What is the speed and timing of the Earth’s inner core cooling? This is what a recent study published in Nature Communications hopes to address as a team of scientists investigated the composition between the boundary of the Earth’s inner and outer core, as the inner core is solid iron while the outer core is molten. This study has the potential to help scientists better understand the internal processes of Earth, which could help shed light on other planetary bodies, as well.
For the study, the researchers focused on the crystallization that occurs between the outer and inner core, as the inner core cools and solidifies over billions of years. The goal of the study was to ascertain how the inner core crystallized over time and came to be in its present state. Using computer models, the researchers simulated the supercooling of the molten liquids existing within the outer core that eventually become part of the inner core. They focused on the elements of silicon, sulfur, oxygen, and carbon, and how they influenced the supercooling process. In the end, the researchers found that silicon and sulfur slowed down the supercooling process while carbon sped up the process.
“It is exciting to see how atomic scale processes control the fundamental structure and dynamics of our planet,” said Dr. Alfred Wilson, who is a research fellow at the University of Leeds and lead author of the study. “By studying how Earth’s inner core formed, we are not just learning about our planet’s past. We’re getting a rare glimpse into the chemistry of a region we can never hope to reach directly and learning about how it could change in the future.”
Diagram of the Earth's interior with the magnetic field interacting with the solar wind. (Credit: Dr. Alfred Wilson)
For context, the Earth’s inner core is estimated to begin at approximately 3,200 miles (5,150 kilometers), while the deepest humans have drilled into the Earth is approximately 7.6 miles (12.2 kilometers). Therefore, studies like this can help scientists better understand the Earth’s interior processes without the near impossibility of physically traveling to the Earth’s interior.
What new discoveries about Earth’s inner core will scientists make in the coming years and decades? Only time will tell, and this is why we science!
As always, keep doing science & keep looking up!
Sources: Nature Communications, EurekAlert!
