For years, two giant blobs of rock deep inside the Earth's core have puzzled researchers. Geologists investigating the formations have suggested they may be pieces of tectonic plates that got trapped under their counterparts.
However, new research is revealing that they may actually be of an alien origin.
Scientists from Arizona State University are now speculating the blobs may be remnants of a "Mars-sized planetary embryo" named Theia, which collided with Earth over 4.5 billion years ago.
This collision may even be what created the moon.
"The Moon is widely recognized as formed from the “Giant Impact”: when at least a Mars-sized planetary embryo Theia collided with the proto-Earth during the last stage of terrestrial planet formation. Such a model is well aligned with some key physical aspects of Earth-Moon system, including anomalous high angular momentum of Earth-Moon system, the small iron core of the Moon and its high mass ratio compared to the Earth," write the researchers in their study.
But how did they come to spot the two ginormous blobs called large low-shear-velocity provinces?
They did so by sending seismic waves down into the planet. They then discovered that under both Africa and the Pacific Ocean, the speed of these seismic waves slowed down significantly, indicating an area of rock denser than its surroundings.
The new research's simulations indicate that if the planet Theia was rich in iron and highly dense, any pieces of it that were released when it hit Earth would have sunk deep into our planet's mantle where they accumulated.
Researchers are still unsure exactly what these blobs are made of, but they have figured out that hot rock and magma from some Icelandic and Samoan volcanoes have come from them. If the study proves accurate, we may finally have proof that Theia existed and collided with our planet.