Mondo Knows Facts
Earth inner core stays solid despite temperatures of five thousand degrees
Enormous gravitational pressure prevents molten iron from melting into liquid at the core
Earth's inner core is a solid sphere of iron-nickel alloy roughly 1,200 kilometres in radius located deep beneath the mantle. Although temperatures in the inner core reach about 5,400 degrees Celsius, matching the surface of the Sun, immense gravitational pressure of 3.3 million atmospheres squeezes iron atoms so tightly together that they cannot liquefy.
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Tags: earth science, geology, earth core
Earth inner core stays solid despite temperatures of five thousand degrees: the short answers
- Where does this come from, and can I check it?
- Enormous gravitational pressure prevents molten iron from melting into liquid at the core. The figure is taken from USGS, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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