Possibilities range from tectonic activity to

00:12:18 --> 00:12:19 meteoroid impacts.

00:12:19 --> 00:12:22 Anna: A world we visited for a few hours in 2015,

00:12:23 --> 00:12:25 still handing us firsts a decade later.

00:12:26 --> 00:12:28 Avery: And um, it's not done because part two of

00:12:28 --> 00:12:30 our Pluto double is about

00:12:30 --> 00:12:32 Avery: the other half of that famous pair

00:12:32 --> 00:12:35 Anna: of Charon, Pluto's enormous moon. So

00:12:35 --> 00:12:38 big relative to Pluto that the two really

00:12:38 --> 00:12:40 form a double world. And a study published

00:12:41 --> 00:12:43 Tuesday in Nature Communications says

00:12:43 --> 00:12:46 Charon's mountains have preserved a memory of

00:12:46 --> 00:12:47 a wilder youth.

00:12:47 --> 00:12:48 Avery: What kind of memory?

00:12:49 --> 00:12:52 Anna: A record of despinning across the solar

00:12:52 --> 00:12:54 system. Tidal forces gradually slow a body's

00:12:54 --> 00:12:57 rotation and as ah, the spin slows the

00:12:57 --> 00:13:00 body's shape relaxes stressing and

00:13:00 --> 00:13:02 cracking the surface. The it's long been

00:13:02 --> 00:13:05 theorized for Charon but clear geological

00:13:05 --> 00:13:08 evidence was missing. So Han, Zeng Chin

00:13:08 --> 00:13:10 and colleagues at ETH Zurich and

00:13:10 --> 00:13:13 UCLA examined the orientations

00:13:13 --> 00:13:16 and types of tectonic features, mountain

00:13:16 --> 00:13:18 ranges and faults in Aus Terra

00:13:18 --> 00:13:21 Sharon's northern rugged highlands. Again

00:13:21 --> 00:13:23 using New Horizons flyby data.

00:13:24 --> 00:13:26 Avery: And um, the tectonic pattern fits the de

00:13:26 --> 00:13:27 spinning story beautifully.

00:13:28 --> 00:13:30 Anna: Their modeling suggests Charon's rotation

00:13:30 --> 00:13:33 period was once around 14.3 hours

00:13:33 --> 00:13:36 and it has since slowed to today's roughly

00:13:36 --> 00:13:39 153 hours locked in step with

00:13:39 --> 00:13:41 its orbit around Pluto. That's more than a

00:13:41 --> 00:13:44 tenfold slowdown and the stresses from that

00:13:44 --> 00:13:46 transformation are etched into the mountains

00:13:46 --> 00:13:48 we photographed in 2015.

00:13:48 --> 00:13:51 Avery: Chen said the study drastically changed her

00:13:51 --> 00:13:53 understanding of Charon's geologic history.

00:13:53 --> 00:13:55 And there's a bonus finding, isn't there

00:13:55 --> 00:13:57 about how Charon was born?

00:13:57 --> 00:14:00 Anna: Yes, the way despinning and global

00:14:00 --> 00:14:02 contraction evolved together favors

00:14:02 --> 00:14:05 what's called a cold start for Charon, which

00:14:05 --> 00:14:08 is a real clue to the early thermal history

00:14:08 --> 00:14:11 of icy moons across the Outer solar system.

00:14:11 --> 00:14:14 So between Pluto's landslides and charon's

00:14:14 --> 00:14:17 slowing spin, one 11 year old dataset

00:14:17 --> 00:14:19 gave us two papers in a week. Not a bad

00:14:19 --> 00:14:21 return on a flyby.

00:14:21 --> 00:14:23 Avery: Our final story today, Anna, uh, comes with

00:14:23 --> 00:14:26 some genuinely eye widening numbers.

00:14:26 --> 00:14:29 SpaceX has filed its latest semi annual

00:14:29 --> 00:14:32 constellation status report with the U.S.

