Salty Skies on a Pink Planet, Black Holes Burp, and a Lunar Lander for Moon Base 2

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Anna: Hello, and welcome to Astronomy Daily,

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your daily dose of space news from across

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the cosmos. I'm Anna.

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Avery: And I'm, um, avery. It's Friday the 19th of

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June, 2026, and we have an

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absolutely packed show for you today.

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Anna: We're talking salty skies on a mysterious

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pink world, Black holes with serious

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indigestion, a new batch of spy

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satellites heading to orbit right now, and a

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lunar lander that could be the cornerstone of

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humanity's first first moon base.

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Avery: Plus, we'll find out what a NASA spacecraft

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learned from a double lobed asteroid that's

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been slowly reshaping itself for more than

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100 million years. And we'll celebrate

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a little robot that's just run a marathon

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on Mars.

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Anna: If you're watching on YouTubeMusic, smash

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that subscribe button. If you're listening.

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Wherever podcasts live, a review means the

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world to us.

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Let's get into the news.

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Avery: Our first story today is a gorgeous piece of

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science from the James Webb Space Telescope.

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And it involves a world that astronomers have

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been desperate to study for over a decade.

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Anna: GJ 504b, the

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pink planet. It was first discovered back in

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2013, and it got that nickname because of

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its distinctive, rosy, hazy appearance.

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It orbits a sun like star about

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57 light years from Earth.

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Avery: And here's what made it so tantalizing and so

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frustrating at the same time. It's one of the

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coldest planetary mass companions ever

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directly imaged, sitting at around

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550 degrees Fahrenheit. For

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context, that's roughly the temperature of a

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domestic bread oven, which sounds hot

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Anna: to us, but for directly imaged worlds,

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that's genuinely frigid. Most are, uh,

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between 1,000 and 2,000 degrees

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Fahrenheit. The pink planet was so cold and

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so faint that every attempt to study it from

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ground failed. Teams around the world tried

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and came

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Avery: up empty, which made it a perfect target for

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Webb and a team led by Anish Babuvaj

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at Northwestern University center for

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Interdisciplinary Exploration and Research

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and Astrophysics, Sierra

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finally cracked it open.

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Anna: The results were published yesterday in the

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Astronomical Journal, and they are wild.

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The atmosphere of

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GJ504B is filled

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with exotic chemistry, heavy elements

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including carbon, bio oxygen, nitrogen

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and sulfur. But the real headline, finding

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Salt Clouds.

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Avery: For the first time ever, astronomers have

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found direct evidence for salt clouds in a

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cold object's atmosphere. Scientists had

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theorized this was possible more than 15

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years ago, but nobody had actually seen it

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until now.

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Anna: Babu Raj and his team ran simulations

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testing three different types of clouds, and

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only the salt cloud model produced results

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that Were physically consistent with the Webb

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data when they accounted the salt clouds.

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Previously confusing molecular signatures in

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the spectrum suddenly made sense.

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Avery: There's also a twist about what this object

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actually is. With a mass of around

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25 times that of Jupiter, the pink planet

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might not technically be a planet after all.

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It may be a brown dwarf, a so called

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failed star, Something that formed like a

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star but never accumulated quite enough mass

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to ignite hydrogen fusion in its core.

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Anna: The team also found that

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GJ504B appears

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unusually rich in metals, elements

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heavier than hydrogen and helium, and is

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likely between 2.5 and 4 billion

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years old, which explains why it's cooled

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down so much.

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Avery: There are still open questions exactly what

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kinds of salts make up those clouds? Is it

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truly a planet or a brown dwarf? Both

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questions may require further web time to

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answer, but what a first look.

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Anna: Babu Raj put it beautifully. When we

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finally obtained its spectrum, it immediately

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looked interesting. But once we started

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digging deeper into the data, we realized it

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was not like anything we had analyzed before.

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Avery: The pink planet. Salty, ancient,

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mysterious, and finally starting to give up

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its secrets.

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Anna: Story 2 and we're staying in the world of

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exotic astrophysics. The this time with

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supermassive black holes, and specifically

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with what happens long after they've devoured

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an unfortunate star.

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Avery: So to set the scene, every so often a uh,

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star wanders too close to a supermassive

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black hole. The black hole's gravity shreds

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the star apart in a process called a tidal

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disruption event, or tde, producing

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a brilliant flash of optical, ultraviolet and

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X ray light from the center of what was

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previously a quiet galaxy.

