Moment Of Um

How do ping-pong balls bounce so high?

13 Jan 2025

Contributed by Lukas

Ping pong is a super fun game. It’s like miniature tennis, where people use paddles to make balls fly across a table., and sometimes way, way up in ...

How does gasoline turn into exhaust?

10 Jan 2025

Contributed by Lukas

Lots of cars, trucks and buses are powered by gasoline. You put the gasoline in a little hole on the side of the vehicle, it powers the engine and the...

What happens in our bodies when we are sick?

09 Jan 2025

Contributed by Lukas

Let’s say you wake up on a Tuesday morning feeling fine and fresh. But by the end of the night your throat hurts, you’re coughing, and there’s s...

Why do some trees grow taller than others?

08 Jan 2025

Contributed by Lukas

There are all different kinds of trees in the world, from towering redwoods to tiny willow trees smaller than an action figure. Why are there so many ...

Why are peaches and some other fruits fuzzy?

07 Jan 2025

Contributed by Lukas

Have you ever picked up a peach in the supermarket and noticed that its skin is covered in soft fuzz? What’s that about? Should we be taking our pea...

How were black holes first discovered?

06 Jan 2025

Contributed by Lukas

Black holes are mysterious. They are so dense that no light can escape them, which makes them super hard to find! So how did we discover the first bla...

How do records work?

20 Dec 2024

Contributed by Lukas

Records are big flat discs with circular lines on them that you can use to play music. But how does a record work, anyway? We asked audio engineer Jos...

Do airplanes have a speed limit?

19 Dec 2024

Contributed by Lukas

Airplanes fly high in the sky and at super fast speeds. But is there a limit to how fast they’re allowed to fly? You know, in the way cars have spee...

How do stethoscopes work?

18 Dec 2024

Contributed by Lukas

Have you ever been to the doctor and had them listen to your body with a stethoscope? It’s that funny looking thing that looks like a long rubbery t...

How many times does our heart beat a day?

17 Dec 2024

Contributed by Lukas

Most of us know that we have a heart. We know that it beats - sometimes faster, sometimes slower. But just how many times does it beat in a day? We as...

How do sinkholes form?

16 Dec 2024

Contributed by Lukas

Have you ever seen a sinkhole? These are spots in the Earth’s surface where the ground has collapsed and formed a hole. Sometimes they can be more t...

What would happen if I went inside a black hole?

13 Dec 2024

Contributed by Lukas

Black holes are super dense spots in space. They have so much gravity that when something falls into a black hole, it can’t escape. We asked UCLA as...

How do 3D glasses work?

12 Dec 2024

Contributed by Lukas

3D glasses. Those little paper spectacles with one red lens and one blue. Put ’em on, and suddenly, POW! Images seem to leap right off the screen! D...

How do vocal cords work?

11 Dec 2024

Contributed by Lukas

Vocal cords are magical things. They let us speak, sing, squawk and scream. But what are vocal cords and how do they do all that? We asked pediatricia...

How does hair dye work?

10 Dec 2024

Contributed by Lukas

If you could turn your hair any color in the world… what color would you choose?! Sapphire blue, hot pink, lime green, neon orange?? There are dyes ...

How are bricks made?

09 Dec 2024

Contributed by Lukas

Bricks are all around us: in walls, sidewalks, park benches, and more. How are these bodacious blocks made, and what makes them different colors?  We...

When did people start using utensils?

06 Dec 2024

Contributed by Lukas

People around the world eat with a variety of utensils like forks, chopsticks, and sporks. But what did people do before silverware was invented? We a...

How do our clothes get dirty?

05 Dec 2024

Contributed by Lukas

Clothes are FUN. We strut our stuff in them. Laugh and play in them. Sometimes we love one article of clothing so much, we never want to take it off! ...

Why does salt make you thirsty?

04 Dec 2024

Contributed by Lukas

Have you ever noticed that when you eat something salty, you feel extra thirsty for a while afterwards? Ever wondered why? Turns out, scientists are w...

Why does bread have holes?

03 Dec 2024

Contributed by Lukas

Bread! It’s good stuff, no matter how you slice it. But why do slices of bread have holes in them? Are there bread moles who tunnel through baguette...

How do people get warts?

