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00:00:00 --> 00:00:02 Anna: Hello, and welcome to Astronomy Daily,
00:00:03 --> 00:00:06 your daily dose of space news from across
00:00:06 --> 00:00:08 the cosmos. I'm Anna.
00:00:08 --> 00:00:11 Avery: And I'm, um, avery. It's Friday the 19th of
00:00:11 --> 00:00:13 June, 2026, and we have an
00:00:13 --> 00:00:15 absolutely packed show for you today.
00:00:16 --> 00:00:19 Anna: We're talking salty skies on a mysterious
00:00:19 --> 00:00:21 pink world, Black holes with serious
00:00:21 --> 00:00:24 indigestion, a new batch of spy
00:00:24 --> 00:00:27 satellites heading to orbit right now, and a
00:00:27 --> 00:00:29 lunar lander that could be the cornerstone of
00:00:29 --> 00:00:32 humanity's first first moon base.
00:00:32 --> 00:00:35 Avery: Plus, we'll find out what a NASA spacecraft
00:00:35 --> 00:00:37 learned from a double lobed asteroid that's
00:00:37 --> 00:00:40 been slowly reshaping itself for more than
00:00:40 --> 00:00:43 100 million years. And we'll celebrate
00:00:43 --> 00:00:45 a little robot that's just run a marathon
00:00:45 --> 00:00:46 on Mars.
00:00:47 --> 00:00:49 Anna: If you're watching on YouTubeMusic, smash
00:00:49 --> 00:00:51 that subscribe button. If you're listening.
00:00:51 --> 00:00:54 Wherever podcasts live, a review means the
00:00:54 --> 00:00:54 world to us.
00:00:55 --> 00:00:56 Let's get into the news.
00:00:56 --> 00:00:59 Avery: Our first story today is a gorgeous piece of
00:00:59 --> 00:01:01 science from the James Webb Space Telescope.
00:01:01 --> 00:01:03 And it involves a world that astronomers have
00:01:03 --> 00:01:06 been desperate to study for over a decade.
00:01:06 --> 00:01:09 Anna: GJ 504b, the
00:01:09 --> 00:01:12 pink planet. It was first discovered back in
00:01:12 --> 00:01:15 2013, and it got that nickname because of
00:01:15 --> 00:01:17 its distinctive, rosy, hazy appearance.
00:01:18 --> 00:01:20 It orbits a sun like star about
00:01:20 --> 00:01:22 57 light years from Earth.
00:01:22 --> 00:01:25 Avery: And here's what made it so tantalizing and so
00:01:25 --> 00:01:28 frustrating at the same time. It's one of the
00:01:28 --> 00:01:31 coldest planetary mass companions ever
00:01:31 --> 00:01:33 directly imaged, sitting at around
00:01:33 --> 00:01:36 550 degrees Fahrenheit. For
00:01:36 --> 00:01:38 context, that's roughly the temperature of a
00:01:38 --> 00:01:40 domestic bread oven, which sounds hot
00:01:40 --> 00:01:43 Anna: to us, but for directly imaged worlds,
00:01:43 --> 00:01:46 that's genuinely frigid. Most are, uh,
00:01:46 --> 00:01:48 between 1 and 2 degrees
00:01:48 --> 00:01:51 Fahrenheit. The pink planet was so cold and
00:01:51 --> 00:01:54 so faint that every attempt to study it from
00:01:54 --> 00:01:57 ground failed. Teams around the world tried
00:01:57 --> 00:01:58 and came
00:01:58 --> 00:02:00 Avery: up empty, which made it a perfect target for
00:02:00 --> 00:02:03 Webb and a team led by Anish Babuvaj
00:02:03 --> 00:02:05 at Northwestern University center for
00:02:05 --> 00:02:08 Interdisciplinary Exploration and Research
00:02:08 --> 00:02:10 and Astrophysics, Sierra
00:02:10 --> 00:02:12 finally cracked it open.
00:02:12 --> 00:02:15 Anna: The results were published yesterday in the
00:02:15 --> 00:02:17 Astronomical Journal, and they are wild.
