If you were to venture down through Earth's many layers to the very center of the planet, you'd find some interesting things. (Video via Google Earth)
You almost certainly wouldn't find Brendan Fraser, although if you did, it would explain a lot. (Video via Warner Bros. / "Journey to the Center of the Earth")
No, instead you'd find the Earth's inner core — a super-hot and super-compressed ball of iron smaller than the moon, which helps generate the Earth's magnetic field and, by extension, the aurora borealis. (Video via Science Channel, Visit Finland)
But scientists now think there's more to it than that — researchers think they've found an inner-inner core.
Iron at the Earth's core forms into crystals. The scientists found within the inner core, there's another region where the crystals don't line up with the rest of the inner core.
Specifically, while the inner core's crystals are lined up north to south, the inner-inner core's crystals line up east to west.
The discovery could shed light not only on how exactly the Earth's core works but also on how the core and the Earth itself developed billions of years ago. (Video via History Channel)
Obviously, scientists aren't able to actually drill to the center of the Earth to see the core and confirm their findings — that would entail some 4,000 miles of digging, withstanding millions of atmospheres of pressure, thousands of degrees Kelvin of heat and, of course, Brendan Fraser.
So instead, geologists tend to use seismological data — measuring how waves of energy generated by earthquakes and volcanic eruptions travel through the Earth's layers. (Video via Sternalia Productions)
The researchers measured the ways those different seismic waves were distorted as they travel to establish the orientation of the iron crystals. (Video via Wolfram Research)
An earth sciences professor at Cambridge told the BBC the researchers' model will now face further testing using other methods of seismic analysis.
This video includes an image from Waifer X / CC BY 2.0.