What would happen if you dropped a feather in space?

We’re heading to space, and dropping a feather in a few different places to see what happens!


In space, will a feather stay still? Fall down? Float away? Turns out, the answer depends on where you are! But one thing affects your feather no matter what: gravity! So Galileo is joining us all the way from the 1500s to fill us in on his theory about gravity. Then, we’re heading to space, and dropping a feather in a few different places to see what happens. Listen closely for a listener-submitted mystery sound, and a moment of um that answers this question: If you pick a flower, fruit or vegetable, is it still alive or is it dead?

White feathers float against a black background

What happens if you drop a feather in space?

The innies and outies of belly buttons

Today’s episode is all about your belly button aka navel aka umbilicus. And not just your belly button -- every single person you can think of has one. This means our listeners have LOTS of questions about them. We're going to tackle several of these fascinating navel-gazing questions like: is your belly button connected to your insides? Where does belly button fuzz come from? Why do some belly buttons stick out? And do cats and dogs have belly buttons? Plus, we have a tricky mystery sound for you to guess and a Moment of Um that answers the question: How do carrots grow if they don't have seeds?


Today’s episode is all about your belly button aka navel aka umbilicus. And not just your belly button -- every single person you can think of has one. This means our listeners have LOTS of questions about them. We're going to tackle several of these fascinating navel-gazing questions like: is your belly button connected to your insides? Where does belly button fuzz come from? Why do some belly buttons stick out? And do cats and dogs have belly buttons? Plus, we have a tricky mystery sound for you to guess and a Moment of Um that answers the question: How do carrots grow if they don't have seeds?

A guide to getting your COVID shot

Vaccines for kids and silver linings: Our second COVID summer

Kids over 5 can now get a COVID vaccine in the U.S. We know a lot of you have been waiting for this day and lots of you have sent us questions about the vaccine since the pandemic started: like what's in the COVID vaccine? How does it work? How do scientists know it's safe? And even if the vaccine isn’t available to you where you live yet, this episode will answer those questions -- and there are some fun games you can play along with us! 

If you have more questions about how COVID, the vaccines or anything else, you can send them to us here.


Kids over 5 can now get a COVID vaccine in the U.S. We know a lot of you have been waiting for this day and lots of you have sent us questions about the vaccine since the pandemic started: like what's in the COVID vaccine? How does it work? How do scientists know it's safe? And even if the vaccine isn’t available to you where you live yet, this episode will answer those questions -- and there are some fun games you can play along with us! Plus we've got some tips for how to distract yourself if you're feeling nervous, and an original song designed to help you shake that arm after the shot so it doesn't get as sore. Dance those ouchies away! Also: Three (3!) mystery sounds and a Moment of Um that answers the question: How does concrete harden?

Adults around the world are getting vaccinated against the coronavirus, and now, in a handful of countries (including the U.S.) kids over 12 can get vaccinated too.

We hear from a 13-year-old who participated in a clinical trial for a vaccine and get tips for how to navigate the world when only some people in your family are able to be vaccinated. Plus, Kara and Gilly share expert advice on how to handle big feelings as the world starts to open back up.

And a new Moment of Um answers the question: What are eye boogers?


How do the COVID vaccines work? // Brains On! Science Podcast For Kids

How effective are the COVID vaccines? // Brains On! Science Podcast For Kids

Shark teeth: The sharp bits of a squishy animal

In this episode, we’re asking sharks to say “aaaah”, and taking a close look at their chompers. We’ll see how shark teeth grow, and what those teeth can teach us about sharks of the past. We’ll also play a game of Jaws Jeopardy, and find out how sharks help keep the ocean healthy with their super snacking. Stick around for a listener-submitted mystery sound and a Moment of Um: why does steam rise in the air?


In this episode, we’re asking sharks to say “aaaah”, and taking a close look at their chompers. We’ll see how shark teeth grow, and what those teeth can teach us about sharks of the past. We’ll also play a game of Jaws Jeopardy, and find out how sharks help keep the ocean helping with their super snacking. Stick around for a listener-submitted mystery sound and a Moment of Um: why does steam rise in the air?