00:02:17 --> 00:02:18 The atmosphere of
00:02:18 --> 00:02:21 GJ504B is filled
00:02:21 --> 00:02:24 with exotic chemistry, heavy elements
00:02:24 --> 00:02:27 including carbon, bio oxygen, nitrogen
00:02:27 --> 00:02:30 and sulfur. But the real headline, finding
00:02:30 --> 00:02:32 Salt Clouds.
00:02:32 --> 00:02:34 Avery: For the first time ever, astronomers have
00:02:34 --> 00:02:37 found direct evidence for salt clouds in a
00:02:37 --> 00:02:39 cold object's atmosphere. Scientists had
00:02:39 --> 00:02:42 theorized this was possible more than 15
00:02:42 --> 00:02:44 years ago, but nobody had actually seen it
00:02:44 --> 00:02:45 until now.
00:02:45 --> 00:02:48 Anna: Babu Raj and his team ran simulations
00:02:48 --> 00:02:51 testing three different types of clouds, and
00:02:51 --> 00:02:53 only the salt cloud model produced results
00:02:53 --> 00:02:56 that Were physically consistent with the Webb
00:02:56 --> 00:02:58 data when they accounted the salt clouds.
00:02:58 --> 00:03:01 Previously confusing molecular signatures in
00:03:01 --> 00:03:04 the spectrum suddenly made sense.
00:03:04 --> 00:03:06 Avery: There's also a twist about what this object
00:03:06 --> 00:03:09 actually is. With a mass of around
00:03:09 --> 00:03:12 25 times that of Jupiter, the pink planet
00:03:12 --> 00:03:14 might not technically be a planet after all.
00:03:14 --> 00:03:17 It may be a brown dwarf, a so called
00:03:17 --> 00:03:20 failed star, Something that formed like a
00:03:20 --> 00:03:23 star but never accumulated quite enough mass
00:03:23 --> 00:03:25 to ignite hydrogen fusion in its core.
00:03:26 --> 00:03:27 Anna: The team also found that
00:03:27 --> 00:03:30 GJ504B appears
00:03:30 --> 00:03:33 unusually rich in metals, elements
00:03:33 --> 00:03:35 heavier than hydrogen and helium, and is
00:03:35 --> 00:03:38 likely between 2.5 and 4 billion
00:03:38 --> 00:03:41 years old, which explains why it's cooled
00:03:41 --> 00:03:41 down so much.
00:03:42 --> 00:03:44 Avery: There are still open questions exactly what
00:03:44 --> 00:03:47 kinds of salts make up those clouds? Is it
00:03:47 --> 00:03:50 truly a planet or a brown dwarf? Both
00:03:50 --> 00:03:53 questions may require further web time to
00:03:53 --> 00:03:55 answer, but what a first look.
00:03:55 --> 00:03:58 Anna: Babu Raj put it beautifully. When we
00:03:58 --> 00:04:01 finally obtained its spectrum, it immediately
00:04:01 --> 00:04:03 looked interesting. But once we started
00:04:03 --> 00:04:06 digging deeper into the data, we realized it
00:04:06 --> 00:04:08 was not like anything we had analyzed before.
00:04:09 --> 00:04:12 Avery: The pink planet. Salty, ancient,
00:04:12 --> 00:04:15 mysterious, and finally starting to give up
00:04:15 --> 00:04:15 its secrets.
00:04:16 --> 00:04:18 Anna: Story 2 and we're staying in the world of
00:04:18 --> 00:04:21 exotic astrophysics. The this time with
00:04:21 --> 00:04:24 supermassive black holes, and specifically
00:04:24 --> 00:04:27 with what happens long after they've devoured
00:04:27 --> 00:04:28 an unfortunate star.
00:04:29 --> 00:04:31 Avery: So to set the scene, every so often a uh,
00:04:31 --> 00:04:34 star wanders too close to a supermassive
00:04:34 --> 00:04:37 black hole. The black hole's gravity shreds
00:04:37 --> 00:04:39 the star apart in a process called a tidal
00:04:39 --> 00:04:42 disruption event, or tde, producing
00:04:42 --> 00:04:45 a brilliant flash of optical, ultraviolet and
00:04:45 --> 00:04:47 X ray light from the center of what was
00:04:47 --> 00:04:49 previously a quiet galaxy.
