In the 1980s, geophysicists discovered two continent-sized blobs of unusual material deep inside the Earth. These blobs, known as large low-velocity provinces (LLVPs), have intrigued scientists for years. A new study suggests that the LLVPs are remnants of an ancient planet that collided with Earth billions of years ago, creating our moon in the process. The study proposes that most of the colliding planet, dubbed Theia, was absorbed into Earth, forming the LLVPs, while residual debris coalesced to form the moon. This finding provides new evidence of the moon-forming giant impact, placing Earth into the context of the inner solar system formation.
https://news.asu.edu/20231101-asu-researchers-discover-earths-blobs-are-remnants-ancient-planetary-collision