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Anna: This initial flare fades over weeks to

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months, and historically that's when

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astronomers stopped watching the show seemed

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to be over.

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Avery: But it turns out the show was only just

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getting started. Using the NSF's Very Large

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Array radio observatory in New Mexico, One of

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the most sensitive radio observatories on the

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planet. A team led by Kate Alexander at the

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University of Arizona has discovered that a

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surprising number of these TDE's produce

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a powerful delayed radio burst months

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or even years later.

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Anna: Like a cosmic belch?

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Avery: Exactly like a cosmic belch,

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Alexander herself said at a press conference

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this week. Sometimes after it seems like they

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are done eating, they may get indigestion and

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let out a large radio burp. These late

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time radio burps can appear when the black

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hole eats too fast or eats too slowly,

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which I love

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Anna: because it turns out the universe has the

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same dietary advice as your GP.

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Avery: The team assembled the largest sample of TDEs

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ever studied at radio wavelengths, and they

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found that roughly 40% of all TDES

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eventually produced this delayed radio

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emission. That is a much higher rate than

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Anna: anyone expected, and crucially, they've

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worked out how to predict which ones will

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burp. TDEs that later produce

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delayed radio emission are less likely to

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show helium emission lines in their early

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optical spectra. That early chemical

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fingerprint is a signal to keep watching.

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Avery: This has real practical implications for

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telescope scheduling. Radio follow up of

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TDES was typically abandoned if nothing

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showed up in the first year. This research

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shows that's far too soon. These events are

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long, evolving stories, and the most

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energetic chapter may unfold years down the

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track.

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Anna: What we're seeing here is a window into how

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supermassive black holes grow, launch

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outflows, and reshape the galaxies around

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them. And the VLA is giving us a

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Avery: front row seat worth noting for our

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dedicated listeners. This is distinct from

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the Jetty McJetface story we've discussed

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before. This new VLA research covers a

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whole population of TDEs and establishes the

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general rules, a really significant step

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forward.

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Story three and this one is happening as you

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listen, literally right now.

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Anna: SpaceX launched

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NROL179 from

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Vandenberg Space Force Base in California in

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the early hours of this morning, Friday the

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19th of June. That's mission number 14

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in the National Reconnaissance Office's

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rapidly expanding proliferated

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Architecture program.

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Avery: And for those not across this program, it's

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worth stepping back to appreciate the scale

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of what the NRO and SpaceX are doing

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together. The Proliferated Architecture is

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a new approach to reconnaissance from space.

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Rather than a small number of large,

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expensive satellites, the NRO is deploying

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a constellation of many smaller satellites

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that are faster to build, cheaper to replace,

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and far more resilient to stay ahead

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of

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Anna: the competition and ensure it can continue to

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operate in a heightened threat environment.

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That's the official framing from the nro. The

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agency is modernizing its architecture in

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space and on the ground, delivering more

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capability faster with increased resilience.

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Avery: NRO L179 is the

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71st Falcon 9 launch of

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2026 since 71 launches,

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and the year isn't half over. That is a pace

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that was simply inconceivable a decade ago.

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Anna: Of the 70 launches so far this year,

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57 have been devoted to SpaceX's

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Starlink broadband constellation,

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demonstrating just how much of the company's

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cadence is now driven by its own satellite

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business.

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Avery: SpaceX livestreamed the launch up until

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shortly after liftoff, but then ended

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coverage at the ONRO's request the number of

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satellites deployed and the details of their

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or remain classified standard

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operating procedure for this program.

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Anna: What we do know is that this network has now

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grown to become, in the NRO's own words,

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the largest and most capable government

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constellation in orbit in US history.

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A remarkable statement.

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Story four and we're heading to the moon. Or

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at least to the Pittsburgh company that's

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building the spacecraft that's going to the

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moon.

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Avery: On Monday, June 15, Astrobotic

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held a public unveiling of its Griffin 1

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lunar lander at its head headquarters in

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Pittsburgh, Pennsylvania. And this isn't just

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another moon mission. NASA has formally

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designated Griffin 1 as Moon Base

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2, the second mission in its planned program

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to establish a permanent human presence on

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the lunar surface.

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Anna: Griffin one is what Astrobotic CEO

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John Thornton called the first infrastructure

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class lander going to the surface of the

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moon. That's a meaningful distinction.