00:04:49 --> 00:04:52 Anna: This initial flare fades over weeks to
00:04:52 --> 00:04:55 months, and historically that's when
00:04:55 --> 00:04:57 astronomers stopped watching the show seemed
00:04:57 --> 00:04:58 to be over.
00:04:59 --> 00:05:01 Avery: But it turns out the show was only just
00:05:01 --> 00:05:04 getting started. Using the NSF's Very Large
00:05:04 --> 00:05:07 Array radio observatory in New Mexico, One of
00:05:07 --> 00:05:09 the most sensitive radio observatories on the
00:05:09 --> 00:05:12 planet. A team led by Kate Alexander at the
00:05:12 --> 00:05:15 University of Arizona has discovered that a
00:05:15 --> 00:05:17 surprising number of these TDE's produce
00:05:17 --> 00:05:20 a powerful delayed radio burst months
00:05:20 --> 00:05:22 or even years later.
00:05:22 --> 00:05:24 Anna: Like a cosmic belch?
00:05:25 --> 00:05:27 Avery: Exactly like a cosmic belch,
00:05:27 --> 00:05:29 Alexander herself said at a press conference
00:05:29 --> 00:05:32 this week. Sometimes after it seems like they
00:05:32 --> 00:05:35 are done eating, they may get indigestion and
00:05:35 --> 00:05:37 let out a large radio burp. These late
00:05:37 --> 00:05:39 time radio burps can appear when the black
00:05:39 --> 00:05:42 hole eats too fast or eats too slowly,
00:05:42 --> 00:05:43 which I love
00:05:43 --> 00:05:46 Anna: because it turns out the universe has the
00:05:46 --> 00:05:48 same dietary advice as your GP.
00:05:49 --> 00:05:52 Avery: The team assembled the largest sample of TDEs
00:05:52 --> 00:05:54 ever studied at radio wavelengths, and they
00:05:54 --> 00:05:57 found that roughly 40% of all TDES
00:05:57 --> 00:05:59 eventually produced this delayed radio
00:05:59 --> 00:06:02 emission. That is a much higher rate than
00:06:02 --> 00:06:05 Anna: anyone expected, and crucially, they've
00:06:05 --> 00:06:07 worked out how to predict which ones will
00:06:07 --> 00:06:10 burp. TDEs that later produce
00:06:10 --> 00:06:13 delayed radio emission are less likely to
00:06:13 --> 00:06:15 show helium emission lines in their early
00:06:15 --> 00:06:18 optical spectra. That early chemical
00:06:18 --> 00:06:20 fingerprint is a signal to keep watching.
00:06:21 --> 00:06:23 Avery: This has real practical implications for
00:06:23 --> 00:06:26 telescope scheduling. Radio follow up of
00:06:26 --> 00:06:28 TDES was typically abandoned if nothing
00:06:28 --> 00:06:31 showed up in the first year. This research
00:06:31 --> 00:06:34 shows that's far too soon. These events are
00:06:34 --> 00:06:36 long, evolving stories, and the most
00:06:36 --> 00:06:39 energetic chapter may unfold years down the
00:06:39 --> 00:06:39 track.
00:06:39 --> 00:06:42 Anna: What we're seeing here is a window into how
00:06:42 --> 00:06:45 supermassive black holes grow, launch
00:06:45 --> 00:06:48 outflows, and reshape the galaxies around
00:06:48 --> 00:06:50 them. And the VLA is giving us a
00:06:50 --> 00:06:53 Avery: front row seat worth noting for our
00:06:53 --> 00:06:55 dedicated listeners. This is distinct from
00:06:55 --> 00:06:58 the Jetty McJetface story we've discussed
00:06:58 --> 00:07:01 before. This new VLA research covers a
00:07:01 --> 00:07:03 whole population of TDEs and establishes the
00:07:03 --> 00:07:06 general rules, a really significant step
00:07:06 --> 00:07:07 forward.
00:07:07 --> 00:07:10 Story three and this one is happening as you
00:07:10 --> 00:07:11 listen, literally right now.