Spooky superstitions! Why we think 13 is bad luck

Just in time for spooky season, it’s an episode all about superstitions! Do you avoid the number 13? Or maybe it’s your lucky number, like Taylor Swift? In this episode we’ll look at why we have such strong feelings toward 13, and we’ll hear about other unlucky and lucky numbers around the world. Plus, Marc and Sanden will explain why our brains latch on to superstitions in the first place. Oh, and our favorite talking skeleton, Mr. Bonejangles, is back with a spine-tingling quiz! All that and a Moment of Um that answers the question: do cockroaches have hearts?


Just in time for spooky season, it’s an episode all about superstitions! Do you avoid the number 13? Or maybe it’s your lucky number, like Taylor Swift? In this episode we’ll look at why we have such strong feelings toward 13, and we’ll hear about other unlucky and lucky numbers around the world. Plus, Marc and Sanden will explain why our brains latch on to superstitions in the first place. Oh, and our favorite talking skeleton, Mr. Bonejangles, is back with a spine-tingling quiz! All that and a Moment of Um that answers the question: do cockroaches have hearts?

Crystals: More than just shiny rocks

This episode shines a light on crystals, and they’re sparkling right back at us! We’ll zoom way in on a diamond to understand the structure that makes crystals special, and hear about some unexpected crystals, too (hint: chocolate chip cookies contain a few different crystals!). Then, we take a look at how crystals form and get their cool colors. Plus, Marc and Sanden hunt down a hoax about Mesoamerican crystal skulls. 


This episode shines a light on crystals, and they’re sparkling right back at us! We’ll zoom way in on a diamond to understand the structure that makes crystals special, and hear about some unexpected crystals, too (hint: chocolate chip cookies contain a few different crystals!). Then, we take a look at how crystals form and get their cool colors. Plus, Marc and Sanden hunt down a hoax about Mesoamerican crystal skulls. 
And! A mystery sound and a moment of um: why does sugar taste sweet?

Squirrelsperience: Trying out squirrel skills

We’re heading to a squirrel-themed adventure course and practicing a few of the skills they use to survive: gathering nuts, traveling in trees, and speaking like a squirrel. 


In many places, tree squirrels are extra busy these days. It’s time for them to collect nuts to prepare for winter! So we’re heading to a squirrel-themed adventure course and practicing a few of the skills they use to survive: gathering nuts, traveling in trees, and speaking like a squirrel. We’ll also learn about how squirrels evolved, and hear about some of their surprising relatives.
Plus, a mystery sound and a moment of um: what chemical in apples mixes with oxygen to turn brown? 

The heroes we need to defeat the coronavirus

Eighteen months into our fight with this coronavirus, it may feel frustrating that we're still in this battle, but there are many reasons to feel hopeful. One reason is that we know a lot about this virus now and have plenty of tools to fight it. We meet the superheroes prepared to help us defeat the coronavirus: Sgt. Socially Distanced, the Masked Mentor, the Testmaster and the Vaxinator! Plus: Gilly, one half of the hit podcast Going Viral with Kara and Gilly, and a special guest explain what a virus variant is and how the delta variant is different from the original coronavirus. Also, journalist Sarah Zhang helps us understand how the pandemic could end.


Eighteen months into our fight with this coronavirus, it may feel frustrating that we're still in this battle, but there are many reasons to feel hopeful. One reason is that we know a lot about this virus now and have plenty of tools to fight it. We meet the superheroes prepared to help us defeat the coronavirus: Sgt. Socially Distanced, the Masked Mentor, the Testmaster and the Vaxinator! Plus: Gilly, one half of the hit podcast Going Viral with Kara and Gilly, and special guest explain what a virus variant is and how the delta variant is different from the original coronavirus. Also, journalist Sarah Zhang helps us understand how the pandemic could end.

