Astronauts, Clean Up Your Outer Space! What in the world is all that junk floating around in Low Earth Orbit? And how in the world can gecko feet possibly help to clean it up? Join Mindy Thomas and Guy Raz as they take us on an out-of-this-world quest, to solve one of the messiest problems in our solar system! It's the latest who, what, when, where, why, how, and WOW in the World!

Astronauts, Clean Up Your Outer Space!

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UNIDENTIFIED MAN #1: Stay seated. Three, two, one, ignition.

UNIDENTIFIED MAN #2: Get ready for an adventure of magnificent proportions.


THE POP UPS: (Singing) I don't know what you've been told, but we're in a golden age - so many discoveries that are jumping off the page. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world.

UNIDENTIFIED MAN #3: With Guy and Mindy.

UNIDENTIFIED MAN #1: We're on our way, Houston.



Excuse me. Is this thing on? I don't think it's on. B-B-B-Bagels, b-b-b-bagels.


THOMAS: Oh, it is on. It's on. Can everyone hear me? Can everyone hear me?


THOMAS: Thank you.

UNIDENTIFIED WOMAN #1: We can hear you.

THOMAS: Thank you. Thank you. Now, astronauts, please take your seats. Sit down. Please take your - sit down.

UNIDENTIFIED MAN #4: There's no chairs.

THOMAS: Sit down, all the way down.

UNIDENTIFIED MAN #5: Or gravity.

THOMAS: OK, OK, then you can float if you need to, all right? Just, I need everyone's attention. OK, thank you. Thank you. Now, you may all be wondering why I brought you here today to the International Space Station. Well, it's been brought to my attention that you have been leaving your space junk all over outer space. And now it's time to clean it up.

UNIDENTIFIED MAN #4: Oh, yeah, right.

UNIDENTIFIED WOMAN #1: It's not even mine.


THOMAS: No, I don't care whose junk it is. It's a mess up here, and it's dangerous. And if we don't clean it up, someone is going to get hurt.



THOMAS: Astronauts, I'm only going to say this once. Clean up your outer space right this minute or no freeze-dried ice cream for dessert.



THOMAS: And I don't want to hear any whining. (Unintelligible).



Hey, Mindy. Who are you yelling at in here? I could hear you all the way from my house.

THOMAS: Oh, hey, Guy Raz. I'm just imagining what I would say to the astronauts on the International Space Station if I had the chance. And it is not going well. Here, pop the top of my head and see for yourself.

RAZ: I still feel weird about doing this, Mindy.

THOMAS: Here, I'll do it for you. Just...


UNIDENTIFIED MAN #4: Get out of here.

THOMAS: Whoa, quick, close it back up before they get out. See what I mean?

RAZ: Yeah, wow, those astronauts are really mad. What's going on?

THOMAS: I know I just asked them to clean up all their scrap metal and junk that's floating around in space. It's a mess up there.

RAZ: You mean, all those bits of old satellites and empty rocket parts and pieces of metal just floating around Earth?

THOMAS: Yeah. It's just this giant junk jumble that's been growing since 1957, which, by the way, is the same year that humans first launched a rocket into space. And that was the rocket that carried the world's first space satellite called Sputnik - still the best name ever.

RAZ: Oh, yeah, that was launched by Russia.

THOMAS: You are a little baby Einstein, Guy Raz. Anywho (ph), ever since then, we humans have been launching more and more and more and more and more rockets and satellites up into space.

RAZ: Mindy, did you happen to investigate just how much junk is even up there?

THOMAS: Sure did. So the last time I counted...

RAZ: You did not count it, Mindy.

THOMAS: OK, so the last time someone else counted - NASA - they found more than 500,000 pieces of space junk, all the size of a marble or larger, just orbiting or circling around the Earth.

RAZ: Wow.

THOMAS: And now there are so many pieces of metal floating up there and orbiting around our planet that it's actually making things dangerous.

RAZ: Dangerous, as in, some of this junk can actually crash into other junk?