00:07:12 --> 00:07:13 Anna: SpaceX launched
00:07:13 --> 00:07:16 NROL179 from
00:07:16 --> 00:07:19 Vandenberg Space Force Base in California in
00:07:19 --> 00:07:21 the early hours of this morning, Friday the
00:07:21 --> 00:07:24 19th of June. That's mission number 14
00:07:24 --> 00:07:26 in the National Reconnaissance Office's
00:07:26 --> 00:07:29 rapidly expanding proliferated
00:07:29 --> 00:07:30 Architecture program.
00:07:30 --> 00:07:33 Avery: And for those not across this program, it's
00:07:33 --> 00:07:35 worth stepping back to appreciate the scale
00:07:35 --> 00:07:38 of what the NRO and SpaceX are doing
00:07:38 --> 00:07:41 together. The Proliferated Architecture is
00:07:41 --> 00:07:43 a new approach to reconnaissance from space.
00:07:43 --> 00:07:45 Rather than a small number of large,
00:07:45 --> 00:07:48 expensive satellites, the NRO is deploying
00:07:48 --> 00:07:51 a constellation of many smaller satellites
00:07:51 --> 00:07:53 that are faster to build, cheaper to replace,
00:07:53 --> 00:07:56 and far more resilient to stay ahead
00:07:56 --> 00:07:56 of
00:07:56 --> 00:07:59 Anna: the competition and ensure it can continue to
00:07:59 --> 00:08:01 operate in a heightened threat environment.
00:08:01 --> 00:08:04 That's the official framing from the nro. The
00:08:04 --> 00:08:07 agency is modernizing its architecture in
00:08:07 --> 00:08:09 space and on the ground, delivering more
00:08:09 --> 00:08:12 capability faster with increased resilience.
00:08:13 --> 00:08:15 Avery: NRO L179 is the
00:08:15 --> 00:08:18 71st Falcon 9 launch of
00:08:18 --> 00:08:21 2026 since 71 launches,
00:08:21 --> 00:08:23 and the year isn't half over. That is a pace
00:08:23 --> 00:08:26 that was simply inconceivable a decade ago.
00:08:26 --> 00:08:29 Anna: Of the 70 launches so far this year,
00:08:29 --> 00:08:32 57 have been devoted to SpaceX's
00:08:32 --> 00:08:34 Starlink broadband constellation,
00:08:35 --> 00:08:37 demonstrating just how much of the company's
00:08:37 --> 00:08:40 cadence is now driven by its own satellite
00:08:40 --> 00:08:40 business.
00:08:41 --> 00:08:43 Avery: SpaceX livestreamed the launch up until
00:08:43 --> 00:08:45 shortly after liftoff, but then ended
00:08:45 --> 00:08:48 coverage at the ONRO's request the number of
00:08:48 --> 00:08:51 satellites deployed and the details of their
00:08:51 --> 00:08:54 or remain classified standard
00:08:54 --> 00:08:55 operating procedure for this program.
00:08:56 --> 00:08:58 Anna: What we do know is that this network has now
00:08:58 --> 00:09:01 grown to become, in the NRO's own words,
00:09:01 --> 00:09:03 the largest and most capable government
00:09:03 --> 00:09:06 constellation in orbit in US history.
00:09:07 --> 00:09:08 A remarkable statement.
00:09:09 --> 00:09:12 Story four and we're heading to the moon. Or
00:09:12 --> 00:09:13 at least to the Pittsburgh company that's
00:09:13 --> 00:09:15 building the spacecraft that's going to the
00:09:15 --> 00:09:16 moon.
00:09:16 --> 00:09:19 Avery: On Monday, June 15, Astrobotic
00:09:19 --> 00:09:22 held a public unveiling of its Griffin 1
00:09:22 --> 00:09:24 lunar lander at its head headquarters in
00:09:24 --> 00:09:27 Pittsburgh, Pennsylvania. And this isn't just
00:09:27 --> 00:09:29 another moon mission. NASA has formally
00:09:29 --> 00:09:32 designated Griffin 1 as Moon Base
00:09:32 --> 00:09:35 2, the second mission in its planned program
00:09:35 --> 00:09:38 to establish a permanent human presence on
00:09:38 --> 00:09:39 the lunar surface.
