While the Earth's inner core has been widely believed to be made of solid metal, this may not be the case.
Earth's Inner Core
While it may seem that much is known about the Earth by this time, discoveries about the planet still surface now and then. Looking into the Earth's inner core is quite a difficult feat to pull off, as it is a terrain that humans are incapable of going to firsthand. Hence, studying the Earth's inner core could be as hard as studying exoplanets that are far away.
Now, yet another discovery has been added to what is currently known about the Earth's inner core.
Squishy, Not Solid Inner Core
The study "Collective motion in hcp-Fe at Earth's inner core conditions" claims that the supposedly solid inner core could be squishy. However, this squishiness does not refer to its composition. Rather, it refers to an atomic level. The study claims that the core's solid stuff lacks tangible things.
The Earth's inner core mainly consists of iron under great pressure and heat. On a molecular level, one may picture iron as some individual atoms kept together by orderly and neat patterns bonds. In most cases, the patterns appear like a series of cubes, with an added atom at the center. However, with the intense conditions at the Earth's core, the lattice self-rearranges to appear like a series of hexagons that take on a honeycomb-like appearance.
Though they could not directly sample the inner core, the researchers wanted a closer look at the lattice and the conditions that led to it. Hence, they subject an iron piece to significant and strong impacts to best replicate the conditions and their impacts. They then consolidated all the information on the effects on a computer and used artificial intelligence to extrapolate it to 30,000-atom supercells that could be studied.
As they looked into the supercell under the simulated conditions, the scientists discovered that the atoms at the honeycomb cells' corners were remarkably hyperactive and would swap places with each other frequently. Though this was insufficient to destabilize the solid iron or change its state completely, it appears to be enough to make the element squishy.
Youjun Zhang, one of the study's lead authors, explains that seismologists have discovered that the Earth's inner core is soft. Its softness could even be likened to butter in the kitchen. Zhang explains that the major discovery they came across is that solid iron turns shockingly soft deep inside the planet as its atoms move more than they imagined. This heightened movement leads to less rigidity in the inner core.
The idea of having squishy iron in the Earth's inner core is novel. While several theories about the inner nature exist, only time will determine which one will come out on top. At present, topic researchers are working on the confirmation of initial findings.
Check out more news and information on Geology in Science Times.