All that, plus a new mystery sound and a Moment of Um that answers the question "How do skunks spray their stink?"

How to conquer Garbage Mountain

After getting a firsthand look at the history of trash, we’re having visions from garbage’s present and future this week. Producer Kunsang Dorjee visits a landfill to see what happens to our trash after we throw it away, and producer Ruby Guthrie shows us how we can make less trash and dispose the trash we do make in ways that are better for the planet. Plus: we hear from a kid who helped her class produce almost no waste during the school year. And our Moment of Um answers the question: if ants like sweet things, why don’t they attack beehives?


The invention of trash

A pair of ghost shoes visit Molly with a message: it's time to think about garbage. They predict that Molly will be visited by three visions of garbage, one from the past, one from the present and one from the future.


A pair of ghost shoes visit Molly with a message: it's time to think about garbage. They predict that Molly will be visited by three visions of garbage, one from the past, one from the present and one from the future.

Today, Producer Sanden Totten takes us on a time traveling journey to see how we started making all this trash in the first place. Plus: the Moment of Um answers the question: Are yawns contagious to animals?

Next week, we'll be back with a look at the present and future of garbage.

Take a deep breath: How does breathing work?

Breathing is a really cool thing. We breathe automatically without thinking about it, but we can also control our breath and play with it. We'll learn how our lungs work and why our bodies need this air in the first place. We'll also hear from a singer and a free diver about how they've trained their breath to do remarkable things -- and how you can too! And we'll talk to a doctor about how deep breathing can help you feel less stressed and she'll teach us an exercise you can do whenever anxiety starts to creep up. Plus: Our Moment of Um answers the question: what is the smallest unit of measurement?

What does the giraffe say? Our animal mystery sound extravaganza!

When one of our listeners wrote in with an animal sound mystery (What sound does a giraffe make?) we set out to find an answer. We came back with lots of other fascinating animal sounds, so we decided it was time for an all-animal mystery sound extravaganza! Open up your ears and get ready to play! 


When one of our listeners wrote in with an animal sound mystery (What sound does a giraffe make?) we set out to find an answer. We came back with lots of other fascinating animal sounds, so we decided it was time for an all-animal mystery sound extravaganza! Open up your ears and get ready to play!

Plus, our Moment of Um answers the question: Why do daddy long legs have such long legs?

Why do we lose teeth?

From wigglers to lost teeth traditions, we're looking at all things chompers. Chew on this!


Today we’re looking at a phenomenon that happens to all of us: losing our baby teeth and getting new ones! So how do our teeth grow in and what makes them fall out? Naturally, a group of wandering teeth helps us explain. We'll also find out why we have two sets of teeth in the first place. A chatty tooth travel agent will introduce us to all the different ways to send our baby teeth off in style and we'll play a game that will test your knowledge of animal teeth. Plus, the Moment of Um answers the question "Why do bees make a buzzing sound?"

What causes wildfires?

A fire can be super useful or cozy or even magical. But it can also be dangerous -- and in the case of wildfires, if they burn long and hot enough, they can destroy ecosystems and send lots of harmful smoke into the air. 


A fire can be super useful or cozy or even magical. But it can also be dangerous -- and in the case of wildfires, if they burn long and hot enough, they can destroy ecosystems and send lots of harmful smoke into the air. 

In this episode, we're going to find out why wildfires are getting bigger and why wildfire season is lasting longer now. We'll learn how the tribes who've lived in what is now called Northern California managed the forests and kept fire in check for thousands of years, and how those practices are being used today. 

We'll hear from a friendly house about how to stay safe from smoke inside and find out how firefighters work to contain fires once they've started. 

Plus, our Moment of Um answers the question: Is the name of a letter considered a word?

Million Bazillion answers your questions about money

Today we’re sharing an episode with you from our friends at Million Bazillion, the podcast that answers the questions kids have about money. They help dollars make more sense and they’re back for a whole new season! 


We’ve got an extra special episode for you today from our friends at Million Bazillion, the podcast from Marketplace that answers the questions kids have about money. They help dollars make more sense and they’re back for a whole new season!
 
