Publication in Nature: The remains of the planetoid Theia have been found deep within the Earth’s mantle. This is therefore the same area where Helium 3 originates. Scientists have thus found the remains of the planetoid Theia, which collided with Earth 4.5 billion years ago, stripping away large portions of its mantle and thus giving rise to the formation of the Moon. This theory, of the Moon’s birth by the impact of a planetoid, was one of the main scientific findings of the Apollo missions: the Moon is made of Earth, specifically the Earth’s mantle. The remains of Theia are believed to be found, unevenly arranged, on the outer surface of our planet’s iron core, approximately 2,900 km below the surface. The presence of two massive “blobs” of laxative material, several thousand kilometers in horizontal dimension and several hundred kilometers thick, positioned deep beneath the mantle, has been known for several decades. One is located beneath Africa and one beneath the Pacific Ocean. These blobs are called “large low-velocity provinces” (LLVPs, for friends) due to the different speed at which seismic waves propagate through them, compared to their propagation speed in the mantle and Earth’s iron core. The research results are published in the scientific journal Nature. It should be noted, however, that this theory is only one possible one: another interpretation attributes the origin of the LLVPs to remnants of oceanic crust that ended up in the mantle through subduction billions of years ago.
