Mysterious blobs buried deep inside Earth's mantle, known as large low-velocity provinces (LLVPs), may hold the key to unraveling the origin of our moon, according to a new study. Scientists have long theorized that the moon formed around 4.5 billion years ago when a protoplanet called Theia collided with Earth. Computer simulations suggest that during the collision, a significant portion of Theia's material sank into Earth's mantle and over time, formed the blob-like structures we see today.
The LLVPs were originally discovered by seismologists, but their origin has remained a mystery. However, an international team of researchers, including scientists from the California Institute of Technology and the Shanghai Astronomical Observatory, used computer simulations to explore how the moon-forming event might have occurred. Their findings suggest that a portion of Theia's material could have sunk deeper into the Earth and eventually formed the blobs that are slightly denser than the surrounding mantle rock.
While the giant impact theory has gained significant traction, scientists have been on the lookout for concrete evidence to support it. The discovery of moon rocks could provide crucial insights into the composition of these buried blobs and help confirm whether they originated from Theia. In the coming years, as space agencies plan to establish a long-term presence on the moon, there is hope that these rocks will be brought back for further analysis.
Dr. Qian Yuan from the California Institute of Technology envisions future missions to the moon to retrieve mantle rocks that could have come from the impacting planet Theia. Comparing the chemical signatures of the lunar mantle rock to those of the blobs in Earth's mantle could provide strong evidence of a connection. However, more research is needed to fully understand the processes that led to the diverse makeup of Earth's deep mantle and how it relates to our moon.
The study has garnered praise from experts in the field, but they highlight the need for further analysis and discussion. Prof Alex Halliday from the University of Oxford commended the paper for its innovative thinking, but emphasized the need to address the challenges of reconciling the similarities between Earth and the moon while preserving the ancient heterogeneity of the deep mantle.
Understanding the moon's origin is crucial not only for unraveling the history of our solar system but also for future space exploration endeavors. By investigating the mysterious blobs deep underground, scientists hope to uncover more about the collision that formed the moon and shed light on the early evolution of Earth.