Cosmic Secrets in Ocean Rocks, Record-Breaking Ariane Launch, and a Salty Pink World Revealed

0:00 Anna: Hello and welcome to Astronomy Daily,

0:02 your daily dose of space news from across the

0:05 cosmos. I'm Ana.

0:07 Avery: And I'm avery. It's Saturday the 20th of

0:10 June, 2026, and that means it's time for

0:13 our weekend space and astronomy news wrap.

0:15 Anna: As always, we're kicking things off with two

0:18 brand new stories you won't have heard

0:20 anywhere else on the show, including a

0:23 genuinely goosebump inducing tale about a

0:26 rock pulled up of the Pacific Ocean 50 years

0:28 ago that's just rewritten part of COSM

0:32 history.

0:32 Avery: Then we'll wind back to the week and bring

0:35 you the four biggest stories that had

0:37 everyone talking a new crew for the moon, a

0:39 salty pink world, a daring rescue mission,

0:42 and an asteroid chase 50 years in the making.

0:45 Anna: If you're watching on YouTubeMusic, smash

0:47 that subscribe button and let's get straight

0:50 into it.

0:51 Avery: Let's start with a story that genuinely gave

0:53 me chills. Anna. Back in 1976,

0:56 a research expedition hauled up a small lump

0:58 of rock from the floor of the Pacific Ocean.

1:00 Nobody at the time had any idea what they

1:03 were really holding.

1:04 Anna: Fifty years later, scientists have worked out

1:07 exactly what's hiding inside it. And it's

1:10 older and stranger than anyone expected.

1:13 Avery: The rock is a chunk of what's called ferro

1:15 manganese crust, basically slow growing

1:18 mineral deposits that build up on the

1:19 seafloor over millions of years, almost like

1:22 tree rings.

1:23 Anna: And buried inside this particular piece are a

1:26 few hundred atoms. Atoms, not grams

1:29 of radioactive plutonium isotopes,

1:33 Avery: which doesn't sound like a lot, because it

1:35 isn't. But those atoms didn't come from

1:37 anywhere on Earth. More than a hundred

1:39 million years ago, two neutron stars, the

1:42 impossibly dense leftover cores of giant

1:44 stars, crashed into each other in a

1:46 cataclysmic event called a kilonova.

1:49 Anna: And a kilonova is basically a heavy

1:52 element factory. The collision is so

1:54 violent and so energetic that it forges

1:57 elements for far heavier than iron, including

2:00 gold, platinum, and, yes, plutonium.

2:03 That blast sent a rain of these freshly

2:06 minted elements out across space.

2:09 Avery: Some of that stellar debris eventually

2:10 drifted down through our solar system,

2:12 through Earth's atmosphere, and settled into

2:14 the ocean, where over unimaginable spans of

2:17 time, it got slowly locked into this growing

2:20 crust of rock on the seafloor.

2:22 Anna: The study was published just yesterday. And

2:25 what's remarkable is that the ratios of these

2:27 plutonium isotopes act like

2:30 a fingerprint. They give researchers their

2:32 strongest physical clues yet about

2:35 exactly what kind of event created them

2:38 and roughly how long ago it happened.

2:40 Avery: It's wild to think Earth has basically been

2:42 an accidental evidence locker this whole

2:45 time, quietly filing away atomic level proof

2:48 of cosmic violence before there was complex

2:50 life on this planet at all.

2:52 Anna: A little lump of rock dredged up half a

2:54 century ago, finally giving up one of its

2:57 biggest secrets. Beautiful story.

3:00 Avery: From ancient cosmic violence to some very

3:03 modern rocket engineering.

3:04 Europe's Ariane 6 just broke a record that

3:07 had stood for 13 years.

3:09 Anna: This happened on Wednesday 17 June.

3:12 An upgraded Ariane 6. 4 lifted

3:15 off from Europe's spaceport in French Guiana,

3:18 carrying 36Amazon LEO broadband

3:21 satellites. That's the Constellation formerly

3:23 known as Project Cooperation 36

3:26 satellites.

3:27 Avery: Doesn't sound like a record breaker on its

3:28 own, but here's the kicker. This was the very

3:31 first flight of Ariane 6 4's new

3:33 P160 boosters. They're an upgrade on the

3:36 previous P120 boosters, about 1 meter

3:39 longer and able to hold up to 156

3:42 tons of propellant each.

3:44 Anna: That gives roughly a 10% performance boost

3:47 and pushes Ariane 6. 4's lift capacity

3:50 to about 22 tons to low Earth orbit.

