Why scientists launched two little robots to the moon

Summary

Podcast Summary: Short Wave – "Why scientists launched two little robots to the moon"

Date: June 19, 2026
Hosts: Regina Barber, Scott Detrow
Guest/Producer: Burleigh McCoy

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Episode Overview

In this lively episode of Short Wave’s monthly “Spacing out with Gina” segment, hosts Regina Barber and Scott Detrow team up with producer and fellow PhD scientist Burleigh McCoy for a rapid tour through recent breakthroughs in space exploration and astronomy. The trio discusses Japan's adorable, shape-shifting lunar robots, the ongoing scientific debate over the universe's expansion, and new details about NASA’s Artemis missions—including astronaut training in surprising locations on Earth. The conversation blends accessible science, light banter, and moments of awe about our ever-expanding knowledge of the cosmos.

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Key Discussion Points & Insights

1. Tiny Transformers on the Moon (00:47–06:08)

• Introduction to Robots:

  • Regina introduces small, autonomous, sphere-shaped robots sent to the Moon as part of Japan’s first successful lunar mission.
  • The robots, about baseball-sized, roll out of the lander, then expand to reveal a camera and use their halves as spinning wheels for movement.
    • “They're really small. They're really cute. They're round little guys about the size of a baseball.” — Regina Barber (01:52)
  • The comparison to Transformers is made playfully, though “not Optimus Prime”—they do shapeshift.

• Purpose and Function:

  • The robots' job: scouting lunar terrain for future, larger rovers; taking photos of both the surface and lander; and exploring terrain that’s otherwise hard to reach.
  • Their small mass (~0.5 pounds) makes them efficient and cost-effective for space travel.
  • Expert input:
    • “These are not expensive devices. You can have several of them, and if one or two fails, then you still have others.” — Roger Wiens, planetary scientist (05:25)

• Designed for Low Gravity:

  • The robots’ movement leverages low gravity, letting them “waddle” and even bounce on the Moon or other low-gravity bodies like asteroids or Mars.
    • “These could go to small asteroids where hopping is extremely easy… I can see these things going to a number of places. We’ll have transformers on various planets and asteroids eventually.” — Roger Wiens (05:52)
  • Hosts delight in the comparison to toddlers—explorative, expanding, and always “waddling around.”

Memorable Quotes:

• “Other than kind of waddling around and seeming like Wall E characters, what was their scientific job?” — Scott Detrow (04:49)
• “They're really small. They only weigh about a half a pound. And that's huge for space travel..." — Burleigh McCoy (05:04)

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2. The Debate Over the Expanding Universe (06:08–08:54)

• Background:

  • Almost 30 years ago, astronomers discovered the universe’s expansion was speeding up.
  • Recently, a group from Yonsei University in South Korea challenged this, suggesting the expansion is actually slowing down—a major, potentially revolutionary claim.
    • A new paper published last week reinforced the standard (speeding up) view, but debate continues.

• Measuring Expansion:

  • Astronomers use the brightness of special exploding stars (supernovae), correcting for factors like explosion duration and cosmic dust.
  • The Yonsei group argues missing corrections for the age of the supernova’s host galaxy could influence results, suggesting expansion slowdown if corrected.

• Scientific Community Response:

  • Most experts remain skeptical of the “slowing-down” hypothesis, citing decades of fine-tuning and alternative measurements supporting acceleration.
    • “The experts we spoke to were skeptical of the slowdown hypothesis.” — Burleigh McCoy (07:56)
    • “These kind of debates are what strengthen science. Scientists by nature are skeptical.” — Regina Barber, quoting astrophysicist Premvada Natarajan (08:09)
  • The consequences? If the universe’s expansion slowed or reversed, it could mean a “Big Crunch” instead of a cold, drifting end—though none of us will be around to find out.

