How can Earths inner core be solid iron if it is like the temperature of the sun?

Question

Today I read a story in the WP relating to the rotation of earths “solid” inner iron core. I looked it up from a different source that confirmed it is solid as opposed to liquid. How can it be so hot and not be molten? Thank you!

In: 81

Answer 1

The core temperature is probably around 4000-5000°C. This is around the temperature of the photosphere of the sun.

The reason it’s still solid is the extreme pressure. This high pressure locks the iron and nickel into a crystalline form despite the high energy of individual iron atoms. It prevents the iron atoms from moving around freely as in a liquid.