3:53 Combined with those 36 satellites, it added

3:56 up to the HEAV heaviest payload ever launched

3:59 by an Arian rocket, beating a record that had

4:01 stood in 2013 when an Ariane

4:04 5 delivered the ATV cargo vehicle

4:07 Albert Einstein to the International Space

4:09 Station. The satellites were deployed into

4:12 orbit about 465km

4:15 up over the course of just under two hours.

4:18 And Arianespace confirmed every single one

4:21 separated successfully.

4:23 Avery: This was also the 8th Ariane 6 launch overall

4:26 and the hundredth Amazon LEO satellite lofted

4:29 by Arianespace specifically out of a planned

4:32 18 launch contract with Amazon. It's

4:34 a solid milestone for a rocket that, let's be

4:37 honest, had a famously bumpy road to its

4:40 2024 debut.

4:41 Anna: And it matters. Beyond the bragging rights,

4:44 Amazon's been racing against an FCC

4:46 deadline to get half its Constellation up by

4:49 the end of July, competing for SkySpace

4:52 against SpaceX's Starlink, which already

4:54 has more than 10,000 satellites in orbit.

4:57 Avery: Whichever side of the satellite mega

4:59 constellation debate you sit on, Watching

5:02 Europe's flagship rocket flex some genuinely

5:05 upgraded muscle is fun to see.

5:07 Anna: And that brings us to the part of the show

5:09 you've been waiting for. Our uh, look back at

5:11 the four biggest stories that shaped the week

5:14 in space and astronomy. We've got updates

5:16 on a couple of these too, so even if you

5:19 caught them earlier in the week, stick

5:21 around. There's fresh detail in each one.

5:23 Avery: Story number three, and for my money, the

5:26 biggest human spaceflight Story of the Week

5:28 On Tuesday, NASA finally named the crew for

5:31 Artemis 3.

5:32 Anna: At a ceremony in Houston, NASA

5:35 Administrator Jared Isaacman introduced the

5:38 four astronauts who will fly this critical

5:40 test mission Commander Randy Bresnik,

5:43 ESA pilot Luca Parmitano, and

5:45 mission specialists Frank Rubio and Andre

5:48 Douglas. Bob Hines will train alongside them

5:51 as backup crew.

5:52 Avery: And here's the bit that got me towards the

5:54 end of the ceremony, the Artemis 2 crew, Reed

5:57 Wiseman, Victor Glover, Christina Cook and

6:00 Jeremy Hansen physically handed over the

6:02 baton they carried around the moon and back

6:05 in April, passing it to Bresnik's crew as a

6:08 symbol of the relay continuing toward the

6:10 lunar surface.

6:11 Anna: Now. Important distinction here. Artemis

6:14 3 isn't the landing mission itself. It's a

6:17 two week test flight that stays in low Earth

6:19 orbit, designed to test rendezvous and

6:22 docking procedures between the Orion

6:24 spacecraft and the commercial landers being

6:26 built by SpaceX and Blue Origin.

6:29 Avery: Think of it as the Artemis program's

6:31 equivalent of Apollo 9, proving the hardware

6:34 works together before anyone attempts an

6:36 actual landing. It's currently targeted for

6:38 as early as late 2027, with the lunar

6:41 surface landing itself still aimed at

6:44 2028.

6:45 Anna: A couple of nice personal notes. This will be

6:48 Andre Douglas's first ever spaceflight after

6:50 serving as backup crew on Artemis 2, and

6:53 Luca Parmitano is a fan favorite in Europe.

6:56 Some of you will remember him from a 2013

6:59 spacewalk where his helmet began filling with

7:01 water. A genuinely dangerous moment he

7:04 handled with real composure.

7:06 Avery: A strong, experienced crew for what NASA

7:09 itself is calling one of the most complex

7:11 missions it's ever undert. We'll be watching

7:14 this one closely.

7:15 Anna: Story four takes us 57 light years

7:18 away to a strange little world astronomers

7:21 have nicknamed the pink planet.

7:23 GJ504b was first

7:26 directly imaged back in 2013 and

7:29 stood out immediately for its odd magenta

7:32 color. This week, a Northwestern University

7:34 led team using JWST

7:37 confirmed something theorized about objects

7:39 like this for future 15 years. Its atmosphere

7:42 is wrapped in salty clouds unlike

7:45 anything seen on a substellar object before.

7:49 Avery: This is the first direct evidence of salt

7:51 clouds in the atmosphere of a cold companion

7:53 object, and GJ504B earns

7:56 that description. At around 550 degrees

7:59 Fahrenheit, it's actually the coldest object

8:01 of its kind ever directly imaged.

8:04 Anna: And that raises a genuinely open question.

8:07 Is is GJ504B really a

8:10 planet? Or is its mass actually large enough

8:13 to make it a brown dwarf? The line between

8:15 giant planet and failed star gets blurry

8:18 out at the cold end of the scale, and this

8:20 object sits right on that boundary.