THOMAS: Yep. And, in fact, this junk is flying around so fast that it's pretty surprising that there aren't even more accidents and crashes.

RAZ: Yeah, I see your point. And I imagine that this can cause real problems for satellites, like the ones we use to help forecast our weather or the ones that take pictures of Earth.

THOMAS: Yeah. And it could also be dangerous for the human astronauts aboard the International Space Station.

RAZ: Yikes. And I'd imagine that crashes caused by the space junk would probably create even more space junk that would go on to destroy more objects in space, like a chain reaction of junk and disaster.

THOMAS: You know it, Guy Raz. In fact, there's even a name for this crazy catastrophic chain reaction.

RAZ: Really?

THOMAS: Yep. It's known as the Kessler syndrome, and it's named after the NASA scientist Donald J. Kessler who first came up with the idea all the way back in 1978.

RAZ: The Kessler syndrome, a catastrophic chain reaction of junk and disaster. That sounds like - hey, that sounds like you, Mindy.

THOMAS: What? I can't believe you noticed, Guy Raz. Hey, have you ever wondered what it might feel like to fly through all that space junk?

RAZ: Come to think of it, not really.

THOMAS: Well, then you're in luck, my friend, because I have purchased not one, but two space-debris-proof, rubber space flying suits. And I got one just your size.

RAZ: What?

THOMAS: Then I lost it. So I had to go back to the store, and they only had toddler sizes left.

RAZ: No.

THOMAS: So I had to get one of those for you.

RAZ: No.

THOMAS: It's going to be a tight squeeze.

RAZ: No.

THOMAS: But it will be worth it.

RAZ: No.

THOMAS: Here, put this on. Come on, you can do hard things. Just suck in everything you've got. There you go, little buddy.

RAZ: This thing...

THOMAS: Now, just try not to exhale while I jump into my suit.

RAZ: ...Is a little tight.

THOMAS: All set. Ready to go?

RAZ: You promise this is going to protect us?

THOMAS: No, I can't promise you that. But what's a few bumps and bruises, Guy Raz, when you are in the pursuit of science?

RAZ: Yeah, fair enough. OK.

THOMAS: So listen carefully because here's how it's going to work. So first, my carrier pigeon Reggie (ph) is going to fly us up to the upper reaches of the stratosphere. Then, we're going to have to use these rocket launchers on our rubber space to get us into low-Earth orbit. OK?

RAZ: OK, Mindy.

THOMAS: Reggie, slap on your space goggles, you cuckoo old bird. We're ready for takeoff. Guy Raz, let's say the magic words.



THOMAS: OK, now this is the part where Reggie says sayonara. Flip on your rocket boosters, Guy Raz.

RAZ: OK, I'm assuming it's this red button here.

THOMAS: Yep, that's the one.

RAZ: (Screaming).

THOMAS: (Laughing) This is so awesome. Can you believe it? We're flying through space, Guy Raz.

RAZ: Mindy, I think we're traveling at 17,000 miles an hour.

THOMAS: That sounds about right. Wow, rocket straight ahead, pull the plugs, watch your head.

RAZ: Just missed it. But, wow, this is nuts. There's so much junk up here.

THOMAS: I know, right? I told you. Whoa, watch out, you're going to deflect some loose screws.

RAZ: I think they're going to hit us.

THOMAS: Brace for impact.

RAZ: Mindy, I think I get the point. Can we rocket back to Earth now?

THOMAS: Sorry, I can't hear you, Guy Raz. I'm already halfway back to Earth.

RAZ: Oh, brother, rocket boosters on, back to Earth. What? Oh, no.

THOMAS: Oh, hey, Guy Raz. Where did you come from?

RAZ: (Screaming).

THOMAS: Man, that was wild.

RAZ: You were right, Mindy. It's a veritable junkyard up there in space.

THOMAS: So now do you see why I wanted to get the astronauts to help clean it up?

RAZ: Yeah, but it's going to be virtually impossible for the astronauts to do it alone. I mean, they're going to need some help.

