What Is the Outer Core?

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The outer core is part of the core, which is one of the three major layers of the Earth. The core is the deepest and hottest layer and is mostly composed of metals, and it is beneath the Earth’s mantle. The outer core is the first layer of the core, and it extends to a depth of approximately 2,890 kilometers below the Earth’s crust and measures 2,300 kilometers thick.

The outer core consists of hot lava that is comprised mostly of iron and nickel. This layer is so hot that all metals in it are in a liquid state. Iron and nickel are common metals found across the planet, and these metals exist in solid form on the Earth’s surface. In the outer core, they form an alloy. The outer core’s alloy is around 5,000 degrees Celsius. Below this layer is the inner core, which mostly consists of iron and measures 1,200 kilometers thick. The iron in this layer is much hotter, reaching 7,000 degrees Celsius, but the incredible pressure from the rest of the Earth keeps it from melting. For this reason, most of the inner core is solid. The planet’s core is rotating regularly, so the metals in it are constantly moving.