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Previous commercial landers, including

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Astrobotics own Peregrine, which launched in

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January 2024 but suffered a

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propulsion failure and couldn't attempt a

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landing, were relatively small payload

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delivery vehicles.

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Avery: Griffin one is in a different class. It has

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a payload capacity of

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660kg. It will

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carry 10 payloads from six nations to the

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lunar South Pole region, specifically the

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Noble Crater area near Mons Mouton.

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Anna: The headline payload is Astrolabe's Flip

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rover, the Flex Lunar innovation

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platform. At 500kg, it will

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be the heaviest commercial payload ever

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delivered to the lunar surface. It's carrying

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four NASA science instruments and will help

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demonstrate the mobility systems that future

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lunar terrain vehicles will need.

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Avery: Other payloads come from esa, Canada,

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Germany, Japan and Australia, which is

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always nice to call out for our audience here

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in the Southern Hemisphere.

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Anna: The lander is currently completing final

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integration at Astrobotics Pittsburgh

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facility before being shipped to NASA's Jet

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Propulsion Laboratory in California for

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environmental testing. After that, it heads

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to Cap Canaveral for launch preparations,

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with the Flip rover joining it there.

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Avery: Launch is targeted for the fourth quarter of

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2026 with a SpaceX Falcon Heavy.

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So we may be watching this one land before

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the year's out.

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Anna: This mission comes in the wake of Voyager

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Technology's acquisition of Astrobotic in a

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deal valued at up to $300 million.

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So the company arrives at this milestone

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moment with new resources and a new parent.

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Thornton summed it up. This lander will

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be part of the cornerstone of building the

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moon base on the surface of the moon from a

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Avery: company that started nearly two decades ago

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and, um, has had its share of heartbreak.

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Here's hoping Griffin sticks The Landing

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Story

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Anna: 5, and this is one of my favorites.

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Today, an asteroid with an extraordinarily

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rich life story, now told in remarkable

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detail. Thanks to NASA's Lucy spacecraft.

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Avery: Lucy is on its way to study the Trojan

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asteroids, the ancient rocky bodies that

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shared Jupiter's orbit and are considered

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time capsules from the early solar system.

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But on April 20 last year, it made a

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practice flyby of a small main belt

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asteroid called 52246.

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Anna: Donald Johansen, named after the

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paleoanthropologist who discovered Lucy, the

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famous hominin fossil, which is a lovely bit

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of naming symmetry.

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Avery: The flyby was brief, just a close pass

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at 960km, but it was

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extraordinarily productive. And the results

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published yesterday in the journal Science

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reconstructed a 155 million

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year biography of this little world.

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Anna: The first thing you notice from the Lucy

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images is Donald Johansen is a

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contact binary. Two distinct

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lobes of rock fused together at a

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narrow neck, like a, ah, cosmic

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snowman. If snowmen were made of ancient

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asteroid rubble.

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Avery: The team led by Simone Markey at the

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Southwest Research Institute mapped craters

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across both lobes and found them saturated.

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So old that new craters are simply

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obliterating older ones. Based on impact

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statistics for the main asteroid belt, the

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surface is at least 40 million years old.

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Anna: That's consistent with Donald Johansen

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being a member of the Origin asteroid

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family. A, ah, collection of fragments from a

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parent body that was catastrophically

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destroyed around 155

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million years ago. The two lobes are

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likely pieces of that original smash up

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that eventually found each other and merged.

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Avery: But here's where it gets genuinely

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fascinating. The neck connecting the two

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lobes is younger than the lobes themselves,

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smoother, with far fewer craters,

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estimated as less than 20 million years old.

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So how do you get an old body with a young

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neck?

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Anna: The answer lies in the asteroid's

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rotation. Lucy confirmed that Donald

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Johanson rotates extraordinarily

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slowly once every

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252.6

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hours. That's more than 10 Earth days

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per rotation. And it's tumbling as

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well, with a second wobbling period of

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455 hours.

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Avery: This ultra slow spin is the key to

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everything. When contact binaries first form,

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they're typically spinning fast. Centrifugal

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force counteracts gravity and pushes material

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out towards the ends. But over millions of

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years, pressure from sunlight, a subtle

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but relentless force called the YORP effect,

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gradually slows the rotation

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Anna: once the spin rate drops below a critical

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threshold, somewhere around once every

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10 hours. For Donald Johansson,

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gravity takes over from centrifugal force

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and suddenly loose material on the smaller

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lobe starts sliding toward the larger one,

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like sand flowing down a hill.

