Mysterious Missing Element Inside Earth’s Core Discovered? This Is What It Could Be

It is a well-known fact that about 85 percent of the Earth's innermost part is made of iron, while 10 percent is comprised of nickel. However, the remaining 5 percent that makes up the planet's core has remained a mystery. Now, a team of researchers from Japan has suggested that the mysterious element that comprises the missing 5 percent is actually silicon.

The Earth's core is located about 3,000 kilometers below the surface and is said to have a radius of about 1,200 kilometers. The depth of the core makes it impossible to directly carry out tests to find out what it is made up of. Incidentally, the deepest mines on the planet reach down to only mere depths of 4 kilometers.

According to a BBC report, the research team from Japan's University of Tohoku has been searching for the missing element for decades. The scientists carried out their study by creating a miniature Earth, complete with a core, mantle and crust in the laboratory instead of digging into the planet.

The team created alloys of nickel and iron and mixed them with silicon, and the resulting product was subjected to the high temperatures (about 6,000 degrees Celsius) and pressures that prevail within the Earth's core. The conditions were at par with the seismic data of the Earth's core and gave the researchers ample evidence that silicon was probably the missing element that constitutes 5 percent of the Earth's core.

"These difficult experiments are really exciting because they can provide a window into what Earth's interior was like soon after it first formed, 4.5 billion years ago, when the core first started to separate from the rocky parts of Earth," said Simon Redfern, professor of mineral physics at the University of Cambridge. However, Redfern also added that "other workers have recently suggested that oxygen might also be important in the core."