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 Welcome to Astronomy Daily, your daily
00:00:02 --> 00:00:05 dose of space and astronomy news. I'm
00:00:05 --> 00:00:06 Anna.
00:00:06 --> 00:00:09 >> And I'm Avery. It's Thursday, the 16th
00:00:09 --> 00:00:12 of July, 2026, and we have a genuinely
00:00:12 --> 00:00:15 lovely lineup for you today, including a
00:00:15 --> 00:00:17 story that's been 10 years in the
00:00:17 --> 00:00:19 making. Or more accurately, 10 years in
00:00:19 --> 00:00:20 the hiding.
00:00:20 --> 00:00:23 >> That's our lead. Astronomers have
00:00:23 --> 00:00:24 finally caught a planet that's been
00:00:24 --> 00:00:26 playing hideand seek with them for over
00:00:26 --> 00:00:29 a decade. And it turns out to be the
00:00:29 --> 00:00:31 faintest exoplanet ever imaged from
00:00:31 --> 00:00:33 Earth. And it lives in a southern
00:00:34 --> 00:00:36 constellation, which makes it feel just
00:00:36 --> 00:00:37 a little bit like ours.
00:00:37 --> 00:00:39 >> We've also got the completion of a
00:00:39 --> 00:00:42 9-year project to build the sharpest
00:00:42 --> 00:00:44 radio map of the entire sky and the
00:00:44 --> 00:00:47 James Web Space Telescope catching a
00:00:47 --> 00:00:49 super massive black hole in the act of
00:00:49 --> 00:00:52 feeding itself. Ben, it's a double bill
00:00:52 --> 00:00:54 from the outer solar system. Landslides
00:00:54 --> 00:00:57 on Pluto spotted for the first time and
00:00:57 --> 00:01:00 evidence that Pluto's big moon Cheron
00:01:00 --> 00:01:03 once spun more than 10 times faster than
00:01:03 --> 00:01:04 it does today.
00:01:04 --> 00:01:06 >> And we'll wrap the news with some
00:01:06 --> 00:01:09 sobering numbers. SpaceX's Starlink
00:01:09 --> 00:01:10 satellites had to dodge potential
00:01:10 --> 00:01:14 collisions more than 355
00:01:14 --> 00:01:16 times in the past year. We'll unpack
00:01:16 --> 00:01:19 what that means for everyone's orbit.
00:01:19 --> 00:01:21 plus your southern hemisphere sky
00:01:21 --> 00:01:23 watching for tonight. Let's get into it.
00:01:23 --> 00:01:27 Avery, cast your mind back. In 2008,
00:01:27 --> 00:01:29 astronomers directly imaged a planet
00:01:29 --> 00:01:32 around the young star Beta Ptorus, one
00:01:32 --> 00:01:34 of the very first exoplanets ever
00:01:34 --> 00:01:37 photographed. That was Beta Pictorius B.
00:01:38 --> 00:01:40 A second planet C followed and ever
00:01:40 --> 00:01:43 since there's been a nagging suspicion
00:01:43 --> 00:01:45 that the system was hiding something
00:01:45 --> 00:01:45 more
00:01:45 --> 00:01:48 >> because of the disc, right? Beta Pctorus
00:01:48 --> 00:01:50 has this magnificent debris disc. It's
00:01:50 --> 00:01:52 the poster child for planet formation.
00:01:52 --> 00:01:54 And parts of it were warped and sculpted
00:01:54 --> 00:01:57 in ways that two known planets couldn't
00:01:57 --> 00:01:58 fully explain.
