In order to comprehend planetary origin and evolution, scientists have been investigating the Earth's centre for a very long time, and recently they have made a huge discovery related to the innercore of the planet Earth.
Until recently, it was believed that the crust, mantle, outer core, and inner core made up the structure of the Earth. But, new research published in Nature Communications confirms that there is actually a fifth layer.
According to a new study, scientists have made previously unheard-of observations of a mystery metal ball that resides within the Earth's deep core, revealing a structure that has long been the subject of conjecture but has never been seen in such detail.
Researchers said the intensive study of Earth's deep interior, based on the behavior of seismic waves from large earthquakes, confirmed the existence of a distinct structure inside our planet's inner core - a wickedly hot innermost solid ball of iron and nickel about 800 miles (1,350 km) wide.
Earth's diameter is about 7,900 miles (12,750 km). The planet's internal structure comprises four layers: a rocky crust on the outside, then a rocky mantle, an outer core made of magma and a solid inner core. This metallic inner core, about 1,500 miles (2,440) wide, was discovered in the 1930s, also based on seismic waves traveling through Earth.
"We may know more about the surface of other distant celestial bodies than the deep interior of our planet," said observational seismologist Thanh-Son Pham of the Australian National University in Canberra, lead author of the study published in the journal Nature Communications.
"We analyzed digital records of ground motion, known as seismograms, from large earthquakes in the last decade. Our study becomes possible thanks to the unprecedented expansion of the global seismic networks, particularly the dense networks in the contiguous US, the Alaskan peninsula, and over the European Alps," Pham added.
"Earth's inner core (IC), which accounts for less than 1% of the Earth's volume, is a time capsule of our planet's history. As the IC grows, the latent heat and light elements released by the solidification process drive the convection of the liquid outer core, which, in turn, maintains the geodynamo," said Pham and Tkalcic in the study.
"As the IC grows, the latent heat and light elements released by the solidification process drive the convection of the liquid outer core, which, in turn, maintains the geodynamo," they said referring to the mechanism that generates Earth's magnetic field.
(With inputs from Reuters)