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Little is known the geology the very centre of Earth. It was believed our planet had just one core – a scorching hot mass molten rock and gas surrounded a solid, rock mantle. The mantle is a ring between the earth's crust and core. The core is found 2,900 kilometres Earth's surface. It has a radius of around 3,485 kilometres. Scientists the University of Chicago have discovered that there may be a second core deep below our feet. Research has led geophysicist Dr Sunyoung Park to believe there is another core. She analyzed data a 560-km-deep earthquake. Her calculations showed the possibility a second core, consisting a layer of fluid rock, the bottom of the mantle.

After Dr Park studied the deep earthquake, she spoke about why she found the Earth's core so intriguing. She said: "Even though the mantle makes the largest part Earth, there's still a lot we don't know it." She added: "There's a lot more we can learn using deep earthquakes as a way to probe these questions." Ms Park explained the importance understanding more about the centre our planet. She said: "We want to know exactly how fast the mantle flows because that influences the evolution the entire Earth. It affects how much heat the planet retains how long, and how the Earth's materials are cycled time. Our current understanding is very limited and includes a lot assumptions."

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