00:01:58 --> 00:02:01 >> Exactly. And now we know why. In a study
00:02:01 --> 00:02:03 published Wednesday in the Astrophysical
00:02:03 --> 00:02:05 Journal Letters, a team using the
00:02:05 --> 00:02:08 European Southern Observatory's Very
00:02:08 --> 00:02:11 Large Telescope in Chile has confirmed a
00:02:11 --> 00:02:14 third planet, Beta Pictorius D. And
00:02:14 --> 00:02:16 here's the headline stat. It's roughly
00:02:16 --> 00:02:20 100 times fainter than Beta Pictorius B,
00:02:20 --> 00:02:22 which makes it the faintest exoplanet
00:02:22 --> 00:02:25 ever directly imaged from Earth. 100
00:02:25 --> 00:02:28 times fainter. To put that in context
00:02:28 --> 00:02:30 for everyone, direct imaging means
00:02:30 --> 00:02:32 actually capturing the planet's own
00:02:32 --> 00:02:34 light in a photograph next to a star
00:02:34 --> 00:02:36 that's overwhelmingly brighter. It's
00:02:36 --> 00:02:39 often compared to spotting a firefly
00:02:39 --> 00:02:42 next to a lighthouse. This is spotting a
00:02:42 --> 00:02:45 very dim firefly. And the discovery
00:02:45 --> 00:02:48 itself was serendipitous. Ben Sutliff at
00:02:48 --> 00:02:51 the University of Edinburgh, who co-led
00:02:51 --> 00:02:53 the study, said they were originally
00:02:53 --> 00:02:55 just going back to study the known
00:02:55 --> 00:02:57 planet Beta Pictorius B to see how it
00:02:57 --> 00:03:00 changed over time. But in their new
00:03:00 --> 00:03:03 images from the VLT's AIS instrument,
00:03:03 --> 00:03:05 there was something else, a faint point
00:03:05 --> 00:03:07 of light separated from planet B that
00:03:07 --> 00:03:10 sent them down an entirely new path.
00:03:10 --> 00:03:12 >> And this is where the hideand seek comes
00:03:12 --> 00:03:14 in. Once they knew what to look for,
00:03:14 --> 00:03:17 they trled back through the archives and
00:03:17 --> 00:03:19 there it was, lurking in more than a
00:03:19 --> 00:03:21 decade of old observations from the VT
00:03:22 --> 00:03:23 sphere instrument. And even in James
00:03:24 --> 00:03:26 Webb's space telescope data, the planet
00:03:26 --> 00:03:29 had been photographed for years. Nobody
00:03:29 --> 00:03:30 had noticed.
00:03:30 --> 00:03:33 >> Co-author Jane Burkeby at Oxford put it
00:03:33 --> 00:03:35 beautifully. Planet D has been playing
00:03:35 --> 00:03:38 hideand seek with us for over a decade.
00:03:38 --> 00:03:41 And now we can say, "Found you." So,
00:03:41 --> 00:03:43 what do we know about the world itself?
00:03:43 --> 00:03:46 >> It's a gas giant about 2.4 times the
00:03:46 --> 00:03:49 mass of Jupiter, which sounds big, but
00:03:49 --> 00:03:50 is actually the lightweight of the
00:03:50 --> 00:03:53 family. Planets B and C are each 10
00:03:53 --> 00:03:56 Jupiter masses. Planet D sits much
00:03:56 --> 00:03:58 further out from the star on a wide
00:03:58 --> 00:04:00 orbit, so it's cooler and dimmer than
00:04:00 --> 00:04:03 its siblings, hence the difficulty. And
00:04:03 --> 00:04:05 satisfyingly, its presence helps explain
00:04:06 --> 00:04:08 that odd structure in the debris disc
00:04:08 --> 00:04:10 that's puzzled astronomers for years.
00:04:10 --> 00:04:13 >> There's also a nice milestone tucked in
00:04:13 --> 00:04:15 here. This makes Beta Ptorus only the
00:04:15 --> 00:04:19 second planetary system after HR8799
00:04:19 --> 00:04:21 where more than two planets have been
00:04:21 --> 00:04:24 directly imaged. We're building up
00:04:24 --> 00:04:26 actual family portraits of other solar
00:04:26 --> 00:04:27 systems. now
00:04:27 --> 00:04:29 >> and an independent team at the
00:04:29 --> 00:04:31 University of California spotted the
00:04:31 --> 00:04:33 same object in her own data at almost
00:04:33 --> 00:04:35 the same time which gives the detection
00:04:35 --> 00:04:38 real confidence. Now the bit our
00:04:38 --> 00:04:40 audience will love Beta Ptorus is a
00:04:40 --> 00:04:42 southern star. It sits in the
00:04:42 --> 00:04:45 constellation Pictor the painters easel
00:04:45 --> 00:04:48 just next to Brilliant Canopus and at 63
00:04:48 --> 00:04:50 lighty years away it's visible from
00:04:50 --> 00:04:52 Australia and New Zealand. Though right
00:04:52 --> 00:04:55 now in July, it's low in our evening sky
00:04:56 --> 00:04:57 and best hunted in the pre-dawn hours
00:04:58 --> 00:04:59 later in the year.