00:09:39 --> 00:09:42 Anna: Griffin one is what Astrobotic CEO
00:09:42 --> 00:09:45 John Thornton called the first infrastructure
00:09:45 --> 00:09:47 class lander going to the surface of the
00:09:47 --> 00:09:49 moon. That's a meaningful distinction.
00:09:50 --> 00:09:52 Previous commercial landers, including
00:09:52 --> 00:09:54 Astrobotics own Peregrine, which launched in
00:09:54 --> 00:09:57 January 2024 but suffered a
00:09:57 --> 00:09:59 propulsion failure and couldn't attempt a
00:09:59 --> 00:10:02 landing, were relatively small payload
00:10:02 --> 00:10:02 delivery vehicles.
00:10:03 --> 00:10:06 Avery: Griffin one is in a different class. It has
00:10:06 --> 00:10:07 a payload capacity of
00:10:07 --> 00:10:10 660kg. It will
00:10:10 --> 00:10:13 carry 10 payloads from six nations to the
00:10:13 --> 00:10:16 lunar South Pole region, specifically the
00:10:16 --> 00:10:18 Noble Crater area near Mons Mouton.
00:10:19 --> 00:10:22 Anna: The headline payload is Astrolabe's Flip
00:10:22 --> 00:10:24 rover, the Flex Lunar innovation
00:10:24 --> 00:10:27 platform. At 500kg, it will
00:10:27 --> 00:10:30 be the heaviest commercial payload ever
00:10:30 --> 00:10:32 delivered to the lunar surface. It's carrying
00:10:32 --> 00:10:35 four NASA science instruments and will help
00:10:35 --> 00:10:38 demonstrate the mobility systems that future
00:10:38 --> 00:10:39 lunar terrain vehicles will need.
00:10:40 --> 00:10:42 Avery: Other payloads come from esa, Canada,
00:10:43 --> 00:10:46 Germany, Japan and Australia, which is
00:10:46 --> 00:10:47 always nice to call out for our audience here
00:10:47 --> 00:10:49 in the Southern Hemisphere.
00:10:49 --> 00:10:51 Anna: The lander is currently completing final
00:10:51 --> 00:10:54 integration at Astrobotics Pittsburgh
00:10:54 --> 00:10:57 facility before being shipped to NASA's Jet
00:10:57 --> 00:10:59 Propulsion Laboratory in California for
00:10:59 --> 00:11:01 environmental testing. After that, it heads
00:11:01 --> 00:11:03 to Cap Canaveral for launch preparations,
00:11:04 --> 00:11:06 with the Flip rover joining it there.
00:11:06 --> 00:11:09 Avery: Launch is targeted for the fourth quarter of
00:11:09 --> 00:11:12 2026 with a SpaceX Falcon Heavy.
00:11:12 --> 00:11:14 So we may be watching this one land before
00:11:14 --> 00:11:15 the year's out.
00:11:16 --> 00:11:18 Anna: This mission comes in the wake of Voyager
00:11:18 --> 00:11:21 Technology's acquisition of Astrobotic in a
00:11:21 --> 00:11:24 deal valued at up to $300 million.
00:11:24 --> 00:11:26 So the company arrives at this milestone
00:11:26 --> 00:11:29 moment with new resources and a new parent.
00:11:29 --> 00:11:32 Thornton summed it up. This lander will
00:11:32 --> 00:11:34 be part of the cornerstone of building the
00:11:34 --> 00:11:37 moon base on the surface of the moon from a
00:11:37 --> 00:11:39 Avery: company that started nearly two decades ago
00:11:39 --> 00:11:41 and, um, has had its share of heartbreak.
00:11:42 --> 00:11:44 Here's hoping Griffin sticks The Landing
00:11:45 --> 00:11:45 Story
00:11:45 --> 00:11:48 Anna: 5, and this is one of my favorites.
00:11:48 --> 00:11:51 Today, an asteroid with an extraordinarily
00:11:51 --> 00:11:54 rich life story, now told in remarkable
00:11:54 --> 00:11:56 detail. Thanks to NASA's Lucy spacecraft.
