Everything in our world is powered by energy. We need it to drive our cars, bake cupcakes and even jump up and down on the bed! All of this energy comes from different sources, like gasoline and wind power. Even the food that powers our bodies is a source of energy. But almost all of the energy on Earth first came from the same place: the sun!

In this episode, we’ll find out how the sun powers so much of our lives. Plus, we’ll learn how the amount of energy in the universe has stayed the same since the very beginning of time, which scientists call the Big Bang. Mind-blowing, right? All that, plus a brand new mystery sound and a look at some really cool possible future sources of energy!

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JOSEPHINE: You're listening to Brains On! Where we're serious about being curious.

SUBJECT: Brains On! is supported in part by a grant from the National Science Foundation.


SUBJECT: Feeling run down, drained, slow like a slug with a broken leg? If slugs had legs and bones and-- you know what I mean. You need a boost. You need a drink that will bring you back to life. You need Screaming Eagle Energy Brew.


The ultimate energy drink filled with scientifically unproven energy boosters like water from a hurricane, dust scraped off an old race car--


--sweat from a runner's shoe, spit from a cheetah--


--and the tears of a screaming eagle.


SUBJECT: I'm not sad. These are tears of awesomeness.


SUBJECT: Screaming Eagle Energy Brew, will it give you energy? Hopefully. Will it make you look cool? Definitely. Will it wreck your stomach and give you horrible gas? Five out of five doctors say, absolutely. So drink up and wake up with Screaming Eagle.


SUBJECT: So, Marc, what do you think? Do you want to invest in my new energy drink company?

MARK SANCHEZ: Um, are you legally allowed to sell that?

SUBJECT: Only in specific markets.


SUBJECT: International waters and outer space.

MARK: Yeah. I'm going to pass. That drink sounds terrible. Like, it puts the pep in Pepto Bismol.

SUBJECT 3: Ooh, that's good. Can I use that as our slogan?


MOLLY BLOOM: You're listening to Brains On! from APM Studios. I'm Molly Bloom. And my co-host today is Josephine from Astoria, Oregon. Hi, Josephine.


MOLLY BLOOM: Today, we're talking all about energy. Energy is a word that can be used in lots of different ways, like--

JOSEPHINE: Ugh! I'm so tired. I don't have any energy.


JOSEPHINE: It's time we invest in clean energy, like solar power or wind.

MOLLY BLOOM: Or even--

JOSEPHINE: Oh, I used to focus on knitting hats, but now I'm using my creative energy to make decorative toilet seat covers.


MOLLY BLOOM: So, Josephine--


MOLLY BLOOM: --what comes to mind when you hear the word energy?

JOSEPHINE: I normally would think about this big tank of energy. And then whenever I turn on a light bulb, it takes a very small piece of energy and puts it in the light bulb.

MOLLY BLOOM: Nice. And can you name some places you see energy in our day-to-day lives?

JOSEPHINE: When I turn on a light switch and then in a fraction of a second, a light bulb will turn on; or when me and my mom are going to watch a movie, when we hit the On button, it takes only five seconds for it to turn on since they're not connected.

MOLLY BLOOM: OK. So I've got a question for you, and I think I know the answer. But--


MOLLY BLOOM: --I'm going to ask it. Would you describe yourself as a high-energy person or a low-energy person?

JOSEPHINE: I'm a very high-energy person. Whenever I see a friend somewhere that I know at a park or a grocery store, I'm like, must engage, must engage, must engage.


MOLLY BLOOM: Sounds like you're an extrovert. So are there some things in your life that you feel like give you energy? It sounds like seeing other people does. What else gives you energy?

JOSEPHINE: Some of my favorite foods, like a grilled cheese sandwich and tomato soup or spaghetti--


JOSEPHINE: --and meatballs.

MOLLY BLOOM: Those are good sources of energy.

JOSEPHINE: Yeah. Like, just really good foods that I really like.

MOLLY BLOOM: So when scientists talk about energy, they usually mean something that has the ability to do work. Like, it can power something. Gas is a source of energy. You can use it to power a car.

