New research has shed light on the age of Earth’s inner core.
Turns out it’s younger than previous estimates, according to U.S. and Chinese scientists who collaborated on a study published in the journal Physical Review Letters earlier this month.
The new study estimates the Earth’s core is between 1 to 1.3 billion years old, which is lower than the previously estimated range of 1.3 to 4.5 billion years. But it’s also considerably higher than a recent estimate of only 565 million years.
The researchers came to this conclusion by recreating conditions similar to the centre of the Earth inside a laboratory chamber.
The Earth’s core is mostly made of iron, with the inner core being solid and the outer core being liquid.
Over a period of two years, the scientists tried to recreate the Earth’s core by squeezing laser-heated samples of iron between two diamond anvils.
“We encountered many problems and failed several times, which made us frustrated, and we almost gave up,” said the study’s co-author Youjun Zhang, an associate professor at Sichuan University in China.
The experiments also give the researchers more insight into how the core conducts heat and the energy sources that power the Earth’s geodynamo.
The Earth’s geodynamo is the mechanism that sustains the Earth’s magnetic field, which keeps compasses pointing North and helps protect life from harmful cosmic rays.
“People are really curious and excited about knowing about the origin of the geodynamo, the strength of the magnetic field, because they all contribute to a planet’s habitability,” said lead researcher Jung-Fu Lin, a professor at The University of Texas at Austin’s Jackson School of Geosciences.