Why Does Earth’s Inner Core Stay Solid Even Though It Is So Hot?

What Crafty Clover says in this video

Intro

Hi there, curious minds! I'm Crafty Clover! Let's discover something amazing. Why does Earth’s inner core stay solid even though it is so hot?

The Big Idea

At the very center of Earth sits a ball of iron and nickel as hot as the surface of the Sun. Even so, it is solid! Let's find out how a super-hot ball can stay solid.

Extremely Hot

Step one: extremely hot. Earth's inner core is a ball of iron and nickel about as hot as the surface of the Sun. You might expect something that hot to be melted.

Crushing Pressure

Step two: crushing pressure. The pressure at the center of the planet is millions of times greater than at the surface. That crushing squeeze keeps the metal atoms packed too tightly to flow.

Liquid Above It

Step three: liquid above it. The liquid layer above the inner core is under less pressure, so it stays melted. The inner core is a little smaller than the Moon, and it grows a tiny bit each year as the planet cools.

A Closer Look

Let's take a closer look! The inner core is solid. The outer core around it is liquid. Both are extremely hot. Pressure keeps the middle solid.

Quick Facts

Quick facts! The inner core is a little smaller than the Moon. It is about as hot as the surface of the Sun. Pressure is what keeps it solid. It grows a tiny bit each year as the planet cools.

Think Like a Scientist

Now, think like a scientist! Squeeze a handful of soft dough or clay hard in your fist. Notice how tightly it packs. Pressure packs the inner core in a similar way. Tell a grown-up what you feel.

Outro

Earth's inner core stays solid because the crushing pressure packs its atoms too tightly to flow. Science is amazing! Crafty Clover can be found on Amazon Books, Google Bookstore, and Apple Books. Available for purchase or download! Bye for now!