Memorable & Lighthearted Quotes:

• “This is quite the big if true.” — Scott Detrow (07:47)
• “Instead of everything eventually drifting far apart... the universe could simply implode. What astronomers called the Big Crunch.” — Burleigh McCoy (08:37)
• “I'm Team Cold Death.” — Regina Barber (08:50)

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3. NASA’s Artemis Program and Astronaut Training (09:01–11:16)

• Artemis 3 Crew:

  • NASA has just selected the crew for its upcoming Artemis 3 mission, key for lunar preparation and beyond.
  • Scott interviews Andre Douglas, newly selected astronaut, about training—including a demanding 24-mile Icelandic hike to simulate lunar land navigation.
    • “We did a 24 mile hike in two days in Iceland just to go through a hard challenge of land navigation…” — Andre Douglas (as paraphrased by Scott Detrow, 09:17)

• Why Iceland?:

  • Iceland’s rocks and terrain closely mimic that of the Moon, continuing Apollo-program tradition.
    • “Apollo astronauts actually trained in Iceland, too, way back when and said it was the closest thing they had seen to the moon's surface.” — Regina Barber (09:55)
  • “Spacing out” hosts joke about field-tripping to Iceland to see both geology and the northern lights.

• Simulating Mars:

  • NASA also trains on Hawaii lava beds for Mars missions, sending astronaut candidates into remote fieldwork with communication delays.
  • At Johnson Space Center, a simulated Mars mission has four participants living in a 3D-printed habitat for over a year.

Memorable Quotes:

• “It's all a way to make sure our astronauts are super well prepared when someday they are out in space doing the real thing.” — Burleigh McCoy (10:46)
• “Sounds great. I think we need a spacing out field trip to Iceland then.” — Scott Detrow (11:07)

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Notable Moments & Lighthearted Banter

• Transformers and Toddlers:
  • The robots’ “waddling” is likened to burley’s toddler—curious and ever-expanding (02:22).
• Existential Stakes:
  • Hosts joke about the fate of the universe: “I'm Team Cold Death” (08:50) and, “don’t know which one I prefer” regarding cosmic endings (08:52).
• Floating Away:
  • As the episode closes, Scott jokes he's “floating away”—and Regina calls out, “Decelerating, he stopped” (12:12–12:14).

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Timestamps for Key Segments

| Segment Topic | Timestamp | |-------------------------------------------------|-------------| | Robots on the Moon — Introduction & Purpose | 00:47–05:16 | | Robots Designed for Low Gravity | 05:16–06:08 | | The Expanding Universe Debate | 06:08–08:54 | | NASA Artemis, Astronaut Training, Iceland | 09:01–11:16 | | Simulated Mars mission at Johnson Space Center | 10:46–11:07 | | Light banter/sign-off | 11:12–12:14 |

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Episode Tone & Language

• Inviting, Enthusiastic, and Playful: The hosts maintain a conversation brimming with curiosity, pop culture references, accessible analogies, and gentle ribbing.
• Scientifically Accurate Yet Approachable: The language balances expert insight and layperson context, making even high-level debates about cosmology understandable and fun.
• Community and Collaboration: Emphasizes science as a collective, skeptical, but ever-curious endeavor.

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This episode is a must-listen for anyone craving a bite-size, entertaining, and informative peek into our lunar future, cosmic mysteries, and the very human side of space exploration.

Transcript

[Commercial Announcer]

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[NPR Station Announcer]

You're listening to Short Wave from NPR.

[Regina Barber]

Hey, Shortwavers. Regina Barber here, and it's time for my favorite monthly episode of our space news segment, Spacing out with Gina. We're here today with my space buddy, my partner in Spacing out crime, All Things Considered host, Scott Detrow. Welcome back to the show, Scott.

[Scott Detrow]

I'm excited to be here. Since we last taped, I now have a giant picture of the moon at my desk, and I love it.

[Regina Barber]

You do? I've seen it.

[Scott Detrow]

It's big.

[Regina Barber]

And joining us today, Scott, is our producer, Burley McCoy Burleigh. Welcome to your first Spacing out with Gina.

[Burleigh McCoy]

Hey, Gina. Hey, Scott. I'm excited to be here. It sounds like my jam. I'm a big nerd.

