What's up, Smarty Pants? It's Jerry. When you think of volcanoes, what do you think about?

Crazy jets of fiery stuff spring everywhere, lava flowing and maybe Hawaii?

But as scary as volcanoes are, they're actually an amazing window into the science and history of the Earth.

So come hang with me in my neighbor Vulcan and my Aunt B, as we dig deep into the Earth's crust on this very hot episode of Who Smarted.

I'm going to bake a cake for Bob. Bake on the cake today. Oh, it's gonna taste great.

Taste filled right. Hooray! Last step, the secret ingredient. Wait, where's...

Oh no! No! I can't be out of my mind!

Oh, it doesn't hurt to ask. Coming! Hello. Hi neighbor. We haven't officially met. My name's Vulcan. I just moved in next door.

Nice to meet you Vulcan. Cool name. I'm your trusty narrator. What's up?

Well, I have luck would have it. I was baking a cake when I realized I was all out of the key ingredient. I feel so silly. No worries. What do you need? Sugar, flour? No, no, I've got that. I need two gallons of lava. Huh?

Come again? I need two gallons of lava. Can you spare some? Lava? Yeah, my new girlfriend is coming over. For dinner and I promised I'd bake my famous lava cake for dessert. Oh boy. You mean like fiery molten crazy hot lava? Can't make a lava cake without lava. Am I right?

Sorry, what did you say your name was again? Vulcan? Oh, like the Roman god of fire Vulcan? Whoa, good guess. That's me. Have we met before? No, I've just heard your name before. I'm flattered. So, about that lava. I don't have any. Shoot. Well, it's too late to go to the store. My date's ruined before it has even begun.

Hang on, don't throw in the towel just yet. I think I know where to find some lava. Really? Yeah, but we're in for quite a trip. We need to find out where lava comes from, what it's made of, and how and why it exists in the first place. So get ready for another whiff of science on...

So, is it cool if I call you Vulc? Sure. Great. So, Vulc, I'm guessing you know where lava comes from, right? I mean, I'm the Roman god of fire. So...

Obviously, I know where lava comes from. I totally... Well, you know where it comes from, right? I do. How about you listening at home? Do you know where lava comes from? Does lava rain down from the clouds? Does lava grow on trees? Does lava come out of the ground from volcanoes? That's right. Lava comes from volcanoes.

For the record, I was gonna say that. I don't see any volcanoes around here. Nope. We need to take a trip to your home. No, man. I checked my entire kitchen. I'm fresh out of lava. No, you're home. Where you were born? Mount Edna in Italy. Oh, my home. Yeah, let's go.

Oh, that's been years since I've been here. Wow. I've forgotten how beautiful Mount Edna is. Yes, and can you believe that big majestic mountain is actually a volcano? It is? I'm insured it is, but I'm not seeing any lava. Nope. Because right now, the lava is buried deep beneath the volcano. That read underground. So, how are we gonna get it out? Do we just dig a hole? Not quite.

Before we can get to the lava, you've got to understand a bit more about where it's hiding. And to help show you, I'm gonna need an egg. A hard boiled egg. Oh. Now, for you listening at home, feel free to hit pause and ask your parents to help you hard boil an egg of your own. Or if you're in a car or no, we are near any eggs, or just can't boil one right now. Just imagine it for now. And maybe you can try it later. Okay. For those of you who do have an egg, of course, let it cool first, and don't peel it yet. Oh, man. I'm so sorry. Oh, man. I'm so sorry. I'm so sorry. I'm so sorry. So, I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry. I'm so sorry.

Okay. I've got a hard boiled egg. Excellent. Okay. Now, pretend this hard boiled egg is the earth. Just like this egg, the earth is made up of layers. The outermost layer is called the crust. This is the part of the earth you see. It's the ground you walk on. The soil that food grows out of. And land beneath your house. However, the crust is actually just a thin shell covering the earth. Sort of like the thin shell around this egg.

Obviously, the earth's crust is a lot thicker than the egg shell. Depending on where you are on the earth's surface, the crust can be anywhere from three miles to 43 miles deep. Wow. That's like eight times as tall as Mount Everest. Yeah. But even though that sounds like a lot, it's actually the thinnest layer. Whoa. The earth is bigger than I thought. It sure is. Now, go ahead. Take your egg. Crack the shell and peel it off. You see that white

layer underneath that's like the layer just under the earth's crust called the mantle. The mantle is our planet's thickest layer. It's more than 1,800 miles from top to bottom. Whoa. That's like flying all the way from New York City to Denver, Colorado. And the mantle is insanely hot. It can be anywhere from about 400 degrees Fahrenheit to more than 7,000 degrees Fahrenheit.

I'm sweating just thinking about it. Now, the mantle is going to be pretty important in our lava hunt, Volk. But before we get to that, I want you to break open that egg. Go ahead. Break it in half. What do you see? That's right. The yellow center.

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