THOMAS: You better believe it, Guy Raz.

RAZ: So then, why don't we just invent, like, a giant space net for them?

THOMAS: Well, scientists have actually thought of that. But it wouldn't work because it would be so hard to capture all of that junk and keep it from floating out of the net.

RAZ: And, of course, I guess a vacuum cleaner wouldn't work because it needs the air pressure here on Earth to suck things in.

THOMAS: Yep. And in space, there isn't enough air pressure to get the vacuum cleaner to suck stuff up.

RAZ: So what can we do? I mean, how can we solve this problem of space junk?

THOMAS: Well, the good news, Guy Raz, is that some super inventive scientists and engineers are already on the case.

RAZ: Phew, that's a relief. So what's their solution?

THOMAS: Oh, geckos.

RAZ: Geckos.

THOMAS: Well, not whole geckos, just their feet.

RAZ: Now, I did buy my car insurance from a gecko, but I'm not sure he'd survive in outer space.

THOMAS: Wait, did you really buy your car insurance from a gecko?

RAZ: You were the one to recommend him to me. I mean, you said he'd give me a discount.

THOMAS: I didn't think it would actually work. Anywho, back to the gecko feet.

RAZ: I'm with you, I think.

THOMAS: So you know how when you chase a gecko up a wall or a sliding glass door?

RAZ: No, I've never tried that.

THOMAS: Well, I've tried it. And let me tell you, it's not as easy as it looks.


THOMAS: They scale up super smooth walls like nobody's beeswax and then laugh at you as they hang upside down by the tips of their toes.

RAZ: Right. And they're able to do this because they have super-special sticky toes, right?

THOMAS: Well, this is where it gets interesting. So if you were to look at the bottoms of their toes under a microscope, you'd notice that they're actually covered in teeny, tiny microscopic hairs called setae.

RAZ: Interesting - but how are hairy gecko toes going to help clean up all that space junk in low-Earth orbit?

THOMAS: Well, the story begins with an engineering professor at Stanford University in California named Mark Cutkosky. And he came up with this crazy idea, which he published in the journal Science Robotics.

RAZ: What was the idea?

THOMAS: The idea was that by using something called biomimicry...

RAZ: Biomimicry - that means using animals and plants as the inspiration for new technology, for inventing cool new things.

THOMAS: Exactly. So in this case, that animal would be the gecko.

RAZ: And the gecko's sticky feet.

THOMAS: You're picking up what I'm putting down, Guy Raz. So Professor Cutkosky and his team designed a robot that is actually a giant gripper.

RAZ: Like a big robot hand?

THOMAS: Yeah, kind of, and the bottom of it is covered in thousands of tiny bristles to mimic or copy the setae hairs on the gecko's feet.

RAZ: Wow.

THOMAS: And what's really crazy is that each tiny bristle is 10 times thinner than a human hair.

RAZ: But how do these tiny hairs on the gecko feet and the robot help to create a sticky effect?

THOMAS: Well, on both the gecko and the robot, the hairs, or bristles, work together to create a special kind of sticky electric force.

RAZ: Wait a minute. Are you referring to the Van der Waals force?

THOMAS: I knew this would excite you.

RAZ: So there are atoms or teeny, tiny little balls of material which, to be clear, we cannot see with our own eyes. And they're on the hairs of the robot hand and the gecko. And those atoms stick to the other atoms on the space junk.

THOMAS: That is a complicated phenomenon. But when it works, it can create a really tight, sticky bond between two things.

RAZ: Kind of like a friendship.

THOMAS: Yeah, just like you and me.

RAZ: I get it.

THOMAS: Yeah, and the tiny bristles are put on little pads that are attached to the robot, so it's kind of like a little robot hand or foot that the astronauts can hold onto and control.

RAZ: Wow. And so that's how it's able to grab onto the space junk?

THOMAS: You got it, just like a gecko can stick and unstick its feet to walk up a wall.

RAZ: And this way, the robot can grab the space trash, move it and then, I guess, let it go.

