Artemis Program Faces More Delays

IRA FLATOW: This is Science Friday. I’m Ira Flatow. Later in the hour, what’s up with the THC gummies at the gas station? And how genetics research could help bring back the iconic American chestnut tree.

But first, NASA administrator Jared Isaacman announced today that the agency is rescheduling its mission of putting astronauts back on the moon, the long-term goal of the Artemis program, rescheduling it to at least 2028. The revised plan would add additional time and another test flight into a series of missions that has already faced setbacks, including this week, when the agency had to roll the rocket for the Artemis II test flight, scheduled for this spring, had to roll it back to the garage.

This is the mission aimed at sending four astronauts on a 10-day voyage around the moon. It would be, if and when it happens, the first crewed mission to the moon in more than 50 years. Here to update us on Artemis II and other science news of the week is Maggie Koerth, climate and weather editor at CNN. Maggie, welcome back.

MAGGIE KOERTH: Thank you for having me.

IRA FLATOW: OK, so what’s the delay for this time?

MAGGIE KOERTH: OK, so [LAUGHS] Tuesday, the astronauts from Artemis II were sitting in the State of the Union. Wednesday, their spaceship was being rolled back into the garage because they were–

IRA FLATOW: No connection there. We’re not implying a connection, right?

MAGGIE KOERTH: No, we’re not implying a connection.

IRA FLATOW: OK.

MAGGIE KOERTH: Just to name the highs and lows of life as an astronaut.

IRA FLATOW: Right.

MAGGIE KOERTH: The spacecraft is having problems getting helium to flow within it. This is in contrast to back on February 2, when Artemis II launch got scrapped because they were having a helium leak. And now the soonest it’s going to be able to get up is in April.

IRA FLATOW: Wow. Wow. And so this is really highly anticipated. And the goal of the voyage? Remind us again.

MAGGIE KOERTH: The goal of the voyage is to prove that NASA’s space launch system rocket and the Orion spacecraft can really do the performance they’re supposed to do. And these are the vessels that are supposed to eventually land us on the moon again and establish permanent bases there.

IRA FLATOW: Let’s speak of rockets again, because there’s a new study that looked at metal pollution from rockets reentering the atmosphere. Tell me about that, please.

MAGGIE KOERTH: Yeah. So back in the ’80s, we worried about aerosol hairspray destroying the ozone layer. Now we have cool, new sci-fi threats to our planet’s atmospheric shield, and that is dead rocket parts. It turns out that all the aluminum and lithium and these other metals that make up rockets and satellites and space junk, in general, can end up being released into the atmosphere as that junk breaks apart during re-entry.

This recent paper was the first documentation of these metals being released. It happened on February 19 of 2025, when SpaceX launched one of its routine missions to add more satellites to Starlink. So this Falcon 9 rocket’s upper stage falls back to Earth, disintegrates on its way down, and researchers were able to use lasers to trace this cloud of lithium trailing across Europe, about 10 times more lithium than you’d find naturally.

IRA FLATOW: But we don’t what kind of consequences all of this will lead to, do we?

MAGGIE KOERTH: Not yet, no. What we really need is a lot more research. We have way more space junk than we used to. We have these satellite swarms, like Starlink, that are adding tons more up there all the time. And none of those satellites are meant to last for a huge amount of time. I think Starlink is like five-year lifespan, and so you’re getting more rockets going up, also, to replace them. So getting a handle on just how much damage all of this could cause is pretty important.

IRA FLATOW: Right, right. All right, now for something totally different, as they used to say.

MAGGIE KOERTH: What do you mean?

IRA FLATOW: I’ve read about that one in 200 men in the world are related to Genghis Khan.

MAGGIE KOERTH: [CHUCKLES]

IRA FLATOW: Right? Now, where did that idea come from in the first place?

MAGGIE KOERTH: It comes from a 2003 paper that was tracking a Y-chromosome lineage that’s now common in people who live in what was once the Mongol Empire. That lineage is called C3. And researchers back in 2003 found evidence that it had originated in Mongolia about 1,000 years ago. It’s not for certain that it was Genghis Khan’s, but they were kind of like drawing these inferences along the way.

IRA FLATOW: Right. But now, the news is that there’s a new study out that debunks this, right?

MAGGIE KOERTH: Sort of. So–

IRA FLATOW: Sort of.

MAGGIE KOERTH: Sort of. It narrows it, we’ll say. So this new one was done on three dead bodies. And what they’re finding is that these bodies have a far rarer subset of C3. So instead of this big family that encompasses tons and tons of people, it’s actually maybe a more narrow sliver. And that ancient warlord might not be quite as prolific as we’ve given him credit for.

IRA FLATOW: Hmm. And how did the researchers figure this out that it wasn’t the case?

MAGGIE KOERTH: Well, so they went for bodies that are in mausoleums that have been traditionally attributed to the descendants of Genghis Khan’s oldest legitimate son, Jochi. So these skeletons are probably not Jochi himself because the timing isn’t right for when they died. But they all three share a paternal lineage that’s passed from father to son in the Y-chromosome. And that lineage is a subset. It’s that little subset of C3.

IRA FLATOW: Hmm. I’m having visions of Raiders of the Lost Ark going through all these skeletons.