00:04:59 --> 00:05:01 >> A planetary system with three
00:05:01 --> 00:05:03 photographed worlds sitting in our
00:05:03 --> 00:05:06 southern sky. Not bad at all. Next, a n
00:05:06 --> 00:05:09 a project 9 years in the making has just
00:05:09 --> 00:05:12 crossed the finish line. The US National
00:05:12 --> 00:05:14 Science Foundation's National Radio
00:05:14 --> 00:05:17 Astronomy Observatory has announced that
00:05:17 --> 00:05:20 observations for the Very Large Array
00:05:20 --> 00:05:24 Sky Survey, VLAS, are complete. It's the
00:05:24 --> 00:05:27 most detailed radio survey of the sky
00:05:27 --> 00:05:28 ever conducted.
00:05:28 --> 00:05:31 >> This is the VA in New Mexico, the iconic
00:05:31 --> 00:05:34 Y-shaped array of 27 dishes from every
00:05:34 --> 00:05:37 space documentary ever made.
00:05:37 --> 00:05:40 >> That's the one. From September 2017
00:05:40 --> 00:05:42 through February this year, the array
00:05:42 --> 00:05:45 repeatedly swept about 34 square
00:05:46 --> 00:05:48 degrees. Essentially, the whole sky
00:05:48 --> 00:05:50 visible from New Mexico. Everything
00:05:50 --> 00:05:54 north of -40° declination. That's
00:05:54 --> 00:05:57 roughly 80% of the entire celestial
00:05:57 --> 00:06:00 sphere mapped at a resolution of about 2
00:06:00 --> 00:06:04 1/2 arcseconds in the 2 to 4 GHz band.
00:06:04 --> 00:06:05 >> And how does that compare to what came
00:06:05 --> 00:06:09 before? It's about 18 times sharper than
00:06:09 --> 00:06:11 the previous benchmark all sky radio
00:06:11 --> 00:06:14 survey from the 1990s. The numbers are
00:06:14 --> 00:06:18 staggering, roughly 6 1/2 observing
00:06:18 --> 00:06:21 hours, half a pabyte of raw data, and
00:06:21 --> 00:06:23 the processed data products are expected
00:06:23 --> 00:06:26 to reach around 2 pabytes, the largest
00:06:26 --> 00:06:29 data volume the VA has ever produced.
00:06:29 --> 00:06:32 They use a clever on the-fly mosaicing
00:06:32 --> 00:06:34 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
00:06:39 --> 00:06:40 each field.
00:06:40 --> 00:06:42 >> And crucially, they surveyed the sky
00:06:42 --> 00:06:44 multiple times over those nine years,
00:06:44 --> 00:06:47 which means Vlass isn't just a map, it's
00:06:47 --> 00:06:49 a movie. Comparing epochs revealed a
00:06:49 --> 00:06:52 dynamic radio sky sources that flare,
00:06:52 --> 00:06:55 fade, or appear from nowhere. exploding
00:06:55 --> 00:06:58 stars, feeding black holes, colliding
00:06:58 --> 00:06:59 neutron stars.
00:06:59 --> 00:07:01 >> Which brings us to the timing. And
00:07:01 --> 00:07:03 honestly, the timing is the best part of
00:07:03 --> 00:07:06 the story. Just over 2 weeks ago, on
00:07:06 --> 00:07:09 June 30th, the Vera C. Rubin Observatory
00:07:09 --> 00:07:12 in Chile began its decadel long legacy
00:07:12 --> 00:07:14 survey of space and time, sweeping the
00:07:14 --> 00:07:17 southern optical sky every few nights.
