We all know our Earth has four layers: the crust, mantle, liquid outer core, and solid inner core. Now, researchers at Australian National University (ANU) have found evidence of a new, distinct layer within our planet’s inner core.
According to the researchers, this “innermost inner core” may have been formed following a “significant global event from the past.”
Researchers revealed this structure after intensively studying the Earth’s deep interior. Scientists studied the behavior of seismic waves from large earthquakes. The unprecedented observations help them confirm the existence of a distinct structure inside our planet’s inner core.
In this study, researchers revealed that this innermost inner core (IMIC) of Earth has a radius of about 400 miles. This is a solid metallic ball that consists of an iron-nickel alloy, like other parts of the core.
Although being made up of the same stuff as the rest of the inner core, this innermost core has different properties that determine how fast seismic waves travel through it.
Lead author, Thanh-Son Pham, said, “Clearly, the innermost inner core has something different from the outer layer,” “We think that the way the atoms are [packed] in these two regions are slightly different.”
Pham added, “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,”
Scientists foresee that this study help them in explaining the way our Earth became habitable to life. It could also help in providing new insights into the search for aliens.