[Scott Detrow]

I'm excited. I am excited you're here.

[Additional NPR Staff or Guest]

Welcome.

[Regina Barber]

She is a big nerd because she's the other PhD scientist on short Wave. So she's going to feel right at home in our nerd space, I think.

[Scott Detrow]

You know, I agree. I'll just represent all the non PhD holders out there and do my best.

[Regina Barber]

I have a question for both of you, though.

[Scott Detrow]

Yes.

[Regina Barber]

Have you seen any of the Transformer movies?

[Additional NPR Staff or Guest]

Of course.

[Regina Barber]

I haven't seen any of them. Whoa. Have you, Burley?

[Burleigh McCoy]

Oh, I've definitely seen some, and they were cool at the time, but, like, I think they're kind of forgettable. I don't know.

[Regina Barber]

It's true.

[Burleigh McCoy]

No hate mail, please.

[Regina Barber]

It's true. But, you know, just to link all of this together, our first story in this segment is about Transformers on the moon. But I'm gonna pop your bubble a little, Scott. It's not about Optimus Prime.

[Burleigh McCoy]

They're very different, but hopefully equally as cool.

[Scott Detrow]

Are they still robots in disguise?

[Regina Barber]

Yes, they still shapeshift.

[Scott Detrow]

Oh, okay. I'll take that.

[Regina Barber]

They're really small. They're really cute. They're round little guys about the size of a baseball. Essentially, they rolled out of this moon lander, and each half of the sphere moves outward, kind of expanding, revealing this cute little camera in the center. And the halves are now spinning wheels.

[Scott Detrow]

Okay, that's even better than a Transformer. So it's like. It's like a little car that rolls around then.

[Regina Barber]

Yeah, sort of. But they kind of waddle. Cause they can kind of waddle over hard terrain and navigate. They navigate on their own. And this was a test for future explorations.

[Burleigh McCoy]

Oh my God. Waddling around. This reminds me of my toddler a little bit. Like always exploring, always expanding. Which brings me to our next topic, the expansion of the universe.

[Scott Detrow]

Oh, I'm just gonna applaud that. Really smooth transition. Congratulations. What's the latest, though, on the expanding universe?

[Burleigh McCoy]

So there's some drama in the astronomy world about how our universe is expanding. Some scientists are debating this right now and. And the stakes of that debate, just the fate of the universe, though most astronomers are still on one side of the debate.

[Regina Barber]

Right. Like me.

[Scott Detrow]

And we're gonna talk about Artemis 2 and Artemis 3, which now has a crew.

[Regina Barber]

Yep, that's right, Scott. So today on the show, we go from the moon to the farthest reaches of the cosmos and back. You're listening to Shortwave, the science podcast from N.

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Support for this podcast and the following message come from E Trade from Morgan Stanley. Simplify your finances and discover the convenience of investing in banking all in one place. Plus, get up to $1,500 when you open a brokerage account with a qualifying deposit today. Learn [e-mail] offer banking products and services are provided by Morgan Stanley Private bank, national association member FDIC terms and other fees apply. Investing involves risks. Morgan Stanley Smith Barney ll membercipic this message comes from Viking. Committed to exploring the world in comfort. Journey through the heart of Europe on an elegant Viking longship with thoughtful service, destination focused dining and cultural enrichment on board and on shore. And every Viking voyage is all inclusive with no children and no casinos. Discover [e-mail] this message comes from Schwab. With the new Schwab Teen Investor account, teens can gain hands on investing experience. It's co owned by you and your teen, so you can monitor the account while your teen learns how to invest and manage money. Learn [e-mail] okay, Scott Burley, I'm gonna

[Regina Barber]

start with these little cute autonomous robots that, you know, strolled on the moon.

[Scott Detrow]

I got a bunch of questions. Let's just start with why, though. Why they were on the moon? You said it was for testing.