00:07:17 --> 00:07:19 So for the first time in history, we
00:07:20 --> 00:07:22 have a complete highresolution radio map
00:07:22 --> 00:07:25 and a real-time optical transient stream
00:07:25 --> 00:07:27 operating simultaneously.
00:07:27 --> 00:07:29 >> Though when Reuben flags something going
00:07:29 --> 00:07:31 bang in the optical, astronomers can
00:07:31 --> 00:07:33 immediately check what that patch of sky
00:07:33 --> 00:07:36 looks like and looked like in the radio.
00:07:36 --> 00:07:38 The whole multi-wavelength discovery
00:07:38 --> 00:07:40 machine the community has spent two
00:07:40 --> 00:07:43 decades building is now switched on
00:07:43 --> 00:07:45 >> and the data is public. Radio
00:07:45 --> 00:07:47 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 >> Now to a decades old mystery that may
00:07:55 --> 00:07:58 finally have its answer, Avery. How do
00:07:58 --> 00:08:00 super massive black holes keep feeding?
00:08:00 --> 00:08:03 Nearly every large galaxy hosts one of
00:08:03 --> 00:08:05 these monsters. Millions or billions of
00:08:05 --> 00:08:07 times the mass of the sun. When they
00:08:07 --> 00:08:10 feed, they blast out enormous energy,
00:08:10 --> 00:08:12 powerful jets that heat the gas around
00:08:12 --> 00:08:15 them. And that's the paradox. That
00:08:15 --> 00:08:17 heating should cut off the black hole's
00:08:17 --> 00:08:19 own fuel supply. So why don't they
00:08:19 --> 00:08:20 starve?
00:08:20 --> 00:08:22 >> The leading idea has been a kind of
00:08:22 --> 00:08:25 cosmic recycling loop. The heated gas
00:08:25 --> 00:08:27 eventually cools back down, condenses
00:08:27 --> 00:08:29 into long, thin streamers called
00:08:29 --> 00:08:32 filaments and rains back towards the
00:08:32 --> 00:08:35 center, self-regulating. But actually
00:08:35 --> 00:08:37 seeing the connection filament to black
00:08:37 --> 00:08:40 hole has eluded astronomers for decades
00:08:40 --> 00:08:43 >> until now. An international team led by
00:08:43 --> 00:08:45 Julia Havlassa Laurando at the
00:08:45 --> 00:08:47 University of Montreal pointed the James
00:08:47 --> 00:08:51 Webb Space Telescope at NGC 4696,
00:08:51 --> 00:08:53 the giant elliptical galaxy at the heart
00:08:53 --> 00:08:56 of the Centurus cluster about 145
00:08:56 --> 00:08:58 million lighty years away. Their results
00:08:58 --> 00:09:00 were published this week in the
00:09:00 --> 00:09:02 astrophysical journal Letters.
00:09:02 --> 00:09:04 >> And Centurus, we should note, is a
00:09:04 --> 00:09:06 southern constellation. This galaxy
00:09:06 --> 00:09:08 cluster rides high in our winter sky
00:09:08 --> 00:09:10 right now, though you'll need a decent
00:09:10 --> 00:09:12 telescope for the galaxy itself.
00:09:12 --> 00:09:14 >> Right. Now, Hubble had previously
00:09:14 --> 00:09:17 photographed a curious S-shaped swirl of
00:09:17 --> 00:09:19 gas near this galaxy's central black
00:09:19 --> 00:09:20 hole. But Hubble could only show where
00:09:20 --> 00:09:23 the gas sat, not how it moved. So the
00:09:23 --> 00:09:26 team gave Web's NISP instrument nearly 8
00:09:26 --> 00:09:28 hours on the target and mapped the
00:09:28 --> 00:09:30 motion of the gas deep inside the black
00:09:30 --> 00:09:33 hole sphere of influence, resolving
00:09:33 --> 00:09:35 features just 30 light years across in a
00:09:35 --> 00:09:37 galaxy hundreds of thousands of
00:09:37 --> 00:09:40 light-years wide. And the swirl turned
00:09:40 --> 00:09:41 out to be
00:09:41 --> 00:09:44 >> a spinning disc of gas wrapped around
00:09:44 --> 00:09:47 the black hole nearly 800 lightyears
00:09:47 --> 00:09:50 across with material whipping around at
00:09:50 --> 00:09:53 up to 600 km per second. And here's the
00:09:53 --> 00:09:56 money shot. That disc is physically
00:09:56 --> 00:09:58 connected to one of the huge infalling
00:09:58 --> 00:10:00 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 disc and
00:10:06 --> 00:10:08 from the disc falling onto the black
00:10:08 --> 00:10:09 hole.