00:11:57 --> 00:11:59 Avery: Lucy is on its way to study the Trojan
00:11:59 --> 00:12:02 asteroids, the ancient rocky bodies that
00:12:02 --> 00:12:04 shared Jupiter's orbit and are considered
00:12:04 --> 00:12:06 time capsules from the early solar system.
00:12:06 --> 00:12:09 But on April 20 last year, it made a
00:12:09 --> 00:12:12 practice flyby of a small main belt
00:12:12 --> 00:12:14 asteroid called 52246.
00:12:15 --> 00:12:17 Anna: Donald Johansen, named after the
00:12:17 --> 00:12:20 paleoanthropologist who discovered Lucy, the
00:12:20 --> 00:12:23 famous hominin fossil, which is a lovely bit
00:12:23 --> 00:12:24 of naming symmetry.
00:12:24 --> 00:12:27 Avery: The flyby was brief, just a close pass
00:12:27 --> 00:12:30 at 960km, but it was
00:12:30 --> 00:12:32 extraordinarily productive. And the results
00:12:33 --> 00:12:35 published yesterday in the journal Science
00:12:35 --> 00:12:38 reconstructed a 155 million
00:12:38 --> 00:12:40 year biography of this little world.
00:12:41 --> 00:12:43 Anna: The first thing you notice from the Lucy
00:12:43 --> 00:12:46 images is Donald Johansen is a
00:12:46 --> 00:12:49 contact binary. Two distinct
00:12:49 --> 00:12:51 lobes of rock fused together at a
00:12:51 --> 00:12:54 narrow neck, like a, ah, cosmic
00:12:54 --> 00:12:57 snowman. If snowmen were made of ancient
00:12:57 --> 00:12:58 asteroid rubble.
00:12:58 --> 00:13:01 Avery: The team led by Simone Markey at the
00:13:01 --> 00:13:03 Southwest Research Institute mapped craters
00:13:03 --> 00:13:06 across both lobes and found them saturated.
00:13:06 --> 00:13:08 So old that new craters are simply
00:13:08 --> 00:13:11 obliterating older ones. Based on impact
00:13:11 --> 00:13:14 statistics for the main asteroid belt, the
00:13:14 --> 00:13:16 surface is at least 40 million years old.
00:13:16 --> 00:13:19 Anna: That's consistent with Donald Johansen
00:13:19 --> 00:13:22 being a member of the Origin asteroid
00:13:22 --> 00:13:25 family. A, ah, collection of fragments from a
00:13:25 --> 00:13:27 parent body that was catastrophically
00:13:27 --> 00:13:30 destroyed around 155
00:13:30 --> 00:13:33 million years ago. The two lobes are
00:13:33 --> 00:13:36 likely pieces of that original smash up
00:13:36 --> 00:13:39 that eventually found each other and merged.
00:13:39 --> 00:13:41 Avery: But here's where it gets genuinely
00:13:41 --> 00:13:44 fascinating. The neck connecting the two
00:13:44 --> 00:13:46 lobes is younger than the lobes themselves,
00:13:46 --> 00:13:49 smoother, with far fewer craters,
00:13:49 --> 00:13:51 estimated as less than 20 million years old.
00:13:52 --> 00:13:54 So how do you get an old body with a young
00:13:54 --> 00:13:55 neck?
00:13:55 --> 00:13:58 Anna: The answer lies in the asteroid's
00:13:58 --> 00:14:01 rotation. Lucy confirmed that Donald
00:14:01 --> 00:14:03 Johanson rotates extraordinarily
00:14:03 --> 00:14:05 slowly once every
00:14:05 --> 00:14:08 252.6
00:14:08 --> 00:14:11 hours. That's more than 10 Earth days
00:14:11 --> 00:14:14 per rotation. And it's tumbling as
00:14:14 --> 00:14:16 well, with a second wobbling period of
00:14:16 --> 00:14:19 455 hours.