JOSEPHINE: Food is also a source of energy. When you eat it, your body breaks it down, and the energy from it powers your body.

MOLLY BLOOM: We use energy to do all sorts of work for us. It lights our light bulbs.


JOSEPHINE: Powers our vehicles.


MOLLY BLOOM: Cooks our food.


JOSEPHINE: And runs our factories.


MOLLY BLOOM: We sometimes talk about energy like we're using it up, burning it off, or draining it out, but here's something to blow your mind. The total amount of energy in the universe never changes. It's been exactly the same since the universe was formed and will stay the same forever.




MOLLY BLOOM: This cool fact is called a fundamental law.

JOSEPHINE: A fundamental law isn't like the laws written by humans-- like the laws that tell us how fast we can drive, or how old do you have to be to vote.

MOLLY BLOOM: Right. A fundamental law is based on observations scientists have made about how the universe works. We call them laws because pretty much everything in the universe seems to follow them. The one we're talking about today is called--


SUBJECT 4: The law of conservation of energy.

MOLLY BLOOM: And this law says that energy cannot be created or destroyed. When we use energy, we're actually just moving it around or changing it from one form to another. We'll explain this more in a bit.

JOSEPHINE: But first, this brings us to a very woe-worthy question from our pal, Penny.

PENNY: My name is Penny from Springboro, OH. And my question is, if energy cannot be created or destroyed, then how is it here in the first place?

MOLLY BLOOM: It's a wonderful question. And here's the part where I tell you the most frequently used answer in all of science-- we don't know, yet.

JOSEPHINE: What we do know is that all the energy in our universe was here from the very moment the universe, as we know it, began, a moment sometimes called--


SUBJECT 4: The big bang!

MOLLY BLOOM: Let's show you by jumping way back, rewinding all the way to the start of the universe.


JOSEPHINE: It's almost 14 billion years ago.

MOLLY BLOOM: Before the universe even existed.

JOSEPHINE: No planets, suns, or galaxies, nothing.


MOLLY BLOOM: Scientists think the universe began with a single, teeny tiny speck, a million billion billionth the size of an atom. Atoms are the smallest building blocks of everything in our world. And this speck was much smaller than an atom.

JOSEPHINE: And suddenly, in a fraction of a second, that speck expanded.


MOLLY BLOOM: That's why we call this theory the Big Bang, because of that very fast expansion, almost like an explosion. And all the energy in our universe was there.

JOSEPHINE: It shot out in all directions as the universe expanded.

MOLLY BLOOM: It sent space and matter hurtling out.

JOSEPHINE: Eventually, gases formed stars. These stars exploded, making rocks and dust. And the rocks and dust became new stars and even planets.

MOLLY BLOOM: And after a long, long, long time, our sun formed, along with all the planets in our solar system.

JOSEPHINE: And that sun, our sun, gives off energy in the form of light. And that energy was created when the universe was.

GWEN HOLDMANN: So as far as scientists know, the total amount of energy in the entire universe has been the same since the Big Bang, since the universe was formed.

MOLLY BLOOM: That's scientist Gwen Holdmann. She studies energy at the University of Alaska Fairbanks.

JOSEPHINE: She says energy takes lots of different forms as it moves around.

GWEN HOLDMANN: Any time that something is moving or changing or heating up, its energy that enables that to happen. So kind of all of the big and small changes that happen in the universe from a star exploding to the vibration of individual atoms and the darkest, coldest part of outer space all depend on energy; and on Earth, everything from a pebble rolling downhill to a blade of grass growing, to sound waves traveling through the air. Any time there's motion or change, there's energy involved in that.

MOLLY BLOOM: So energy isn't something that's used up, burned off, or destroyed.

JOSEPHINE: Yeah. Instead, it's just moving around, passing from thing to thing, making an epic journey across the universe.



MOLLY BLOOM: Whoa. How does that idea make your brain feel, Josephine?

JOSEPHINE: It makes me think of Star Wars.


JOSEPHINE: Because they're journeying. They're having an epic journey across the universe.

SUBJECT: (SINGING) Brains On! On! On!

MOLLY BLOOM: Let's hit pause on the big ideas for a minute, Josephine. And instead, listen to a big noise.


