Aussie Satellite Snapshots, Space Command's Close Encounter, and the Truth About Water Worlds

0:01 Anna: Welcome to Astronomy Daily, the podcast.

0:04 Avery: Bringing you the latest in space and

0:06 astronomy news. I'm Avery.

0:08 Anna: And I'm Anna. Today we've got a busy

0:10 show. We'll be talking about an Australian

0:13 satellite that's taking selfies in orbit.

0:15 Avery: A close encounter between US and UK military

0:18 satellites, and a busy week for rocket

0:21 launches around the globe.

0:23 Anna: Plus we'll dive into some fascinating new

0:25 research that questions the existence of

0:28 so called water worlds.

0:30 Avery: And we'll have headlines including a, uh,

0:33 potential signal from a wormhole.

0:35 Let's get started.

0:36 Anna: First up, let's head down under.

0:39 Australia's Spirit nanosatellite has

0:42 just wrapped up its first mission phase after

0:44 an impressive run.

0:46 Avery: Impressive is right. It's been in orbit for

0:49 over 600 days, circling the Earth more than

0:51 9,000 times since it launched on a

0:54 SpaceX Falcon 9.

0:56 Anna: For a satellite that's only about 11.5

0:59 kilograms, that's quite a journey. The

1:02 initial phase about checking its systems,

1:05 making sure everything was working correctly,

1:07 and.

1:08 Avery: They did this in the coolest way possible. It

1:10 has a selfie stick to take a photo of itself

1:13 against a backdrop of Earth. I love that it

1:16 confirms everything is deployed and

1:18 operational.

1:19 Anna: It's not just for show though. Spirit's main

1:22 job is pretty serious. It carries an

1:24 instrument from the Italian Space Agency

1:27 designed to detect gamma ray bursts.

1:30 Avery: And this is where it gets really clever.

1:32 Spirit also has a built in autonomous

1:34 repointing system. So when it detects a

1:37 gamma ray burst, it can automatically and

1:39 very quickly turn itself to face the source

1:42 of the explosion. This allows it to gather

1:45 more detailed data in the crucial first

1:47 moments.

1:48 Anna: That's a critical capability. Often the

1:51 most interesting information from these

1:53 events fades very quickly. By

1:55 reacting instantly, without waiting for

1:58 commands from the ground, Spirit can catch

2:00 details other telescopes might miss.

2:03 It's a great example of how AI and automation

2:06 are, uh, transforming space science.

2:08 Avery: And for our listeners, gamma ray bursts, or

2:11 GRBs, are some of the most powerful

2:13 explosions in the universe. They come from

2:16 incredible cosmic events. Like two neutron

2:19 stars colliding.

2:20 Anna: Exactly. The idea is that Spirit is a

2:23 pathfinder, a, uh, prototype for a future

2:25 constellation of satellites. This network

2:28 will be able to quickly spot these gamma ray

2:30 bursts and alert astronomers on the ground so

2:33 they can point their telescopes at the source

2:36 almost immediately.

2:37 Avery: It's a fantastic example of international

2:40 collaboration and a big step for the

2:42 Australian space industry. A tiny satellite

2:45 with a huge mission.

2:47 Next, we're moving from scientific

2:49 collaboration to a major display of military

2:52 partnership in or. The US Space Command just

2:54 did something for the first time ever with

2:57 the.

2:57 Anna: Uk, they performed what's called a

2:59 rendezvous Proximity operation

3:02 or rpo. In simple terms

3:05 they flew one of their spacecraft very close

3:08 to a UK military satellite to

3:10 inspect it.

3:11 Avery: And this wasn't in low earth orbit. This

3:14 happened 22,000 miles up in

3:17 geostationary orbit where many critical

3:19 communications satellites live. The US

3:22 spacecraft approached the UK's Skynet

3:25 5A communications satellite.

3:27 Anna: The official line is that this was a peaceful

3:29 inspection, a demonstration of trust and

3:32 cooperation between allies. It shows they

3:35 can help each other out, say if a friendly

3:38 satellite is malfunctioning and they need a

3:40 closer look.

3:41 Avery: But there's another layer to this, isn't

3:43 there? It also sends a very clear message to

3:45 other nations. It demonstrates, uh, a

3:47 capability to get extremely close to any

3:50 satellite in that orbit.

3:51 Anna: Friendly or that's the subtext,

3:54 yes. US Space Command's General Stephen

3:57 Whiting didn't mince words. He called it a

4:00 demonstration of the war fighting advantage

4:03 their coalition provides. It's a powerful

4:05 statement about their capabilities in what's

4:08 becoming an increasingly contested domain.

4:11 Avery: So a friendly checkup, but with a very strong

4:14 geopolitical message attached.

4:16 Anna: Speaking of people in space, we should

4:19 mention that NASA just introduced its newest

4:21 class of astronauts.

4:23 Avery: That's right, the 24th class. It's a

4:26 diverse group and one interesting name on the

4:28 list is a former SpaceX crew member

4:31 who was part of the all civilian Inspiration4

4:34 mission. It's great to see that pipeline from

4:36 commercial spaceflight into the official NASA

4:39 corps.

4:40 Anna: It's been a very busy week for launches.

4:42 Let's do a quick roundup.

4:44 Avery: Let's start with the usual suspect, SpaceX.

4:47 On Monday they launched another 22

4:49 Starlink satellites from Cape Canaveral.

4:52 What's amazing here is the booster used for

4:55 this Falcon 9 flight. It was its 15th

4:58 trip to space and back.