02 Dec 2024

Contributed by Lukas

Warts are small bumps that can show up on our skin, especially on our hands, knees, or elbows. What are they? Where do they come from? We asked Dr. Ka...

How does a platypus make its venom?

29 Nov 2024

Contributed by Lukas

Platypuses seem like they were put together from other animal’s spare parts. They’ve got a bill like a duck, a flat tail like a beaver, and…veno...

How did the peregrine falcon get its name?

28 Nov 2024

Contributed by Lukas

Peregrine falcons are the fastest animals on earth. They’re the super sonic jets of the animal kingdom! So what does the word “peregrine” mean a...

Why don’t mountain lions have manes?

27 Nov 2024

Contributed by Lukas

When you picture a lion, what do you see? If you thought of a big fluffy mane, you’re not alone! But how come mountain lions don’t have manes? We ...

Do birds cough or sneeze?

26 Nov 2024

Contributed by Lukas

Birds have a lot going on. They fly, chirp, sing, make nests, lay eggs. But can they cough or sneeze? We asked biologist Imogene Cancellare to help us...

How do bears make their dens?

25 Nov 2024

Contributed by Lukas

Most bear species spend at least part of the winter season snoozing – a.k.a. hibernating! To prepare for that extended nap sesh, bears snuggle up in...

Why do we have friends?

22 Nov 2024

Contributed by Lukas

Friends rule! The best ones are those that are always there to help you out, embark on a strange adventure,  make you laugh so hard you cry and appr...

What is the strongest glue?

21 Nov 2024

Contributed by Lukas

Most of us have used a glue stick or Elmer’s, but what about the strongest glue in the WORLD? We got a fantastic question from a couple of listeners...

Do penguins sit down?

20 Nov 2024

Contributed by Lukas

Did you know there are 18 species of penguin in the world? Each species has its own differences and quirks, but one thing all penguins have in common ...

What causes solar flares?

19 Nov 2024

Contributed by Lukas

Listener Graham wanted to know what solar flares are and what causes them, so we reached out to NASA Heliophysicist Nicola Fox to help us figure out w...

How do trumpets make that bbbbrrrrrrr sound?

18 Nov 2024

Contributed by Lukas

Did you know that trumpets are the oldest brass instruments? Orchestras rely on them to play the highest notes in the brass section! But how do they m...

Is rainwater safe to drink?

15 Nov 2024

Contributed by Lukas

On Earth, water gets evaporated by the sun from the planet’s surface, and then drops back down from the clouds when it rains. That’s a great sourc...

What's the smallest unit of measurement?

14 Nov 2024

Contributed by Lukas

Let’s say you want to measure something really, really, really tiny. How do you do that? With inches? Centimeters? Millimeters? What if it’s so ti...

How do stars form black holes?

13 Nov 2024

Contributed by Lukas

Black holes are areas in outer space that have gravity so strong that not even light can escape its pull! Some black holes are formed from stars…so ...

Why do daddy long legs have super long legs?

12 Nov 2024

Contributed by Lukas

Whether you’re a fan or not, one thing is for sure - most of us have had an encounter with a daddy long legs. They’ve got super duper long legs, a...

How do fireworks explode?

11 Nov 2024

Contributed by Lukas

Fireworks are loud and exciting! You light a fuse and the firework rockets up into the air, and then BLAM! It explodes into colorful, sparkling bouque...

How do batteries work?

08 Nov 2024

Contributed by Lukas

Batteries power lots of stuff that people use everyday, like cellphones, toys and laptop computers. Some batteries can even be recharged after they ru...

Why do we rub our eyes when we're tired?

07 Nov 2024

Contributed by Lukas

It seems universal that when a person - old or young - is tired, they rub their eyes. It’s even a way that babies communicate to their adults that t...

How do lightbulbs work?

06 Nov 2024

Contributed by Lukas

Have you ever turned on a light and wondered, “How does that thing light up, anyway?” Us, too! We asked Tim Pula of the Smithsonian’s National M...

Why do ostriches stick their heads in the ground?

05 Nov 2024

Contributed by Lukas

Ostriches are super neat! They’re the world’s heaviest birds, and they lay the largest eggs of any bird on Earth. They grow up to 8 feet tall, and...