[Burleigh McCoy]

Yeah, they were part of the first successful Japanese lunar mission that landed on the moon a couple years ago. And there's a new study out last week in the journal Science Robotics analyzing how these little guys performed up there on the lunar surface.

[Scott Detrow]

Other than kind of waddling around and seeming like Wall E characters, what was their scientific job?

[Regina Barber]

So they took a lot of pictures of the moon's surface and of the lander. They're basically scouting out the terrain ahead of bigger rovers and going places they can't.

[Burleigh McCoy]

And Scott, just to underline this, they're really small. They only weigh about a half a pound. And that's huge for space travel, right? The lighter something is, the easier and cheaper it is to put up into space.

[Regina Barber]

And I talked to Roger Wiens, a planetary scientist who didn't work on this program, and he was thoroughly impressed. He said that the redundancy was a huge benefit to these devices.

[Additional NPR Staff or Guest]

These are not expensive devices. You can have several of them, and if one or two fails, then you still have others.

[Scott Detrow]

One other thing, though, I'm thinking about the fact that the Moon has one sixth of the Earth's gravity. So does that affect how they move around?

[Burleigh McCoy]

Totally, yeah. These little guys actually kind of bounce, though. So it's another reason why they're super cool. They're designed for low gravity so they can explore other places like Mars or even asteroids. Here's Roger again.

[Additional NPR Staff or Guest]

These could go to small asteroids where hopping is extremely easy. In fact, you got to make sure you don't hop out of out of orbit or something like that. So, yeah, I can see these things going to a number of places. We'll have transformers on various planets and asteroids eventually.

[Scott Detrow]

Okay, this was a really fun start. We need to shift to something much more existential, though, for all of us, and that is our ever expanding universe. First of all, remind us what this debate has focused on over recent decades.

[Burleigh McCoy]

Okay, so, Scott, almost 30 years ago, astronomers discovered that our universe is not only expanding, but that expansion is speeding up. But in the last few years, a group of scientists shook up that understanding by claiming that the expansion isn't speeding up, but slowing down. Now, a paper out last week in the journal Monthly Notices of the Royal Astronomical Society pushes back and the old framework still stands, continuing the debate.

[Scott Detrow]

So we're back to expanding.

[Regina Barber]

Expanding and accelerating.

[Scott Detrow]

Okay, okay. So given that we're back to that point of view, what do the expansion of the universe is slowing down, folks say to that.

[Regina Barber]

The group of scientists at Yonsei University in South Korea stands by their work. They already posted a rebuttal to this paper. And they say that the standard way astrophysicists measure universe expansion now is fundamentally flawed.

[Scott Detrow]

So for the non astrophysicists out there, remind us how you measure this.

[Regina Barber]

I'm gonna let Burleigh do this.

[Scott Detrow]

Okay. Yeah.

[Burleigh McCoy]

So astronomers basically measure the brightness of a special type of exploding star, a supernova, and then correct for things like how long it explodes or how Much dust is in the way.

[Regina Barber]

And this South Korean team has said astronomers, we haven't been including the age of the star's home galaxy in those corrections. So the math is off. And when you include that, the final answer is that the expansion of the universe is slowing down, which would be a massive discovery if that were true.

[Scott Detrow]

This is quite the big if true.

[Regina Barber]

Exactly.

[Scott Detrow]

So, okay, so given all of that though, what is the consensus among other astronomers?

[Burleigh McCoy]

So the experts we spoke to were skeptical of the slowdown hypothesis. They say the community has been fine tuning the supernova method for almost 30 years. And there are other methods that point to the universe's expansion speeding up.

[Regina Barber]

Yeah. We talked to Premvada Natarajan, an astrophysicist from Yale University who wasn't involved in this work, and she's still skeptical. But she says these kind of debates are what strengthen science. Scientists by nature are skeptical.

[Scott Detrow]

And even for an idea that has

[Burleigh McCoy]

been validated and accepted. Right.

[Regina Barber]

If there is a new argument, we

[Scott Detrow]

do take it seriously and we interrogate it. And it's a low stakes debate. Right. Because it's only just like the fate of the universe that that's, that's at stake.