8:23 Avery: Either way, it's, uh, a gorgeous

8:24 demonstration of just how much chemistry

8:27 JWST can now tease out of worlds

8:30 we can't visit, can't sample, and can

8:33 only study through the faintest whispers of

8:35 infrared light. Salt clouds on an

8:38 alien world? Try saying that without smiling.

8:41 Next up, story five is an update on a daring

8:44 rescue mission we first told you about

8:46 earlier this week. And it's now properly

8:48 underway.

8:49 Anna: NASA's Neil Jarrell Swift Observatory

8:52 has been watching gamma ray bursts from orbit

8:55 since 2004, but its orbit has been

8:58 decaying faster than expected, thanks to drag

9:00 from recent high solar activity. And without

9:03 help, it could re enter and burn up by later

9:06 this year.

9:07 Avery: The fix is a robotic servicing spacecraft

9:10 called Link, built by Catalyst Space

9:12 Technologies, designed to rendezvous with

9:15 Swift, grapple onto fixtures that were only

9:18 ever meant to be used on the ground before

9:20 its original 2004 launch, and boost

9:22 it up to a Safer orbit around 600

9:25 km high.

9:26 Anna: And here's the fresh development. On

9:29 Thursday, 18 June, Northrop

9:31 Grumman's Stargazer aircraft, the very last

9:34 flying Lockheed L1011

9:37 Tristar, departed NASA, NASA's Wallops

9:40 Flight Facility in Virginia carrying Link

9:42 tucked inside a, uh, Pegasus XL

9:45 rocket. It's now routing via California

9:48 and Hawaii toward Kwajalein Atoll in

9:51 the Marshall Islands.

9:52 Avery: Launch is targeted for June 27th.

9:55 Stargazer will carry Pegasus to around

9:57 40,000ft. Drop it and the rocket

10:00 will fire Link into orbit in about 10

10:03 minutes. That's the easy part.

10:05 Anna: The hard part comes after Link has to

10:08 chase down and successfully grab a satellite

10:10 that was never designed to be captured. If it

10:13 works, it'll be the first time a commercial

10:15 vehicle has captured an unprepared US

10:18 Government satellite and the first capture of

10:21 a science satellite never built for it.

10:24 Avery: High stakes, fast turnaround. This whole

10:27 mission went from concept to launch pad in

10:29 under a year. One NASA astrophysics

10:32 director put it bluntly. Nobody thought

10:34 they'd get this far. We'll bring you the

10:36 result the moment it happens.

10:38 Anna: And our final story of the week takes us to a

10:41 tiny, strange little asteroid that's been

10:44 quietly tagging along with Earth for

10:46 centuries.

10:47 Avery: China's Tianwen 2 spacecraft launched

10:50 all the way back in May last year on a

10:53 mission to collect a sample from near Earth

10:55 asteroid Kamo Aloa, a, uh, quasi

10:58 satellite only 40 to 100 meters across

11:01 that loops around a in lockstep with our own

11:03 planet.

11:04 Anna: According to mission design and amateur radio

11:07 trackers, since China's space agency has gone

11:10 fairly quiet on official updates

11:12 Tianwen 2 completed its orbital

11:14 insertion at the asteroid on June 7.

11:18 Avery: Since then, observers in Germany using a 20

11:21 meter dish have picked up a series of much

11:23 smaller course Correction Burns between June

11:25 11th and 14th, almost certainly using

11:28 the spacecraft's ion engines to fine tune its

11:31 position ahead of the main event.

11:33 Anna: That main event rendezvous and the actual

11:36 sample collection is now expected around July

11:39 4th. Kamala Loa is scientifically

11:42 fascinating because some researchers think it

11:44 may be a fragment blasted off the moon by an

11:47 ancient impact, though a study published just

11:50 this month complicates that picture somewhat

11:52 based on how its surface has weathered.

11:55 Avery: Whatever its true origin. After sample

11:57 collection, Tianwen 2 will head home with its

12:00 haul before swinging back out to chase down a

12:03 Comet in the2030s, a patient

12:05 decade spanning mission finally closing in on

12:08 its first big milestone.

12:10 Anna: And that wraps up our weekend space and

12:12 astronomy news wrap from ancient ocean rocks

12:15 to record breaking rockets, a new moon crew,

12:18 a salty pink world, a daring rescue,

12:21 and a patient asteroid chase.

12:23 Avery: If you enjoyed today's episode, the best

12:26 thing you can do is share it with a fellow

12:28 space nerd. And we'll see you back here

12:30 Monday for more from across the cosmos.

12:33 Anna: I'm Anna.

12:34 Avery: And I'm Avery. Clear Skies, everyone.