Scientists have long known that Earth's core is mostly made of iron, but the density is not high enough for it to be pure iron, meaning lighter elements exist in the core, as well. In particular, it's ...

Scientists used a new technique to estimate the abundance of hydrogen in Earth’s core. - Tumeggy/Science Photo Library RF/Getty Images Picture all of Earth’s oceans, which cover about 70% of the ...

Deep within Earth’s core, scientists are uncovering signs of a hidden structure that challenges long-standing models of the planet’s interior.

Picture all of Earth’s oceans, which cover about 70% of the planet and are mostly made of hydrogen. Now multiply that by nine. That may be the amount of hydrogen in Earth’s core, possibly making it ...