MOLLY BLOOM: It's the--

SUBJECT: (WHISPERING) Mystery sound.

MOLLY BLOOM: Are you ready, Josephine?

JOSEPHINE: I'm always ready.

MOLLY BLOOM: Here it is.


Hmm, what is your guess?

JOSEPHINE: OK. So when I first heard it, I immediately thought of like fruit being peeled, but then I thought fruit doesn't make that sound. Then I thought tinfoil.


JOSEPHINE: But tinfoil is a bit more snap, not much more of a rounded sound.

MOLLY BLOOM: Ooh I like that description of rounded sound. You want to hear it again?


MOLLY BLOOM: OK, here it is.


JOSEPHINE: Now I'm thinking it's like a rewind thing like those weird things that move with that thing that you can rewind it, and then it moves forward, or like Scotch tape.

MOLLY BLOOM: Josephine, you have excellent ears. We're going to hear it again, and we're going to get another chance to guess and hear the answer at the end of the show.

JOSEPHINE: After the credits.


MOLLY BLOOM: We're working on an episode about prehistoric creatures. We're talking dinosaurs, giant sea scorpions, megalodon, sabertooth tigers, mammoths, so many cool prehistoric creatures out there. So we want to hear from you. We're asking you to write a haiku dedicated to your favorite prehistoric creature.

Remember, haikus are poems that have a special format. They have five syllables in the first line, seven syllables in the second, and fie syllables in the third A syllable is one beat or sound in a word.

The word grand has one syllable, and the word reptile has two syllables. Here's an example of a haiku. Grand dimetrodon, ancient reptiles, majestic sail, silent now they lie. Josephine, do you have a haiku for your favorite prehistoric animal?

JOSEPHINE: Yes, indeed, I do, Molly.

MOLLY BLOOM: May I hear it, please?

JOSEPHINE: Yes, you may. Sea creatures go low. Birds go very, very high. Look, woolly mammoths.

MOLLY BLOOM: Oh, Josephine, such excellent work. I love it. Listeners, send us your prehistoric haikus at brainson.org/contact. And while you're there, you can send us mystery sounds, drawings, and questions.

JOSEPHINE: Like this one.

SUBJECT: My question is, do bees have noses?

MOLLY BLOOM: Again, that's brainson.org/contact.

JOSEPHINE: And keep listening.

You're listening to Brains On! I'm Josephine.

MOLLY BLOOM: And I'm Molly. So we just heard that energy is never created or destroyed, it just moves around.

JOSEPHINE: And energy is everywhere.

MOLLY BLOOM: Here on Earth, pretty much all of our energy can be traced back to one source-- the sun.

JOSEPHINE: But how? I mean, I, for one, get my energy from spaghetti and meatballs. That's not the sun.

MOLLY BLOOM: Food is like stored energy, but that energy in the food started with the sun. Let's take an example. Let's say there's a kid jumping around the house with lots of energy because they just had some delicious yogurt.


But where did that energy in the yogurt come from? Let's rewind again.


It all started on a sunny day in a field of grass. The sun sent light down to that grass, making it grow. Then, a cow came by to eat it.


The cow digested that grass and got energy from it. Some of that energy went into making milk.



Someone took that milk from the cow and turned it in to yogurt. Eventually, that kid ate the yogurt, and it powered their playtime.


JOSEPHINE: So it all started with the sun? Wow.

MOLLY BLOOM: Yeah. Pretty much all the foods we eat start with energy from the sun. Then that energy is passed around until it reaches our bellies.

SUBJECT: Thanks, sun.

MOLLY BLOOM: Are you ready for another mind blower?

JOSEPHINE: I'm always ready, Molly.

MOLLY BLOOM: Coal, that dark black rock that's been dug up and burned for heat and to fuel power plants for a long time, the energy it contains can also be traced back to the--

JOSEPHINE: Let me guess, the sun?


MOLLY BLOOM: You got it, the sun. Here's our scientist pal, Gwen again.

GWEN HOLDMANN: Coal comes from trees that were alive many, many millions of years ago. And when those trees died, they were buried over time and squished and cooked underground to become coal.