00:10:09 --> 00:10:12 >> The missing link caught on camera. Heat
00:10:12 --> 00:10:14 the gas. The gas cools into filaments.
00:10:14 --> 00:10:16 The filaments feed the disc. The disc
00:10:16 --> 00:10:18 feeds the black hole. The black hole
00:10:18 --> 00:10:20 heats the gas. Round and round it goes.
00:10:20 --> 00:10:23 >> Pavlocondo said web is revealing that
00:10:23 --> 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
00:10:30 --> 00:10:32 stars, understanding it is really
00:10:32 --> 00:10:34 understanding how galaxies, including
00:10:34 --> 00:10:35 ours, grow up.
00:10:36 --> 00:10:38 >> Anna, time for a double bill from the
00:10:38 --> 00:10:41 outer solar system. Two stories, one
00:10:41 --> 00:10:44 spacecraft, and a dwarf planet that
00:10:44 --> 00:10:47 keeps on giving. First, scientists have
00:10:47 --> 00:10:49 detected landslides on Pluto for the
00:10:49 --> 00:10:51 very first time.
00:10:51 --> 00:10:53 >> This is New Horizon's data, isn't it?
00:10:53 --> 00:10:56 That flyby was 11 years ago this week.
00:10:56 --> 00:10:58 >> It is. And that's the delightful part. A
00:10:58 --> 00:11:00 paper in the journal Icorus, which has
00:11:00 --> 00:11:02 been making headlines this week, reports
00:11:02 --> 00:11:04 that an international team went back
00:11:04 --> 00:11:06 through the highresolution images from
00:11:06 --> 00:11:09 New Horizon's Lori camera. Pictures
00:11:09 --> 00:11:11 showing Pluto's surface at about 300 m
00:11:11 --> 00:11:15 per pixel and found six large landslides
00:11:15 --> 00:11:17 inside three impact craters near Sputnik
00:11:17 --> 00:11:19 Planita, that famous heart-shaped
00:11:19 --> 00:11:22 nitrogen ice plane. How do you recognize
00:11:22 --> 00:11:25 a landslide on a world made of ice?
00:11:25 --> 00:11:26 >> Same fingerprints as Earth.
00:11:26 --> 00:11:28 Crescent-shaped collapse scars near the
00:11:28 --> 00:11:31 crater rims, huge displaced blocks of
00:11:31 --> 00:11:33 ice, and debris fanning out across the
00:11:33 --> 00:11:35 crater floors. The team measured them.
00:11:35 --> 00:11:39 These slides descend 1 12 to over 2 km
00:11:39 --> 00:11:42 run out as far as 14 1/2 km, and the
00:11:42 --> 00:11:46 largest covers around the 130 km.
00:11:46 --> 00:11:47 >> And landslides are everywhere else,
00:11:47 --> 00:11:50 aren't they? Earth, Mars, series,
00:11:50 --> 00:11:53 asteroids. Even Pluto's moon, Sharon,
00:11:53 --> 00:11:55 showed evidence years ago. Pluto itself
00:11:55 --> 00:11:57 was the odd one out,
00:11:57 --> 00:11:59 >> which was genuinely puzzling because
00:11:59 --> 00:12:01 Pluto has steep crater walls and rugged
00:12:01 --> 00:12:04 icy terrain. All the right ingredients.