THOMAS: Pretty cool, huh?

RAZ: Yeah, I'll say.

THOMAS: And Professor Cutkosky and his team are designing this robot to be able to stick to and capture the biggest and most dangerous space junk up there.

RAZ: But, I mean, how big and strong will these robots be? Because, I mean, space junk can be huge. Some space junk is the size of trucks just floating around up there. I mean, it's pretty heavy garbage.

THOMAS: Well, that's the thing. Because there's so little gravity in space, really heavy things, like broken satellites or spacecrafts or space minivans aren't actually heavy at all. It's a little bit like when you float in water and you feel a lot lighter.

RAZ: Yeah. So the astronauts that you were scolding in your imagination actually might be able to clean up some of this junk.

THOMAS: That's what I was trying to tell them. These astronauts would be able to take hand-held robots with sticky pads and stick them to pieces of space trash, move it and then unstick it.

RAZ: Yeah, but where would they put it, Mindy? I mean, it's not like there are dumpsters floating around in space.

THOMAS: Oh, this is crazy. So they would push the space trash back towards the Earth, which means that, as it came back flying towards the Earth, the speed would create so much heat that the junk would naturally burn up before it even reached our planet.

RAZ: Wow.

THOMAS: Or they could even take some of it and put it inside a special spaceship to be recycled.

RAZ: So by cleaning up this giant garbage pile floating around in space, we would actually be making space a little bit safer.

THOMAS: Yep. And this same gecko-foot inspired technology could also be used to help us regular humans here on Earth.

RAZ: Really? How so?

THOMAS: Well, some medical researchers are thinking that maybe they could use it to create a special kind of tape that could be used in place of stitches or even a pair of gloves that could give a person the ability to climb like Spiderman.

RAZ: Wow, I will never look at geckos the same again, Mindy.

THOMAS: Me neither, Guy Raz. I'll never look at any animals' superpowers the same way again.

RAZ: You know what? That reminds me - speaking of all this biomimicry and animal superpowers, did you know that Velcro was inspired by the tiny hooks or burrs from bushes and plants that stick to our clothes?

THOMAS: No way, prickly plants are nature's Velcro? Well, can you guess why researchers are studying how schools of fish swim together without bumping into one another?

RAZ: I wonder if that might have something to do with wanting to figure out how to do the same thing with cars, with driverless cars, you know, to keep them from crashing.


RAZ: And hey, have you heard of the UltraCane?

THOMAS: The edible peppermint-candy walking cane that people can suck on when they're not using it to help them walk.

RAZ: What? No, no, no, no, it's a cane for the blind which uses echolocation or sound waves to tell the person using it that they're close to an object, like a wall. It's the same technique used by dolphins and bats.

THOMAS: Man, it's so cool to think that biomimicry of the smallest creatures could solve some of the biggest problems in our universe.

RAZ: So about those astronauts in your head who are trying to get out of cleaning up their space junk...

THOMAS: Oh, yeah, so you want to break the news to them?

RAZ: I don't know if my insurance covers climbing into your imagination, Mindy.

THOMAS: It does if you bring your gecko insurance salesman.

RAZ: OK, here we go.

THOMAS: Easy does it.

RAZ: Do I just climb inside?

THOMAS: Take your shoes off first. Got it - you got it. Just climb right inside. Yup.

RAZ: I'm in here. Now what, Mindy?

THOMAS: OK, now take the podium, and show them who's boss.

RAZ: Astronauts, hello.

UNIDENTIFIED MAN #6: Who's this guy?

RAZ: You're going to have to clean up your space junk.

UNIDENTIFIED MAN #7: I'm not doing it.



UNIDENTIFIED MAN #7: I'm an adult.


THOMAS: Now tell them the good news.

RAZ: But thanks to the common reptile known as the gecko, cleaning up outer space is about to get a lot more fun.


THE POP UPS: (Singing) Wow in the world.

THOMAS: Hi, what's your name?