Today, hosts Jed and Bridget answer a question from two curious listeners who want to know why we pay taxes. In answering the question, they come across the legendary Robin Hood, known for his hatred of taxes. Back in his day, tax-collecting sheriffs forced people to pay money to a king, who decided how those taxes were spent. These days our tax system works a bit differently. We get to vote for people who’ll spend that money on things we care about — like schools and libraries, health care for elderly people, police, parks, sewers and so on. With the help of a rambling troubadour and a tax policy expert, Jed and Bridget teach Robin Hood that the way tax dollars are spent today reflects what we prioritize as a society. Plus, we’ll ask random kids some not-so-random questions.
 
Million Bazillion is a collaboration between Brains On and Marketplace. It’s hosted by Jed Kim and Bridget Bodnar. You can listen to more episodes here, or subscribe at Apple Podcasts, Spotify, Google Podcasts, or wherever you get your podcasts.
 

Why do mosquitoes bite? Scratching that itch

Have you been itching to find out more about mosquitoes? Check out this buzz-riffic episode all about those pesky skeeters.


In this episode, we're tackling all the mosquito questions that have been bugging our listeners. Why do they bite? Why do the bites itch? Is scratching them a good idea? Why do some people seem to be more delicious to mosquitoes? How can we keep them away from us? And are mosquitoes good for the world? The Hoax Hunters make an appearance plus the Moment of Um answers the question, "What is a solar flare?"

Why do songs get stuck in our heads?

You know that feeling where you get a snippet of a song stuck in your head and it loops over and over? Those hard to shake songs are also known as earworms, and in this episode Molly has a particularly sticky one in her brain. We'll find out why some songs are catchier than others and, most importantly, scientifically-proven ways to get rid of them. 


You know that feeling where you get a snippet of a song stuck in your head and it loops over and over? Those hard to shake songs are also known as earworms, and in this episode Molly has a particularly sticky one in her brain.

We'll find out why some songs are catchier than others and, most importantly, scientifically-proven ways to get rid of them.

Plus, we'll hear a mystery sound and a Moment of Um that answers the question: "Do spiders have bones?"

Adults around the world are getting vaccinated against the coronavirus, and now, in a handful of countries (including the U.S.) kids over 12 can get vaccinated too. 

We hear from a 13-year-old who participated in a clinical trial for a vaccine and get tips for how to navigate the world when only some people in your family are able to be vaccinated. Plus, Kara and Gilly share expert advice on how to handle big feelings as the world starts to open back up. 


Do dogs know they're dogs?

Do dogs know that they are dogs?

We treat dogs like they're part of the family. But do they know they are a different species, or do they think they're just short, four-legged people?

In this episode, canine cognition researcher Alexandra Horowitz helps us puzzle out this question. We’ll also find out what happens (or doesn’t) when a dog looks in the mirror. Dogs are always dozing, and we’ll check in to see if they are dreaming too. And, we take a quick trip around the world in the language of barks. 

All that, plus a brand new Mystery Sound and moon-filled Moment of Um.


We treat dogs like they're part of the family. But do they know they are a different species, or do they think they're just short, four-legged people?

In this episode, canine cognition scientist Alexandra Horowitz helps us puzzle out this question. We’ll also find out what happens (or doesn’t) when a dog looks in the mirror. Dogs are always dozing, and we’ll check in to see if they are dreaming too. And, we take a quick trip around the world in the language of barks.

All that, plus a brand new Mystery Sound and moon-filled Moment of Um!



We often talk about our canine pals like they have the emotions and language of people but do dogs really understand they're dogs the way that we understand we're humans? In this episode, canine cognition researcher Alexandra Horowitz helps us puzzle out this question. We’ll also find out what happens (or doesn’t) when a dog looks in the mirror. Dogs are always dozing, and we’ll check in to see if they are dreaming too. And, we take a quick trip around the world in the language of barks. All that, plus a brand new Mystery Sound and moon-filled Moment of Um!