00:12:04 --> 00:12:06 Now, the gap is filled, and it tells us
00:12:06 --> 00:12:08 gravity-driven slope processes are
00:12:08 --> 00:12:10 actively reshaping Pluto's frozen
00:12:10 --> 00:12:13 surface, even under gravity a fraction
00:12:13 --> 00:12:15 of ours. What triggered them is still
00:12:15 --> 00:12:17 open. Possibilities range from tectonic
00:12:17 --> 00:12:19 activity to meteoroid impacts.
00:12:20 --> 00:12:22 >> A world we visited for a few hours in
00:12:22 --> 00:12:25 2015 still handing us firsts a decade
00:12:25 --> 00:12:26 later.
00:12:26 --> 00:12:29 >> And it's not done because part two of
00:12:29 --> 00:12:31 our Pluto double is about the other half
00:12:31 --> 00:12:33 of that famous pair.
00:12:33 --> 00:12:36 >> Jiren Pluto's enormous moon so big
00:12:36 --> 00:12:38 relative to Pluto that the two really
00:12:38 --> 00:12:40 form a double world. And a study
00:12:40 --> 00:12:42 published Tuesday in Nature
00:12:42 --> 00:12:44 Communications says Sharon's mountains
00:12:44 --> 00:12:47 have preserved a memory of a wilder
00:12:47 --> 00:12:47 youth.
00:12:47 --> 00:12:49 >> What kind of memory?
00:12:49 --> 00:12:52 >> A record of despinning across the solar
00:12:52 --> 00:12:54 system. Tidal forces gradually slow a
00:12:54 --> 00:12:57 body's rotation. And as the spin slows,
00:12:57 --> 00:13:00 the body's shape relaxes, stressing and
00:13:00 --> 00:13:02 cracking the surface. It's long been
00:13:02 --> 00:13:05 theorized for Sharon, but clear
00:13:05 --> 00:13:07 geological evidence was missing. So
00:13:07 --> 00:13:10 Hanzang Chin and colleagues at ETH Zoric
00:13:10 --> 00:13:13 and UCLA examined the orientations and
00:13:13 --> 00:13:16 types of tectonic features, mountain
00:13:16 --> 00:13:19 ranges and faults in Oz Terra, Sharon's
00:13:19 --> 00:13:22 northern rugged highlands. Again, using
00:13:22 --> 00:13:24 New Horizon's flyby data,
00:13:24 --> 00:13:26 >> and the tectonic pattern fits the
00:13:26 --> 00:13:27 despinning story
00:13:27 --> 00:13:29 >> beautifully. Their modeling suggests
00:13:29 --> 00:13:32 Sharon's rotation period was once around
00:13:32 --> 00:13:35 14.3 hours and it has since slowed to
00:13:35 --> 00:13:38 today's roughly 153 hours, locked in
00:13:38 --> 00:13:41 step with its orbit around Pluto. That's
00:13:41 --> 00:13:43 more than a 10-fold slowdown, and the
00:13:43 --> 00:13:45 stresses from that transformation are
00:13:45 --> 00:13:47 etched into the mountains we
00:13:47 --> 00:13:48 photographed in 2015.
00:13:48 --> 00:13:51 >> Chen said the study drastically changed
00:13:51 --> 00:13:53 her understanding of Cheron's geological
00:13:53 --> 00:13:55 history. And there's a bonus finding,
00:13:55 --> 00:13:57 isn't there, about how Cheron was born.
00:13:57 --> 00:14:00 Yes, the way despinning and global
00:14:00 --> 00:14:03 contraction evolved together favors
00:14:03 --> 00:14:05 what's called a cold start for Sharon,
00:14:05 --> 00:14:07 which is a real clue to the early
00:14:07 --> 00:14:10 thermal history of icy moons across the
00:14:10 --> 00:14:12 outer solar system. So, between Pluto's
00:14:12 --> 00:14:15 landslides and Sharon's slowing spin,
00:14:15 --> 00:14:18 one 11-year-old data set gave us two
00:14:18 --> 00:14:20 papers in a week. Not a bad return on a
00:14:20 --> 00:14:21 flyby.
00:14:21 --> 00:14:23 >> Our final story today, Anna, comes with
00:14:23 --> 00:14:26 some genuinely eyewidening numbers.
