Like a virtual journey to the center of the Earth, laboratory experiments are helping resolve a decades-old mystery that even Jules Verne couldn’t explain: what Earth’s core is made of.
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In particular, oxygen makes up a smaller percentage of the core than scientists had thought, suggests a study in the Nov. 24 Nature. Knowing the core’s contents helps researchers better understand how Earth clumped together 4.5 billion years ago, says coauthor Yingwei Fei, a geochemist at the Carnegie Institution for Science in Washington, D.C.
Arguments about the core’s chemical makeup have raged for nearly 60 years, says geophysicist Thomas Duffy of Princeton University. But “the work reported here suggests that a solution to the problem may finally be at hand,” he writes in a commentary accompanying the study.