Why Does The Earth Have Layers?

…or why do we live on an onion made of magma?

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Thanks to Miles Traer and Mike Osborne for geophysics help on this one!

Why does Earth have a liquid core, and how do we know?

How many pennies would you have to stack to melt the one on the bottom?

Why are the inner planets rocky and the outer ones are gas giants?

Produced for PBS Digital Studios

Joe Hanson – Host and writer
Joe Nicolosi – Director
Amanda Fox – Producer, Spotzen IncKate Eads – Associate Producer
Katie Graham – Director of Photography
Andrew Matthews – Editing/Motion Graphics
John Knudsen – Gaffer
Dalton Allen – Post-production Intern

Theme music:
“Ouroboros” by Kevin MacLeod

Stock images via Shutterstock

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