00:14:26 --> 00:14:29 SpaceX has filed its latest semiannual
00:14:29 --> 00:14:32 constellation status report with the US
00:14:32 --> 00:14:34 Federal Communications Commission. And
00:14:34 --> 00:14:36 according to coverage of the filing,
00:14:36 --> 00:14:42 Starling satellites performed 27
00:14:42 --> 00:14:44 collision avoidance maneuvers between
00:14:44 --> 00:14:48 December 2025 and May 2026.
00:14:48 --> 00:14:50 >> 207
00:14:50 --> 00:14:51 in 6 months.
00:14:52 --> 00:14:54 >> Up nearly 60 on the previous half
00:14:54 --> 00:14:57 year. Put the two periods together and
00:14:57 --> 00:15:01 the constellation made over 355
00:15:01 --> 00:15:04 dodges in 12 months, more than triple
00:15:04 --> 00:15:07 what it performed in all of 2024. At on
00:15:07 --> 00:15:10 average, each Starling satellite now
00:15:10 --> 00:15:13 swerves more than 40 times a year.
00:15:13 --> 00:15:15 That's nearly a dodge a week per
00:15:15 --> 00:15:16 satellite.
00:15:16 --> 00:15:18 >> Let's be fair to SpaceX for a moment,
00:15:18 --> 00:15:20 though. These maneuvers are the system
00:15:20 --> 00:15:22 working as designed, aren't they?
00:15:22 --> 00:15:24 >> They are. The satellites dodge
00:15:24 --> 00:15:27 autonomously whenever the predicted
00:15:27 --> 00:15:29 collision probability exceeds 3 in 10
00:15:30 --> 00:15:32 million, an extremely conservative
00:15:32 --> 00:15:34 threshold, far tighter than the industry
00:15:34 --> 00:15:37 standard. Experts consistently credit
00:15:37 --> 00:15:40 SpaceX with managing its traffic well
00:15:40 --> 00:15:42 and being transparent with the data. The
00:15:42 --> 00:15:44 concern is the trend line, not the
00:15:44 --> 00:15:46 competence. because the numbers
00:15:46 --> 00:15:49 compound. More satellites means more
00:15:49 --> 00:15:51 close approaches means more maneuvers
00:15:51 --> 00:15:54 means more residual risk that never
00:15:54 --> 00:15:55 quite goes to zero.
00:15:55 --> 00:15:58 >> Exactly the point Hugh Lewis makes. He's
00:15:58 --> 00:15:59 the University of Birmingham
00:15:59 --> 00:16:01 astronautics professor who's tracked
00:16:02 --> 00:16:04 these reports for years. Each maneuver
00:16:04 --> 00:16:07 cuts the collision odds to about 1 in a
00:16:07 --> 00:16:09 million, which sounds negligible, but as
00:16:09 --> 00:16:11 he puts it, if you make a million
00:16:11 --> 00:16:13 maneuvers with a 1 in a million
00:16:13 --> 00:16:16 residual, you end up with an aggregate
00:16:16 --> 00:16:18 risk across the constellation that you
00:16:18 --> 00:16:20 simply can't get rid of. His blunt
00:16:20 --> 00:16:22 assessment, he thinks we're heading
00:16:22 --> 00:16:24 towards a situation where there will be
00:16:24 --> 00:16:27 a collision involving an operational
00:16:27 --> 00:16:29 satellite in the constellation. And the
00:16:29 --> 00:16:31 projections
00:16:31 --> 00:16:33 >> on current growth, Starlink passes a
00:16:33 --> 00:16:36 million total avoidance maneuvers by mid
00:16:36 --> 00:16:39 2027. And by 2030, the constellation
00:16:39 --> 00:16:41 could be making more than a million
00:16:41 --> 00:16:44 maneuvers every single year. Remember
00:16:44 --> 00:16:47 too, and regular listeners will, SpaceX
00:16:47 --> 00:16:49 has applied to the FCC to grow Starlink
00:16:49 --> 00:16:52 toward a 100 satellites, a story we
00:16:52 --> 00:16:54 covered a couple of weeks back. And it's
00:16:54 --> 00:16:56 not alone up there. Amazon's
00:16:56 --> 00:16:59 constellation and China's Ken Fan are
00:16:59 --> 00:17:00 actively deploying as well.
