NASA Astronauts Return To Earth After Extended Stay On The ISS

FLORA LICHTMAN: This is Science Friday. I’m Flora Lichtman. Later in the hour, we’ll explore how tuberculosis shaped history and why, even though we have a cure, it remains the deadliest infectious disease today.

But first, after 286 days aboard the International Space Station, NASA astronauts Butch Wilmore and Suni Williams finally landed back safely on Earth. They had traveled to the ISS for what was to be an eight-day trip and ended up staying nine months because their Boeing Starliner capsule was having thruster issues.

Here to tell us about their return and other notable stories in science this week is Casey Crownhart, senior climate reporter for the MIT Technology Review. She’s based in New York City. Casey, welcome back to Science Friday.

CASEY CROWNHART: Thanks so much for having me. Always great to be here.

FLORA LICHTMAN: So Butch and Suni are back. Yay! Give us the story.

CASEY CROWNHART: Yeah, finally. It’s been a long wait, for sure.

So these two took off on June 25, 2024, on a mission to test Starliner, a Boeing spacecraft which is designed to transport crew to and from the ISS. Like you mentioned, technical issues kind of messed with the plans a little bit. As it was approaching the ISS, the thrusters stopped working. They managed to dock, but they decided to send Starliner back without crew. And so, basically, it’s been kind of a waiting game to get another spacecraft up there that could take these astronauts home and then crew up to the space station so that it wouldn’t be kind of shorthanded.

FLORA LICHTMAN: It’s amazing to me that they don’t have a backup on the shelf, you know?

[LAUGHTER]

CASEY CROWNHART: Yeah. I mean, I think that it’s one of those things where we could have sent an emergency mission, but they were up there doing work, working on experiments, doing spacewalks. They were really OK. It was obviously a delay, but yeah.

FLORA LICHTMAN: Well, what did they do with their extra time up there?

CASEY CROWNHART: Yeah, so they were helping out with experiments that were going on at the Space Station, fixing equipment. Suni Williams actually set a new record for most time spent spacewalking for a woman, 62 hours over nine spacewalks over her career. So yeah, they kept busy.

FLORA LICHTMAN: I’m sure. Has Boeing given an update on what was wrong with the capsule or their future plans for that program?

CASEY CROWNHART: Yeah, so like we said, there were problems with the thrusters, which is why they decided to send it back uncrewed. They’re continuing to test Starliner over the summer, and the company is still making modifications fixing those issues. We don’t have any news about when another flight would take place. The first one would be uncrewed without any people on it, but NASA hasn’t announced the timeline for that or future missions.

FLORA LICHTMAN: Can we talk about my favorite part of the story? Listen to this clip.

[AUDIO PLAYBACK]

– –will be used to lift the Dragon capsule out of the water and onto the recovery vessel. Wow. We’ve got a cute little pod of dolphins. It wasn’t just one or two.

[END PLAYBACK]

CASEY CROWNHART: Yes, I love this. The astronauts got a great little welcome back to Earth. There was a pod of dolphins hopping around in the water where the capsule splashed down in the Gulf of Mexico before that got lifted back onto the recovery boat. So I thought it was adorable.

FLORA LICHTMAN: Perfect welcome. Perfect welcome wagon for them.

Let’s move on to something that we may have suspected but has now been confirmed. This decade has been quite hot.

CASEY CROWNHART: Yes, a warm one, absolutely. So a new report from the World Meteorological Organization confirms that the past 10 years have been the 10 hottest on record. So that’s over nearly 200 years of record keeping. 2024 was the single warmest year on record. The planet’s surface was about 1.55C warmer than the average during preindustrial times.

FLORA LICHTMAN: This sounds bad, of course, but what is it? What does this mean, exactly?

CASEY CROWNHART: Yeah, it’s, I mean, like you said. We know the planet’s heating up. Greenhouse-gas emissions are causing our climate to change. I think that this is really a signal that we are approaching the place where we really don’t want to be. The Paris agreement is the UN treaty that the world agreed to limit warming to 1.5C. Technically, this means we’ve gone beyond that a little bit in the short term, but it means that we really need to take action on climate change.

FLORA LICHTMAN: Tell us about this story that you all at MIT Tech Review published this week about an organization that’s trying to refreeze a massive glacier.

CASEY CROWNHART: Yes. Today is the inaugural UN World Day for Glaciers. So happy to those who celebrate.

FLORA LICHTMAN: I’m celebrating.

CASEY CROWNHART: Yeah, me too. So my colleague James Temple wrote this great story about an organization founded by scientists from MIT and Dartmouth called the Arete Glacier Initiative. They’ve raised about $5 million in funding to study glaciers.

One of the things about glaciers is that we really don’t understand a lot about how they work and how likely some of them are to kind of collapse and fall into the ocean. One glacier in particular that people may have heard of called the Thwaites Glacier, sometimes called the Doomsday Glacier because this is like a massive, massive amount of ice that if it were to melt and fall into the ocean, it could raise sea levels by more than two feet. And so what this organization is trying to do is study this glacier and others to really understand how likely the worst-case scenarios are and look into potential ways to kind of keep that from happening.

FLORA LICHTMAN: Such as?

CASEY CROWNHART: Yes, so one of the things that they’re looking at is kind of refreezing the glacier to the bedrock below it.

[LAUGHTER]

I know.

FLORA LICHTMAN: This sounds very science fiction.

CASEY CROWNHART: Science fiction-y is exactly the way that I would put it too. It’s absolutely fascinating. But I mean, again, if the Thwaites Glacier were to melt, that would mean two feet of sea level rise, so that would have a massive impact on coastal areas around the world.

