A new study by researchers at The Australian National University (ANU) could help us understand how our planet was formed.
Associate Professor Hrvoje Tkalčić and PhD Scholar Than-Son Phạm, came up with a way to detect shear waves, or “J waves” in the inner core – a type of wave which can only travel through solid objects.
Associate Professor Tkalčić said:
“We found the inner core is indeed solid, but we also found that it’s softer than previously thought. It turns out – if our results are correct – the inner core shares some similar elastic properties with gold and platinum. The inner core is like a time capsule, if we understand it we’ll understand how the planet was formed, and how it evolves.”
Inner core shear waves are so tiny and feeble they can’t be observed directly. In fact, detecting them has been considered the “Holy Grail” of global seismology since scientists first predicted the inner core was solid in the 1930s and 40s.
Image credit NASA