JOSEPHINE: Hang on, coal is just squished up old trees?

MOLLY BLOOM: Yeah. To explain, let's rewind again to about 300 million years ago.


This was long before the dinosaurs. The Earth was covered in huge swampy forests and shallow oceans. There were giant dragonflies, giant millipedes, even giant trees that looked like ferns.

JOSEPHINE: So much giant stuff.

MOLLY BLOOM: So much. And the sun was shining down, beaming its sunshiny energy all over the Earth.

SUBJECT: Thanks, sun.

MOLLY BLOOM: The giant ferns and trees and other plants soaked up that sun energy and used it to grow. When these plants eventually died, some of them got buried underground. And over millions of years, they turned into coal.

JOSEPHINE: So when we burn coal, we're using that ancient sun energy that trees stored a long time ago?

MOLLY BLOOM: It's kind of like we're using a time machine and unlocking that energy absorbed from the sun millions of years ago. And Gwen says other fossil fuels were also made from that ancient sun energy.

GWEN HOLDMANN: Oil and gas are really similar. But in that case, they're mostly the remnants of marine, plankton, and algae who were using energy captured by plants and microorganisms alive millions of years ago. We call them fossil fuels, but they're really just stored solar energy that's captured over different periods of time.

SUBJECT: Brains, brains, brains on.

MOLLY BLOOM: But there are some major problems with fossil fuels. One is that we will eventually run out of them.

JOSEPHINE: Right. There's only so much ancient squished-up wooden plants buried underground. Once we use it all, it will take millions of years for the Earth to make more.

MOLLY BLOOM: The other big downside is that when we burn fossil fuels for energy, it also releases a lot of carbon dioxide gas into the atmosphere.

JOSEPHINE: And this carbon dioxide basically acts like a big blanket, making the planet warmer and causing climate change.

MOLLY BLOOM: So, scientists are developing other forms of energy that are better for the planet. And believe it or not, many of them are sun-powered, too.

JOSEPHINE: Let's start with wind power.


MOLLY BLOOM: We're able to harness the power of the wind through big wind turbines.

JOSEPHINE: Oh, yeah, those really tall thingies that look like giant fans.

MOLLY BLOOM: Right wind is created when the sun heats up the Earth's surface, which makes the air move around. That wind spins the blades on those super tall turbines. The spinning is converted into energy, and it's used to power stuff like homes or factories.


SUBJECT: Thanks, sun.

JOSEPHINE: Next up, hydropower-- that's when we harness water and turn it into electricity.

MOLLY BLOOM: We can capture some of the energy of moving water and use it to drive a machine. Water is constantly going through the water cycle, you know, evaporating from a liquid into a gas, becoming rain, falling to Earth and into lakes and rivers, and then flowing out to sea, and evaporating again.

JOSEPHINE: And what kicks off the evaporation? Say it with me, now. The sun.

MOLLY BLOOM: So the sun supplies the energy for all these other sources of power, too.

SUBJECT: Thanks, sun.

JOSEPHINE: There are a couple kinds of power that don't get their energy from the sun.

MOLLY BLOOM: Right. Like, geothermal energy--

JOSEPHINE: That's heat that comes from inside the Earth.

MOLLY BLOOM: --and nuclear power. And scientists are dreaming up new ways to get energy all the time.

JOSEPHINE: You might even find this future energy technology in your house someday. Huh, I wonder what future me will use to charge my future phone or my future electric toothbrush? I wish I could see some kind of commercial from the future to learn more.

MOLLY BLOOM: One future energy commercial coming right up.


SUBJECT: Hi, friends, has this ever happened to you?

SUBJECT: Five trillion twinkling holiday lights? What are you doing with 5 trillion twinkling holiday lights. It's not even the holidays. It's the middle of summer. And you're going to blow the power for the whole city.

SUBJECT: Oh, this isn't just any old light display. This is the world's largest light up hot dog. When I'm done, you'll be able to see this weenie from space. Just have to plug this baby in and--


--there. It's so beautiful, so brilliant. It's so--


SUBJECT: Dark? Yeah, you blew the circuits using all that power.

