[updated]As for this article, it was done a highlight with March issue of Nature Geoscience.

The paper "Low Core-Mantle Boundary Temperature inferred from the Solidus of Pyrolite" by ELSI director Kei Hirose and team appears in Science.

Hirose and team have discovered a large amount of hydrogen present in the Earth's core. This evidence shows that the Earth during the time of formation had a large amount of water (80 times that of ocean water) but that the majority of it has been incorporated into the core.

Sceince web page