How does anesthesia work?

04 Nov 2024

Contributed by Lukas

Sometimes, doctors use something called anesthesia to help them treat patients. Anesthesia can be different substances, but they all prevent our bodie...

Why do we need belly buttons?

01 Nov 2024

Contributed by Lukas

We all have a belly button. Right there, in the middle of our belly, there’s a nub. Some go in, some stick out, but what exactly are they for? We as...

What produces eye gunk when we sleep?

31 Oct 2024

Contributed by Lukas

Have you ever woken up in the morning with the corners of your eyes filled with crud? Sleepy sand? Eye goblins? Dozy dust? Bed boogers? Why do our eye...

How does bug spray work?

30 Oct 2024

Contributed by Lukas

Bug spray helps us keep mosquitoes and other insects away. But how does it work? We asked insect expert Meredith Cenzer to help us find the answer.Got...

Why do we itch?

29 Oct 2024

Contributed by Lukas

A mosquito bites you. Your grandma knits you a scratchy blanket. Your friend tickles you with a feathery cat toy. What do all of these things have in ...

What are antibiotics and probiotics?

28 Oct 2024

Contributed by Lukas

Antibiotics are a kind of medicine that a doctor might give you to help you fight off an infection. But there are also things called probiotics in foo...

How do music boxes work?

25 Oct 2024

Contributed by Lukas

Music boxes are hand-cranked toys that play a tinkly little tune. How do they make their music? We asked music box maker Richard Upchurch to help us f...

Why do pugs have such scrunched faces?

24 Oct 2024

Contributed by Lukas

Pugs! They’re adorable! The internet loves them for their sassy personalities and squishy faces. But how did the pug’s face get so smushed? Why ar...

How do Magic 8-balls work?

23 Oct 2024

Contributed by Lukas

Have you ever played with a Magic 8-Ball? They’re black and white toy balls – but with a twist! People ask the Magic 8-Ball a question, shake it, ...

How and why do we produce saliva?

22 Oct 2024

Contributed by Lukas

Our mouths have a lot going on. They have teeth and a tongue and they help us talk and eat. But what about saliva? It seems important, right? How do o...

How is flannel made?

21 Oct 2024

Contributed by Lukas

Flannel is a soft, comfy fabric used to make shirts, cozy winter bed sheets and all kinds of other stuff. But how is it made?  We asked fabric expert...

Why do irons have to be hot to de-wrinkle things?

18 Oct 2024

Contributed by Lukas

A volcano forms when the hot melted rock deep under the Earth’s crust bubbles to the surface and breaks through. Sometimes, a volcano will go from a...

Why didn't sharks go extinct like dinosaurs?

17 Oct 2024

Contributed by Lukas

If sharks were around in the time of dinosaurs, how are they still here today when dinosaurs have gone extinct? Were some just really, really good at ...

Why do volcanoes go dormant?

16 Oct 2024

Contributed by Lukas

A volcano forms when the hot melted rock deep under the Earth’s crust bubbles to the surface and breaks through. Sometimes, a volcano will go from a...

What is the flavor of root beer?

15 Oct 2024

Contributed by Lukas

A lot of people like root beer! But it’s kind of hard to describe, right? It’s really got a unique taste. We asked Ashley Rose-Young, a historian ...

How does your body make a fever?

14 Oct 2024

Contributed by Lukas

Our body has lots of ways to fight off the germs that make us sick. One of those ways is to crank up our internal temperature to make it too hot for h...

How do QR codes work?

11 Oct 2024

Contributed by Lukas

QR codes are little black-and-white squares that you might have seen on food packages, movie tickets, restaurant menus, and lots of other places. You ...

How do solar panels work?

10 Oct 2024

Contributed by Lukas

Solar panels absorb light from the sun and turn it into electricity. They can power everything from a calculator to a whole country! How does this sun...

How do 3D printers work?

09 Oct 2024

Contributed by Lukas

3D printers are pretty awesome. Unlike the machines that print pictures or words on paper, 3D printers can create things you can hold in your hand –...

What makes a computer a computer?

08 Oct 2024

Contributed by Lukas

Computers are awesome machines. They help us do so many things – from looking up facts to watching hilarious videos. But what exactly makes a comput...