5:00 Anna: That reusability is still mind boggling.

5:03 Over in New Zealand, Rocket Lab is gearing up

5:06 for its 53rd Electron launch. This one

5:09 is for the US Space Force and has a very

5:11 cool mission name. Methane to be

5:14 Max.

5:15 Avery: I like that. So what's it doing?

5:17 Anna: It's deploying a satellite that will try to

5:19 demonstrate producing methane in orbit.

5:22 So this is a key technology for in

5:24 situ resource utilization. The

5:27 idea is to eventually create rocket fuel

5:30 from resources found on the moon or Mars,

5:33 like water ice and the martian atmosphere so

5:36 you wouldn't have to.

5:36 Avery: Carry all your return fuel with you. That's a

5:39 game changer for long duration missions.

5:41 Anna: Absolutely. And finally, not to be left

5:44 out, China also had a successful launch,

5:47 sending up the Yao' Gon 44 reconnaissance

5:50 satellite on a long March 2D rocket

5:53 launch. Uh, a busy week for all the major

5:54 players.

5:55 Avery: Okay, before we get to our last big story,

5:58 I have to bring up this wild theory I read

6:01 about. Remember that strange

6:03 gravitational wave signal from 2019

6:06 GW 1905, 21.

6:09 Anna: Vaguely. It was very short, just

6:12 a blip. Right. And it seemed to come from the

6:15 merger of two unusually massive

6:17 black holes.

6:19 Avery: Exactly. But it was so odd

6:22 that it's opened the door to more exotic

6:25 explanations. A new paper is floating the

6:28 idea that it m might not have been a standard

6:30 black hole merger at all. They suggest it

6:33 could be the echo of a collision that

6:35 happened in another universe and the signal

6:38 traveled to us through a wormhole.

6:40 Anna: Wow. Okay, that is definitely out

6:43 there. I assume the standard black hole

6:45 explanation is still the most likely one,

6:47 right?

6:48 Avery: Oh, absolutely. But the scientists say they

6:51 can't completely rule out this wormhole

6:53 hypothesis based on the data. It's a

6:56 fun thought experiment if nothing else.

6:58 Anna: All ah, right.

6:59 For our final story, let's talk about the

7:02 search for alien oceans. For years

7:05 there's been a really exciting idea about a

7:08 type of exoplanet called a uh, Hycean world.

7:11 Avery: Right. These are sub Neptunes, bigger than

7:13 Earth, but smaller than Neptune that are

7:16 thought to be completely covered in massive

7:18 deep oceans. Quintessential water

7:21 world from science fiction.

7:23 Anna: The theory was that these planets could form

7:25 with a huge amount of ice which would then

7:28 melt into a global ocean. But

7:31 a new study is pouring a little cold water

7:33 on that idea, pun intended. Of course.

7:37 New computer models suggest that it might be

7:39 very difficult for these massive oceans to

7:41 exist on the surface. When these planets

7:44 form, the immense pressure and heat in their

7:47 interiors would cause a chemical reaction.

7:50 Avery: Let me guess, the water doesn't stay on the

7:52 surface.

7:52 Anna: Exactly. The hydrogen and oxygen that

7:55 make up the water would likely get trapped

7:58 deep inside the planet's molten mantle.

8:00 The study concludes that planets with Oceans

8:03 making up 10 to 90% of their

8:06 total mass are very unlikely.

8:08 Avery: So the dream of a planet like Kamino from

8:11 Star wars might be less realistic. This is

8:14 particularly relevant because of the recent

8:16 hype around exoplanet K2

8:18 18b which some had claimed could be one of

8:21 the these hean worlds.

8:23 Anna: This research definitely tempers those

8:25 expectations. But it's not all bad news

8:28 for the search for life. The study also

8:30 suggests that the same process would make it

8:33 easier for planets with more modest Earth

8:35 like amounts of surface water to form.

8:38 Avery: So fewer giant water worlds, but potentially

8:40 more planets that look a little more like

8:42 home. I'll take that trade off. It's a great

8:45 reminder that our assumptions about how

8:46 planets work are constantly being tested and

8:49 refined.

8:50 Anna: And one last quick note for all the

8:52 stargazers out there. A brand new comet has

8:55 been discovered, and it could be a good one.

8:57 Avery: Ooh, tell me more.

8:59 Anna: It's called

8:59 C2025R2

9:03 Swan. It's already quite bright,

9:06 and there's a chance it could become visible

9:08 to the naked eye this October. For now,

9:10 you'll need binoculars to spot it.

9:12 Avery: When's the best time to look?

9:14 Anna: It will make its closest pass to Earth on

9:16 October 21st, so mark your calendars and

9:19 keep an eye on the sky. It's always a treat

9:22 when a new visitor graces our, uh, cosmic

9:24 neighborhood.

9:25 Avery: And that's all the time we have for today on

9:26 Astronomy Daily.

9:28 Anna: It certainly has been a full week to keep up

9:30 with these stories and more. Be sure to visit

9:32 our website.

9:34 Avery: Visit astronomydaily IO for more

9:37 space and astronomy news and to listen to all

9:39 our back episodes.

9:40 Anna: We'll be back tomorrow with more space and

9:42 astronomy news for you. See you then.

9:45 I'm Anna signing off.

9:47 Avery: And I'm Avery saying bye for today. Make sure

9:49 you get outside and look up. You never

9:52 know what you might see.