SUBJECT: Major bummer. But you, too, can make the world's largest light up hot dog with solar space power.


It's exactly what it sounds like-- solar panels, but in space. Just slap a couple solar panels on a satellite, and you're good to go. The panels will collect sunlight 24/7. Because in space, there's no night, no clouds, perfect for making solar power. Then we just beam all the power wirelessly right down to the Earth. Now, let's light up that weenie.

SUBJECT: Wow, it's the most luminous hot dog I've ever seen.

SUBJECT: Solar space power, it's like regular solar power, but in space.

MOLLY BLOOM: What do you think about 24/7 solar space power?

JOSEPHINE: I think it's going to be like a big hit, like Disney+.


And then everyone wants it, but then everyone always has it, and then everyone just thinks they've had it for a million years, and that it's just like this really boring thing.

MOLLY BLOOM: Yeah, so it's going to be this brand new thing, but then maybe it'll eventually be something we all take for granted?


MOLLY BLOOM: Yeah. This is an idea some engineers think could be huge. Just one solar panel in space could collect eight times the energy as a solar panel here on the ground because it could be soaking up those rays all day, every day.

In June of 2023 for the very first time, scientists tried this and beamed that energy back to Earth. It's not common yet, but it's got promise.

JOSEPHINE: So one day, my electric toothbrush could use space power? I like the sound of that.

MOLLY BLOOM: And that's not the only new type of energy tech scientists are working on. Ready for another commercial?


SUBJECT: (SINGING) Make use of that pesky humidity with hygroelectricity.


SUBJECT: You know that summertime feeling? The heat is clinging to you. The air feels thick and wet and heavy. That's humidity.

SUBJECT: I feel like I'm swimming in my own sweat.

SUBJECT: Well, what if I told you you could use that gross, heavy, humid air to generate electricity? Introducing hygroelectricity.

SUBJECT: Don't you mean hydroelectricity?

SUBJECT: Nope. Hydroelectricity creates power from moving water, but hygroelectricity draws power from the air itself. When air is humid, that means it has millions of tiny water droplets in it. And between those droplets, there are even tinier electrical charges zipping around.

SUBJECT: Wow! Like a teeny tiny electric sock hop.

SUBJECT: Um, kind of. Anyway, scientists believe they might be able to use super tiny wires to capture this electricity and put it to use.

SUBJECT: That's amazing. Could it help me power an air conditioner? Because honestly, I've basically swept myself a new swimming pool.

SUBJECT: Not yet, but we hope so.

SUBJECT: Then can I get a popsicle? Gatorade dumped on my head? Anything? Please, somebody help me. I'm so sweaty.


SUBJECT: (SINGING) Make use of that pesky humidity with hygroelectricity.

MOLLY BLOOM: That is a catchy jingle. So Josephine, what did you think of hygroelectricity?

JOSEPHINE: It sounds like you're taking sweat from a runner's shoe and then putting it into an energy drink.

MOLLY BLOOM: It's very humid here in Minnesota right now, and that sounds ideal. I would love if it would at least have a purpose that I'm this sweaty.

JOSEPHINE: Yeah, because then you would be swimming in a pool of sweat, like Sweaty Betty.


But wait, they said there are tiny electrical charges zipping around in the air. These must be really, really small. How can we catch enough energy from them?

MOLLY BLOOM: That's a tough one, which is probably why we won't see a lot of power from hygroelectricity for a while. But scientists have been able to capture an itty bitty amount of power using a tool that's thinner than a human hair.

JOSEPHINE: Hum. That sounds like it would take a whole lot of those super thin devices to make hygroelectricity work.

MOLLY BLOOM: Bingo. Hygroelectricity is still a little ways off, but people used to say the same about solar power. Ready for a final fabulous and fantastic future energy commercial? Here we go.


SUBJECT: Your favorite outfits are your favorites for a reason, because when you look good, you feel good. But have you ever wondered if your clothes can do more? Well, now they can. Introducing Electrotex, the textiles with a spark.


Our scientists have created clothing that not only looks stylish, but it actually makes electricity just from wearing it. Every time the cloth rubs against something, the friction creates a tiny zap of electricity.


