Why Is Earth’s Inside So Hot?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why is Earth’s inside so hot?

The Big Idea

Earth's inside is hot for two reasons: leftover heat, and new heat that rocks keep making! It gets hotter the farther down you go. The center of Earth is about as hot as the surface of the Sun!

Leftover Heat

Step one: leftover heat. Earth grew from crashing, squishing rocks 4.5 billion years ago, and all that bumping made heat. Thick rock holds that heat for a very long time, like a cozy blanket.

Atom Heat

Step two: heat that keeps coming. Rocks hold tiny radioactive atoms. As they slowly break apart, they give off heat. Trillions of them keep Earth's inside warm, and they will for billions of years.

Squeezed Deep

Step three: a big squeeze. Deep down, rock presses on rock. Squeezing adds heat, and the pressure keeps most deep rock solid, even though it is super hot.

A Closer Look

Let's take a closer look! First, the crust, a thin skin of rock like an apple's. Next, the mantle, very hot rock that flows slowly. Then the outer core, which is melted metal, swirling around. In the middle, solid metal as hot as the Sun's surface.

Quick Facts

Quick facts! The crust is very thin compared with what lies beneath. Over millions of years, the solid mantle slowly flows. Volcanoes let some inside heat escape. Heat moves up from the center.

Think Like a Scientist

Now, think like a scientist! With a grown-up, pump a bike tire 20 times. Then feel the pump barrel near the bottom. It is warm, because squeezing air makes heat. Squeezing deep rock does something similar!

Outro

Earth's inside is hot from leftover heat and atom heat. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!