How do dogs "see" with their noses? - Alexandra Horowitz

Our 200th episode is SUN-sational!

For our 200th episode, we get an up close and personal look at the sun. 


There’s no better way to celebrate our 200th episode than with our own shining star: the sun! In this episode we speak with Dr. Nicola Fox, who leads a team of NASA scientists that sent a probe to collect data and zoom by the sun. We also hear some great listener suggestions on what new planet could be added to our solar system. We even get a chance to check in with The Sun and her weekly broadcast, That’s Hot.

Our 200th episode wouldn’t be complete without a visit from some of our favorite pals: Bob, Gungador, Harvey and Elevator! Of course there’s a new Mystery Sound too. And the Moment of Um comes just in time for mosquito season, because it answers the question: Why do we itch?

Thank you so much for helping us make 200 episodes! We could never have done it without your questions and encouragement, and we can’t wait to make 200 more!


How NASA's Parker Solar Probe Will Survive the Sun

How far can a cloud travel?

Can the same cloud you see travel halfway across the world?


We’ve all played the “what does that cloud look like” game. Maybe you saw a bunny… or an airplane… or a unicorn. What if that same cloud also be seen by someone in a far off continent? That’s what a listener in Minnesota wondered. He wanted to know if the same cloud he saw in a park near his house could also be seen in Africa.

We talk to Deanna Hence, one of our favorite weather experts, and she tells us about how clouds travel. We also dust off the Zoom Ray to learn about what is inside of a cloud. And have you ever noticed the similarities between cloud types, like cumulonimbus, and magic spells from Harry Potter? Well, we have, and we made a game out of it!

We also have a brand new Mystery Sound for your guessing pleasure (or torture) and a Moment of Um that answers the question: Why do pugs have such scrunchy faces?  

Totally Slothsome: All about sloths

Slow moving sloths and their perma-smiles have captured the heart and minds of people everywhere. Find out what makes this slowest moving mammal tick. 


There’s more to sloths than slowness. They’re great at saving energy, hanging upside down, and swimming! In this episode, Sloth Appreciation Society founder Lucy Cooke stops by to tell us all about these amazing animals. We also get into a sloth mystery: The Case of the Perilous Poop Journey. Luckily, there’s a sloth sleuth on the case. And sloths aren’t the only animals who aren’t in a hurry — a few others show off their slowest skills.

There’s also a Mystery Sound for you to guess, and a Moment of Um: Why do ostriches stick their heads in the ground?

How do computers store so much info in such a tiny space?

Microchips are in our phones and laptops. They’re in our cars and refrigerators. They’re in our watches and vacuum cleaners. They are everywhere, but where did they come from?


If you translate “Hello! How are you?” to binary code, it looks like this: 01001000 01100101 01101100 01101100 01101111 00100001 00100000 01001000 01101111 01110111 00100000 01100001 01110010 01100101 00100000 01111001 01101111 01110101 00111111

This episode takes a look at how computers can do so much with such tiny parts. But computers weren't always small -- so we take a look at where computers came from. We visit Ada Lovelace, whose love of math and weaving paved the way for modern-day computers. And we hear about the material that let computers shrink from the size of a room to something that fits in our pockets. There’s also a visit from a yak and a ram, but you’re just going to have to listen to find out why.

All that plus a new Mystery Sound and Moment of Um that answers the question: what is the flavor of root beer?

How does taste work? We react to our very first episode!

Wow, it’s been almost 10 years since we put out our first episode about eating. We’re revisiting the episode with some behind the scenes commentary.


 Brains On has a very special milestone coming up -- it’s almost our 200th episode! To celebrate, we're re-listening to our very first episode which was all about eating. We'll play the episode and chime in with commentary to give you some behind the scenes glimpses and backstories along the way. We’ll also hear an update from our very first co-host ever -- Ian Roberts, who is now a college student and an adult. Plus a brand new Moment of Um answers the question: Why do we have birthmarks?

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