00:14:19 --> 00:14:22 Avery: This ultra slow spin is the key to
00:14:22 --> 00:14:25 everything. When contact binaries first form,
00:14:25 --> 00:14:27 they're typically spinning fast. Centrifugal
00:14:27 --> 00:14:30 force counteracts gravity and pushes material
00:14:30 --> 00:14:33 out towards the ends. But over millions of
00:14:33 --> 00:14:36 years, pressure from sunlight, a subtle
00:14:36 --> 00:14:38 but relentless force called the YORP effect,
00:14:39 --> 00:14:40 gradually slows the rotation
00:14:41 --> 00:14:44 Anna: once the spin rate drops below a critical
00:14:44 --> 00:14:47 threshold, somewhere around once every
00:14:47 --> 00:14:49 10 hours. For Donald Johansson,
00:14:49 --> 00:14:52 gravity takes over from centrifugal force
00:14:52 --> 00:14:55 and suddenly loose material on the smaller
00:14:55 --> 00:14:58 lobe starts sliding toward the larger one,
00:14:58 --> 00:15:00 like sand flowing down a hill.
00:15:01 --> 00:15:04 Avery: Every new impact rattles the asteroid. More
00:15:04 --> 00:15:06 landslides, more regolith flowing towards the
00:15:06 --> 00:15:09 center. The net gets built up over time,
00:15:09 --> 00:15:12 layer by layer, smoothed by millions of
00:15:12 --> 00:15:14 slow motion avalanches. That's why it's
00:15:14 --> 00:15:15 younger than the rest of the body.
00:15:16 --> 00:15:19 Anna: What I love about this story is that it shows
00:15:19 --> 00:15:22 what a brief flyby can actually reveal
00:15:22 --> 00:15:24 when you have the right instruments and the
00:15:24 --> 00:15:27 right analysis. The Lucy team measured
00:15:27 --> 00:15:30 this asteroid for a matter of hours and
00:15:30 --> 00:15:32 pieced together a geological narrative
00:15:32 --> 00:15:35 spanning over a hundred million years.
00:15:36 --> 00:15:38 Avery: And this was the practice run. In August
00:15:38 --> 00:15:41 2027, Lucy will fly past Eurybates,
00:15:41 --> 00:15:44 a Trojan asteroid more than 10 times the
00:15:44 --> 00:15:47 size of Donald Johansson. If we learned this
00:15:47 --> 00:15:49 much from a quick pass at a small main belt
00:15:49 --> 00:15:52 rock, the Trojan, uh, encounters are going to
00:15:52 --> 00:15:53 be extraordinary.
00:15:54 --> 00:15:57 Anna: The solar system's history, one flyby
00:15:57 --> 00:15:57 at a time.
00:15:58 --> 00:16:00 Avery: And our final story today is one that
00:16:00 --> 00:16:02 deserves a moment of genuine celebration.
00:16:03 --> 00:16:05 Anna: NASA's Perseverance rover has now
00:16:05 --> 00:16:08 driven more than 26.2
00:16:08 --> 00:16:11 miles across the surface of Mars.
00:16:11 --> 00:16:13 In other words, it has completed a
00:16:13 --> 00:16:16 marathon on another planet.
00:16:16 --> 00:16:19 Avery: Percy, as the team affectionately calls it,
00:16:19 --> 00:16:22 landed in Jezero crater on 18th February
00:16:22 --> 00:16:25 2021. It has been trundling across the mart
00:16:25 --> 00:16:28 landscape ever since, drilling rocks,
00:16:28 --> 00:16:30 collecting samples, taking panoramic images,
00:16:30 --> 00:16:33 and doing science that would have seemed like
00:16:33 --> 00:16:34 science fiction not long ago.
00:16:35 --> 00:16:37 Anna: 26.2 miles, or
00:16:37 --> 00:16:40 42.2 kilometers in just
00:16:40 --> 00:16:43 over five years. That sounds slow.
00:16:43 --> 00:16:46 And compared to a human marathon runner, it
00:16:46 --> 00:16:49 obviously is. But remember that for
00:16:49 --> 00:16:52 Percy, driving is the interruption between
00:16:52 --> 00:16:55 science. The rover's days are filled with
00:16:55 --> 00:16:57 drilling, abrading rock, surfing surfaces,
00:16:58 --> 00:17:00 calibrating instruments, and studying ancient
00:17:00 --> 00:17:01 geology.
