“It’s very exciting – and it could mean we have to rewrite the textbooks!”
Inner Core
At school, you probably learned that our planet consists of four different layers: the crust, the mantle, the outer core, and the inner core.
But new research by a team of scientists from the Australian National University (ANU) is shaking up the game: like a Russian doll, they say, the inner core has hidden another core in it.
This ‘inner inner core’ can be caused by a dramatic event early in Earth’s history.
“We have found evidence that may indicate a change in the structure of iron, possibly indicating two separate cooling events in Earth’s history,” said Joanne Stephenson, PhD researcher at ANU, and lead author of an article on the research conducted in the Journal of Geophysical Research: Solid Earth, said in a statement.
“The details of this great event are quite a mystery, but we have added another piece of the puzzle as far as our knowledge of the earth’s inner core is concerned,” she added.
Pointing crystals
The work builds on an older theory.
“The idea of another clear layer was proposed a few decades ago, but the data was very unclear,” Stephenson argued. “We got it right by using a very clever search algorithm to drag through thousands of the inner core models.”
Previous research indicates that this inner core appears to occupy half the diameter of the overall inner core and that iron crystals point in an east-west direction, as opposed to the outer, inner core, with the crystals pointing north. – to the south, enigmatic scientists.
The new research could have important implications.
“It’s very exciting – and it could mean we have to rewrite the textbooks!” Stephenson said.
READ MORE: Scientists dig deep to uncover Earth’s hidden layer [ANU]
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