How are computers programmed with ones and zeros?

07 Oct 2024

Contributed by Lukas

Computers can do all sorts of amazing things, from solving complicated math problems to showing us videos of dancing birds. Computers do all that than...

Is there sound in the universe?

27 Sep 2024

Contributed by Lukas

Our world is full of sound, but what happens when we leave Earth’s atmosphere? Is it true that there’s no sound in space, or are there ways to lis...

Why does dust make us sneeze?

26 Sep 2024

Contributed by Lukas

There are lots of reasons to sneeze - you have a cold, you get a whiff of pepper or someone tickles your nose with a feather! But why is it that dust ...

Do all rocks have iron in them?

25 Sep 2024

Contributed by Lukas

Iron is a metal that we dig out of the ground and use to make everything from kitchen knives to skyscrapers. Most of the iron we use comes out of rock...

Can muscles break like bones do?

24 Sep 2024

Contributed by Lukas

If you’ve ever had the unfortunate experience of breaking a bone, it’s not the most fun. But can muscles break in the same way bones can? One list...

Why do fevers give you chills?

23 Sep 2024

Contributed by Lukas

Sometimes when we get sick, our body reacts by cranking up our internal temperature to make a fever. This helps get rid of invading bacteria or viruse...

Why aren’t hermit crabs born with shells?

20 Sep 2024

Contributed by Lukas

Hermit crabs carry their shells with them wherever they go…but they don’t make their own shells! Unlike other species of crab, hermit crabs use sh...

Why is being right-handed more common?

19 Sep 2024

Contributed by Lukas

Are you left-handed or right-handed? Chances are you’re right handed, because more people are (though if you’re left-handed, that’s cool too!). ...

How do butterflies get their designs?

18 Sep 2024

Contributed by Lukas

There are thousands of species of butterflies, all with unique patterns of color on their wings. How did those designs get there? We asked butterfly c...

Do cats go to the dentist?

17 Sep 2024

Contributed by Lukas

An inevitability of life is that humans have to go to the dentist. Some people love it, some hate it! But taking care of our teeth is super important....

What is lava made of?

16 Sep 2024

Contributed by Lukas

Lava is the red-hot gloop that comes pouring out of an erupting volcano. But what is it made out of? Some sort of supercharged Silly Putty? Volcano gu...

Why do gorillas beat their chests (and why is science so great)?

13 Sep 2024

Contributed by Lukas

It’s impressive to see a gorilla beat its chest. But why do they do it? We’ve tackled this question before, but  there’s a new scientific scoop...

Why are cactuses prickly?

12 Sep 2024

Contributed by Lukas

Lots of plants are smooth to the touch, and some are even soft and feathery like flowers! So why are cactuses prickly and sometimes even painful? We a...

Are bananas radioactive?

11 Sep 2024

Contributed by Lukas

Bananas are a delicious, nutritious fruit! You can pack them in a picnic lunch or bake them into a sweet nutty banana bread. But are bananas radioacti...

What happens when parts of your body fall asleep?

10 Sep 2024

Contributed by Lukas

If you’ve ever stood up quickly and felt a little wobbly and tingly in your legs, you might be familiar with the sensation of having a body part tha...

How heavy is North America?

09 Sep 2024

Contributed by Lukas

You can use a scale to measure how heavy something is…but what if that something is really big? Like, really, REALLY big? Like the WHOLE continent o...

Why are keyboards in QWERTY order?

06 Sep 2024

Contributed by Lukas

Have you ever looked at the keyboard on a phone or computer and wondered why the letters are arranged the way they are? The English alphabet starts wi...

Why do horses need horseshoes?

05 Sep 2024

Contributed by Lukas

You don’t see most horses wearing pants, jackets or hats but one thing is for sure - they’re almost always wearing shoes! You know, those u-shaped...

What is carbonation?

04 Sep 2024

Contributed by Lukas

It’s so satisfying to pour a glass of sparkling water. All those tiny bubbles, popping in rapid succession, creating a soothing fizz. Sparkling drin...

Could a popcorn kernel grow into a popcorn plant?

03 Sep 2024

Contributed by Lukas

If you plant certain seeds in the right condition - a plant or tree might grow. But what happens if you plant a popcorn kernel? Will a bowl of popcorn...

