The outer core, about 2,200 kilometers (1,367 miles) thick, is mostly composed of liquid iron and nickel. The NiFe alloy of the outer core is very hot, between 4,500° and 5,500° Celsius (8,132° and 9,932° Fahrenheit)
Earth's outer core is a fluid layer about 2,400 km thick and composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle.