Then, we capture that electricity. That means you can kayak to power your computer, rock climb to run your radio. You can even marangi to power your microwave. So use Electrotex to save power and look good doing it.

SUBJECT: Electrtex is a hypothetical clothing company. This technology is still in experimental stages. All items sold separately or, in fact, not at all.

SUBJECT: Electrotex, fashion is power.


MOLLY BLOOM: So all of these new technologies sound amazing. And even though scientists are still working on them, maybe someday soon, we'll see electricity-collecting clothes, space solar, or even humidity power at work in our own homes.


JOSEPHINE: Energy is a central part of our daily lives from powering fairy lights to heating up burritos. Yum!

MOLLY BLOOM: The universe has had the same amount of energy since it was created during the Big Bang.

JOSEPHINE: This means that energy is never created or destroyed. It just moves around.

MOLLY BLOOM: And a lot of energy on Earth comes from the sun.

JOSEPHINE: We collect that energy by burning fossil fuels like oil, gas, and coal and from the wind, water, and directly from the sun.

MOLLY BLOOM: And some scientists are even working on new ways of getting energy from the sun, like drawing energy from humid air, from the clothing we wear, and even from solar power in space. That's it for this episode of Brains On!

JOSEPHINE: This episode was written by Molly Bloom and Molly Quinlan Artwick and was produced by Rachel Breese, Rosie DuPont, Anna Goldfield, Nco Gonzalez Wisler, Ruby Guthrie, Marc Sanchez, Anna Weggel and Aron Woldeslassie.

MOLLY BLOOM: Our editors are Shahla Farzan and Sanden Totten. And our executive producer is Beth Perlman. This episode was sound designed by Rachel Breese and by Nate Crockett. Many Thanks to Roxy Highfield and Barbara Highfield. The executives in charge of APN Studies are Chandra Kavati, Joanne Griffith, and Alex Schaffert.

JOSEPHINE: And I want to give a special thanks to Camp Kiwanilong, Hannah Patrick. And this person knows exactly who they are, Slightly Smaller Lou/Grace. Brains On! is a non-profit public radio program.

MOLLY BLOOM: There are lots of ways to support the show. Head to brainson.org.

JOSEPHINE: While you're there, you can subscribe to our amazing Smarty Pass, where you can listen to ad-free episodes and amazing super, special bonus content.

MOLLY BLOOM: And you can submit your questions and mystery sounds. That reminds me, Josephine. Are you ready to listen to that mystery sound again?

JOSEPHINE: I'm always ready.

MOLLY BLOOM: Wonderful. Here it is.


OK, what are your new thoughts?

JOSEPHINE: So I know it's not Scotch tape, and I don't think it's one of those rewinding thingies because I'm like, it doesn't sound that loud. And I also heard someone moving around in the background.

MOLLY BLOOM: So tell me, what could it be if it's not those things?

JOSEPHINE: It's something moving, I know that.

MOLLY BLOOM: Something moving. It sounded like there was something being unrolled or something or wound up.


MOLLY BLOOM: Can you think of anything that does that?

JOSEPHINE: I want to say tape, but I know it's not that.

MOLLY BLOOM: OK. Are you ready for the answer?

JOSEPHINE: I'm always ready, Molly.


Like I said, I'm always ready.

MOLLY BLOOM: Here is the answer.

AMELIA: My name is Amelia from Jackson Heights, New York, and that was the sound of me unwinding and releasing a measuring tape.

MOLLY BLOOM: Measuring tape.

JOSEPHINE: Oh, I knew it was something like that. I have a measuring tape. I was close. I said tape, but tape doesn't sound like that.

MOLLY BLOOM: I agree, you were very close. There was tape in the answer. So I'm giving you partial credit, for sure. Nicely done.

JOSEPHINE: Thank you.


MOLLY BLOOM: Now it's time for the Brains Honor Roll. These are the incredible kids who keep the show going with their questions, ideas, mystery sounds, drawings, and high fives.




We'll be back next week with more answers to your questions.

JOSEPHINE: Thanks for listening.

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