Silicon identified as 'missing element' in Earth's core

Silicon likely makes up a significant proportion of the Earth's core after iron and nickel, say scientists who claim to have identified the 'missing element' in the deep interiors of our planet that has eluded us for decades.
The discovery could help us to better understand how our world formed, researchers said.
For the study, researchers from Tohoku University in Japan recreated the high temperatures and pressures found in the deep interior of the Earth.
"We believe that silicon is a major element - about 5 per cent (of the Earth's inner core) by weight could be silicon dissolved into the iron-nickel alloys," said lead researcher Eiji Ohtani from Tohoku University.

The innermost part of Earth is thought to be a solid ball with a radius of about 1,200 kilometres.
It is far too deep to investigate directly, so scientists study how seismic waves pass through this region to tell them something of its make-up.

It is mainly composed of iron, which makes up about 85 per cent of its weight and nickel, which accounts for about 10 per cent of the core.
To study the unaccounted five per cent of the core, researchers created alloys of iron and nickel and mixed them with silicon, 'BBC News' reported.
They then subjected them to the immense pressures and temperatures that exist in the inner core. They discovered that this mixture matched what was seen in the Earth's interior with seismic data.