So if it does look like that is going to happen, one thing that we could do is basically in a lot of glaciers, there’s water between the ice and the bedrock, and that warm water can basically help the glacier move faster, help it melt faster. And so one thing that these scientists want to look into is if we could basically drill holes into the glacier, stick tubes down there, and let the warm water rise out to basically take away that catalyst for warming and movement.

FLORA LICHTMAN: OK, let’s say the tech could work. There must be legal issues.

CASEY CROWNHART: Yeah, there are a lot of kind of caveats and a lot of roadblocks here, as any scientist who is interested in working on this will tell you. So like you said, putting aside the technical barrier to this plan, which would be very, very technically difficult, there are also complicated legal questions. Antarctica isn’t owned by anyone. It’s subject to all these competing territorial claims. It’s governed by this treaty between dozens of nations. So we would need to figure out who gets to decide this, how it gets basically carried out. There are questions about if this kind of thing would harm polar ecosystems and how we make decisions around that. So there’s a lot to figure out, and that’s just, again, beyond the technical questions.

FLORA LICHTMAN: Tell me about this battery-charging announcement from the Chinese automaker BYD. Is it a big deal?

CASEY CROWNHART: It could be. Big if true, basically. So yeah, Chinese automaker BYD, which is the largest maker of electrified vehicles in the world– if you include both plug-in hybrids and fully electrified vehicles, it’s bigger than Tesla. They announced that they have a platform that can charge an EV battery in just five minutes. So that’s like, I would argue, very comparable to filling up your gas-powered car. They showcase this on an event on Monday evening in China. And I don’t know. It could be really interesting if we’re able to see this kind of super-fast charging technology really work.

FLORA LICHTMAN: Are there downsides to charging a battery this fast?

CASEY CROWNHART: There could be. Fast charging today can degrade batteries more quickly, and so there is potential that this could have an impact on lifetime. We don’t really know a lot of details, but that’s something that I would definitely be looking out for.

FLORA LICHTMAN: OK, drug-resistant deadly fungi. It sounds like scientists may have a new way to treat it.

CASEY CROWNHART: Yes, so people may have heard more about antibacterial resistance. Basically, microbes are really good at kind of evolving ways to get around the ways that we know how to kill them. And so researchers have been looking for new ways to kill fungi because some fungi can cause infections in humans that can be very dangerous and be bad for public health. So researchers found a compound that works in a different way to kill fungi. So, basically, they attack a different part of the cell membrane than how most of our current antifungal medications work. So this could be kind of a new class of drugs that could potentially help someday.

FLORA LICHTMAN: Cool. OK, this one’s for the foodies. There’s news this week about the Neanderthal diet.

CASEY CROWNHART: Yes, so OK, if you’re a little queasy, stay with me. It might be a little gross.

FLORA LICHTMAN: Foodies in quotes.

CASEY CROWNHART: Yes. So scientists have thought for a long time that Neanderthals, our close cousins, were eating a whole lot of meat. They were like hypercarnivores, top of the food chain. Now researchers are saying that there’s a chance that, really, they were eating a whole lot of maggots.

So, basically, one way that we can understand what ancient humans or animals were eating is by looking at their bones. Different ratios of isotopes, or types of chemical elements, versions of chemical elements, can kind of tell a story. And so in the ’90s, researchers revealed that Neanderthals had a lot of nitrogen-15. That’s typically the signature of a high-meat diet. But now researchers are saying that, actually, it could also be a sign that they were eating maggots because maggots eating rotting meat also have a very high concentration of nitrogen-15.

FLORA LICHTMAN: Well, look, I mean, the bug diet is the past but also the future.

CASEY CROWNHART: Could be.

FLORA LICHTMAN: OK, for our last story, we’re turning to an endangered frog and a new attempt to help them. Tell me about it.

CASEY CROWNHART: Yes, so, Darwin’s frogs are little tiny frogs, maybe a couple of inches long. They weigh as much as a few paper clips. Unfortunately, these frogs are very susceptible to this very prevalent amphibian disease that has caused mass die-offs of over 400 amphibian species.

Darwin’s frogs were discovered by Charles Darwin on an island off the coast of Chile, which, up until recently, was kind of a sanctuary for these frogs. But a couple of years ago, researchers detected this fungus there that can cause these really bad mass die-offs.

And so folks from the London Zoo went on a rescue mission to establish a captive breeding program, and they took home a good number of these frogs. And key fact here, that these frogs reproduce in kind of an interesting way. A female will lay eggs and kind of take off, and then the males will stand watch. And then once the young hit the stage where they wiggle around, the dad scoops them up and keeps them in a vocal sack. And so–

FLORA LICHTMAN: Just what?

CASEY CROWNHART: Yeah, it’s, I think, really cute.

FLORA LICHTMAN: They put them in their mouth? There are literally frogs in their throat?

CASEY CROWNHART: Yeah. Yeah. It’s a really convenient way to carry them around.

FLORA LICHTMAN: I love this. I mean, to me, this is like– seahorse dads get a lot of street cred. We always hear about the seahorse dads, but Darwin frog dads doing the most.

CASEY CROWNHART: That’s so true. We should talk more about Darwin frog dads.

And so the big news is that last month, some of the male frogs that were brought back in this London Zoo breeding program were carrying young, and so they spit out about 33 hatchlings last month, each about the size of a pencil eraser.

FLORA LICHTMAN: I love that image. Thank you, Casey.

CASEY CROWNHART: Thank you so much.

FLORA LICHTMAN: Casey Crownhart is a senior climate reporter for the MIT Technology Review.

Copyright © 2025 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/