00:14:32 --> 00:14:34 federal Communications Commission. And

00:14:34 --> 00:14:37 according to coverage of the filing, StarLink

00:14:37 --> 00:14:38 satellites performed

00:14:38 --> 00:14:42 207

00:14:42 --> 00:14:44 collision avoidance maneuvers between

00:14:44 --> 00:14:46 December 2025 and

00:14:46 --> 00:14:48 May 2026.

00:14:48 --> 00:14:51 Anna: 207 in six months,

00:14:51 --> 00:14:53 up nearly 60

00:14:53 --> 00:14:55 Avery: on the previous half year. Put the two

00:14:55 --> 00:14:58 periods together and the constellation made

00:14:58 --> 00:15:00 over 355

00:15:00 --> 00:15:03 dodges in 12 months. More

00:15:03 --> 00:15:05 than triple what it performed in all of

00:15:05 --> 00:15:08 2024. At uh, on average,

00:15:08 --> 00:15:11 each Starlink satellite now swerves more

00:15:11 --> 00:15:14 than 40 times a year. That's nearly a

00:15:14 --> 00:15:16 dodge a week per satellite.

00:15:16 --> 00:15:18 Anna: Let's be fair to SpaceX for a moment though.

00:15:19 --> 00:15:21 These maneuvers are the system working as

00:15:21 --> 00:15:22 designed, aren't they?

00:15:22 --> 00:15:24 Avery: They are. The satellites dodge

00:15:24 --> 00:15:27 autonomously whenever the predicted collision

00:15:27 --> 00:15:30 probability exceeds 3 in 10 million,

00:15:30 --> 00:15:33 an extremely conservative threshold, far

00:15:33 --> 00:15:36 tighter than the industry standard. Experts

00:15:36 --> 00:15:38 consistently credit SpaceX with managing its

00:15:38 --> 00:15:41 traffic well and being transparent with the

00:15:41 --> 00:15:44 data. The concern is the trendline,

00:15:44 --> 00:15:45 not the competence.

00:15:45 --> 00:15:47 Anna: Because the numbers compound. More

00:15:47 --> 00:15:50 satellites means more close approaches means

00:15:50 --> 00:15:53 more maneuvers means more residual risk

00:15:53 --> 00:15:55 that never quite goes to zero.

00:15:55 --> 00:15:58 Avery: Exactly the point Huw Lewis makes. He's the

00:15:58 --> 00:16:00 University of Birmingham um, astronautics

00:16:00 --> 00:16:02 professor who's tracked these reports for

00:16:02 --> 00:16:05 years. Each maneuver cuts the collision odds

00:16:05 --> 00:16:08 to about one in a million, which sounds

00:16:08 --> 00:16:11 negligible, but as he puts it, if you make

00:16:11 --> 00:16:13 a million maneuvers with a one in a million

00:16:13 --> 00:16:16 residual, you end up with an aggregate risk

00:16:16 --> 00:16:18 across the Constellation that you simply

00:16:18 --> 00:16:21 can't get rid of. His blunt assessment,

00:16:21 --> 00:16:23 he thinks we're heading towards a situation

00:16:23 --> 00:16:26 where there will be a collision involving an

00:16:26 --> 00:16:28 operational satellite in the Constellation.

00:16:29 --> 00:16:32 Avery: And the projections on current growth

00:16:32 --> 00:16:35 Starlink passes. A million total avoidance

00:16:35 --> 00:16:37 maneuvers by mid2027. And by

00:16:37 --> 00:16:40 2030 the constellation could be making more

00:16:40 --> 00:16:42 than a million maneuvers every single year.

00:16:43 --> 00:16:46 Remember too, and regular listeners will.

00:16:46 --> 00:16:49 SpaceX has applied to the FCC to grow

00:16:49 --> 00:16:51 Starlink toward 100 satellites,

00:16:51 --> 00:16:53 a story we covered a couple of weeks back.