[Burleigh McCoy]

Instead of everything eventually drifting far apart from each other and dying a cold death billions of years from now, the universe could simply implode. What astronomers called the Big Crunch. Sadly, none of us are going to be around to see that.

[Regina Barber]

I'm Team Cold Death.

[Scott Detrow]

Don't know which one I prefer.

[Burleigh McCoy]

Hard. Hard to choose, huh?

[Scott Detrow]

Yeah, non issue for me. I guess something that is happening in our time spans though.

[Regina Barber]

Yeah.

[Scott Detrow]

Our favorite NASA program, Artemis. We've got to talk about it.

[Regina Barber]

Totally. The crew for the next mission, Artemis 3 was just selected. And this is the mission that will do lots of maneuvers in space in low Earth orbit. Scott, you spoke with one of the newly selected astronauts, right?

[Scott Detrow]

I did. The day he was selected, I talked with Andre Douglas and one of the things he talked about was going on training missions. He was on the backup Crew for Artemis 2 and trained alongside them. And one of the things they did was go to Iceland. We did a 24 mile hike in two days in Iceland just to go through a hard challenge of land navigation as if we're, you know, learning how to be really good operators. And they do this, you know, as you know, because this mission is supposed to help prepare them for future lunar explorations. So they're looking for places on Earth that are kind of analogs of the Moon of lunar conditions.

[Regina Barber]

Yeah. And it's also about geology like the rocky terrain and the actual rock compositions are very similar between the moon and Iceland. Apollo astronauts actually trained in Iceland, too, way back when and said it was the closest thing they had seen to the moon's surface. Two NASA astronauts are going back there this July to train in Iceland.

[Scott Detrow]

And this isn't just for lunar missions. Right. They're actually NASA's. It's farther away, but they're trying to simulate Mars as well right now.

[Regina Barber]

Yeah, yeah.

[Burleigh McCoy]

So they've had astronaut hopefuls trek around the lava beds in Hawaii Volcanoes national park with big packs on their backs doing geological fieldwork and dealing with very limited and very delayed communications from a simulated mission control. It's all a way to make sure our astronauts are super well prepared when someday they are out in space doing the real thing.

[Regina Barber]

And, Scott, there is a simulated Mars mission happening right now at NASA's Johnson Space center in Houston. NASA has four researchers in this 3D printed habitat doing experiments as if they're living on Mars. They went in last October, and they'll stay inside for a little over a year. And maybe, you know, we'll come back and talk about that when they emerge.

[Scott Detrow]

Sounds great. I think we need a spacing out field trip to Iceland then.

[Burleigh McCoy]

Let's do that.

[Regina Barber]

Oh, my gosh. And then we can see the northern lights too, which we've always talked about.

[Scott Detrow]

Yes, yes.

[Commercial Announcer]

Okay.

[Scott Detrow]

Remote show in Iceland. Done.

[Regina Barber]

Scott Burley, thank you for spacing out with me. I had a great time.

[Burleigh McCoy]

My mind definitely feels spacey after that.

[Scott Detrow]

You know, contemplating the expansion of the universe will do that.

[Regina Barber]

It will. I enjoy it. If you like this episode, please share it with a friend. It really helps our show. And hey, give us a follow on the NPR app or wherever you're listening from so you'll never miss a new episode from us. This episode was Produced by Burleigh McCoy and Kai McNamee. It was edited by Christopher Intagliota and our showrunner, Rebecca Ramirez.

[Burleigh McCoy]

Tyler Jones checked the facts. Robert Rodriguez, Ted Mebane, and Hannah Glovna were the audio engineers. I'm Burleigh McCoy.

[Regina Barber]

And I'm Regina Barber. Thank you for listening to Shortwave, the science podcast from npr. See you Monday.

[Scott Detrow]

I'm floating away.

[Burleigh McCoy]

Accelerating or decelerating?

[Regina Barber]

Decelerating. He stopped.

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