00:17:02 --> 00:17:04 Avery: And, um, the terrain it's traversing now,
00:17:04 --> 00:17:06 beyond the western rim of Jezero Crater,
00:17:07 --> 00:17:09 is some of the most scientifically valuable
00:17:09 --> 00:17:12 ground of the entire mission. Ancient
00:17:12 --> 00:17:14 fractured rocks, igneous minerals that
00:17:14 --> 00:17:17 predate the formation of Jezero itself.
00:17:17 --> 00:17:19 Geological structures that may preserve
00:17:19 --> 00:17:21 evidence of Mars earliest history.
00:17:22 --> 00:17:24 Anna: Perseverance is also approaching the distance
00:17:24 --> 00:17:27 record for any rover on another planet. The
00:17:27 --> 00:17:29 record currently belongs to NASA, NASA's
00:17:29 --> 00:17:31 Opportunity rover, which managed
00:17:31 --> 00:17:34 45.16 kilometers over
00:17:34 --> 00:17:37 roughly 14 years before a global
00:17:37 --> 00:17:39 dust storm ended its mission in 2018.
00:17:40 --> 00:17:42 Percy is closing in on that record, with the
00:17:42 --> 00:17:44 mission planned to continue through at least
00:17:44 --> 00:17:46 2028.
00:17:46 --> 00:17:48 Avery: To put that in perspective, if you were
00:17:48 --> 00:17:50 standing on the Martian surface watching
00:17:50 --> 00:17:53 Perseverance go by, you'd be experiencing
00:17:53 --> 00:17:56 temperatures that could drop to minus 8, 80
00:17:56 --> 00:17:59 degrees Celsius. Overnight, breathing nothing
00:17:59 --> 00:18:01 at all and being bombarded by radiation.
00:18:02 --> 00:18:04 The fact that this rover not only survives
00:18:04 --> 00:18:07 but thrives in that environment and keeps
00:18:07 --> 00:18:09 doing world class science is a genuine
00:18:09 --> 00:18:10 engineering marvel.
00:18:11 --> 00:18:13 Anna: Mars One Soul at a Time
00:18:13 --> 00:18:16 Congratulations to the entire Perseverance
00:18:16 --> 00:18:17 team on this milestone.
00:18:18 --> 00:18:20 Avery: And that wraps up today's edition of
00:18:20 --> 00:18:23 Astronomy Daily. Your Friday fix of the
00:18:23 --> 00:18:25 best space and astronomy news from across the
00:18:25 --> 00:18:26 cosmos.
00:18:26 --> 00:18:29 Anna: A beautiful lineup today. Salty alien
00:18:29 --> 00:18:32 skies belching black holes, a
00:18:32 --> 00:18:35 landmark moon lander, the remarkable story of
00:18:35 --> 00:18:37 an asteroid that's been renovating itself for
00:18:37 --> 00:18:40 millions of years, and a little rover hitting
00:18:40 --> 00:18:42 a major milestone on the Red planet.
00:18:42 --> 00:18:45 Avery: If you enjoyed today's show, please take 30
00:18:45 --> 00:18:47 seconds to leave us a review. Wherever you
00:18:47 --> 00:18:49 listen, it makes a genuine difference in
00:18:49 --> 00:18:51 helping new listeners find us.
00:18:51 --> 00:18:53 Anna: You can follow us on social media at
00:18:53 --> 00:18:56 AstroDaily Pod, visit our website at
00:18:56 --> 00:18:59 astronomydailyio for show notes and
00:18:59 --> 00:19:01 transcripts. And if you're watching on
00:19:01 --> 00:19:03 YouTubeMusic, subscribe and hit the bell so
00:19:03 --> 00:19:04 you never miss an episode.
00:19:05 --> 00:19:07 Avery: From all of us here at Astronomy Daily and
00:19:07 --> 00:19:10 the bytes.com podcast network, have a
00:19:10 --> 00:19:12 wonderful weekend. Keep looking up and we'll
00:19:12 --> 00:19:14 see you back here on tomorrow with our
00:19:14 --> 00:19:15 weekend wrap.
00:19:15 --> 00:19:16 Anna: Clear skies, everyone.