How big is the earths core

Around 760 miles (1,220 km)

At the center of the Earth is the core. According to NASA, It has two parts; The solid, Inner core which's made up of iron has around 760 miles (1,220 km). It's surrounded by a liquid, outer core composed of a nickel-iron alloy. The outer core is approximately 1,355 miles (2,1801 km) thick

Explanation:

answer; //i do believe its the caspian sea.