What if the Big Bang was a… big bite?!
This is Sandra Tsing Loh with the Loh Down on Science.
Hypothesis: Four billion years ago, a proto-planet, Theia, collided with Earth to form the moon. How do we know that?
Enter Qian Yuan and team from Arizona State University. They study large, low-velocity provinces, or LLVP’s. These are dense regions with low vibrations deep in Earth’s mantle. Using simulations, the team traced how Theia’s fragments could have sunk into Earth after the impact and become LLVP’s.
And? Like the moon, LLVP’s are rich in iron and make up three percent of Earth’s mass. These LLVP’s may in fact be remnants of Theia. Like swallowing cosmic chewing gum!
Looks like Theia left a core memory!
Reference: Yuan, Q., Li, M., Desch, S. J., Ko, B., Deng, H., Garnero, E. J., Gabriel, T. S. J., Kegerreis, J. A., Miyazaki, Y., Eke, V., & Asimow, P. D. (2023). Moon-forming impactor as a source of Earth’s basal mantle anomalies. Nature, 623(7985), 95–99. https://doi.org/10.1038/s41586-023-06589-1