MAGGIE KOERTH: Right? Yeah. I know. There’s definitely some “oh, no, the curse” vibes, but–

[LAUGHTER]

IRA FLATOW: Let’s go to some other news. And this may be something even more astounding. And that’s the brains of super-agers may have a special ability? A superpower, Maggie?

MAGGIE KOERTH: Yeah. So the scientists looked at brains from adults from across the age spectrum and found that a handful of people who are older than 80 and who are still making memories really well into their elderly years, they’re not only making new neurons, but they’re making them at twice the rate of normal people half their age.

IRA FLATOW: But how? Didn’t we learn in grammar school that the brain doesn’t make any new neurons?

MAGGIE KOERTH: Well, that is what we learned in grammar school for most of us who went to grammar school in the 20th century.

IRA FLATOW: [CHUCKLES]

MAGGIE KOERTH: Over the past two decades, though, there’s been a growing body of evidence suggesting that’s not necessarily the case. There’s pretty good data to show that both mice and other species of primates grow new neurons in parts of the brain connected to memory while they are adults.

It is still, however, a big issue of debate about whether humans do this, too. And that is because we have to wait until people are dead and look at their brains. And there’s not really enough of these super-agers’ brains in the study to make the findings statistically significant, according to reporting at Nature.

IRA FLATOW: Right, right. But where do the neurons come from?

MAGGIE KOERTH: The scientists looked at genetic markers in the brains. It’s like this new technique. And that helped them find both neural stem cells and neuron cells at other stages of development, kind of like being able to see the babies, the kids, and the teenagers. And so they were able to see how these older adult brains that came from people who had really good memories still into their 80s were different.

IRA FLATOW: All right, let’s wrap up with some animal news. Everybody likes animal news. First up, how caterpillars fool ants into taking care of them. Maggie, what’s going on here?

MAGGIE KOERTH: Well, that cross-species cuckoo behavior, essentially. They’re getting the ants to carry them back to their nests, feed them, care for them, protect them. In fact, the only way these species survive caterpillar childhood is under the care of ants.

IRA FLATOW: Wow, to be a caterpillar. That sounds pretty cushy. I mean, how are they tricking the ants into doing this?

MAGGIE KOERTH: So these are ants who have queens, who make rhythmic sounds by rubbing these hard parts of their abdomens together to get a vibration. It’s like that musical instrument from grade school with the stick and the ribbed wooden tube. And it’s kind of like, brrr, you know?

IRA FLATOW: Right.

MAGGIE KOERTH: So somehow, these caterpillars– which do not have any hard parts to rub, I should clarify– are making the same sounds. And no one knows exactly how. So to look at this, scientists collected a bunch of species of ants and a bunch of species of caterpillars, and they recorded the vibrations they made. And all of these species were able to do these kind of consistent beats, like a metronome– bop, bop, bop, bop.

But the caterpillars that needed the ants to survive could do something a little more spectacular. They could keep up a kind of beat called a double meter. So think of it more like bum-bum, or bum-boom. And the ants who cared for them could do that, too. So it seems like they’re kind of replicating the sounds that these ants make and turning it into a little bit of a call for help.

IRA FLATOW: Huh. Speaking of carrying a tune, I know there’s a new study out about how this beautiful sound happens.

[HORSE WHINNYING]

A horse’s whinny, right, Maggie? How do they make that sound?

MAGGIE KOERTH: Of course. Of course. Scientists were trying to figure this out because horses make sounds at different pitches than you would expect them to. So, like, a larynx is just a tube. And it’s got these kind of folds. That was what we call vocal cords. And vibrating air over the vocal cords is how you get sounds. And the bigger the animal, the bigger the larynx, the lower the sounds. That’s what you’d expect. But horses can do high notes, too, in those whinnies, right?

IRA FLATOW: Right.

MAGGIE KOERTH: And people didn’t quite understand how that worked. And the first time they tried to study this, they were using endoscopic cameras to watch live horses talk. And they would see the air move through the tube of the larynx and over the folds, and just like normal, like you’d expect, on the low sounds. And then the horses would make high sounds, and nothing would move. It would just be completely still vocal cords.

IRA FLATOW: Wow. And so they figured out that the horse is actually making two sounds at once?

MAGGIE KOERTH: Yep. They got a hold of horse larynxes, and they forced compressed air through the larynx. First saw the same thing again, but they started to think that the horses were using the larynx tube itself as a whistle. So to prove that, they tried helium, instead of air. And that works because a sound made by plucking a string or moving a vocal cord will sound the same in helium or air, but a whistle is going to come out higher-pitched. And sure enough, when you did that, extra-high-pitched whistles.

IRA FLATOW: Wow. How unique is this? This ability to whistle and sing at the same time.

MAGGIE KOERTH: It’s not entirely unheard of. Rodents can do it, too. But this is the first time that we have seen a big animal, like a horse, that can do it.

IRA FLATOW: Well, I’ve certainly stifled my desire to imitate Mr. Ed. So I want to thank you, Maggie, for–

MAGGIE KOERTH: [LAUGHS]

IRA FLATOW: –taking the time to be with us today on that one.

MAGGIE KOERTH: You’re welcome. Good luck.

IRA FLATOW: Thank you. Maggie Koerth is a climate and weather editor at CNN.

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