'9th Planet' Theia revealed just inside Earth

Scientists say the mysterious mass of material found deep in the Earth's core is the remains of an ancient planet that collided with Earth billions of years ago.

New simulations led by a research team from the California Institute of Technology (Caltech - USA) show that the ruins of the ancient planet Theia, in addition to the debris mixed with the Earth and Moon, also have two large pieces, intact, buried deep within the earth.

Picture 1 of '9th Planet' Theia revealed just inside Earth
Theia's collision with the early "Gaia" Earth - (Graphic photo: Hernán Cañellas).

Planet Theia - named after the goddess Theia in Greek mythology, mother of the Moon goddess Selene - is a hypothetical object the size of Mars, once an independent planet of the Solar System.

The theory is that it collided with the early Earth 4.5 billion years ago and was wiped out. The two planets' materials mixed together, with debris thrown into orbit condensing into the Moon.

Meanwhile, the "ultra-low velocity zones" are two mysterious continent-sized structures, located at the deep bottom of the Earth's mantle (the layer below the crust) below Africa and the Pacific Ocean, discovered in the 1980s through seismic data.

They are often called "blobs", with their distinct colors shown in stereoscopic maps depicting the planet's "interior" .

There are many theories surrounding these two "blobs" . There are two most prominent theories: They are the remains of ancient tectonic plates , or they are the remains of an ancient celestial body that once mixed with Earth.

"The impact appears to have been the origin of the early mantle's heterogeneity and marked the starting point for Earth's geological evolution over 4.5 billion years" - Professor Hongping Deng from the Observatory Shanghai Astronomical Survey, a member of the research team, said.

Professor Steven Desch of Arizona State University (USA) continued: "The moon appears to contain materials that represent both Earth and Theia before the collision, but it was once thought that any remnants of Theia had erased and homogenized by billions of years of dynamics".

So this new research published in the journal Nature demonstrates that separate, intact pieces of Theia still exist, hidden by Earth in the mantle, right on the boundary with the planet's core.

Picture 2 of '9th Planet' Theia revealed just inside Earth
The ancient planet Theia may have collided and mixed with Earth many billions of years ago. (MSN SCREENSHOT).

"In other words, Earth doesn't just have 'blobs'. Earth also has extraterrestrial blobs!" - Professor Ed Garneo from Arizona State University said.

Postdoctoral researcher Qian Yuan at the California Institute of Technology (CalTech), who led the above study, also has many theories about what happened to Theia and how it collided with Earth. Mr. Yuan and his team determined that the collision may have formed the moon and clumps of material in the Earth. Theia's crust can also merge into the earth's crust, solidifying and forming clumps of material.

Professor of geology and geochemistry Paul Asimov also at CalTech said that with the above hypothesis, it is necessary to learn more about how that formation affected the early evolution of the earth, such as the initial subduction phase. beginning before conditions became suitable for tectonic plates, the formation of continents and the origin of the oldest minerals.