Hydrogen at the core
Most of the Earth's hydrogen might be trapped in the core, says Takuo Okuchi at the Tokyo Institute of Technology, Japan. The finding may help explain the puzzle of low density of the Earth's core. Studies had shown that the core is nearly 10 per cent less dense than believed. During the formation of the Earth, most of the iron was dissolved in the central core. The iron-loving elements such as silicon, carbon and nickel were absorbed in the core. But these elements are also found abundantly in the crust and mantle. This mystery was partially solved by a study conducted by Okuchi. The geochemist heated and compressed iron and silica to create conditions as in the Earth's core and exposed them to water. The water's hydrogen was dissolved in the iron. The Earth's core might have been formed in the same way, says Okuchi. Geologists had ignored the possibility of hydrogen in the core as they thought that it was too volatile to be trapped in the core. Bernie Wood at University of Bristol, UK, says that during formation of the core, hydrogen may have prevented other elements from mixing in the core.