How does the internet work?

02 Sep 2024

Contributed by Lukas

The internet has been around since the 1960s, and since then it has become a huge part of our lives. We use it to look up cool facts, send messages, o...

Where does the metal in meteors come from?

30 Aug 2024

Contributed by Lukas

Outer space is far from empty. There are chunks of space rock zipping around, and occasionally one of them finds its way through our atmosphere to sma...

What are tongues for?

29 Aug 2024

Contributed by Lukas

So there’s this big, bumpy muscle inside of our mouths and we know it’s important and that we have to take great care of it. But what’s it even ...

How does coffee keep you awake?

28 Aug 2024

Contributed by Lukas

Coffee is known for giving people energy. In fact, some say they can’t start their day without coffee! It made us wonder why coffee helps us stay aw...

Why do raspberries have little hairs on them?

27 Aug 2024

Contributed by Lukas

Mammals have hair to help keep warm in the cold, and in some cases - to look awesome! But why do raspberries have those little hairs all over them? Th...

Where does blue raspberry flavor come from?

26 Aug 2024

Contributed by Lukas

There are lots of foods that are blue-raspberry flavored, like candy, popsicles, or fizzy drinks. But there’s no such thing as a blue raspberry…so...

Why do people have common dreams?

23 Aug 2024

Contributed by Lukas

Sometimes people dream about similar things, like losing teeth, being chased by monsters, or forgetting to study for a test. Why are there some kinds ...

Why do we have nightmares?

22 Aug 2024

Contributed by Lukas

Ahhh! There is nothing worse than waking up in the middle of the night after a nightmare.  Your heart is pounding, you’re all sweaty and suddenly y...

How do we know dreams aren’t real?

21 Aug 2024

Contributed by Lukas

Have you ever had a dream that felt so real you thought it actually happened? Our brain can cook up some really vivid images while we sleep, complete ...

What happens to dreams we don’t remember?

20 Aug 2024

Contributed by Lukas

Dreams can be fun, scary or just plain weird. We typically dream for around two hours a night, but we usually don’t remember what we dreamt about. S...

Do animals dream when they hibernate?

19 Aug 2024

Contributed by Lukas

When we dream, sleep becomes storytime. You might see an old friend, go on an adventure or show up to a test without having studied. So when animals h...

How do thermometers work?

16 Aug 2024

Contributed by Lukas

A thermometer is a handy dandy little device that measures temperature. We use them for lots of things, from telling us when we have a fever to making...

How do birds fly?

15 Aug 2024

Contributed by Lukas

Is it the wings? Is it the feathers? Is it how light they are? If you’ve ever wondered why birds can fly, this is the episode for you! We asked orni...

Why do our tummies rumble when we’re hungry?

14 Aug 2024

Contributed by Lukas

Have you ever noticed your tummy sometimes makes a little grumbly rumbly sound when it’s time for a snack? What’s up with that? We asked Dr. Lily ...

How do tattoos stay forever?

13 Aug 2024

Contributed by Lukas

In the United States, you can’t get a tattoo until you’re 18 years old. If that seems unfair, just think about it - it’s permanent! As in…fore...

What is radiation?

12 Aug 2024

Contributed by Lukas

You might have heard the word “radiation” in science class or even in superhero movies. It’s something that we’re often warned about, since to...

How is caffeine added to energy drinks?

09 Aug 2024

Contributed by Lukas

Caffeine is a chemical that occurs naturally in drinks like tea and coffee. It can make you feel wide awake and energetic, so it’s also often added ...

How do sloths sleep upside down without letting go?

08 Aug 2024

Contributed by Lukas

Sloths are really, really good at hanging upside down. They practically make it seem effortless! Why is that? Do they love it? Is the world just more ...

How do octopuses blend in with their surroundings?

07 Aug 2024

Contributed by Lukas

Octopuses are incredible and intelligent ocean creatures. They’ve got talented tentacles, three hearts, and can become almost invisible to predators...

Why do we have nails?

06 Aug 2024

Contributed by Lukas

Nails – we clean them, trim them, paint them, and sometimes even wear fake ones! But why do we have them in the first place? We talked to paleontolo...