SAMUEL: My name is Samuel (ph).

THOMAS: Samuel, how would you clean up all of the junk in space?

SAMUEL: I would send Wall-E wall up there (laughter).

THOMAS: So your solution is Wall-E.



THOMAS: What's your name?

EVAN: My name is Evan (ph).

THOMAS: Evan, how would you clean up outer space?

EVAN: I would build a spaceship, and it would have a thing that collects the junk and reuses it.

THOMAS: Hey, what's your name?

DANIEL: Daniel (ph).

THOMAS: Daniel, how would you clean up all the space trash?

DANIEL: With, like, a dump truck scooper thing - and throw it towards Mars.

THOMAS: A space dump truck.


THOMAS: What's your name?

SAMANTHA: Samantha (ph).

THOMAS: Samantha, how would you clean up all of the trash in outer space?

SAMANTHA: Like, in the really far future, we could maybe have a tour-of-space-type bus so people could see space, but it would also be doing good for the environment and getting all the space junk. And then at the end, it would just burn all the trash.

THOMAS: Samuel, what do you think the punishment should be for astronauts who don't clean up their outer space?

SAMUEL: It's "Survivor" but in space. Who will be voted off first?

THOMAS: Who will be voted off outer space?

SAMUEL: I wasn't thinking about that.


THOMAS: So Daniel, what would you do with all of that space junk if they dumped it all on your front yard?

DANIEL: I would burn it.

THOMAS: What about you, Evan?

EVAN: I would build another spaceship.

THOMAS: Samantha?

SAMANTHA: Space-junk artwork because I've seen people do that with marine debris.

THOMAS: What are your names?

MELANIE: I'm Melanie (ph).

ABBY: And I'm Abby (ph).

MELANIE AND ABBY: We would make a fort.

ABBY: A fort. Like...

MELANIE: It'd be huge.

ABBY: Exactly, like...

MELANIE: And all of our friends could hang out there.

ABBY: Yes.

MELANIE: It'd be, like, our own little personal house.

ABBY: Just imagine it, like, in its glory.

THOMAS: You guys, what if we all went up to outer space and just built the fort up there?

ABBY: That'd be so cool.

MELANIE: We should.

SAMANTHA: That'd be awesome.

SAMUEL: On the moon.


SAMANTHA: Yeah, that'd be awesome.

EVAN: Where would we build it on? There's no little islands in space.

SAMUEL: Well...

THOMAS: Why so many questions, Evan?

SAMUEL: Yeah, Evan.

DANIEL: Right.

THOMAS: Thanks, guys.




SAMANTHA: Thank you.

SAMUEL: (Singing) Bye.



SAMUEL: Let's do another one.


THE POP UPS: (Singing) Wow in the world.

THOMAS: Hey, thanks so much for listening to WOW IN THE WORLD this week.

RAZ: And parents, if you want to continue the conversation with your kids, we've posted some questions about this episode at our website,

THOMAS: And while you're there, you can find links to some of the sources we used to tell our stories this week.

RAZ: Also, we love hearing from you. You can write us at

THOMAS: Our show is produced by Jed Anderson. Say hello, Jed.

JED ANDERSON: Yello (ph).

RAZ: Our theme song, "Wow In The World," was written and performed by The Pop Ups. Check them out at

THOMAS: Big thanks to the kids you heard in today's episode. Sam, Daniel, Evan, Samantha, Abby and Melanie, thank you so much for sharing your ideas with us. Now, go clean your rooms. Also, we love hearing what's been wowing you. For a chance to be featured on an upcoming Thursday episode, have your grown-ups help you share something that's recently wowed your world by dialing 1-888-7-WOW-WOW. Thanks again for listening, subscribing and telling your friends about our show. We'll be back for a brand new Thursday edition. In the meantime, go forth and find your own wow in the world.


THE POP UPS: (Singing) Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world. Wow in the world.

UNIDENTIFIED CHILD: WOW IN THE WORLD was made by Tinkercast and sent to you by NPR.


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