00:16:54 --> 00:16:56 And it's not alone up there. Amazon's

00:16:56 --> 00:16:58 Constellation and China's Qian Fan are

00:16:58 --> 00:17:00 actively deploying as well.

00:17:00 --> 00:17:03 Anna: The number of operational spacecraft in orbit

00:17:03 --> 00:17:05 has gone from about 10 to about

00:17:05 --> 00:17:08 16 in just a year. Other

00:17:08 --> 00:17:10 experts are calling for operators to disclose

00:17:10 --> 00:17:12 predicted maneuver counts before

00:17:12 --> 00:17:15 Constellations are even approved. Though

00:17:15 --> 00:17:17 regulators know whether the satellites can

00:17:17 --> 00:17:19 Avery: actually keep up, low Earth orbit is a

00:17:19 --> 00:17:22 shared resource. And this is the traffic

00:17:22 --> 00:17:24 report. We'll keep watching the numbers

00:17:24 --> 00:17:27 because everyone from astronomers to airlines

00:17:27 --> 00:17:29 to your GPs depends on that neighborhood

00:17:29 --> 00:17:30 staying safe.

00:17:30 --> 00:17:33 Anna: Time now for tonight's skywatching. And for

00:17:33 --> 00:17:35 our Southern Hemisphere friends, the news is

00:17:35 --> 00:17:38 good. The Moon is a waning crescent rising in

00:17:38 --> 00:17:40 the small hours, so evenings this week are

00:17:40 --> 00:17:43 dark and glorious, which means

00:17:43 --> 00:17:46 Avery: the winter Milky Way at its absolute best

00:17:46 --> 00:17:48 face south after dinner. And the galactic

00:17:48 --> 00:17:51 core in Sagittarius and Scorpius is almost

00:17:51 --> 00:17:54 directly overhead from most of Australia and

00:17:54 --> 00:17:57 New Zealand dust lanes. Star clouds, the

00:17:57 --> 00:17:59 lot. If you can get away from city lights

00:17:59 --> 00:18:01 this week, do it while you're there.

00:18:01 --> 00:18:04 Anna: Sweep up Omega, uh, Centauri and the Southern

00:18:04 --> 00:18:06 Cross riding high. And if you've got

00:18:06 --> 00:18:08 binoculars, the star fields between

00:18:08 --> 00:18:11 Scorpius's tail and the teapot of Sagittarius

00:18:11 --> 00:18:14 will keep you busy all evening. Saturn

00:18:14 --> 00:18:16 is climbing in the east by mid evening for a

00:18:16 --> 00:18:18 late night treat. And dazzling Venus still

00:18:18 --> 00:18:21 rules the early evening western sky.

00:18:21 --> 00:18:24 Avery: And one for the launch watchers. SpaceX's

00:18:24 --> 00:18:27 Starship Flight 13 window opens tonight,

00:18:27 --> 00:18:29 US time. That's tomorrow morning for us

00:18:30 --> 00:18:32 from about 8:45 aesthetic.

00:18:33 --> 00:18:35 So pour a coffee and watch this space. We'll

00:18:35 --> 00:18:37 have the full story in Saturday's weekend

00:18:37 --> 00:18:38 wrap.

00:18:38 --> 00:18:40 Anna: That's it for today's episode. Thanks for

00:18:40 --> 00:18:43 joining us. You can find show notes, links to

00:18:43 --> 00:18:45 every story and our back catalog@ah,

00:18:46 --> 00:18:48 astronomydaily.IO and we're astronomy

00:18:48 --> 00:18:50 Daily Pod on all the socials.

00:18:51 --> 00:18:53 Avery: Astronomy Daily is part of the bytes.com

00:18:53 --> 00:18:55 podcast network. I'm um, Avery.

00:18:55 --> 00:18:58 Anna: And I'm Anna. We'll see you tomorrow. Until

00:18:58 --> 00:19:00 then, clear skies.