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Avery: Every new impact rattles the asteroid. More

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landslides, more regolith flowing towards the

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center. The net gets built up over time,

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layer by layer, smoothed by millions of

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slow motion avalanches. That's why it's

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younger than the rest of the body.

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Anna: What I love about this story is that it shows

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what a brief flyby can actually reveal

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when you have the right instruments and the

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right analysis. The Lucy team measured

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this asteroid for a matter of hours and

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pieced together a geological narrative

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spanning over a hundred million years.

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Avery: And this was the practice run. In August

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2027, Lucy will fly past Eurybates,

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a Trojan asteroid more than 10 times the

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size of Donald Johansson. If we learned this

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much from a quick pass at a small main belt

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rock, the Trojan, uh, encounters are going to

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be extraordinary.

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Anna: The solar system's history, one flyby

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at a time.

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Avery: And our final story today is one that

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deserves a moment of genuine celebration.

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Anna: NASA's Perseverance rover has now

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driven more than 26.2

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miles across the surface of Mars.

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In other words, it has completed a

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marathon on another planet.

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Avery: Percy, as the team affectionately calls it,

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landed in Jezero crater on 18th February

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2021. It has been trundling across the mart

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landscape ever since, drilling rocks,

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collecting samples, taking panoramic images,

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and doing science that would have seemed like

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science fiction not long ago.

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Anna: 26.2 miles, or

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42.2 kilometers in just

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over five years. That sounds slow.

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And compared to a human marathon runner, it

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obviously is. But remember that for

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Percy, driving is the interruption between

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science. The rover's days are filled with

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drilling, abrading rock, surfing surfaces,

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calibrating instruments, and studying ancient

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geology.

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Avery: And, um, the terrain it's traversing now,

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beyond the western rim of Jezero Crater,

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is some of the most scientifically valuable

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ground of the entire mission. Ancient

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fractured rocks, igneous minerals that

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predate the formation of Jezero itself.

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Geological structures that may preserve

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evidence of Mars earliest history.

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Anna: Perseverance is also approaching the distance

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record for any rover on another planet. The

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record currently belongs to NASA, NASA's

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Opportunity rover, which managed

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45.16 kilometers over

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roughly 14 years before a global

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dust storm ended its mission in 2018.

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Percy is closing in on that record, with the

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mission planned to continue through at least

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2028.

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Avery: To put that in perspective, if you were

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standing on the Martian surface watching

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Perseverance go by, you'd be experiencing

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temperatures that could drop to minus 8, 80

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degrees Celsius. Overnight, breathing nothing

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at all and being bombarded by radiation.

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The fact that this rover not only survives

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but thrives in that environment and keeps

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doing world class science is a genuine

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engineering marvel.

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Anna: Mars One Soul at a Time

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Congratulations to the entire Perseverance

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team on this milestone.

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Avery: And that wraps up today's edition of

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Astronomy Daily. Your Friday fix of the

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00:18:23.370 --> 00:18:25.850
best space and astronomy news from across the

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cosmos.

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Anna: A beautiful lineup today. Salty alien

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skies belching black holes, a

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landmark moon lander, the remarkable story of

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an asteroid that's been renovating itself for

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millions of years, and a little rover hitting

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a major milestone on the Red planet.

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Avery: If you enjoyed today's show, please take 30

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00:18:45.430 --> 00:18:47.510
seconds to leave us a review. Wherever you

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00:18:47.510 --> 00:18:49.910
listen, it makes a genuine difference in

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00:18:49.910 --> 00:18:51.470
helping new listeners find us.

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00:18:51.630 --> 00:18:53.790
Anna: You can follow us on social media at

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00:18:53.790 --> 00:18:56.510
AstroDaily Pod, visit our website at

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00:18:56.510 --> 00:18:59.290
astronomydailyio for show notes and

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00:18:59.290 --> 00:19:01.250
transcripts. And if you're watching on

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00:19:01.250 --> 00:19:03.370
YouTubeMusic, subscribe and hit the bell so

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00:19:03.370 --> 00:19:04.650
you never miss an episode.

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Avery: From all of us here at Astronomy Daily and

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00:19:07.650 --> 00:19:10.370
the bytes.com podcast network, have a

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00:19:10.370 --> 00:19:12.930
wonderful weekend. Keep looking up and we'll

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see you back here on tomorrow with our

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weekend wrap.

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Anna: Clear skies, everyone.