00:17:00 --> 00:17:03 >> The number of operational spacecraft in
00:17:03 --> 00:17:05 orbit has gone from about 10 to
00:17:05 --> 00:17:08 about 16 in just a year. Other
00:17:08 --> 00:17:10 experts are calling for operators to
00:17:10 --> 00:17:12 disclose predicted maneuver counts
00:17:12 --> 00:17:15 before constellations are even approved.
00:17:15 --> 00:17:16 Though regulators know whether the
00:17:16 --> 00:17:18 satellites can actually keep up.
00:17:18 --> 00:17:21 >> Low Earth orbit is a shared resource.
00:17:21 --> 00:17:23 And this is the traffic report. We'll
00:17:23 --> 00:17:24 keep watching the numbers because
00:17:24 --> 00:17:27 everyone from astronomers to airlines to
00:17:27 --> 00:17:29 your GPS depends on that neighborhood
00:17:29 --> 00:17:31 staying safe.
00:17:31 --> 00:17:33 >> Time now for tonight's sky watching. And
00:17:33 --> 00:17:35 for our southern hemisphere friends, the
00:17:35 --> 00:17:37 news is good. The moon is a waning
00:17:37 --> 00:17:39 crescent rising in the small hours. So
00:17:40 --> 00:17:41 evenings this week are dark and
00:17:41 --> 00:17:42 glorious.
00:17:42 --> 00:17:45 >> Which means the winter Milky Way at its
00:17:45 --> 00:17:47 absolute best. Face south after dinner
00:17:48 --> 00:17:50 and the galactic core in Sagittarius and
00:17:50 --> 00:17:52 Scorpius is almost directly overhead
00:17:52 --> 00:17:55 from most of Australia and New Zealand.
00:17:55 --> 00:17:58 Dust lanes, star clouds, the lot. If you
00:17:58 --> 00:18:00 can get away from city lights this week,
00:18:00 --> 00:18:01 do it.
00:18:01 --> 00:18:03 >> While you're there, sweep up Omega
00:18:03 --> 00:18:05 Centauri and the Southern Cross riding
00:18:05 --> 00:18:07 high. And if you've got binoculars, the
00:18:07 --> 00:18:09 starfields between Scorpius's tail and
00:18:09 --> 00:18:12 the teapot of Sagittarius will keep you
00:18:12 --> 00:18:14 busy all evening. Saturn is climbing in
00:18:14 --> 00:18:16 the east by mid evening for a late night
00:18:16 --> 00:18:19 treat. And dazzling Venus still rules
00:18:19 --> 00:18:21 the early evening western sky.
00:18:21 --> 00:18:23 >> And one for the launch watchers.
00:18:23 --> 00:18:26 SpaceX's Starship Flight 13 window opens
00:18:26 --> 00:18:29 tonight, US time. That's tomorrow
00:18:29 --> 00:18:33 morning for us from about 8:45 AEST. So
00:18:33 --> 00:18:35 pour a coffee and watch this space.
00:18:35 --> 00:18:37 We'll have the full story in Saturday's
00:18:37 --> 00:18:38 weekend rap.
00:18:38 --> 00:18:40 >> That's it for today's episode. Thanks
00:18:40 --> 00:18:42 for joining us. You can find show notes,
00:18:42 --> 00:18:44 links to every story, and our back
00:18:44 --> 00:18:47 catalog at astronomydaily.io.
00:18:47 --> 00:18:50 And we're astronomyaily pod on all the
00:18:50 --> 00:18:51 socials.
00:18:51 --> 00:18:53 >> Astronomy Daily is part of the byes.com
00:18:54 --> 00:18:56 podcast network. I'm Avery
00:18:56 --> 00:18:58 >> and I'm Anna. We'll see you tomorrow.
00:18:58 --> 00:18:59 Until then,
00:18:59 --> 00:19:11 >> clear skies.
00:19:11 --> 00:19:15 Stories told.