The oceans are the largest entity on Earth’s surface. All that blue, however, may be dwarfed by an immense reservoir of hydrogen concealed in the planet’s heart. Experiments indicate that enough hydrogen to form dozens of oceans of water may have been entombed in Earth’s core during its formation, researchers report February 10 in Nature Communications. Those chthonic reserves may influence processes on the planet’s surface.
Hydrogen does not exist as liquid water in the core, but it becomes water as it escapes upward into the mantle and reacts with oxygen, says geodynamicist Motohiko Murakami of ETH Zurich. “Oxygen is one of the most abundant mineral elements in